Expert Advice: How to Wean Calves with Minimal Stress

In this article, GAIN Ruminant technical specialist Elaine Brady discusses weaning calves and the gradual transition from milk to grass and concentrates.

Weaning Calves and Reducing Stress

• Calves can be successfully weaned both abruptly and gradually if the rumen is adequately developed and consistently consuming at least 1.5kg per day.
• Weaning the calf gradually reduces the risk of stresses on the calf’s digestive system and the risk of illness such as pneumonia and subsequent growth stunt.
• Reduce the milk volume being fed over 7-10 days. If calves are being fed milk twice a day, weaning can be achieved by cutting down to once a day feeding.
• If calves were fed larger volumes of milk (>6L per day) a greater level of concentrates need to be fed to maintain similar energy intake levels.
• To minimize digestive adjustment after weaning, weaned calves should feed same concentrates fed prior to weaning.
• Stressful events such as disbudding or mixing of age groups should not take place in the weeks before or after weaning to prevent a growth stunt.
• Concentrates can be limit-fed in two daily feeds from two weeks post weaning, but not earlier.

With plenty grass available and the anticipation of improved weather conditions calves will be turned out in the coming weeks. Calf turnout to grass can be a stressful period, new forage, new surroundings, changing weather conditions, bigger calf group to socialise in and a reduction in concentrate feeding levels.

After weaning, calves are not yet fully functional ruminants with a capacity utilize forage weather that be silage or grass sufficiently to achieve growth requirements. The weaned calf has a smaller rumen in comparison to older animals. Therefore, small changes to the diet have a more significant impact on the calf. Interruptions to performance during the lifetime of the heifer may offset target weights being achieved.

When calves do get introduced to grass the intake of fiber is reduced, resulting in animals not chewing the cud as much as they should, increasing the risk of digestive upsets and reducing calf performance. Calves require fiber in the diet to cope with the transition to grazing. The sudden introduction leafy grass may cause a number of dairy calves display wasting symptoms post weaning and after turnout due to effects associated with this stressful transition period.

Tips for Feeding

GAIN RumenCare Calf Nut is a complementary feed uniquely pelleted for calves  transitioning to grass. The ingredients are not ground giving the product a ‘coarse in a nut’ appearance and effect, designed to take good ‘care’ of calves during and after the critical turnout stage. The high level of digestible fiber from beet pulp and soya hulls will provide the calf with much needed fiber when grazing to encourage rumination and help calf performance during turnout and afterwards. It also contains a unique calf nutrition and health pack called RumiDrive comprised of four key elements.

• Buffer Feed: Acid Equaliser is a high capacity buffer included to help neutralise and improve the rumen environment. Rumen microbes need a stable rumen pH of 6.2-6.5, but lush grass with little fibre creates a much more acidic environment. The microbes become much less effective therefore, nourishing the calf less effectively and seriously affecting performance.
• B Vitamins: are included to help reduce the risk of B Vitamin deficiency, including Vitamin B1, Vitamin B2, Vitamin B6 and Vitamin B12. B vitamins are necessary for many metabolic functions related to health and growth. Calves have a significant metabolic demand for these vitamins due to their lean growth and as part of change in metabolism to the ruminant state which increases during stressful periods such as weaning and adaption to grazing.
• Proviflore C: is a natural essential oil animal health product included to help reduce the risk and manage a coccidiosis challenge that it may encounter during its first grazing season.
• Yeast: Diamond V is a natural yeast included to help enhance full gut development.

GAIN Rumencare Calf Nut can be introduced before calf turnout, so that the calf is familiar with the concentrate, when the calf is actually grazing outdoors. Feed at 1kg to 1.5kg per 100kg bodyweight per day, depending on forage quantity and prevailing weather conditions.

First Publishd 2 May 2024