ANSC 313 Lecture Notes - Lecture 11: Weaning, Cattle, Umber
COW PROJECT!
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Range!
you have limited pasture/ range!•
cow herd should be 45-55 at all times ( breeding females)!•
most beef cattle put out on pasture for the summer!•
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environmental conditions!
weather and harsh climatic conditions are not the same on all ranches!•
this variable is unpredictable and can not be changed!•
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mating designs!
best to best - top calved "better" ( purebred to get the best calf)!•
best to worst - more uniform calf crop!•
random- maintain current diversity ( for rare breed)!•
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Crossbreeding or line breeding!
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line breeding/ inbreeding ( in later generations since bull progeny will be kept!•
more common in purebred show cattle, with bulls sold from the ranch!•
not allowed to buy new bulls!•
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"clean-up" bulls!
typically ranches might use clean up bulls that are put with the cows after the "desired' sires •
are removed!
not used in your operations !•
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bull must be bred to at least one cow to remain in your herd!•
typical herd would have 1 bull/ 20-30 cows!•
may want a "spare" bull, bred to one cow!•
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Cow herd!
"mature" cows comprise your original 50!•
ranch names assigned randomly!•
i.e. if you want to consider them another breed or crossbred, fine!◦
mate all cows for very first time!•
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CALVING:!•
not all cows will produce a live calf!•
some calves will die of an autosomal recessive disease!•
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calving!
not all cows have a calf!•
can't separate lack of conception from abortion!◦
occasionally calf print will say " lethal recessive disorder"!•
then you should consider implications to parents, relatives!◦
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Cow herd!
after calving the first time, most cows are mated again to maintain a breeding herd of 45-50!•
