Abstract of Papers to be Presented at the Southern Divisional Meeting of the American Dairy Science...

A S S O C I A T I O N AFFAIRS

ABSTRACTS OF PAPERS TO BE PRESENTED A T T H E

S O U T H E R N D I V I S I O N A L M E E T I N G

of the

A M E R I C A N D A I R Y SCIENCE A S S O C I A T I O N

New Orleans, Louisiana February 2 - - 5, 1975

Elucidation of product formation and postu- lated mechanisms for phytate metabolism in the ruminant. A. B. Bodine* and G. D. O'Dell, Clemsort University, Clemson, S.C.

Ruminant utilization of phytate has been documented. Mechanism(s), intermediates, and enzyme(s) involved have not been determined adequately. Rumen phytase reactions were investigated by chromatography, eleetro- phoresis, crystallization, distillation, and melting point techniques. (1) Products formed from rumen phytate digestion differ in type and/or stereochemistry from those of wheat bran phytase; i.e., little, ff any, di- or mono- phosphate was formed from phytate digestion in vitro. (2) Larger quantities of "abnormal" triphosphate isomers were produced from rumen fluid phytate digestion than from wheat bran phytase. (3) Certain mono and divalent ions increased phytate solubility and digestion rates. (4) Magnesiun+ + and urea did not alter significantly the amount of phosphate produced from phytate. (5) Although there was a reduction in total phosphatase activity, there was a greater reduction in phytase activity between intact and lypholized rumen fluids. (6) Rumen fluid digestion of inositol yields aldehyde 2,4 dinitroohenylhvdrazone deriva- tives different from those of phytate (thus pre- cluding dephosphorylation of phytate to inosi- tel).

Three protein percents in complete rations and their supplementation with molasses or liquid supplement for lactating cows. Jose R. Flores*; S. P. Marshall, and H. H. Van Horn, University of Florida, Gainesville.

Protein 11.5, 13.0, or 14.5% (air dry basis), was fed to 18 Holstein cows for 8 wk after which a second percent was fed for 8 wk. Ad- ditionally, three cows received each of the three protein percents continuously over the

*Author presenting paper.

16 wk experiment. Rations contained 25.0% sugarcane bagasse pellets and 37.0% citrus pulp plus corn and soybean meal in amounts to give desired protein. Three treatments (control, molasses, or a molasses-ttrea liquid supplement fed by lick-wheel up to 1.82 kg per cow daqy) were factorialized into the design and switched every 4 wk. This partially balanced, incomplete block design with four 4-wk periods was analyzed by least squares. No main differences were significant except responses of milkyield to protein percent. There was an interaction of protein and liquid sttpplements in which blood glucose was increased by liquid supplements in higher protein diets but not in low protein diets.

Utilization of micronized sorghum grain by dairy calves. Abdulla Ahmed*, L. J. Bush, and G. D. Adams, Oklahoma State University, Still- water.

Twenty-four Holstein and 18 Ayrshire calves were used to compare the utilization of dry rolled and micronized sorghum grain. Calves within each breed were randomized into three groups, (1) control (dry rolled), (2) micronized (230g/liter) and (3) microuized (380g/liter). During 8-wk, weights were recorded weekly. Rumen samples for volatile fatty acid determination were taken 3 to 4 h after feeding during the 4th wk. Mean weight gains of calves on each treatment by breed were: Ayrshire, 42.4, 42.7, and 38.2 kg for groups 1, 2, and 3; Holstein, 49.7, 44.2, and 52.3 kg. No differences in proportions of volatile fatty acids due to rations were significant. Nine bull calves were in a 3 X 3 Latin square design for digestion studies. No differences among rations were significant in digestibility of dry matter, starch, crude protein, or organic matter.

Incidence of mastltis-producing pathogens in Georgia..1. F. Holmes* and C. H. Vfhite, Uni- versity of Georgia, Athens.

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Five dairy herds in northeast Georgia were screened for mastitis with emphasis on the eti- ological ager~t. Herds were Holsteins and Jer- seys. Each herd was sampled three times over 6 me. Quarter samples were taken aseptically from each cow as was a composite from bulk sample tank. Milking practices were noted and compared with laboratory screening tests.

Lal~ratory screening tests included: (I) California Mastitis Test, (2) Wisconsin Masti- tis Test, (3) Direct Microscopic Somatic Cell Count. Samples were streaked on (1) Blood Agar (2) Tellurite Glycine Agar (3) Eosin Methylene Blue Agar, and (4) Mannitol Salt Agar. Standard Plate Counts were run on 10% of the cows of each herd and on every bulk tank sample. Over 50% of quarters had patho- genic bacteria. Most common in infected quarters was Sta79hglococcus aureus. Strain resist- ance to antibiotic-disc sensitivity testing was variable with tetracycline, erythromycin, and cloromycetin being the most effective in ther- apy.

Regression analyses of bovine blood serum charaeterlsties with environmental temperatures and milk yield. Linda M. Shaffer,* J. D. Roussel, and Louis Comila, Louisiana State University, Baton Rouge.

Nine lactating Holstein cows were subjected to eight periods of constant temperature at 15.5, 18.5, 21.2, 24.0, 26.8, 29.5, 29.5, and 29.5 C with each period 7 days. A constant relative humidity of 65% and artificial light (12 h) were maintained throughout this investigation. Ten blood serum characteristics were assayed by Hveel Mark X analyzer. Regression procedures were used to develop a prediction equation for milk yield from the characteristics. The full model of cow temperature, crea- tine phosphokinase, glutamic oxaloaeetic trans- aminase, phosphorus, alkaline, phosphatase, calcium, cholesterol, total protein, globulin, urea nitrogen, and glucose accounted for .93 of the variation in milk yield. A modified model of cow temperature and cholesterol ex- plained .91 of the variation in milk yield.

Effect of dry scrape, domestic water rinse, and recycled w a t e r rinse on mieroflora of a dairy cattle holding lot surface. Donald L. Herman* and E. W. Custer, Mississippi State University, Mississtl~pi State.

We studied holding lot surface to determine the effect of dry scrape, domestic water rinse, and recycled water rinse from a three stage JOURNAL OF DAIRy SCIENCE VOL. 58, NO. 1

dairy animal waste treatment lagoon system upon mieroflora o.f dae holding lot surface for dairy cattle. Swab samples were obtained from the lot surface just after trea~nent and 4 h post-treatment. Microbiological test consisted of total count, total coliform, fecal coliform, fecal Streptococci, Staphylococcus, Salmonella, Shigella, and isolations were made for additional enteric ty-l~s. The results inch'cated no survival of Staphylococcus, Salmonella, and Shigella organisms upon the dairy cattle holding lot surface 4 h post-treatment. Coliform or-

anisms significantly decreased during lot ex- L u r e but increased more fro~ domestic rinse treatment than the other treatment types. Four hundred bacterial isolations were made during the test period in which Cornybaeterium, Pseu- domonas, Proeteus, E. cell, and minor Entero- bacter organisms represented majority groups.

Housing systems for dairy calves from birth to three months. R. E. Freeman*, R. B. Moore, W. H. Brown, and K. R. Cummings, MAFES, Mississipoi State University.

Sixty-three Holstein calves (29 male and 34 female) were used to compare three housing svstem.s. Two sections of an enclosed cold barn differing in insulation and ventilation were des- ignated as units A and B with outside portable pens being the third system. The inside units contained elevated individual pens with three types of floors (oak, cypress slats, or expanded metal). All calves were fed milk replacer once a day to weaning at 30 days and a calf starter. Mean values of animal performance from 0 to 3 me of age were: Average daily gain (kg) --.58, .56, and .54; feed efficiency (kg) - 3 2 3 , 3.23, and 3.11; medical cost ($) --3.81, 5.18, and 5.34; and a fecal condition (4 --- solid, 1 = liquid) --3.49, 3.36, and 3.41 for calves in A, B, and outside units. En- viromnental conditions were monitored, continuously and mean air temperature and relative humldi~ for units A. B, and outside were 13.5 C, 72.8%; 14.8 C, 70.9%; and 11.5 C, 70.0%. All w e r e within recommended ranges.

Milk coagulation test for diagnosis of early pregnancy in dairy cows. J. P. Abilay* and J. D. RousseI, Louisiana State University, Baton Rouge.

Two trials of 171 cows were to determine the reliability o,f milk coagulation test as a method of diagnosing early pregnancy in cows and to ascertain the stage of pregnancy at which the test is highly applicable. Milk samp- pies were collected and brought to the laboratory for pregnancy test by 3% pure copper sul-

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fate solution. Ten milliliters of 3% copper sul- fate solution were placed in 20 ml test tubes, and 1 milliliter of milk sample was added and stirred. Coagulation of the milk samples was positive for pregnancy while those that remained homogenous were considered negative for pregnancy. The accuracy of results of the tests were confirmed by comparing them with the result from pregnancy test by rectal palpation 60 days after insemination. Results indicate 50, 85, 67, 58 and 40% accuracy in de- tecting pregnancy at 1 to 29, 30 to 45, 46 to 60, 61 to 90, and 91 or more days of pregnancy. The findings tend to show a decreasing percentage accuracy of the test as pregnancy ad- vances.

Steroid based early pregnancy diagnosis. J. C. Bergeron*, J. D. Ronssel, D. G. Satterlee, and E. T. Segnra, Louisiana State University, Baton Rouge.

Blood samples from 44 bovine females of breeding age were obtained to determine the validity of early pregnancy testing via plasma progesterone assay. Effects of day of bleeding (day 19 post insemination versus day 20), source of collection (jugular versus coccygeal), and treatment of blood (normal versus trauma- tized) were examined. Total corticoids were also determined on 16 animals for correlation with progesterone data. Progesterone changed with source and treatment. Corticoids changed with source and day by source interaction. Based on a progesterone index of 2.0 ng/ml, a 67% accuracy of diagnosis was confirmed by rectal palpation.

Determination of protein content of milk by mierodiffusion. R. H. Lin* and H. E. Ran- dolph, Texas A & M University, College Sta- tion.

A mierodiffusion procedure for determining protein content of milk was investigated. Pre- liminary studies revealed that a modified Con- way mierodiffusion procedure did not differ significantly from miero-Kieldahl distillation in the recovery of ammonia from ammonium sul- fate solutions (.01 M to .0005 M). Total and whey protein concentrations of milk from Hol- stein and Jersey cows were determined by mi- crodistillation and microdiffusion of miero- Kieldahl digested samples. Results by micro- distillation and microdiffnsion for protein content of 38 samples of milk (3.42 and 3.38%; r = .99) and 40 samples of whey (.88 and .87%; r = .99) did not differ significantly. Mi- erediffusion procedure offers improved efficien-

cy while maintaining accuracy of the micro- Kjeldahl.

In vitro digestibility of segmented and whole plant sorghum silage from two varieties. R. E. Spiegel*, G. T. Lane, R. E. Lichtenwalner, and Rebecca J. Ahrer~s, Texas A & M Univer- sity, College Station.

Sorghum grain varieties, OROT and FSlb, were sampled weekly beginning at bloom stage and sectioned into head, leaves, and stalks or left as whole plant. Protein, dry matter, and in vitro digestible dry matter were studied. Protein decreased from 13.3 to 11.0 and 11.2 to 6.9% for OROT and FSlb. Leaves were highest in protein at bloom while heads were highest at harvest. Digestible dry matter for OROT and FSlb at bloom was 74.9 and 76.6, 59.3 and 67.4, 78.2 and 81.1, and 73.3 and 67.5, and at harvest 80.3 and 74.5, 85.1 and 80.9, 70.4 and 72.2, and 63.6 and 71.9 for whole plant, head, leaves, and stalk. Percent of total contributed by the various plant sections for OROT was 16.3, 46.0, and 42.7 at bloom and 54.5, 23.1, and 22.4 at harvest and for FSlb 23.9, 27.5, and 53.6 at bloom and 31.1, 17.6, and 51.3 at harvest for heads, leaves, and stalk. In vitro acetic acid was highest in leaves and 1.ovvest in stalk. Propionic acid was highest in stalk, and lowest in leaves.

Influence of exogenous enrticetrophie and cli- matological interactions on adrenal cortical function. Daniel Satterlee*, J. D. Roussel, and Eugene Segura, Louisiana State University, Baton Rouge.

Six pregnant Holstein heifers were utilized to test interactions between different climato- logical conditions and exogenous adrenocorticotropin on adrenal cortical function. Animals contributed data under cold (5 C, 30% relative humidity), neutral (18 C, 50%), and hot (35 C, 60%) environments. After an l 1-day acclimation under each environmental regime, three heifers received 200 IU of adrenocorticotropin and three received a .9% saline solution intraveneously, followed by the reverse- merit of treatments 7 days later. Cannula collection of blood samples at 30 rain pre-iniection and 5, 30, 60, 90, 120, 180, and 240 rain post- injection as well as, at 12, 24, and 48 h post-injection revealed increases in plasma progesterone and total eorticoid with magnitudes and durations of these post-injection responses being similar across all environments. Total corti- colds were influenced by interval and treatment by interval effects. Interval affected progesterone.

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Effect of exogenous adrenocorticotropin under three environments on thyroid activity in dairy heifers. Eugene Segura,* J. D. Roussel, and Daniel Satterlee, Louisiana State University, Baton Rouge.

Six Holstein heifers 90 to 120 days pregnant were subjected to three environments; (1) Cold (5 C, 30% relative humidity), (2) Neu- tral (18 C, 50%), and Hot (35 C, 60%). Three heifers received 200 IU of adrenocorticotropin and three received a .9% saline solution intravenously under each environment, with treatments reversed 7 days later. An 11- day acclimation to each environment was allowed. Blood samples were collected via in- dwelling jugular catheters at - 3 0 min pre-in- jeetion and 5, 30, 60, 90, 120, 180, and 240 min post-injection and at 12, 24, and 48 h pest-injection. Protein Bound Iodine determined by the Hycel Cuvette PBI method was affected by treatment X environment interaction, interval, and treatment X environment X interval interaction.

Roof sprinkling and insulation in a freestall barn for lactating cows during the summer. A. B. Zook*, J. W. Fuquay, and W. H. Brown, Mississippi State University, Mississippi State.

One section of a freestall barn modified with roof sprinkling and overhead insulation was up to 3.3 C cooler during mid-afternoon than an unmodified control section. This modi- fication was tested in a switch back design utilizing 10 lactating cows per treatment with 1 wk adjustment and 2 wk treatment periods. AnLrnals were group fed corn silage ad libitum the first period and sorghum sudan greenchop for the remainder of the experiment. A 16% protein concentrate containing .5% urea was fed individually at 1:9..5. Cows in the modified section had a lower respiration rate (70.9 versus 78.2) than cews in the unmodified section of the barn. Body temperature tended to be lower for those in the modified section. For treatment and control groups, means for body temperature, milk production, milk fat percent, and protein percent were 38.7 C, 17.9 kg, 3.81, 3.28, and 38.8 C, 17.9 kg, 3.86, 3.30.

Selected dairy and poultry lagoons in north Louisiana. D. G. Kelly*, R. H. Cough, J. H. Gholson, A. V. Davis, A. C. Goodling, and R. S. Woodward, Louisiana Agricultural Ex- periment Station, Baton Rouge and Calhoun.

Lagoon waste disposal systems in a dairy and poultry operation located on a branch experiment station were studied for 1 yr. The JOURNAL OF DAIRY SCIENCE VOL. 58, NO. 1

dairy operation consisted of a two lagoon system with overflow on a grass waterway while the two lagoon poultry operation was self-contained, and water from the aerobic lagoon was used to wash and fill under bird cages. The solid wastes going into the dairy and poultry lagoon systems were analyzed monthly for chemical oxygen demand, dry matter, ash, and volatile solids. Ranges of values were chemical oxygen demand (ppm) 147,300 to 223,- 100, and 24,500 to 53,600, dry matter (%) 13.0 to 14.9 and 2.7 to 5.6, ash of dry matter (%) 12.2 to 16.9 and 20.2 to 30.8, volatile solids of dry matter (%) 83.1 to 87.8 and 69.2 to 79.6 for dairy and poultry wastes. Ranges of the monthly biological oxygen demand values (ppm) were: anaerobic lagoon 34 to 87 and 95 to 353, aerobic lagoon 4 to 99 and 26 to 119 for dairy and poultry waste. Total rainfall for the year was 1.73m. Ambient and lagoon temperatures were taken also.

Problems associated with determining fat content of ultra high temperature products. Wil- liam Gillis* and E. W. Custer, Mississippi State University, Mississippi State.

With the current shift toward ultra high temperature processing of products with high fat content, there have been discrepancies in fat testing procedures for these products. We attempted to determine different results for the Mojonnier, Baneo, and Babcock methods. Sterile ultra high temperature products were obtained from one company, and conventional- ly processed products were obtained from another company. Products were whipping cream, half and half, and chocolate milk. Con- ventional products were controls. Samples from each company were collected once a week and all analyses were on the same day to omit day to day testing variation. Each test was in duplicate. Readings of Mojolmier and a modified Babcock method agreed. The Banco test failed to be consistent in producing re- suits comparable to the other two methods.

Fat test depression during storage of test milk samples in plastic containers. C. W. Dill, S. A. Herlick, and J. W. Davis, Texas A & M University, College Station.

Depressions in fat tests were ambiguous when milk samples were stored prior to testing by the Milko-Tester procedure. Fat test depression was augmented by shipping and by chilling samples at time of collection in an ice- water mixture. The effect was greatest in samples stored in plastic containers. The effect was not significant in samples stored in glass bet-


tles or in plastic coaltainers with no refrigera- tion during storage.

Effects of oxidase-positive psyehrophiles on the keeping quality of milk. J. J. Janzen, A. B. Bodine*, and F. M. Crawford, Clemson Uni- versity, Clemson, SC.

Numerous workers have reported that psy- chrophilie bacteria are the major contributors to eduction of shelf-life in commercial milks. However, a comprehensive evaluation of in- terrelationships of flavor scores and oxidase- positive bacteria counts has been neglected. Predictive equations relating initial oxidase- positive counts to the ultimate 10- or 14-day flavor score could be valuable in the milk industry. Research incorporated bacterial counts, rates of pro teolysis, by-product distribution, and flavor scores. Oxidase-positive counts were correlated with flavor, lactose utilizatioaa, and rate o~ gelatin liquefaction (proteolysis).

Major components in fractions of fresh and au- toxldized milk. Arvind Patel*, Morrison Loew- enstein, C. H. White, and C. M. Clifton, Uni- versity of Georgia, Athens.

Many studies have been made of the fat globule membrane; the nature of washed cream, fat globule surface structure, and washed cream "buttermilk" have been de- scribed. The litera~re contains few data as to the composition of materials eroded from fat globule surfaces by successive washings. This report provides data on the composition of three waslx fractions and other fractions of milks studied for autoxidation. Data have been collected to show the maior components of interest in fresh whole milk, and the same milks after storage 72 h at 5 C, some of which be- came oxidized. Those compo,nents included total solids, protein, lactose, ash, total lipid, yhospholipid, and tocopherol. The distribution of a number of minerals between the fractions was also determined. Similar data are presented for 10 fractions of such milk, includ- ing those materials recovered in the washing of the cream and the washed cream.

Brom thymol blue as indicator for rancidity measurements in milk. ]. J. Janzen*, A. B. Bodine, and F. M. Crawford, Clemson Uni- versity, Clemson, SC.

The development of rancid flavor in milk and some o~ its products is usually undesirable and detracts from their market value. A sim- plified titration procedure for estimating the

extent of hydrolytic rancidity in milk has been widely used by industry to help control this defect. The one possible disadvantage of this test always has been the accurate detection of the phenolphthalein end-l~-nt. Because of this difficallty, the use of an alternative indicator, brom thymol blue, has been investigated. The results of comparative analyses show no significant differences in precision for these two indi- cators. Some of the possible advantages for the use of brom thymol blue will be discussed.

Relation of chemical and physical properties to rancid flavor scores and acid degree values of raw milk. Y. A. Asher and J. T. Cardwell*, Mississippi State University, Mississippi State.

Data from 54 individual cow saml~]es of raw milk were analyzed by linear least-squares curve fitting program. Two dependent variables, acid degree values and flavor scores were correlated separately with eight independent variables. The independent variables were: fat percent, protein percent, pH, initial lipase activity, mean diameter of fat globules, stage of lactation, and percent proportions of two casein fractions. Partial regression coefficient (bi) for initial lipase activity was significant and positive in both eases; bl of pH was significant and positive for flavor scores, bi of stage of lactation was significant and negative for acid degree values. Fat globule diameter and percent proportions of casein fractions showed high bi values. The b~'s of protein percent and fat percent were low. Multiple correlation coefficients (R) were .62 for flavor scores and .59 for acid degree values.

Lipolytic aetivlty in the mierosomal fraction of bovine skim milk. C. W. Dill*, Edna Sustek, and S. A. Herliek, Texas A & M Urfiversity, College Station.

Lipolytie activity is demonstrated in the plasma membrane fraction eluted in the void volume from a Sepharose 4B column. The eluted fraction demonstrated a specific activity time in skim milk and was only one of several molecular weight species possessing ]ipo- lytie activity after elufion from Sepharose 413.

Effect of freezing cheddar cheese on the survival of certain microorganisms. Joe T. Card- well* and C. W. Shannor~, Mississippi State University, Mississippi State.

The effect of freezing cheddar cheese or~ survival of microorganisms of cheddar cheese was evaluated. Sub-samples of cheese were ~

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stored for 30 and 90 days at --29, --18, 7, and 21 C, then analyzed for bacteria population. Standard methods were used to estimate numbers and types of bacteria. The counts were lower after 90 days storage than after 30 days storage. Cheese subjected to freezing at - -29 C resulted in the largest survival of coliform organisms and the lowest psychromphflic and tot.al bacteria (standard plate count). The cheese solids seemed to protect the coliform bacteria subjected to freezing and thawing. Cheese stored at 21 C had the lowest coliform counts and the highest total counts, indicating a competitive effect of desirable organisms over undesirables. There was no positive reactions for pathogenicity. Portions of the frozen cheese samples were thawed and allowed to age for 9 me at 7 C. One could assume that adequate bacteria survived the freezing treatments since these thawed samples developed normal flavor, body, and texture characteristics.

Quality of ice cream sold in retail outlets. C. H. White*, J. F. Holmes, S. J. Speck, M. Loewenstein, and M. K. Galal, University of Georgia, Athens.

Vanilla ice cream sold in 1.9 liter containers in retail outlets in Georgia was analyzed over 9 me. Most Georgia met minimum standards. Out of 210 samples, only 7% did not meet the net weight minimum of 1022 g. Only 1% ex- ceeded the 50,000/g maximum limit for total bacteria. Sixty three percent had zero coil- forms. Milkfat. varied most with a low of 4.42% and a high of 17.0%. There were 40% samples below 10% fat. Total solids ranged from a low of 25.14% to a high of 44.10%, Melt down properties for most ice cream were good with only 17% of the samoles melting in excess of 30% of the preweighed volume. A syrup flavor occurred 30.5% of the time. Cooked flavor and samples lacking a vanilla flavor were the next most frequent flavor cr/ticisms, both 26% of the time. Body ar~ texture score averaged ap- proxirnatelv .5 unit higher than the sample after it was heat shocked. There appeared to be a slight, but significant correlation between price, as paid at the retail outlet, and flavor s c o r e .

Effect of intrauterine infusion with Furacin on reproductive efficiency in dairy cattle. J. W. Daniel*, J. F. Bcatt?¢, J. W. Fuquay, W. H. McGee, D. E. Pogne, F. D, Shumaker, and G. L. Tune, Mississippi A~ricultural and For- estry Experiment Station, Holly Springs, New- JOURNAL OF DAIRY SCIENCS VOL. 58. NO. I

ton, and Mississippi State. One hundred-fifty-five dairy cattle from

three experiment station herds were, within lo- cation, alternately either treated by irffusing 40 ee of Furacin into the uterus on the estrus before planned insemination or maintained as a control. All reproductive tracts were examined by rectal palpation at the estrus before insemination to determine the degree of in- volution. Animals were inseminated at each observed estrus after treatment until conception occurred. A detectable amnion or fetus 40 to 60 days postserviee was the criteria for conception. Days to first service, days to con- coption, and services per conception for the treated and control animats, respectively, were 73.7, 104.9, 2.05 and 74.4, 106.1, 1.92 with no significant treatment differences. Uterine ffffections were observed in 6 treated and 12 control animals during the early postpartum period but were not apparer~t at the time of treatment. It was concluded that routine treatment of all cows with Furacin should not be recommended.

Effects of 45 days versus 60 days postpartum breeding on calving interval and fertility. Louis Gomila* and J. D. Roussel, Louisiana State University, Baton Rouge.

One hundred and fifty lactating dairy cows were randomly assigned to one of four grottps. Group I consisted of animals whose first service occurred between 46 and 65 days post- partuln. Groups II and III were composed of animals with their first service occurring, respectively, in the 66 to 85 or 86 to 105 days postpartum. Group IV consisted of animals that exhibited es,~us between 46 to 65 days but were not bred. Animals were examined between 40 to 45 days for reproductive fitness. Eighty animals (Group I) were randomly assigned to be bred during this period ff they cycled. The mean rmmbers of days open were 98.0, 98.5, 127.9, 144.2, and 126.5. Eliminat- ing the animals considered to be problem breeders (four or more services) gave mean open days: 76.0, 108.1, 127.9, and 113.7. The mean services per conception were 2.14, 2.65, 2.34, and 1.93. When the problem breeders were eliminated, average services of 1.51, 1.82, 1.75, and 1.58 were required. These re- suits suggest that breeding at 45 days postpartum would be advantageous.

Fine structure of the ampulla of bovine ovi- duct. L. T. Blartkenship*, J. F. Dickey, E. R. Holliday, and A. R. Ellicott, Clemson Univer- sity, Clemson, SC.


Ampullae from oviducts of 23 Hereford and Angus heifers were obtained within 30 min after slaughter. Tissue was taken 2 cm from the inftmdibulum, processed, and embedded for electron microscopy. Two distinct types of cells (ciliated and nonciliated) were present. The cytoplasm of ciliated cells was more electron dense but had less organized granular ende- plasmie retieulurn, more mitochendria, and more basMly situated nuclei than nonciliated cells. Numerous microvilli were interspersed among the cilia at the apical surface of the cells; basal bodies and rootlets extended into the cellular cytoplasm. Nonciliated cells had great amounts of granular endoplasmic reticulum, cytoplasm protruding well into lumenal space, and nuclei situated at various levels in the cells even in the cytoplasmic protrusions. Cells which contained nuclei in the cytoplasmic protrusions did not extend to the basal lamina, suggesting that these cells were being extruded into the lumen; however, these pro- trnsions had normal appearing nuclei, well developed granular endoplasmic reticulum, a few mitochondria, and some secretory granules. Nuclei of both types of cells had relatively condensed chromatin and frequently had cytoplasmic invaginatiens which contained tubular shaped granular endoplasmie reticulmn.

Fine structure of the isthmus of bovine ovi- duct. J. F. Dickey*, E. R. Holliday, L. T. Blankeuship, and A. R. EUicott, Clemson Uni- versity, Clemsen, SC.

Isthmuses were obtained from the oviducts of 23 Hereford and Angus heifers within 30 rain after slaughter. The ,tissue was taken from an area about 2 can from the uterotubal junc- tion, processed and embedded for electron microscopy. Columnar epithelium of the isthmus consisted of two types of cells, ciliated and nonciliated. Except for the cilia which extended into the lumenal space, heights of the two cell types were similar. In eiliated cells, cytoplasm was less electron dense, contained more mitochondria, and nuclei were more rounded with less condensed chromatin material than in nonciliated cells. Numerous microvilli were interspersed among the cilia at the apical surface of the cells. Nuclei, especially in the ciliated cells, were located in the basal portion of the cells. Cytoplasmic invaginatiens in the nuclei were frequent. Some granular endoplasmic reticulum, numerous free ri- bosomes, and many electren epaque bodies were in nonciliated cells. Relatively large inter- celhdar spaces, especially in the basal portion of the epithelium were observed. Desmesomes

were located at intervals along the celhdar membranes between cells.

Effect of methionine hydroxy analog on postpartum interval and reproductive efficiency in dairy cattle. J. W. Fuquay*, W. H. McGee, and E. W. Custer, Mississippi State University, Mississippi State.

This investigation was to determine if sup- plementing the diet with methionine hydroxy analog would shorten ,postpartum interval, thus providing potential for higher reproductive efficiency. Forty-five dairy cattle supplemented with 25 g methionine hydroxy analog per day dm'ing the early part of the lactation (35 cows for 120 days; 10 cows for 60 days) were compared with 38 controls on the same nutri- tional program except for the supplement. A concentrate with 16% crude protein was fed at 1:2.25, and coru silage or fresh green forage was fed ad libi~m. All animals were checked for estrus twice daily and were inseminated at each estrus after 60 days postpartum until conception occurred. Pregn.an~y was determined by rectal palpation 40 to 60 days postservice. Means for days to first estrus, days to first service, days to conceptien, and services per conception for the supplemented and eor~trol animals were 38.6, 73.7, 115.1, 2.73; and 45.8, 77.3, 135.4, 3.03.

Serum lipid response of dairy cattle in mid- lactation to methionine hydroxy analog during conditions of summer stress. J. W. Fuquay*, W. H. McGee, and P. T. Chandler, Mississippi State University, Mississippi State, and Vir- ginia Polytechnic Institute and State Univer- sity, Blaeksburg.

Within pairs by breed and milk productiorg 18 lactating dairy cows were supplemented randomly with either 24 g methionine hydroxy analog per day or maintained as a control during an 80 day continuous study. Sorghum- sudan greenchop (ad libitum) and a concentrate of 16% crude protein (1:2.5) were fed all animals. Blood samples were drawn on days 63 and 77, and serum lipid classes were determined by thin layer chromatography. Maxi- mum and minimum tempera~res for sampling days I and II were 29 to 16 and 34 to 24 C. No lipid dames were altea-ed by the supplementation. Lysoleeithin (15.1 versus 7.7 rag per 100 ml serum) and lecithin (94.6 versus 123.9 mg per 100 ml) differed between sampling periods. No treatment by sampling period interactions were detected. Means for the polar and neutral lipids for the treatment and control groups

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were 178.0, 203,5 and 172.8, 201.6 mg per 100 ml serum.

Considerations of plasma eorticoid variability in experimental design. R. W. Adkinson °, F. C. Gwazdauskas, W. W. Thatcher, C. J. Wilcox, and H. H. Head, University of Flori- da, Gainesville.

Experiments involving over 3,000 observa- tions on 349 animals characterized variances associated with plasma corticoid (ng/ml). Either corticosterone, cortisol or total corti- colds were measured. Data were analyzed by least squares models that included treatment, cow in treatment, and time to the highest order of significance. Coefficients of variation ranged from 26 to 90% with mean 57.1 and median 58.1. Animal and error variances for normal (noncystic) cows at basal corticoids were 3.0 and 30.6. Corresponding variances of corti- colds for normal cows at stimulated (post adrenocorticotropin) amounts were 11.2 and 233.3. Variances of corticosterone and eortisol for normal cows in response to stimulation were 26.7 with 121.2, and 1.2 with 3.5. Cortisol at basal and stimulated amounts for cystic cows was associated with animal and error variances of .61 and .31, and 35.5 and 36.9. Large error variances associated with corticoid point out the need for careful design of experiments and judicious selection of number of animals needed ¢o detect typical treatment responses.

Lacta~ional responses of ovariectomized cows to two hormonal induction schemes. S. Cha- kriyarat*, H. H. Head, W. W. Thatcher, K. C. Bachman, and C, J. Wilcox, University of Florida, Gainesville.

Fifteen ovariectomized dairy cows were in- jected daily with .1 mg estradiol-17fl and .25 mg progesterone per kilogram body weight. A partially balanced incomplete block design evaluated effects of 7 (Gronp I, n=7) versus 21 day (Group II, n-----8) hormone injections; adrenocorticotr~pin (200 IU) versus dexa- methasone (.028 mg/kg body weight) on days 11, 12, 13 after hormone injection; and single thyroid releasing hormone (100 ttg) iniectinns (IV) on days 1, 7, 17 (Group I) or 1, 7, 31 (Group II). Lactation was initiated sucessfully (>5 kg/day, X (4 wk) ----- 8.5 kg/cow) in 14 cows. Group II production was higher (P<.01) than Group I (10.63 to 6.83 kg/cow per day), and those receiving adrenocorticotrapin produced more (9.59 vs 6.67 kg/cow per day). Effects of thyroid releasing hormone on milk yield were positive JOURNAL OF DAIRY SCIENCE VOL. 58, NO. 1

only in Group II for injection day 31. Several significant interactions indicate the importance of hormone injection scheme and sequence on subsequent milk yield.

Hormonal induction of lactation in sheep. H. H. Head*, C. Delouis, M. Terqui, G. Kann, and J. Djiane, University of Florida, Gaines- ville, and Laboratoire de Physiologic de la Lactation, CNRZ, Jouy-en-Josas, France.

Twenty sheep were assigned among five groups and received injections of estradiol-17fl and progesterone (25 and 62.5 rag/sheep per day) for 7 days. On days 18, 19, and 20 the five groups received twice daily injections of: I, nothing; II, cortisol (25 rag); III, growth hormone (15 mg); IV, II and III; V, II, III and thyroxine (.5 mg). Hand milking was initiated on day 18 and machine milking on day 21. Twice daily blood samples were obtained from Groups I and IV for 35 days. Mean maxi- mal plasma estrogen and progesterone concentrations occurred between 5 and 12 days (14.6 and 7.15). Plasma corticoids were elevated during injection, and prolactin increased (to 1370 ng/ml) within 24 h after the first hormone iniection followed by a second peak 3 to 5 days later. Plasma prolactin increased as hormone concentrations declined (days 12 to 18). Within groups, lactation was initiated and sustained [mean daily yield (4 wk) > 200 ml/day] in 0, 2, 1, 2, and 3 sheep, respectively. Production was least in GroL~p I (87 ml/day) and greatest in Groups II and IV (270 ml/d%v).

Changes in mammary gland capacity in lactating holsteins. R. D. Mochrie, North Carolina State University, Raleigh.

Mammary gland capacity was determined by interrupting milking for 35 h. Capacity was taken as the combined volume of normal and complementary milk obtained at a 35-h milking. Capacities were obtained on nine first, eiKht second, and nine later-lactation Holste:ns whose 305-day production averaged 5.9, 7.0, and 7.7 10 ~ kg. Each cow was measured in wk 6, 22, and 38 of her lactat;on. Caoacitv averaged 15.0, 18.8, and 23.6 liters, for first, second, and later-lactations. The mean final capacity (38-wk) as percent of initial (6-wk) was 76, 66, and 58 with increasing lactation number. Corresoonding persistency values (PV equals last half lactation yield as percent of first half) were: 72, 64, and 62. Correlation of persistency with ratio of final to initial capacity was .70 and .74, .93 and .68 with increasing


lactation number. Complementary milk was correlated with persistency for first, second, and later lactations .75, .63 and .112.

Virginia's young sire program. Ronald E. Buffington, Virginia Polytechnic Institute and State University, Blacksburg.

Each year about one-half of the 159,000 grade-A dairy cows in Virginia are bred na- turally to unproven bulls. It becomes important to provide dairymen with a measure of genetic potential of these bulls. The objec- tive of the Virginia Young Sire Program is to ider~tffy genetically capabilities of young unproven bulls on dairy farms. Pedigree Index Certificates which include pedigree estimates of genetic merit have been sent to owners of 100 Holstein bulls since August 1, 1974.

The top 25 bulls have an average index of + 1062 milk and + 36 fat, the second 25 bulls have an average index o~ + 808 milk and + 29 fat, the third 25 bulls have an average index of +600 milk and +22 fat, but the bottom 25 bulls have an average index of + 174 milk and + 8 fat. All 100 bulls have an average index of +661 milk and +23 fat. Thirty-nine different bulls were used to sire these 100 bulls. Fifty-four dams were classified with an average score of 85.9 points, average cow index of +446 milk, and an average production per lactation of 8,661 kg of milk.

Dairy artificial insemination sire vital statis- tics. J. L. Kratz, C. J. Wilcox*, F. G. Martin, and R. B. Becker, University of Florida, Gainesville.

Records of 11,704 sires leaving service during 1939 to 1974 were analyzed. Frequencies of reasons for disposal were heterogeneous for breeds and countries. Culling frequency for Holsteins and Ayrshires for poor type of daughters was higher in Canada than the United States. Major reasons for disposal were undesirable characteristics of daughters (20.7%), reproductive performance (32.5%), disease and infect, on (13.9%), problems in collection (10.9%), injuries (4.2%), and others (17.8%). Frequency of culling for low production of daughters increased steadily, Period A, 1939 to 1949, 7.6%; B, 1950 to 1964, 11.8%; C, 1965 to 1974, 30.9%. Most sires departing were sold for beef, 83.9%; 8.2% died at the stud, and 7.9% were re~xned for service elsewhere. Average tenures, adiusted for age at entry, varied from 3.19 yr (Milking Shorthorns) to 3.69 yr (Brown Swiss). Ten- ures increased from Period A (2.00 yr) to B

(3.69 yr), with little change from B to C (3.58 yr).

Mineral composition and variability of Ken- tucky forages. G. S. Hess and R. W. Hemken, University of Kentucky, Lexington.

The nutrient content of 217 Kentucky forage samples was analyzed in the 1973-74 feeding season. Moisture, crude protein, crude fiber, calcium, phosphorus, magnesium, potassium, sodium, iron, manganese, copper, and zinc were determined. There was nearly a three-fold variation in crude protein content of corn silage and more than four-fold variation in crude protein of mixed mostly legume hay samples. Energy variation was significant but not nearly as large. Mineral content of corn silage was deficient over 65% of the time in both major and minor minerals with the excep- tion of manganese. Other forages showed a lower content in many major and minor minerals than expected. Feeding recommendation implications are examined.

Passage route into stomach compartments of liquid feeds consumed from a lick-wheel and effects of their abomasal infusion on plasma glucose. L. W. Whitlow, S. P. Marshall, and C. J. Wilcox, University of Florida, Gainesville.

Passage route was studied in three heifers in a 3 x 6 incomplete block design with six 7-day periods. Treatments were: A, control; B, liquid supplemer~t fed from a lick-wheel; C, supplement infused into retieulorumen; and D, cane molasses from a lick-wheel. Feeds were administered 30 rain prior to sampling contents o.f retienlerumen and abomasum, and 4 h prior to blood sampling. Recovery of dietary marker dissolved in liquid feeds from recticulorumen contents and concentration in abomasal ingesta provided no evidence of rumen bypass. Ammonia mad nonprotein nitro- ~en intake from administered feeds were high- lv correlated. Plasma glucose did not differ significantly. Influence of abomasal infusion was investigated in a 3 x 4 incomplete b~ock design. Treatments were: A, no infusion B, 35% crude protein liquid supplement; C, 20% of same and D, cane molasses. Cubic regression curves of treatmer~ts for plasma glucose versus time were not parallel indicating varied treatment rest~onses. C and D resulted in higher plasma glucose than A and B. Treatment B amounts were variable.

Reconstitution of coastal bermudagrass hay with water and anhydrous ammonia. G. T.

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Lane*, R, L. Botts, R. E. Liehtenwalner, and Rebecca J. Ahrens, Texas A&M University, College Station.

Two studies were to evaluate a silage additive containing anhydrous ammonia in pre- serving Coastal Bermudagrass haylage at varying moisture. One liter quantities of haylage containing O to 6% of the additive (20% nitrogen) and from 10 to 50% moisture were sealed and stored for 30 days. Hereford steers were used to determine digestibility and nitrogen balance of haylage containing 40 to 45% moisture and 3% additive (13.3% nitrogen), and haylage at 40 to 45% moisture and no additive, and hay at 10% moisture and no additive. The preliminary study indicated best results with 3% additive and above 40% moisture. Haylages above 40% moisture had a pleasing aroma and were readily accepted by animals. Apparent in vivo coefficients of diges- tibili, ty for all components were highest for haylage with additive, intermediate for 40% havlage with no additive, and lowest for the hay. Animals receiving hay remained in positive nitrogen balance while those receiving haylage were in negative balance.

Varying amount and method of feeding of a liquid protein supplement to lactating dairy cows. O. T. Fosgate, University of Georgia, Athens.

Preliminary trials using a commercial liquid protein supl~lement (Pro-Lix) indicated that lactating cows on ad lib all-in-one rations will voluntarily consume 1.1 kg/day liquid protein supplement. Four groups of 12 cows each were fed: Group A, a balanced 13% crude protein one ration; Group B, 11% one ration and .77 kg/dav liquid orotein supplement; Group C, corn silage, 7.26 kg concentrate, and .83 kg/ day supplement; Group D, corn silage and 7.26 kg/dav concentrate. Group B gave more milk and rat than Group D. but d;fferences between Grouos A, B, and C and Grouos A, C, and D were not significant. In a double reversal 12 cow~ consumed 5 17 k~ liquid protein and 40.2 k~ corn silage daily. The control ration was 27.2 kg corn silage, 7.26 kg concentrate; and .9 kg liquid pr~te;n. Differ- ences in yield were not significant. Ten cows were fed 24.9 kg/day of an all-in-one ration containing 15% lJouid protein for 305 days, ten cows were fed 27.2 corn silage, 9.1 kg concentrate and 1.63 k~/day protein, and ten cows, a mixture of 34.0 k~ corn silage, 6.8 kg concentrate, and 2.27 kg protein. Yields of fat- JOURNAL OF DAIRY SCIENCE VOL. 58, NO. 1

corrected milk were 6,644 kg, 6,419 kg, 6,913 kg.

Comparison of corn and forage sorghum silages supplemented with two quantities of protein. H. D. Baxter*, M. J. Montgomery, and J. R. Owen, University of Tennessee and ARS, USDA, LewLsburg.

Thirty lactating Jersey cows were in a 12 wk feeding trial to compare the following silages: (1) Silo fill 33A sorghum, (2) Funks 102F sorghum, and (3) Term 606 com. Concen- trate was fed at 1 kg for each 4 kg of 4% fat- corrected milk. One-half of the cows on each treatment had this daily concentrate allotment reduced by 1.36 kg which was replaced by an equal amount of soybean meal fed over the silage. Forage dry matter intake (percent body weight) and 4% milk (kg) production were: 2.09, 15.8; 1.76, 16.5; and 1.85, 17.1 for the various sihges without soybean meal and 1.96, 17.6; 2.06, 17.0; and 1.84, 19.0 with soybean meal. Corn silage was superior to both forage sorghums in actual milk and 4% milk production. Higher 4% milk production for soybean meal feeding was due to increased fat test. Yields of 30% dry matter silage for the three forages were 40.3, 48.9, and 38.1 metric tons per heotare.

Constant versus variable ratios of corn silage to concentrate in a complete feed for Iactating cattle. Howard van Dijk*, M. J. Morttgomery, and C. R. Holmes, University of Tennessee, Knoxville.

Thirteen pairs of Holstein cows were used to compare a complete feed in which forage to concentrate ratio was constant or variable during early part of lactation. Treatment 1 consisted of a complete feed of corn silage and concentrate blended in a 3:1 forage to concentrate ratio (as fed basis) and fed continuously throughout the experiment. Treatment 2 consisted of a variable forage to concentrate ratio of; 2:1 for 8 wk, 3:1 for 8 wk, and 4:1 for 8 wk. Cows were fed 2.27 kg of alfa]fa hay per day to prevent butterfat depression. Dry matter intake (percent of body weight) for the complete feed was 2.29, 2.31, and 1.96 for treatment 1 for the three periods. Similar data for treatment 2 were 2.36, 2.30, and 1.87. Milk production (kg), fat (%), and 4% FCM (kg) rer day for treatment 1 were 29.1, 3.51, 26.9; 27.1, 3.48, 24.9; and 23.7, 3.54, 22.0 for the three periods, respectively. Similar data for treatment 2 were 28.4, 3.46, 25.9; 26.0, 3.51, 23.8; and 21.6. 3.68, 20.5 for the three periods, respectively.


Metabolic mad lactational response to an ensiled complete ration. Glen D. O'Dell*, B. F. Jenny, J. C. Ellers, and C. J. Montgomery, Clernson University, Clemson, SC.

A double-reversal trial compared lactation response of two grot~ps of six Holsteins fed an ensiled complete ration or corn silage fed in feed lot and concentrate in milking barn as control. The concentrate was shelled corn (.445), citrus pulp (.25), soybean meal (.275), phosphate (.02) and trace mineral salt (.01). Dry matter at time of ensiling was .291 for green chop corn and .888 for concentrate. Mixing was a 5:1, silage:concentrate basis (dry matter ratio 62:38). Dry matter was 37.0% at ensiling and 38.7% after fermentation. Mean kg/day of milk production, fat corrected milk and dry matter intake were 22.9, 21.4, and 16.5 for ensilect ration and 24.5, 22.9, and 18.0 for control. Percents milk fat, protein, and total solids were 3.6, 2.8, and 12.0 for ensiled and 3.6, 2.9, and 12.1 for control ration. Metabolism and balance studies with 150-kg Holstein steers showed an increase in crude protein digestibility of the on- siled ration. Daily Ca, P, and Mg retention was similar. Nitrogen retention was higher for ensiled ration and sulfur retention greater f o r control. Total digestible nutrient§ were 68.1 and 62.3% for ensiled and control rations.

Roughage and l~rotein sources in maltlage- containing complete rations for lactating cows. A. W. Wright and K. R. Cummings*, Missis- sippi State University, Mississippi State.

An 88-day lactation study with 40 group- fed cows was to compare a conventional dairy ration of corn silage fed ad libitum (maltlage at 16.0 kg/cow per day) and a 20% crude orotein concen,trate according to production (1) with three complete rations. Complete rations contained 35.0 to 50.0% maltlage, a product consisting of wet brewers' grains, corn, and minerals. The complete rations were a blend of corn silage and 20% crude protein concentrate (2), corn silage, ground corn, and Pro- Lix (3) and cottonseed hulls and concer~trate (4). Rations provided similar amounts of fiber, r~rotein, and energy. Adjusted means o,f the four rations for 4% fat-corrected milk and per- centaqes of milk fat and protein were: (1) 23.4 kg, 3.84, and 3.54; (2) 20.9 kg, 4.02, and 3.60; (3) 22.2 kg, 3.74, and 3.62; (4) 24.7 kz, 3.77, and 3.80. There were no significant differences in mean fat percentage or mean body weight gain for the groups. Incomes above feed costs/cow per day were: $3.05, $2.80, $3.13, and $2.51 for the four groups.

Challenge grain feeding versus "all-in-one" feeding programs for lactating Holstein cows. L. L. Rusoff*, Cecil Branton, and D. L. Evans, Louisiana State University, Baton Rouge,

The records of 60 Holstein oows in the university herd which had completed lactations on two different feeding programs were compared on lactation response. The same animals were on a modified dry lot operation with a challenge grain feeding program (A) from 1963 to 1971 and changed over to a drv lot modified complete feed system (B) from 1971 to 1974. The laetatiorr means (two times 305- day mature equivalent), for milk production, percent milk fat, total fat production, and fat- eolTected milk during A were: 7,088 kg, 3.20%, 230 kg, and 6,289 kg; and during B: 7,374 kg, 3.75%, 27.6 k~, and 7,093 kg. B system of feeding was favored.

Intermediate type sorghum silage compared to corn silage for lactating dairy cows. B. L. Arnold, J. F. Beatty, and J. W. Daniel*, North Mississippi Branch Experiment Station, Holly Springs.

Four trials were ha separate years. Funk's 102F, or a similar predecessor, was the sorghum used in all trials. In Trial I, a double- reversal with sLx-cow groups of Jerseys, cows fed corn silage produced 15.1 kg 4% fat corrected milk daily, and cows fed sorghum silage produced 13.8 kg daily. In Trial II, a double- reversal with eight-cow groups of Jerseys, cows on sorghum had .78 kg cottonseed meal sub- sti, tuted for .78 kg grain; daily kg of milk for corn and sorghum was 14.6 and 14.3. Trial III was continuous with 17 pairs of Holsteins. Cows on sorghum had .78 kg soybean meal substituted for .78 kg grain. Dailv kg 3.5% fat- corrected milk 20.7 corn and 20.2 sorghum. In Trial IV, continuons with 20 pairs of Holsteins, sorghum silage was supplemented with .91 kg soybean meal daily. Daily kg 3.5% milk for corn and sorghum was 26.0 arid 24.3. Corn silage in Trial IV was disfiaaguished from the other three trials in that the grain yield was 8900 k~/ha and grain yield in the other three was 3000 to 4600 kg/ha.

Influence of vibrio fetus on reproductive efficiency and milk production in a Georgia dairy herd. J. N. Maddux* and D. J. Williams, Uni- versity of Georgia, Athens.

Progress in milk production was constant in a 150 cow Georgia dairy herd (4536 kg to

JOURNAL OF DAIRY SCIENCE VOL. 58, NO. 1


6638 kg) from 1963 to 69. During 1970-71 the rolling herd average declined 1540 kg. Vibrio fetus was diagnosed via laboratory study of the herd in 1970. Four manager- herdsmen were employed from 1969 to 72. Breeding efficiency varied as calving interval 13.0 to 16.1 m; breedings per conception 1.3 to 2.8; average days open 128 to 234; average days dry 54 to 92 and income over feed cost: $608 to $381/cow per yr. Good breeding management, routine vaccination, accurate reproductive records, and monthly veterinary ex- aminations of appropriate cows have each contributed to returning the herd to normal milk production via normal reproduction. The economic loss was more than .25 million dollars, and the herd required 5 yr for recovery.

Effect of a eoumaphos anthelmhaic on production and quality. J. F. Beatty, B. L. Arnold, E. W. Custer, W. H. McGee, and J. W. Daniels, North Mississippi Branch Experi- ment Station, Holly Springs, and Mississippi State University, State College.

A eoumaphos wormer (Baymix) was administered to laetating Holsteins to determine (1) its effect on milk production, (2) its effect on milk flavor, and (3) whether it contributed an inhibitory substance to the milk. Thirty-six animals were paired according to production, age, and stage of lactation and randomly assigned to a treated (28.5 g Bay- mix/45.4 kg per day for 6 days) or to a control group. The ration consisted of a 20% crude protein concentrate feed at 1 kg/3 kg of milk, corn silage ad libitum, and sorghum-sudan- grass pasture (4 h access/day) when available. Milk was sampled on the 4th day of treatment and on the 3rd day post-treatment for organoleptie and inhibition tests. Worming lactating animals with Baymix neither caused off flavors nor contributed any inhibitory substance in the milk. However, worming did not increase milk production during the 9 wk fol- lowin~ treatment and does not appear war- ranted for lactating dairy cattle fed under a similar regime.

National mastiffs protocols in testing the efficiency of a teat dip. D. L. Chowning, J. H. Nicolai, B. E. Langlois, and R. W. Hemken, Ur~iversity of Kentucky, Lexington.

The experimental procedure as outlined by the National Mastitis Council in Protocol A & B was used to test the efficacy of ID-14 Liquid Udder Guard against Streptococcus agalactiae. A total of 15 dry Holstein cows JOURNAL OF DAIRy SCIENCE VOL. 58. NO. 1

were selected for Protocol A which determines the effectiveness of a teat dip on the outer surface of the teats. The reduction in actual count of Streptococcus agalactlae after an exposure of i h to the teat dip was 98.4%. There were 88 quarters from 22 Holstein and Jersey cows chosen for Protocol B. Thirty-four quarters were dipped in ID-14, and 36 were used as controls in this experiment which ran for 14 wk. Nineteen Streptococcus agalactlae infections occurred in the trial with 14 in the non- dipped quarters. The actual reduction of intra- mammary infection was 62.2% for Streptococ- cus agalactiae. The ID-14 liquid Udder Guard proved effective in reducing new infections of Streptococcus agalactiae based on the methods and procedures outlined by the National Mas- titis Council.

Effects of simulated fallout radiation on laetat- hag cows. M. C. Bell*, L. B. Sasser, and J. K. Miller, University of Tetmessee, Knoxville.

To determine the effects of radioactive fallout on milk production, eight 500 kg Holstein cows were exposed to 120 R from cobalt-60, then fed 1 Ci of yttriurn-90 fused to 88 to 175 u sand particles. The treated cows compared with controls showed slight despression in white blood cells and platelets. Anorexia, reduced milk yield, and some diarrhea was observed in treated cows after 7 days. By day 30 in treated cows, feed intake and milk yield were 36% and 50% of control values. By 100 days treated c~ws had lost 21 kg while controls had gained 20 kg, and milk production of treated cows was 80% of controls. Weanling rats fed milk from these cows over 56 days were unaffected by treatment in contrast with Russian data. Two treated cows were killed and showed extensive damage in the ventral portion of the rumen and abomasum. These effects were not as severe as in 30 kg sheep and 180 kg calves fed similar concentrations of fallout simulant. Limited data show no carryover effects on reproduction and on the next lactation period.

Comparison of manual and automatic quarter take-off units on milk production and residual milk. J. H. Nioolai, Jr., R. W. Hemken, R. H. I-/atton, and F. S. Button, University of Ken- tuck-y, Lexington.

Twenty-four Holstein cows were in a double reversal experiment with 4-wk periods to de- terrnine effects of manual versus automatic quarter take-off milking machines on milk production and residual milk. For group I (auto-


marie-manual-automatic), manual milking decreased residual milk by .27 kg or 2,61% per milking. For group II (manual-automatic- manual), automatic milking increased residual milk by .17 kg or .93% per milking. Responses for milk yield and milk ~at conter~¢ were --.23 kg, +.09%; and +.06 kg, --.01% for groups I and II. The data suggest little difference in milk yield due to automatic or manual removal of milking machines.

Heat reflective paint for roof insulation in a free stall barn. B. F. Holloa*, D. O. Baxter, J. R. Owen, and M. J. Montgomery, ARS, USDA, Dairy Experiment Station, Lewisburg, TN, and University of Tennessee, Knoxville.

A 120-unit free stall barn facing south was divided into equal east and west sections. The galvanized roof and west, wall of the west section were painted with two coats of a commercial heat reflective paint, and the east section was left unpainted. Equipment was placed in each section and at an adjacent outside loca- tio~ to record ambient, temperature, humidity, and black bulb thermometer readings continuously for July 29 through September 15, 1974. Daily radiometer readings were in m/dafter- noon at five lecations inside each section of the barn. During 49 days there were 25 days when outside temperatures reached 29 C or above. The 25-day mean midafternoon readings for the painted and unpainted sections were: ambient temperature, 28 8 and 30.0 C; black bulb temperature, 29.4 and 32.8 C; radiometer read- ing on underside of south roof, 32 and 44 C; and humidity, 55 and 53%.

Quality of selected "natural state" stream waters of upper South Carolina. A. B. Bodine* and J. J. Janzen, Clemsoa University, Clem- son, SC.

Due to increasing interest in pollution of water systems and its concomitant effects on ecological balances, numerous standards have been established for surface waters. It seems likely, however, that in certain cases the standards are unrealistic or nonrepresentative. Therefore, research was undertaken .to evaluate the quality of stream waters that were chosen as essentially "virgin" eco-systems. The waters were sampled with sterile Jeb tubes and analyzed for dissolved ozygen bacteria, pH, temperature, chemical oxygen demand nitrate, phosphate, and residual solids. Only dissolved oxygen, pH and Escherichia cell have standards established for them. Variances have been estimated from pooling of like variances from a large sample (N=380) . Only E. cell

mean values were different from those speci- fied in Pollution Control Authority standards.

Feeding behavior of imported German Braun- vieh and Schwarzbunte cattle in a tropical en- viromnent. E. A. Olaloku* and G. A. Ologun, University of Ibadan, Nigeria.

Individual feeding behavior of four cows each of the German Brannvieh and Schwarz- bunte was ~bserved in eight 12-h eontinuo~xs recording trials during the dry season of 1973. The animals were stall-fed a ration of maize silage, offered ad libitum at 2-h ~tervals. The time spent eating, ruminating, drinking, and lying down by each animal was recorded. Braunvieh cows spent slightly more time eating, 305.8 rain as compared to 301.2 rain for Schwarzbunte cows. Schwarzbtmto cows spent more time ruminanting, 172.7 mir~ compared to 142.0 min for Braunvieh cows. They also spent more time drinking water, 8.4 min compared to 5.4 min for Schwarzbunte cows. German Braunvieh cows spent more time lying down compared to the Schwarzbunte cows, 120.4 min to 83.5 rain. Implications of these results are discussed in relation to adaptation of imported breeds and their management for milk production under the local environment.

Overview of milk production in the eighties. M. E. McCullough, Georgia Station, Experi- ment, CA.

The economic climate within which~ milk will be produced will be determined by (1) world cocnpetitioa in milk production, (2) world demand for feedstuffs, (3) competition between alternative foods, and (4) govern- mental farm policies and programs. This climate will influence the type and size of dairy enterprises and probably will result in more in- cerporated dairy units with professional management and fewer farmer owned artd op- erated units. Major changes in technology can seldom be anticipated. Predictions of the future are most frequently in error due to this inability to forecast major changes. In the ab- sence of a major breakthrough, changes likely will come about thro~lgh continuing improve- ments in production and marketing efficiency. The probable nature and influence of these economic and technological factors will be discussed in terms of conditions in early 1975.

Trends anticipated in beef cattle breeding. Marvin Koger, University of Florida, Gaines- v i l l e .

The major forces which govern the charac- JOURNAL OF DAIRY SCII1NCE VOL. 58, NO. 1


teristics desired in beef cattle include (1) the production systems in pl~oducing calves, (2) preferred weight and finish in slaughter cattle, and (3) sttpply and cost of grain. Increased awareness of opportunities for improvement and economic pressures will increase emphasis on high weaning rate in beef cattle. Im- proved maternal ability will be essential to re- tain rapid development with limited grain. The ability to maintain condition under pasture eenditions will be of increasing concern to breeders. Limited grain will promote cattle that finish well on short feeding periods. These pressures are expected to result in further changes in characteristics of the standard breeds thro~agh intensive selection, expansion of new breeds, and further extension of sys- tematic crossbreeding in commereial herds.

Beef market trends in the eighties. Lindsey H. Horn, Swift Fresh Meats Company, Chicago, IL.

Economic disasters in the cattle industry and impact of world demand for food in 1974 will cause the beef industry to rebuild on a revised and sounder basis. Cross breeding, performance testing, and growing feeder cat-tie to heavier weights on forage and roughages will become standard practices. Cattle will be fed less grain per head to finish and will be mar- keted as leaner animals. C~vernment grading standards will be changed to reflect the tender- hess in younger cattle without requiring exces- sive fat. Consumer demand will cause a much higher percentage of the beef to be fabricated or tenderized in some manner. It will take a larger cattle population on farms in relation to slaughter to keep the per capita consumption near current levels. This can be accomplished by utilizing the vast acreage suited only for pasture and roughage production along with by-products, particularly from grain crops. This should cause the ruminant animals, particularly cattle, to become an increasingly important source of food for the human diet.

Legumes versus applied nitrogen in the forage system. Vance H. Watson, W. R. Thompson, Jr., and W. E. Knight, Mississippi Agricultural and Forestry Experiment Station, Potash In- stitute of North America, and USDA-ARS.

Economical production of high quality forage is necessary for continued growth and suc- cess of the livestock industry in the South. Perennial grasses fertilized vdth large quantities of nitrogen often produced more dry matter and total digestible nutrients per hectare JOURNAL OF DAIRY SCIENCE VOL. 58, No. 1

than swards of grasses and legumes. However, recent price increases make the use of large quantities of nitrogen fertihzer or~ grass pastures questionable. Advantages for legumes in forage systems are (1) more even feed distribution, (2) forage production equal to that of grasses fertilized with 60 to 224 kg/ha of nitrogen, (3) improved conception rate of cows, (4) increased weaning weights of calves, (5) improved average daily gains, (6) help in prevention of grass tetany, (7) more rapid digestion than grass, and (8)stimulation of milk flow. Problems ,associated with production of legumes in the South include (1) acid infertile soils, (2) failure to use and properly apply specific strains of Rhizobium, and (3) poor fall production resulting from late plant- ing or failure to manage for early volunteer stands. Genetic and environmental effects on forage quality. Warren G. Monson, University of C, eorgia, Tifton.

Numerous research reports in the past dec- ade have indicated genetic control o~ forage quality factors. Development of techniques to assess quality factors on large numbers of samples has enabled .the forage breeder to identify superior plant material early in the breeding program. Studies with a number of species indicate that sufficient variation in digestibility exists to faeiltiate improvement through breeding and selection. Factors such as protein, fiber, and lignin are also important in forage quality, as are a number of "anti-quality" factors s~eh as tannin and alkaloids. Many of these are genetically controlled. The potential of a plant to produce quality forage can be improved; however, the environment in which it grows will determine to a large extent whether this potential is realized. Weather, management, insects, and diseases can all af- fect the quality and quantity of forage produced from any species. Improving forage quality through processing procedures. Donald Burdick and R. R. Spen- cer, Field Crops Utilization and Marketing Research Laboratory, ARS, USDA, Athens, GA.

Due to favorable climatic conditions abundant forage is produced in the South; however, much of this is either wasted or of low quality. In addition to traditional use as pasture, hay, and silage, forage can be processed into feed products o~ improved nutri- tive va/ue for part4cular classes of livestock. Physical means (air-classification) can be used to obtain a high earotene-xanthophyll "leaf


fraction" for poultry and a "stem fraction" which can be used as a roughage for .cattle or further processed. Chemical processing can be used to obtain earotene-xanthophyll extracts or protein isolates for monogastrics. Chemical treatment also can be used to improve the digestibility of forages for ruminants. Proc- essed forage, or fractions thereof, properly supplemented may be used in complete rations, cubed o1" pelleted, for ease of mechanical feeding. With the high cost of feed grains and protein sttpplements and increased consumer demand for more low-cost livestock products, more emphasis should be placed on forage as a multi-use resource in efficient livestock production.

Iodine metabolism by calves fed anlon-ex- change resin. J. K. Miller*, E. W. Swanson, W. A. Lyke, and W. F. Byrne, Comparative Animal Research Laboratory, Oak Ridge, TN, and University of Tennessee, Knoxville.

Iodine recycling as it may be affected by binding fix the gastrointestinal tract was investigated by feeding Dowex l-X8 anion-ex- change resin to 21 calves in three experiments. Each additional amout~t of resin fed from .3 to 3.5 g/kg body weight further increased fecal excretion and reduced urinary excretion from single oral iodine~131 and intravenous iodine-125 doses. Feeding 1 g resin/kg body weight to calves given daily oral or subcutane- ous iodine-131 doses increased daily fecal iodine-131 excretion three to five times and reduced both plasma and urinary iodine-131 below pro-resin amounts. At 24 h after the last dose, gastrointestinal tract contents of resin- Fed calves contained 40% less radioindine anterior to the ceoum but 77% more in He large intestine than controls. Resin reduced water- extractable radioiodine by 16% in rumen, 66% in abomasum, 40% in small intestine, 65% in cecum and anterior large intestine, and 74% in posterior large intestine contents. These re- suits indicate the probability of iodine deple- tion by a highly efficient iodine binder in the bovine tract.

Effectiveness of simple oral electrolyte fluids in treatment of diarrhea in prerumlnaling calves. E. D. Moore*, B. F. Hollon, H. H. Dowlen, R. F. Hall, and J. R. Owen, ARS, USDA, and University of Tennessee, Lewis- burg.

Thirty Jersey calves which experienced diarrhea were randomly assigned to one of three treatments at the onset of the condition. The calves were penned individually and were

under 30 days of age. Treatment i consisted of withdrawing all energy feeds for 24 h and administration of an electrolyte solution (15 ml of a one to one mixture of sodium chloride and sodium bicarbonate in a liter of warm water) by nipple pail morning, noon, and evening. Af- ter 24 h, hay and grain feeding was reinstated with gradual return to milk. Treatment 2 was identical to 1 except that electrolytes were equal parts by weight of sodium chloride, sodium bicarbonate and potassium chloride. Treatment 3 consisted of reducing milk ~take by one-half, administration o~ oral anti- diarrheal medicant, and no changes in hay and grain. In Treatments I and 2, ff the dimThea persisted, an anti-diarrheal medication was initiated after the 24 h fast. There was no significant difference between treatments in severity or duration of diarrhea; however, calves on Treatments 1 and 2 appeared less dehydi-ated.

Utilization of wheat silage supplemented with three sources of nitrogen for growing heifers. H. D. Baxter*, E. D. Moore, M. J. Mont- gomery, and J. R. Owen, ARS, USDA, and University of Tennessee, Lewisburg.

In a 12-wk drylo,t trial 63 Jersey heifers were group fed wheat silage supplemented daily with: (1) 680 g soybean meal per heifer mixed with the silage, (2) 97 g urea-583 g corn meal per heifer mixed with the silage, and (3) liquid protein supplement fed free choice by lick wheel. The heifers within each supple- merit treatment were allocated randomly to: (a) unwormed control, (b) Thibenzole, and (e) Tramisol. Total dry matter intake as percent of body weight and average daily gains (g) for each nitrogen source were: (1) 3.03, 544; (2) 3.07, 386; and (3) 2.82, 259. Body weight gains on soybean meal were greater than urea-corn meal which was greater than liquid protein. Ir~take of protein st~pplement declined 82% from the first to the last week of the trial. There were no significant differences between unwormed and wormed heifers.

Soybean hulls as the primary source of energy aM protein for herd replacements. A. H. Rakes* and D. G. Davenport, North Carolina State University, Raleigh.

Two 15-wk feeding trials were to determine the feasibility of using soybean hulls to supply all or a major portion of the energy and protein requirements for heifers. Iu the first trial 20 Holstein heifers averaging 242 kg were paired and assigned randomly to two treatment

JOURNAL OF DAIRY SCIENCI~ VOL. 58, NO.


groups. Group A heifers were allowed access to a self-feeder containing soybean hulls. The ones in Group B consumed hay ad libitum and 1.81 kg of concentrate daily, In Trial II Hol- stein heifers averaging 244 kg were assigned to the same feeding treatments as in Trial I. In the second trial some grazabIe fescue was available to beth groups. In the first trial Group A heifers consumed 10.02 kg/head per day of soybean hulls and gained an average of .75 kg daily. An average Group B heifer consumed 7.25 kg of hay and 1.81 kg of concentrate daily while gaining .79 kg. During Trial II animals in Group A consumed 6.37 kg of soybean hulls/bead daily and gained .87 kg. An average heifer in Group B consumed 5.2 kg hay and 1.81 kg of concenl~ate while gaining .72 kg daily.

Three housing systems for dairy calves with feeding regime comparisons. H. H. Van Horn, M. B. Olayiwole, C. J. Wilcox, and J. M. Wing, University of Florida, Gainesville.

A factorial experiment with 116 calves compared three housing systems (inside bedded stalls, outside portable pens, and elevated, slatted-floor pens with automated flush system for waste disl~osal), once versus twice daily feeding o.f milk, and four 16% protein calf starters (basic corn and soybean meal with 15 and 30%, 15 and 0%, 0 and 30%, and 0 and 0% cottonseed hulls and citrus pulp). Calves were weaned at 28 days of age and continued on experimer~t to day 84. Cumulative weight gains to 30 and 84 days for starters were 6.70, 37.53; 8.21, 48.74; 8.32, 38.57; and 7.20, 39.42 kg. Daily feed intakes were .43, 2.72; .55, 3.10; .38, 2.01; and .41, 2.45 kg. The 15 and 0% starter was superior by both measures. It was not possible to detect effects of housing~ feeding frequency, or interactions. Gains to 30 and 84 days for once and twice daily feeding were 7.82, 39.33, and 7.43 and 41.31 kg. The fiush system saved bedding and made feeding and care easier.

Comparison of liquid manure slurry and nilro- gen fertilization on orehardgrass pasture for dairy heifers. M. J. Montgomery*, B. J. Bear- den, and J. W. High, Jr., University of Ten- nessee, Knoxville.

Tea paddocks (.81 ha each) of Boone orehardgrass were fertilized with: (1) 56 kg of nitrogen/hectare in three split applications (four paddocks); (2) equivalent amoamt of nitrogen/hectare from liquid manure slurry JOURNAL OF DAIRY SCIENCE VOL. 58, NO. 1

(three paddocks); and (3) twice the manure application of treatment 2 (three paddocks). Holstein heifers were used at a stocking rate of three animals (330 kg)/heetare in 1973 and 3.3 animals (217 kg)/hectare in 1974. Salt, minerals, and water were provided all animals. Average daily gain (kg) and total carrying capacity (animals/hectare) were .81, 627; .82, 516; and .80, 617 for the three treatments for 1973. Similar data for 1974 were .65, 624; .65, 572; and .71, 674. These data indicate that with excellen~t forage manage- merit large amounts of liquid manure slurry can be applied to pastures with no detrimental effect on gain or carrying capacity.

Effect of dietary potassium percent on feed intake, milk yield, and milk and blood minerals in lactating dairy cows. R. J. Dennis mad R. W. Hemken, University of Kentucky, Lexington.

Fifteen Holstein cows (three gro~tps of five cows) were fed rations containing three dietary potassium percents (.46, .69, and .97): .97% to all groups for a 2 wk preliminary period; .46, .69, and .97% to the respective group for 10 wk; and .97% to all groups for 2 wk post trial. These rations contained an estimated 17.7% crude protein and 16.4% crude fiber. Cows were group fed the first 10 wk and individually fed the last 4 wk of the trial (the last 2 wk of the 10 wk period and the 2 wk post trial period). During individual feeding, changing from .46, .69, and .97% potassium to .97% potassium resulted in the following differences in kilograms average daily feed intake and milk production: 1.5, .3, arid .9; and .6, --1.1, and --.3. Body weight, fat, and solids-not-fat contents of milk, and blood serum and milk cations (sodium and potassium) were not significantly affected. There was no evidence of symptoms common in potassium deficiency.

Dairy cow differences in ability to digest cellulose. K. M. Autrey*, J. A. Little, and T. A. McCaskey, Auburn University Agricul- tural Experiment Station, Auburn, AL.

In experiments on factors influencing cellulose digestibility by cows, some cows appear to digest cellulose more efficiently than others. An experiment was designed to compare five high producing dairy cows (mean mature equivalent 7960 kg) with five relatively low producers (6110 kg) in their ability to digest cellulose of two forages, Coastal bermuda hay and BR-79 sorghum silage. The mean daily milk production at the time of the experiment


was 22.6 kg for the high group and 11.3 kg for the low producers, The in, vitro arti~cial rnmen teclmique was used. The inocuhtm of test cows was obtained by stomach tube and pump via the esophagus. Mean cellulose digestion coefficients of hay and silage were 48.5 and 43.1% for high producers; 47.1 and 40.7% for low producers. The difference was more pronounced when the in vitro was done with composite inoonla of the five high and the five low producers.

Dried hemi-eellulose extract in pelleted concentrates for lactating dairy cows. R. W. Hem- ken*, H. D. Radloff, and D. R. Jacobsen, Uni- versity of Kentucky, Lexington.

Twelve lactatirtg Holstein cows were assigned to one of three pens. In a 3 X 3 Latin square design, treatment groups of four cows were fed rations with concentrates containing (1) no extract, (2) 2.5% extract, and (3) 7.5% extract. Concentrate mixes of corn, soybean meal, dried molasses, and minerals were pelleted with the hemi-cellulose extract replac- ing an, equal amount of dried molasses. The concentrate was mixed with corn silage and fed at five parts corn silage to one part concentrates. Treatment periods were 4 wk. Dry matter intake, milk production, milk fat, milk total solids, and solids-corrected milk in kg per day were 18.2, 21.5, .72, 2.6, 19,5; 18.1, 20.7, .74, 2.5, 19.4; and 17.1, 20.3, .71, 12.4, 18.8 for treatment groups 1, 2, and 3. Extract 2.5% is equal to molasses; however, 7.5% decreased feed intake and milk production.

regression analyses showed that fat corrected milk was positively influenced by both concentrate energy intake and percent days in milk. For each Meal of concentrate energy intake, increase in milk yield was .36 kg. Non- sigrtifieant variables were silage energy, intake, hay energy intake, rate of forage feeding, and herd size. The coefficient of determination (R 2) was 41%.

Relationship between ration and cholesterol in milk. George E. Hawkins, Auburn Univer- sity Agricultural Experiment Station, Auburn, AL.

Three trials were conducted with 10, 8, and 4 cows per treatment to evaluate effect o,f ration fed to dairy cows upon cholesterol in their milk. In Trials 1 and 2, cows on harvested roughage were fed a blended ration (16% crude protein) and those on pasture were fed a 17.5% crude protein concentrate and grazed ryegrass-clover (Trial 1) or sorghttm-sudan hybrid (Trial 2). In Trial 3, the cows (four per ration) were fed 15, 20, or 25% crude protein rations. Daily milk per cow in the three trials averaged 23.4, 23.8, and 25.3 kg. Choles- terol in mR/100 ml milk were: (1) blended ration 11.7, pasture 9.9; (2) blended ration 10.9, pasture 9.4; and (3) 15% crude protein 10.1, 20% 10.0, and 25% 9.5. Cholesterol in the 71 milk samples were correlated ( r : .62) with milk fat. Mean milk fat was 3.2% (range 2.0 to 4.1%). Only in Trial 2 did cholesterol adjusted for milk fat differ.

Relationship of energy to milk production of cows in Louisiana. A. D. Calub, L. L. Rusoff*, D. C. Huffman, and K. L. Koonce, Louisiana State University, Baton Rouge.

Herd month records from the Dairy Herd Improvemer~t Association in Louisiana from 1971 through 1972 were used to evaluate the relationship of estimated net energy intake and other management variables with milk production on a herd basis. Averages were 94 cows/ herd; 500 kg liveweight/cow; dairy milk production 13.18 kg of 3.75% fat; and fat corrected milk 12.72 kg. Average energy intakes (Meal/cow per day) by feed sources were concentrates 10.0; silage, 1.7; hay 1.4; and pasture 4.7. Concentrates supplied 56.0% and roughages 44.0% of the total est'mated net energy intake. Ronghages consisted of 9.6To silage, 7.8% hay, and 26.4% pasture. Multiple

Survival of salmonellae in ensiled feed con- raining bovine waste. T. A. MeCaskey and W. B. Anthony, Auburn University, Auburn, AL.

Feed consisting of 45 parts ground shelled corn, 15 parts corn silage, and 40 parts of manure collected from steers o~ a concrete floor was inoculated with 27 salmonellae cultures and ensiled in plastic bags. The cultures were not recovered from the feed after ensiling for 3 days at 25 C whereas 25 of the 27 cultures were recovered from inoculated manure. Manure with a pH of 6.0 to 6.5 prior to inocu- lation permitted 25 of the 27 enltures to sur- vive 3 days whereas none of the cultures survived in manure with an initial pH of 4.0 to 4.5. Ensfling tempera~re had a pronounced effect on salmonellae survival. With an improved recovery technique 21 of the 27 salmonellae were recovered from feed ensiled 4

JOURNAL OF DAIRY SCIENCE VOL. 58, NO. 1


days at 5 C, 25 from feed ensiled at 15 C, one at 25 C, and none were recovered from feed ensfled at 35 C. The pH of the feed e~siled ~t 25 or 35 C was lower than for feed ensiled at 5 or 15 C. C~liform count of the feed decreased from 1 X 107/g to less than 100/g at 35 C and decreased to 1 X 10~/g at 5 C.

Quality comparisons of four bermudagrass cultivars. C. R. Montgomery, B. D. Nelson, Marvin Allen, and Lee Mason, Louisiana State University, Franklinton.

Four bermudagrass cultivars (Cynodon dactylon (L.) Pers.), Coast-Cross, Alecia, Coastal, and Common were grown under uni- form management conditions and harvested at 28 day intervals (May to September). Quality measurements included intake and digestibility with sheep, in vitro digestible dry matter, and chemical composition (fibrous constituents and crude protein).

Intake of the forage on a season average ba-

sis ranged from 3.11% body weight with Coastal to 2.66% with Alexia. Atecia exhibited a lower seasonal average in vivo digestible dry matter (53%) as compared to other forages (56%). In vitro digestibility values for Alecia were the lowest while average cell wall constituet~t percer~tage for the season for Ale- cia was higher than the other cu~tivars. Inter- actions were obtained between forages and date with all measuremellts. Crude protein cor~te~t varied from a high of 16.7% with Coast-Cross to a low of 13.3% with Aleeia. Crude protein values were highest in Septem- ber.

Effects of fermentation 4ime o n in vivo/in vitro digesta%le dry matter relationships. B. D. Nel- son*, C. R. Montgomery, and Lee Mason, Southeast Louisiana Dairy and Pasture Experi- ment Station, Louisiana State University, FrankIinton.

Abstract not available at time o~ publication.

JOURNAL OF DAIRY SCIENCE ~OL. 58, No. 1

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