50% of calf mortality in the first year, occurs within the first 6 weeks, so every effort must be made to ensure that calves are given the best chance possible for survival.
As the busy calving season approaches preparation is key for the cow, calf and farmer to survive this hectic period. The importance of a strong, robust immune system for the cow cannot be underestimated, hence the importance of a good quality pre-calving mineral. The quality and quantity of the pre-calving minerals will influence both the health of the cow and the calf, so make sure to choose wisely. Evidence shows that good calf rearing practices are crucial to ensure long- term productivity, such as improved health, optimal age at 1st calving and greater milk production with greater mammary development.
1. CALVING FACILITIES:
Clean, well-disinfected calving pens are necessary as the newborn calf is very susceptible to infectious agents such as Cryptosporidium, Rotavirus, E-coli and Salmonella.
Calving pen supplies should include a calving jack, calving gown, ropes, gloves, chlorhexidine navel spray, calf revival gels and tags. Each new-born calf should be tagged, have its navel sprayed and the calf and cow numbers recorded on their farm system.
1st milk, within 2 hours of birth, 3 litres.
Why is the colostrum vital for survival;
• Higher content of energy, protein, vitamins, and minerals
• Lower sugar content is less likely to cause scours
• High level of antibodies for passive transfer of immunity.
Colostrum quality declines at a rate of 4% /hour and the ability of the calf to absorb the immunoglobulins decreases with each hour that passes.
Test the quality of the colostrum using a refractometer.
3. RUMEN DEVELOPMENT:
The development of rumen in calves can directly nutrient digestibility, feed intake and eventual growth. Water, straw and coarse starter feed must be supplied to stimulate rumen development.
• Water provides lubrication, is essential for microbial growth and fills rumen volume.
• Straw scratches the rumen for increased size to encourages rumen development and rumination.
• Coarse starter crunch promotes the growth of muscle layers & ruminal papillae.
A calf requires 3-6L water/kg of dry feed, depending on the ambient temperature.
Excluding water from a calf’s diet:
• reduces dry feed intake by 60%,
• reduces growth by over 25%
• increases the cost of rearing by 35%.
Calf starter ration should be palatable, coarse and highly digestible.
The coarseness benefits the growth of the muscle layers in the rumen wall and helps develop the rumen papillae to optimize absorption capacity.
High volumes of milk/ milk replacer and high-fat content in the milk reduce pre-weaning starter intake, leading to a slower rate of rumen development.
A young calf spends 19 hours/day lying down so it needs a clean dry bed with adequate ventilation for fresh air. If bedding is damp: the moisture uses the heat from the calf’s body to evaporate into the atmosphere.
A good calf house can save a fortune in terms of time, calf weight gain, lower mortality and vet bills. Ensure calves are fed at the lowest point and can lie at
the highest and warmest part of the housing. A minimum fall of 1:20 is required so for a 4-metre pen.
Combination of wind and stack effect:
The stack effect means that the air that is heated up by the livestock in the building rises, escapes through the outlet area (apex) and is replaced by fresh air through the inlet area.
The provision of adequate air space and ventilation in calf housing will dramatically decrease the risk of calf pneumonia and other diseases.
Cases of pneumonia in calves can have lifelong implications:
It can reduce 1st lactation yield by 4%
It can reduce 2nd lactation by 8%.
It can reduce the number of overall days in milk by ~109 days
It can reduce beef stock live weight by 6%
Scour accounts for 30% of all deaths in calves < 1 month old:
1. Isolate sick calf
3. Ensure calf is warm: Young calves need additional energy to keep warm if the environmental temperature is <15°C.
(Rule of thumb: at 0°C calves need about 50 % more energy just for maintenance and keeping warm)
4. Focus on hygiene to prevent further spread of infection