AHPS week 5 - 6 Flashcards
(51 cards)
What does Animal Health Australia do?
Facilitates partnerships between government and livestock industry
Provide national approach to animal health systems
What are three examples of fertilisers?
Super phosphate
Potassium (POTASH)
Urea (nitrogen source)
What are some benefits of maximising reproductive performance?
Fewer cows sold empty or late
More rapid genetic gain
Less resources directed at correcting poor performance
Better production in each lactation for seasonal herds, or per cow/year in year round herds
More calves to sell or raise
What are some pros of year round calving
Less pressure to adhere to tight timeline
Reduced repro performance is not as pronounced
Can supply milk all year round
What are some cons of year round calving
Doesnt match the pasture growth curve well
Additional labour required
Reduced number of calves over a cows lifetime and less genetic gain as a result (because longer inter-calving intervals)
Intercalving intervals can be prolonged meaning less time in peak lactation
What are the three major factors that contribute to pre weaning health in calves
Colostrum
Environment
Nutrition
How much milk replacer do you feed dairy calves? How often?
10 - 12% of bodyweight, twice daily for the first week then once daily thereafter
If you feed too much can get scours - max 5L for Hols/Fres and 4l for Jers
What do you feed dairy calves to stimulate rumen development? How much?
Grain- high in propionate and butyrate which strongly stimulate rumen development. This should be fed in small amounts from the first week of life.
Why would you not choose hay as a concentrate for young calves?
Metabolised to acetate which is a less potent stimulus for rumen development
Describe 4 things you might do in calf rearing
Small groups
groups of similar ages
Provide ventilation
Separate scouring calves
Describe how to wean calves using concentrate feed
Increase the daily supply of concentrate by 0.75-1.5 kg per day once the calves are approaching 2 months. Slowly wean them - this ensures rumen will develop in readiness for weaning
What are the usual weaning weights for HF and J calves?
HF - 70-80kg
J - 50-60kg
What are the usual weaning ages for HF and J calves?
Early: 6 - 8 weeks
Late: 12
What is the target joining weight for Jersey heifers?
300 - 320 kg
What is the target joining weight for HF heifers?
380 - 400 kg
Roughly how many lactations do we expect out of a dairy cow?
6 or so
How can early heifer calving improve heifer welfare?
They enter the dairy for the first time ahead of the main herd - get used to it in less-stressful environment
Have a longer gap between calving and joining again - more time to recover
What are some signs of heat in cows?
Sniffing others Allowing to be mounted Mounting others Mucoid discharge from vagina Behavioural changes such as pacing Frequent squirts of urine Swollen vulva Turning head to flank
How long does oestrus last in a cow?
Anywhere between 1-28 hours, though average is 15h.
When does ovulation occur relative to oestrus?
12h after oestrus has finished.
What are two examples of heat detection aids?
Tail paint
Pedometer
What technologies are available to synchronise cow heat?
Prostaglandins > remove the CL and induce heat in 2 - 2.5 days if given between day 6 and 15 of cycle
Progestagens - provide endogenous progesterone source inside cow, removal induces oestrus
What is the 21 day submission rate?
The proportion of the herd detected in oestrus and submitted to service in the first 3 weeks of mating.
What affects the 21 day submission rate?
Whether the cows are cycling - nutrition?
Whether the heat is detected - training, observation, weather
Whether the detected cows are mated - most likely if AI program
