Weaning is undoubtedly one of the most stressful times of a calf's life. Here are three areas to consider when improving the transition to solid feed.
1. Plan milk feeding to optimise concentrate intakes
Rumen papillae line the rumen and absorb Volatile Fatty Acids (a source of energy). During weaning the calf must swap the source of energy from lactose and fat to volatile fatty acids.
Calves are not born with functional ruminal papillae, and so they must be developed during the pre-weaning phase for functionality post-weaning.
Papillae develop in response to concentrate consumption, this process takes 21 days from the start of solid feed intake. Eating concentrate is a learned response, so should be offered from birth even though calves will not eat significant amounts until 3 weeks old.
Papillae development takes 21 days from the start of concentrate consumption
Reach peak milk intakes in the first 2-3 weeks of life and follow with a longer weaning period. This can ensure calf energy requirements are met throughout as well as encouraging starter intakes. Calves should be consuming 1-1.2kg/day of concentrate before weaning.
Discuss milk feeding plans with your vet, or see our Youngstock Nutrition | Dairy Calf Vet course for more information on developing a feeding plan.
2. Prevent acidosis
Whilst concentrate intakes are essential in ruminal development, a balance must be made in order to prevent acidosis from high levels of volatile fatty acid production. A low rumen pH can result in damage to the papillae and destruction of favourable microflora.
Prevent acidosis by ensuring palatable fibre is available, provide constant access to fresh water and ensure feed space is adequate for the size and number of calves.
3. Choose quality starter pellets
Palatability is the priority when choosing starter pellets. Calves do not like dusty concentrates and course mixes are generally the most palatable. Finely ground particles are will cause a higher risk of acidosis as the starch is released more quickly. Ensure fresh starter is provided daily and remove any residues frequently.
Look for starter pellets with higher levels of starch compared to fibre, maize and oats are both highly palatable sources of starch. Soya and distillers offer quality protein sources which are also palatable for calves. High fibre ingredients such as palm kernels should be avoided as main components.
Optimise concentrate intakes by offering starter pellets with high palatability
Design a feeding plan to meet energy requirements and allow calves to consume sufficient concentrates
Avoid acidosis around weaning by offering fresh forage and water
Look out for signs of ruminal development, such as cudding, before weaning to check calves are ready for the transition
Sherwin, V., & Remnant, J. (2018). Weaning and postweaning management of dairy replacement heifers. In Practice, 40(10), 449-456.