Dairy Bull Health

Posted by Administrator on January 14 2006 08:14

Biosecurity

Major diseases that can enter your farm with a bull:

• BVD
• Salmonella
• Mycoplasma
• Hairy Heel Warts
• Trichomonas
• Johnes

Protect yourself

• If you have a disease eradication plan or vaccination program in place make sure new bulls meet criteria

Have a checklist of questions to ask when purchasing a bull

• Vaccination status
• History of disease on the farm
• genetic merit

Isolate bulls on arrival

Vaccinate and deworm on arrival and booster 2-3 weeks before exposing them to the cows

Breeding Soundness Exam

1. Ask for a copy of the exam results
2. Examination looks at:
   1. Sound feet and legs
   2. General health
   3. Scrotal circumference
   4. Rectal exam of internal repro organs
   5. Semen sample is examined for motility and morphology

• A passing score indicates that there are no physical reasons that a bull will not be sound for breeding
• There is no measure for libido

Lameness

• A lame bull is not a useful bull
• Rear claws may wear quickly when in confinement
• May get bruising, ulcers, abscesses
• Laminitis is common as they are on high energy lactating cow ration
• Rest bulls in dry, dirt lots to give a break from the wet, rough concrete
• Monitor any swelling above the hoof as this may be footrot, an infected ulcer, or heel wart

Infertility

• Rotate bulls for rest and to increase libido
• While bulls are resting allow access to lactating cow ration along with free choice hay
  • Sudden ration changes can lead to acidosis
• Heat Stress
  • Sperm are very sensitive to high temperatures
  • Short term high temps can lead to temporary infertility
  • 60 days to generate new sperm
  • Heat stress effects can linger for several months
  • Fat bulls are less tolerant to heat stress (and have lower libido when it is hot)

Health Problems

• Good vision is important
  • Monitor for eye injuries, pinkeye
  • Treat early
• Acidosis
  • From eating lactating cow ration
• Injury
  • Provide non-slippery flooring for mating

Safety

• Make sure all workers and anyone who enters pens (nutritionist, vet, repairmen) know where the bull is
• Remove aggressive bulls at the first sign
• Build escape routes (gate pass-throughs and ground clearance)
• Have well-built gates and handling facilities for moving bulls