How to feed dairy calves tends to vary a lot from farm to farm, maybe even from person to person on the same farm.
There have been quite a few changes in expert recommendations since Dr. Neil Anderson and others started to question whether we should severely limit how much we feed calves. There has been quite a bit of research too. Last year, a review in the Journal of Dairy Science noted that there were close to 600 research studies published on dairy calf nutrition just in the last 20 years.
One recent study looked at whether it is better to gradually increase the amount of milk fed to young calves, from birth to varying weeks of age, or to feed a larger volume right from the start. The research was done on five commercial farms that fed either whole milk or replacer. They looked at a 3-month period during the summer and a second 3-month period in the winter in case the season was important. They checked to see how well the calves grew, using both weight and height, and whether there were differences in health.
The researchers compared two different approaches to the amount that was fed. In the first, newborn calves started out being fed 4 to 5 litres a day with the amount gradually increasing so they ended up getting 6 to 8 litres a day by the time they were 7 to 14 days old. The second approach was to feed 6-8 litres a day from the very start. At 3 weeks of age, the calves fed 6 to 8 litres a day weighed 1.4 kg more and they were also slightly taller. This isn’t a real surprise because those calves would have had a chance to drink more milk or replacer during those first 3 weeks.
One of the reasons that people like to limit the amount they feed calves is because they are concerned that calves will get sick and especially that they will scour. In this research trial, there was no difference in the need to treat calves. The researchers used the dairy farmer’s treatment records but also scored calves for illness. Sickness was about the same across both feeding programs.
Another recent study looked at whether the impact of housing dairy calves individually or in pairs had an impact on their growth. The feeling was that calves housed with a buddy might grow better. Calves were housed alone or paired up when they were around 5 days old. Milk replacer was fed twice daily and calves had free access to water and starter. There were no differences in how much the calves weighed at weaning. Housing them in pairs made no difference to their growth in the week after they were weaned either. There were differences in the calves’ behaviour like how much time they spent standing. That could mean that they played more, for example, but those differences in behaviour apparently did not include eating behaviour.
Being housed with one or more buddies does seem to be important to calves though. In a study where calves were either housed alone or in groups of 4, the calves housed in groups did better at figuring out changes in their environment. The changes used in research don’t seem to relate much to actual changes that a calf might experience like a change in a waterer or a new feed, but if calves housed in groups are better at adapting to important changes in their management, it could be better for them (and the people who look after them).
Like most research, none of these three studies gives a definite answer to all the important questions about raising calves but they do serve to keep us thinking about how to improve what we do.
Dr. Robert Tremblay is a veterinarian for Boehringer-Ingelheim and lives near Guelph.
