CA10 - Dairy Cattle 3

CA10 - Dairy Cattle 3

1. 9. Target weights for Holstein Friesian heifers (24mo calving)

   • Turn out (1st summer) 200kg
   • Service starts (60%mature BW) 400kg!!!!!!!!!!! (LEARN THIS)
   • Calving 550-600kg
   • ***DAILY WEIGHT GAIN = 700g/day***
     • Regular weighing essential! to check
     • Daily weight gain (grams/d) is numerically equal to mature BW (kg)
   • Excessive growth rate before puberty = XS fat in mammary gland -> lower milk production
   • Overfeeding around parturition -> XS fat in pelvis -> dystocia
   • Underfeeding around parturition -> Poor milk yield

2. 10. Health problems asso. w/ inappropriate nutrition for heifers

   • Not enough long fibre/lots of conc -> poor ruminal development -> ruminal acidosis & bloat
   • Poor quality forage -> Pot-bellied -> Fail to grow at correct rate

3. 11. Service of Heifers

   • Choice of Bull
     • Easy calving index (produces calves w/ short gestation length). Holstein Friesian or beef (A. Angus/ Hereford) bulls can be used.
   • Management of heifers
     • Serve in Dec for autumn calving.
     • Before service: 400kg BODYWEIGHT & housed 4-6 wks before
     • Supplementary feeding for 6 wks before & 6 wks after service
       • Improves fertilisation & implantation & conception
     • No stressful events (e.g. sudden changes in feeding)
     • Can have vaccines before service to prevent abortion (e.g. BVD)
   • Service Management
     • 1) Natural service (easier to manage as no need for heat detection. 1 bull to 25 heifers. usually A. Angus & Hereford)
     • 2) AI (Needs heat detection/ oestrous synchronisation)

4. 12. Preventative Veterinary Treatments

   • Housing - Pneumonia vaccine, Louse treatment
   • 1st season @ grass - Oral lungworm vaccine, Anthelmintic (e.g. drench)
   • 2nd season @ grass - Fly control for summer mastitis

5. 13. Preparation for entering dairy herd

   • Housing
     • Acclimatise heifers to housing (esp. cubicles) - otherwise prolonged standing (-> lameness), Lie in dunging passageways (->mastitis)
   • Feeding
     • Feed part of post-calving early lactation diet for 1-2 wks before calving (Allows ruminal flora to adjust) - prevents ruminal upsets & acidosis
   • Routine
     • Walk heifers through parlour daily before calving to acclimatise