Bovine Production Units

1. Bovine Production Units VT 270 Production Dr Dave Linn

2. Minnesota beef operations • 15,500 ranches in Minnesota (7,400 dairies) in 2003 • 2004: Mn. slaughtered 1,154,000 cattle (1,420,800,000# beef) • $1.9 billion in beef revenues in Minnesota

3. Minnesota dairy industry • $2.9 Billion total revenue • Most of the milk produced here is processed into cheese or butter • Farm #s dropping, somewhere around 7,000

4. 3 classes of bovine units • Dairy: Primary goal is to produce milk • Beef cow-calf: Primary goal is to produce calves to be fed for meat • Beef feedlot: Primary goal is to feed out calves for meat • All three tend to overlap • Dairy steer calves go to feedlot, heifers may be raised in feedlot environment • Cow-calf operation may feed weaned calves for a while, then sell to another feedlot

5. Beef Cow Calf operations • Herd size varies, but most are under 30 cows • Texas #1, Missouri #2 for beef cows • Minnesota has about 15,000 cow/calf operations, most very small

6. Cow/calf • Primary concern is reproduction and calf growth • Nutrition also geared for maximum reproduction • Tend to spend much of life on pasture, must have feed supplemented in winter in Minnesota Hereford cross cows with calves

7. Cow/calf • Tend to calve in spring after thaw • Want short “calving season” for uniform group of calves to sell after weaning in fall • Tight calving season requires intense breeding season Simmental cow with calf

8. Cow/calf production cycle • Calf born in early spring (usually) • Cow has postpartum anestrus for ~60-80 d • Hopefully gets bred at about 90d postcalving • Calf stays with cow and nurses for ~4-8 months, begins to eat some grass after few months • Weaned and sold or put into feedlot in fall

9. Cow/calf production cycle (cont) • Cow should be ~3-5 months pregnant at weaning • Cows then rest and gestate until calving in spring • Bulls VERY active in breeding, do nothing rest of year • Many operations use artificial insemination for that reason • Bull can only breed once per day for short period, AI also allows more inseminations if multiple cows are in heat

10. Cow/calf production cycle (cont)Replacement heifers • Heifer calves picked to be replacement cows stay on cow for 7 months like all calves • After weaning go to special feeding situation • Don’t grow as fast, not as fat and have stronger bone structure • Bred ~14 -16 months at 800#, calve at 24 months at 11-1200# (dept on breed)

11. Replacement heifers • Most have access to grass or hay after weaning to build structure without fat • Get supplements with high mineral levels • Should start to cycle around 11 months so they are ready to breed at 15 months Angus cross heifers Limosin heifers

12. Cow/calf production cycle • Cow gestation period ~280 days (9 months) • Should calve every year at about same time if everything works! • Uniform calves at weaning are worth more to feedlot operator

13. Weaning process • Calves that are weaned, processed (dehorned, castrated, vaccinated) and sold to feedlot at same time are under a huge stress • Most operators now do this process in steps • Process calves while on cow, often soon after birth

14. Weaning process: Preconditioning • Preconditioning: Process of getting calves ready for feedlot with least chance of problems • Involves coordination of vaccination, parasite programs, processing, weaning, nutrition, etc. • Results in significant improvement in health (↓ disease, ↑appetites, ↓death loss) • Usually ~4 week process

15. Cow/calf vet tech opportunities • Work is very seasonal for veterinarians • Spring calving season: C-sections, dystocias, neonatal problems • Fall weaning season: Weaned calf problems, cow pregnancy work, processing everything • Both reproductive herd and calves must be worked through chutes seperately

16. Cow/calf Processing Beef processing is usually high numbers of cattle going through chute restraint. Long, repetitious process.

17. Beef Feedlot Operations • Nonreplacement animals from cow/calf or dairy operations • Beef steers and nonreplacement heifers • Dairy steers • Placed into large group by size and genetics, fed to gain weight quickly • All animals will be slaughtered for beef • Can range in size from 10-25,000 head

18. Beef Feedlots

19. Beef feedlots • Dealing with incoming animals for first 30 days is most difficult task • Necropsy all dead animals, must have diagnosis! • Vaccine and processing vary with history, size, nutrition, etc. Lung tissue from beef calf that died of Mycoplasma pneumonia

20. “Shipping Fever” • Common term for pneumonia and URIs when cattle are first introduced to feedlot • Complex of stress, viruses, bacteria, etc. • Every case is different and handled differently • Early intervention essential, once lungs get chronic animals do poorly even if they live

21. Feedlot nutrition • Animals fed to gain weight quickly (>3#/day) • Fed low protein, high calorie diet (↑ grain, ↓ protein and mineral) • “Marbeling” = fat in meat, desirable for taste • American demanding lower fat hamburger, but still want high fat steaks and roasts • “Grass Fed Beef”

22. Feedlot Nutrition • By feeding TMR (Total Mixed Ration) to entire pen, can modify rations very scientifically • May change ration every 50-100# of gain • Will change every day for first 14 days in feedlot for health reasons • Cattle not designed to eat grain, must be very careful (1200# steer may get 18# grain and only 3# hay daily)

23. Beef Feedlot Diagnostic Procedures • Necropsies: Many diseases can be tentatively identified on necropsy • Huge amount of diagnostics, micro in clinic, many others sent to D-lab • Result of diagnostics should be to direct treatment and change management if necessary

24. Dairy operations • Very different from beef cow/calf or feedlot • Not trying to produce meat, dedicated to producing milk for sale • Calves removed immediately, all milk from cow is for sale

25. Dairy cow lactation curve

26. Dairy cow lactation curve • Heifers begin to milk on the day their first calf is born • First milk is colostrum, very high in IgG. 1-3 feedings given every calf for disease resistance. • Then milk is sellable, calf switched to another source of milk and heifer is milked for sale of milk.

27. Dairy cow lactation curve • Cows and heifers have similar curves, heifers are slightly “flatter” • Body condition drops as milk production increases • “Peak” = point of highest milk production, then gradual decline • Get bred 70-150 days into lactation • New technology allows later breedings, production holds higher and makes it economical • Will milk until 45-60 days before due date • Then “dry off” and rest until calving

29. Two Goals of Dairy Operations • Get maximum lifetime milk from the high investment cows • Raise supply of replacement heifers that are genetically superior to cows and healthy enough to demonstrate that superiority

30. Dairy Reproduction • With new technology, it is easier for cow to go over one year between calves and still milk well • Combination of falling body condition, high milk and hormones makes reproduction difficult at 90 days • Veterinarians use many hormones to manipulate reproduction, then these cows pass on poor genetics for reproduction to replacement heifers • Trend over time if for more difficult reproduction in dairy than beef

31. Dairy Artificial Insemination • Single bull can probably mate maximum of 100 cows per year naturally • With Artificial Insemination, one bull can be responsible for up to 50,000 breedings per year • Allows average dairy to use expensive genetically superior sires for all breedings • Also guarantees accurate breeding dates for management

32. Dairy Artificial Insemination • AI cooperative buy bulls, do testing and collect semen • Individual doses frozen in liquid nitrogen • Thawed and inseminated into cows as they show standing heat

34. Dairy Natural Service • Many dairies still breed with bulls • Saves labor of detecting heats, etc. • Depends on accurate palpation for dry off dates, etc. • Bulls can be dangerous, safety and insurance issues • Read bull aggression article carefully

35. Mastitis and Milk Quality • One of the largest issues in dairy production • We will discuss this at length later in quarter • Lots of diagnostic opportunity for techs

36. Heifer Rearing Operations • Subset of dairy operations • Many dairies do not have expertise or labor to raise replacements • Send them out to specialized operations • Dairies usually retain ownership, work with raiser to produce quality animals • Bring them back to the dairy 60 days precalving