TroutWalter Salzburger:
brown trout
Salmo trutta (forma fario)
Occurrence: Europe (part. Asia)
habitat: rivers, lakes
Max. size: 140 cm (f. lacustris)
Max. weight: 50 kg
Max. age: 38 years
Note: there are various forms, e.g. lake trout (f. lacustris) or marmorated trout (f. marmorata)
rainbow trout
Oncorhynchus mykiss
Occurrence: N-America (pacific)
habitat: rivers, lakes
Max. size: 120 cm
Max. weight: 25,4 kg
Max. age: 11 yeras
Note: since 1880 introduced in Europe and later also elsewhere
Exercise:1. How many fins are there in the trout? Which are paired/unpaired?
2. How many fin-rays are in the dorsal and caudal fin, respectively?
3. How many scales are along the lateral line? What are the rings in a scale?
Drawing I:
‣ Draw the trout
‣ mark the following features: mouth, nose, eye, operculum, lateral line, after, fins. mouth
eye
pectoral finventral fin
anal fin
dorsal fin
gill slit
operculum adipose fin
caudal fin
after
kidney
Drawing II:
heartlivergills
stomachgut
gonad
adipose fincaudal fin
dorsal fin
nose
swim bladder
after
anal fin
ventral finurinary bladder
lateral line
Exercise:1. Which is the organ next to the liver?
2. Is there a connection between kidney and urinary bladder?
3. Find the abdominal membrane (Septum transversum)
Heart and circulation
Exercise:1. Check the thickness of the wall of atrium and ventricle
2. Where is the ventral aorta?
‣ dissect the heart
‣ find the dorsal aorta
‣ longitudinal section through the heart
heart (A), atrium (1), ventricle (2), Bulbus arteriosus, Truncus arteriosus (3)
Drawing III: Brain
‣ 1. open the neurocranium (e.g. with a scalpel) and dissect the brain
‣ 2. draw the brain
Exercise
1. find the labyrinth with the semicircular canals
2. preparation of otoliths
Otolith
lateral line
‣ raise a scale with along the lateral line (with the forceps)
‣ lift the skin with a small cut
‣ the channels of the lateral line lie below the whitish skin layer...
Exercise:1. Find the Nervus lateralis. It is a side branch of the Nervus vagus and runs
below the later line
NV
CuEpP
S
De
Cupula (Cu), Dermis (De), Epidermis (Ep), nervous filament (N), Pore (P), scale (S), Nervus vagus (V)
Drawing IV: Cross section
Exercise:1. Where is the vein and the artery?
2. Which structures are paired/unpaired?
PeritoneumCoelomgutgonadkidneyribvertebra
muscle
dorsal fin
spinal cord
‣ make a cross section through the trout
‣ draw the cross section
skeleton