Dairy Cattle Flashcards
Bos taurus
European Origin; Adapted to cooler climates
Pasteruization
treating a substance with heat to kill or slow the growth of pathogens
History of Dairy Cattle
Domesticated 18,000 years ago near the boundary of Europe and Asia
Bos Indicus
Indian Origin; Adapted to hot climates
Tuberculosis (TB)
infectious disease caused by Mycobacterium tuberculosis; lungs usually are involved, but any organ in the body may be affected
artificial insemination
-Acquisition of high-quality semen from a bull
-Detection of estrus in the female
or
-Synchronization of estrus &/or ovulation
-Deposition of semen properly in the female’s reproductive tract
-Now: >66% of dairy cattle farms rely on AI
Trends in U.S. Dairying
- Fewer dairy farms with larger herds of cattle.
- Increasing milk production per cow.
Dairy products roughly provide how much percent of annual cash receipts from agriculture in the U.S?
10%
How much beef is consumed in the U.S comes from cull dairy cows, dairy steers, and calves?
22% of Beef
export volume
12 to 18% of production during the 2010s
Small Herds
-Family-owned
-Family-operated
-Grow own feed
-Raise own youngstock
-House cows in barns or on pasture
Large Herds
-Family-owned
-Hired-labor
-Grow & purchase feed
-Raise own youngstock or
contract to raise off-site
-House cows in barns or
drylots
Dairy Breeds
- Holstein
- Jersey
- Brown Swiss
- Guernsey
- Ayrshire
+/- 6. American milking shorthorn
Life cycle of a dairy cow
1) Calf
2) Heifer or Bull
3) The heifer would either calf or become a lactating Cow
4) the lactating cow turns to a dry Cow
Animals who cycle throughout the year over and over again are:
non-seasonally polyestrous
dairy calves
-Ensure a safe delivery
-Allow the cow to lick the calf or dry it off
- Dip navel with iodine or chlorhexidine
- calf should stand (15-20min) and nurse (30 min)
- bottle feed or tube feed
Colostrum (Liquid Gold)
initial milk containing more protein (especially antibodies/ immunoglobulins), fat, minerals, and vitamins than milk produces later
Housing of dairy calves
Calf hutches or pens
Management goal of housing
clean, dry, well- ventilated, w/o drafts
Weaning
Transition from a milk-based diet to a concentrates and forage based diet
Weaning age
4-8 weeks of age. but timing should be based on feed intake (not age)
- Holstein calf consumes 2 lbs of calf starter per day for 3 consecutive days
- jersey calf eats 1-1.5 lbs calf starter/day
weaned heifers housing
Alone or into groups in pens, in barns, or on pasture
weaned heifers feeding
goal: reach 60-65% of adult weight and height by 13-15 months of age (puberty 9-11 months)
Weaned Heifers Breeding
- AI or Bull-breed @ 13-15 months of age
- Pregnancy = 9 months
- Calve (“freshen”) @ 22-25 months of age
- join the milking herd as a Cow or 1st calf heifer
lactation curve
- Milk production increases over the first 40 - 100 days post-calving.
- Most cows produce 50% of their milk in the first 110 days.
- During lactation, cows will be bred again so that they calve on a 12-
15 month calving cycle.
Why the 12 or 13 month calving interval?
The 12 or 13-month calving interval is desirable because cows that calve every 12-13 months will give more milk than cows that have longer intervals.
The closer two lactations are together, the more time is spent during peak milk production and the less time is spent during low milk production at the end of the lactation curve.
Dry Cows
approximately 45 to 60 days prior to calving, cows are removed from the milking herd to allow for completion of calf development and for repair and regeneration of udder tissue
Present Day Dairy Farming
feed - cow - bulk tank - milk truck - testing - processing - packaging - distribution
Feed
- 50-100 lbs of feed/day
- 30-40 gall water/day
- feed amounts for 45-70% of the farm’s total operating cost
Saftey
1) temperature
2) Antibiotics? Drug residues?
3) Somatic Cell Count
4) Bacterial Count
Quality
1) % milk fat
2) % protein
3) milk urea nitrogen
Composition of whole/raw milk
87-88% water
12-13% solids (8.6% solids-non fat, 3-4% milk fat, minerals)
Water
87-88%
Solids
12-13%
Solids-Non-Fat (SNF)
8.6%
Milk Fat
3-4%
Separation in processing
milk is spun to remove debris and some bacteria and separate heavier milk fat from the lighter milk
standardization in processing
fat content adjusted
Pasteurization in processing
(high-temp, short-time, HTST) Milk is heated as it flows through the pasteurizer to 161°F for 15 sec
Homogenization in processing
Hot milk is pressurized to 2500-3000 psi by a multiple-cylinder piston pump & forced through very small passages in an adjustable valve = break down the fat particles
Rapid Cooling in processing
40 degrees F
