L6: Intro to Beef Cattle Population Med (Rae) Flashcards
(32 cards)
how many head of beef cattle in US
95.5 million (35m of which enter food chain each year)
beef prod. phases
cow-calf stocker-grower finishing/fed cattle (consumption) *total process takes 14-22mo.*
cow-calf phase
- minimal resource inputs
- “grass harvesting”
- calves raised to weaning (7-9mo.)
stocker-grower phase
- calves purchased and fed high forage ration (grass harvesting or small grain gleaning)
- minimal resource inputs
- growing phase (8-15mo.)
finishing phase
- intensive confinement operation
- fed mixed concentrate ration
- 90-150d
Bos taurus breeds
angus simmental shorthorn charolais hereford
Bos indicus breeds
Gir Nelore Guzaret American Brahman Sahwal
Santa Gertrudis =
shorthorn + Brahman
Beefmaster =
Brahman, shorthorn, hereford
Brahman hump***
hypertrophy of rhomboideus trapezius m.
FL calving/breeding/weaning seasons
Calving: Jan-March
Breeding: April/May
Weaning: Sep
maternal traits essential for beef cattle***
-must bond quickly w/o maladjustment
uniformity of:
gender frame and weight breed-type processing immunization
health management toolds
ID husbandry nutrition immunizaytion parasite control
immune system of bovine neonate
- immune competent
- usually devoid of active immunity
- dependent on primary and non-spec. defenses until passive transfer of immunoglobulins through colostrum
immunizing vehicles
KV MLV (altered virulence) IN (temp. specific) non-replicating MLV (temp. specific) killed bacteria (bacterin) live bacteria (altered virulence) toxoids (chemically inactivated toxic products)
see graph slide 33/35
:)
factors influencing maternal Ab interference
- virus type
- lvl of existing maternal Ab
- vaccine Ag and vaccine preparation (passage)
- route of admin
parasite burden dependent on:
age weather env. stocking rate (cattle density) pasture mgt parasite type
CS of CLINICAL parasitism
diarrhea anemia sunken flanks rough coat bottle jaw
effects of SUBCLINICAL parasitism
- greater dz susceptibility
- extra days to market
- inc. time to breeding
- suboptimal performance (reduced weight gain, milk prod, conception rates)
strategies for parasite control
- minimize pasture contamination: de-worm at start of grazing season and before egg shedding occurs; time therapy to seasonal grazing patterns
- balance stocking rates
- rotate pastures
cow procedures at mid-year animal evaluation
Brucellosis test
Johne’s test
when is parasite control done in cows
pre-breeding, post-breeding, pre-calving. NOT during breeding