Perugia, June 16th 2017 22nd Congress of A.S.P.A.

transcript

Environmental impact of animal production

Perugia, June 16th, 2017 – 22nd Congress of A.S.P.A.

G. Matteo Crovetto e Stefania Colombini

Luca Malagutti(Ω June 9, 2017)

World human growth

1960: 3.5 billion people; today: 7; in 2050: >9.

Today 50% of world people live in cities; in 2030 60%; in 2050 ??

A laid table for all the people of the world would be 2.8 million km long (7.5 times the distance Earth-Moon): quite a problem to feed everyone! (Pulina, 2011)

To produce food, crop and livestock systems need soil and water, both limited and diminishing resources.

G.M. Crovetto, Perugia 16-6-2017

World rural and urban population (1960-2050) (FAO, 2013)

Mission of agriculture and livestock systems

1° Supply food.

2° Preserve the environment.

For thousands of years man cultivates fields and rears animals for food.

Livestock systems: transform vegetable protein and fibre into animal protein of high nutritional value.

Animal kingdom: no fibre food of very high digestibility.

Food of animal origin: high nutritive value.

Meat, fish, eggs, milk and cheese supply man with essential nutrients hard to get from only vegetable-based diets. Among these:

essential amino acids (lysine, methionine, threonine, tryptophan, leucine, isoleucine, phenylalanine, histidine and valine)

essential fatty acids (e.g. ω3 and CLA)

minerals (e.g. Ca, P, Mg) and vitamins (e.g. B12)

Assets of food of animal origin

Contribute (%) of food of animal origin to human diet

Available protein and animal protein supply in the period 1990-2009 (FAO, 2013)

Which type of crop and animal production systems?

Basically 3 main systems:

Extensive (normally small-scale, family farming)

Semi-intensive (medium scale, group farming)

Intensive (large-scale, industrial farming)

Extensive systems rely on pasture (for ruminants) andscavenging and kitchen waste for monogastrics. Crop by-products

can be fed both to ruminants and monogastrics.

Intensive systems have high stocking rates and supply feeds heavily

or totally risk for the environment.

Strengths and weaknesses of animal production systems

Extensive systems: very low costs and normally low levels ofproduction. 1-2 billion people rely on these systems for theirfood supply.

Intensive systems: high inputs and costs, and highproduction levels. The majority of the world populationdepends on these food supply systems. However: risk of

negative environmental impact.

Efficiency must be improved in both systems to attaineconomic and environmental sustainability.

Environmental impact should be assessed per kg product(meat, milk, eggs, fish) more than in absolute values.

Which are the most efficient animals?

100 kg feed (madeby 80% cereal grainand 20% proteinsuppl.) can produceabout:

45 kg chicken

35 kg pork

15 kg beef

chicken pork beef

For fibre: ruminants (cattle, sheep and goats, buffaloes, camels).

For starchy feeds: monogastrics (pigs and poultry).

kg meat from 100 kg feed

Maintenance, a fixed cost to be amortized

Factors involved in the process of sustainable ruminant

production to feed the planet (Pulina et al., 2017)

The environmental sustainability of food production

depends also on the types of human diet

Mean dietary GHGEs per 2000 kcal for high meat-eaters (>100 g/d; n=8286), medium meat-eaters

(50–99 g/d; n=11971), low meat-eaters (>0 and<50 g/d; n=9332), fish-eaters (n=8123),

vegetarians (n=15751), and vegans (n=2041) in the United Kingdom (Perignon et al., 2017)

Types of diets and human health

Prudent diets with plenty of fruits, vegetables, nuts, legumes, and unrefined cereals and adequate amounts of meat, fish, and dairy products have also demonstrated beneficial effects on health (WHO-FAO, 2003).

In addition, avoiding animal products does not necessarily provide health benefits (Key et al., 2006).

Animal products are sole providers of some essentials nutrients, so that restrictive and monotonous plant-based diets may result in nutrient deficiencies with deleterious effects on health (Millward and Garnett, 2010).

Types of diets and human health (cont.)

The harmful impact of animal-based products on human health is only documented for processed and red meat at intakes higher than 50 and 100 g/d, respectively (IARC, 2015).

Moreover, the higher rate of mortality and chronic disease associated with Western diets is due not only to a high content of red and processed meat but also to excessive consumption of refined cereals, fried foods, soft drinks, sweets, and energy-dense, nutrient-poor food products.

IARC= International Agency for Reseach on Cancer

Effect of five diets on GHG emissions (Tilman and Clark, 2014)

Protein conversion ratios of livestock production systems (Tilman and Clark, 2014)

Global warming potential for livestock products, in CO2eq

expressed per kg of product (de Vries and de Boer, 2009)

Contribute (%) of different species to global CO2

equivalents emissions from livestock (FAO 2013)

98 8 6

Global emission of CO2 equivalents per kg of protein from different sources (FAO 2013)

From poultry and pigs less GHG/kg protein than from ruminants

Biomass use efficiencies for the production of edible protein from beef and milk for different production systems and regions

of the world.(Herrero et al., 2013. From IPCC 2014)

GHG emissions intensities of selected major agriculture, forestry and other land use commodities for decades 1960s – 2000s.

As agricultural and silvicultural efficiency have improved over recentdecades, emissions intensities have declined.

Whilst emissions intensity has increased (1960s to 2000s) by 45% for cereals,emissions intensities have decreased by 38% for milk, 50% for rice, 45% forpig meat, 76% for chicken, and 57% for eggs.

(FAOSTAT 2013, from IPCC 2014)kg CO2eq/kg or m3 product

Productivity and emission intensity

A large potential to mitigate emissions exists in low-yield ruminant production systems.

Improved productivity at the animal and herd level can lead to a reduction of emission intensities while at the same time increasing milk output.

Environmental impacts (%) per unit of product of concentrate-based

relative to roughage-based beef production systems (de Vries et al., 2015)

GWP=global warming potential; AP=acidification potential; EP=eutrophication potential.

Carbon footprint of conventional and organic beef production

systems: an Italian case study (Buratti et al., 2017)

CONVENTIONAL and ORGANIC=18.2 and 24,6 kg CO2eq/kg LW, respectively

In ORG farm, the longer

finishing period and type

of diet caused the

higher enteric

fermentation and manure

management emissions,

despite

the advantage of the

absence of synthetic

fertilizing that allows a

low impact for feed

production.

Environmental impacts of Italian beef production: a comparison

between different systems (Bragaglio et al., 2017)

CCI= Cow-Calf Intensive (cow-calf operations, with specialized beef animals constantly kept

in confinement)

FS= Fattening Systems (high grain fattening of specialized beef breed imported calves)

PoS= Podolian system (cow–calf operations, with Podolian cattle maintained on pasture and

finished in confinement.

SE= Specialized Extensive (specialized beef cattle maintained on pasture and finished in

confinement)

Functional unit: 1 kg of live weight of marketed beef cattle.

Environmental impacts of Italian beef production: a comparison

between different systems (Bragaglio et al., 2017)

GWP of light and heavy pig production from LCA studies(adapted from Bava et al., 2017)

GWP of heavy pig production from LCA studies: contributions of

different activities to environmental impact categories (Bava et al., 2017)

Daily nitrogen (N) balance of pigs at 152 kg BW (Galassi et al., 2010)

C=control; HF=high fibre; HFLP=high fibre-low protein.

Protein content (g/kg as-fed basis): C 120, HF 122, HFLP 98

Effects of dietary protein and essential amino acid content

on N balance in pigs of 129 kg BW (Galassi et al., 2015)

CONV=conventional diet; LP1=low protein and low essential amino acids diet; LP2=low

protein and conventional essential amino acids diet.

CP and Lys (g/kg as-fed basis): CONV: 132-5.5; LP1: 104-4.3; LP2: 97-5.1

Energy yield from forage systems in Lombardy (Zucali et al.,

Cornsilage It. ryegrass Corn grain High moisture HM ear Perm. mead. Lucerne

silage + CS dried shelled corn corn hay hay

GHG and forage systems in Lombardy (Zucali et al., 2014)

Cornsilage It. ryegrass + CS Corn grain dried High moisture corn HM ear corn Perman. meadow hay Lucerne hay

Forage systems for milk production in the Po plain

Base forage: mainly corn silage high DM and NE yield,

but also high economical and environmental costs (water,

GHG, fertilizers, pesticides, …) and need to purchase

protein supplement (e.g. soybean meal LUC, GHG, …

(Battini et al., 2016)

Nowadays there is more attention to permanent meadows

for their very low cost and their ability to improve C sink

in the soil.

Replanting grasses in lands previously sown with annual

crops can result in a significant increase in soil C, and in

some cases the soil C gain more than offset all the GHG

emissions from the farming system (Guyader et al., 2016).

LIFE Project “FORAGE4CLIMATE”

LIFE4CLIMATE aims to demonstrate that the forage systems connected to milk production (dairy cattle and small ruminants) can contribute to climate change mitigation in terms of:

Reduction of GHG emissions per kg milk

Increase of soil carbon stocks

through:

Proper choice of forage system

Adoption of Good Practices

Use of simple tools for the evaluation of C stocks and GHG emissions

Forage systems for less GHG emission and more soil carbon sink in continental and mediterraneanagricultural areas

Milk productivity and emission intensity (FAO 2013)

Nitrogen in milk and protein content of the diet

Dietary Crude Protein (% on DM)

(Crovetto and Colombini, 2010)

Nitrogen in milk and dairy efficiency

Dairy efficiency (kg milk/kg DM intake)

(Crovetto and Colombini, 2010)

Methane production and dry matter, starch and NDF intakesin lactating cows (Colombini et al. 2015)

Higher CH4 emission with NDF than with starch.

Starch

NDF DM

Methane emission per kg DM intake and milk yield

Pirondini et al., 2015.J. Dairy Sci. 98: 357–372

Open circuit respiration chamber

High yielding dairy cows produce less methane/kg milk

40 kg milk/d 20 kg milk/d 20 kg milk/d

148 kg methane/year

(11,7 g CH4/kg milk)

234 kg methane/year (+58%)

(18,6 g CH4/kg milk)

Less N to the soil and /kg milk from high yielding cows

40 kg milk/day 20 kg milk/day 20 kg milk/day

99 kg N to soil/year

(7,8 g N to soil/kg milk)

157 kg N to soil/year (+59%)

(12,7 g N to soil/kg milk)

Cradle-to-farm-gate emissions of 45 typical farms(Hagemann et al., 2011)

Total environmental impacts per kg of FPCM for 28 Italian dairy farms and on-farm contributions (Bava et al., 2014)

Numbers of studies showing positive, negative or mixed/no difference when

species abundance and/or richness where compared in organic versus conventional farming (Tuomisto et al., 2012)

The key challenges in conventional farming are to improve soil quality (by

versatile crop rotations and additions of organic material), recycle nutrients and

enhance and protect biodiversity.

In organic farming, the main challenges are to improve the nutrient management

and increase yields.

Also non-milk producing animals contribute to GHG emissions

A balanced breeding strategy optimizing milk production capacity

while minimizing the number of non-milk producing cattle is

important with regard to minimizing emissions from dairy

production systems.

For example Weiske et al. (2006) found that a reduction of 10% in

replacement rate, combined with a strategy to sell surplus heifers

at birth, reduced total emissions by 10%.

Relative distribution of wasted mass and wastage CF for five supermarket departments studied (Scholz et al., 2015)

Over a three-year period, 1570 t of fresh food (excluding bread) were wasted in the

supermarkets. The associated total wastage CF was 2500 t CO2eq.

Share of wastage carbon footprint (CF) and wasted mass of the meat total waste (BF = bone-free) (Scholz et al., 2015)

Conclusions

Protein of animal origin can positively integrate a vegetable-based

human diet.

Natural meadows and pastures are to be utilized through ruminants

protein from fibre. No other use of these lands.

Extensive and family farming systems must be maintained (human

presence, land protection, less urbanization), but their efficiency must

be improved.

Semi-intensive and intensive livestock production systems are

essential for food supply and should not be demonized, but must

minimize the environmental impact through genetics,

nutrition&feeding, and management.

Perugia, June 16th 2017 22nd Congress of A.S.P.A.

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