meat growth Flashcards
how to work out dressing out percentage
DO% = Carcass weight/Liveweight x 100
dressing out percentage differences between lines
Decreased with greater gut fill
Decreased for pregnant animals
Decreased for weaned vs. milk-fed lambs
Generally decreased for entire males
intramuscular marbling
fat inside the muscles as visible speckles of fat when concentration i high enough
subcotaneus fat
fat directly under the skin and over the muscle
intermuscular
difficult to trim if excessive quantities
genetic influence on the four key growth characteristics
growth rate
- efficiency of growth
- extent of growth (mature weight)
- compostion of gain (less then for the other traits)
cross breeding
results in heterosis where the performance of the cross breed is better than that of the parents.
compensatory gain
animals that have been previously underfed
grow faster than animals that were previously adequately
fed when offered the same feed allowance in a subsequent
period
lower in
- young animals
- restriction to severe
- feed levels restricted on subsequent period
Growth promotants
a non-medical or nutritional substance that affects the growth of an animal.
has trade restrictions etc
they are rumen active substances or steriods
other effects on growth
animal health
- stress
- climate extremes
- hours of daylight
- topography and shade
how promotants are applied (3)
- subcutaneous implant
- inclusion in feed
- slow release capsule in rumen
what are bones for (4)
- provides a rigid structure for muscle to attach to
- protection of vital body parts
- storage site for calcium and phosphorus
- production of new blood cells
adipose tissue function in living animal (4)
- energy store
- protects important organs
- subcontanous fat insulation
- provides high level of heat through thermo genisis
skaletel muscle functions
- movement
- heat production e.g. shivering
- source of nutrients if intake is to low
the animals in order of greatest to least dressing out percentage
pigs, paultry, lamb
how to tell the difference between a mature animal and an immature animal
as an animal metures it has more abominal muscle than leg muscle. the value of high proportion of meat decreaseswith age
carcuss clasification based largely on what type of fat
subcutaneous fat depth
-so greater or fewer proportions of fat here may effect carcass grading and hence payment
factors effecting meat quality
- tenderness
- colour
- flavour
- juiciness
factors effecting tenderness
more conective tissue= tougher
- ultimate PH of below 5.8
- aging of meat
- greater marbling may effect tenderness
factors of colour of meat
Myoglobin is a red-coloured compound
- more myglobin=redermeat
- high ph darker meat
what is rigourmotis and what causes it
- loss of muscle extensibility
- when ATP is depleted rigour mortis sets in
flavour
most differnces in the fat
-not very well understood
high ph =more bland
juiciness
- greater water content=more juicy
- more intramuscular fat more juicy
what is classification
- sorting of like with like
- different classes receive different payments to indicate which is more desirable
