Expert Insight into Calving in Autumn 2021

As many dairy farms come into their busiest time of the year, the relentless but valuable focus on calving and calf rearing routines needs to be maintained to ensure the productivity and success of the next generation of milkers. However, the reality of their not being enough hours in the day or enough people to muck in is all too common.

When it comes to calf health and vigour and wasting less time and money on tending to poorly calves, colostrum really is “liquid gold”. It’s the most important thing to spend time on getting right, and it’s the most important thing to get the timing right on!

The type of placenta in which a calf is grown (namely a syndesmochorialplacenta), means that calves are born with little to no immunity. For sufficient passive transfer of immunity from mother to calf, calves must receive colostrum to the amount of 10 percent bodyweight ideally within the first 2 hours of life. Furthermore, with colostrum quality as important as colostrum quantity, calves must also receive 200g IgG in their first feed. A reading of 22 percent on a brix refractometer equates to 50g IgG/L, so feeding 4L of this colostrum will provide the required 200g IgG.

Colostrum consumption also programmes the young calf for life, and many studies support the idea of improved growth rates, greater development, and more milk production from calves fed higher volumes. Feeding a high quality, digestible milk replacer after colostrum will help to support these growth rates, of at least 0.85kg/d, which are required to reach the recommended age of first calving of 22-24 months.

Age of first calving is of huge importance to farmers, and an increase in milk production from heifers is of economic gain. Increases in fertility and longevity are also correlated with elevated planes of nutrition, so investments must be made in the pre-weaning period to produce strong, profitable heifers.

Julia Wadeson, Calf & Youngstock Specialist
1^st September 2021