Weaning calves successfully!
Feeding and managing preweaned calves is expensive on a per day basis. Fortunately, it’s a relatively short time in the life of the calf and a minor percentage of total rearing expenses. Traditionally, the goal for preweaned calf management has been to encourage rumen development and early weaning to reduce these expenses on a cost/day basis. Shouldn’t the goal be to manage the calf to achieve her genetic potential for growth, lactation potential and health? There is no time in the life of the animal when growth will be more efficient! This period also has a large impact on health and future performance.
Consider beef cattle where calves consume multiple meals each day and aren’t weaned until 6 months of age or more. The early life dry diet for the beef calf is usually pasture with high sugar and digestible fiber content. Compare this to how we manage the dairy calf with twice a day milk feeding, individual housing and calf starter grain. Over the past few years, the trend to feed more milk has become more common and has made successful weaning of dairy calves much more challenging, especially if we try to wean them at a young age!
How can we manage calves to attempt to replicate the situation with the beef calf, but within the practical limitations of the modern dairy farm?
· Individually housed calves are typically fed twice daily by bucket or bottle. Calves have been weaned by feeding once daily which constitutes a significant stress to the calf, particularly when daily milk intake may exceed 6 L/day. To ease the transition, reduce feeding by 1 L/feeding for at least 4 days and then go to 1X feeding. Extending the weaning process to 2 weeks is likely to be even less stressful (one week of reduced milk/ feeding and one week of 1x/day feeding
· The autofeeder is well suited to more “normal” weaning. Ad libitum milk intake is recommended (limited to 2L every 2 hours) for 28 to 40 days. Reduce milk intake over 4 days from 12L to 8 or less L of milk/day. Hold milk intake to 8L for 10 days and then reduce milk over 14 days to 2L. This provides sufficient nutrients from milk for better early growth and the stepwise reduction in milk encourages a starter intake and an easier transition to life without milk.
· When to wean? Most published research involved weaning at less than 6 weeks of age. It should not be surprising then that these calves experience decreased body weight gains due to the lower digestibility of nutrients from calf starter grains as compared to milk. Research comparing calves weaned at more than 12 weeks compared to early weaned calves shows that metabolically prepared for life without the nutrients provided by milk. In comparison, prolonging milk feeding by 2 to 4 weeks encourages superior growth, improved intestinal development and higher feed efficiency as compared to calves weaned at less than 7 weeks of age. Is the additional expense in feeding milk for a longer period offset by improved health during the post weaning period or ultimately more milk during the first and later lactation? Unfortunately, there are few studies comparing the economic implications of 6 week weaning to 8- to 10-week (or more) weaning. It is logical to assume that the ability to better manage intake through autofeeder systems simplifies weaning in a less stressful manner.
· The first consideration for the calf starter is that it tastes good to the calf! Always make sure to have fresh starter and discard any that has become moist from rain or calf water. When milk allocations exceed 8L/day research indicates better performance post weaning with crude protein levels of ~22%
· Starch levels range between 20 and 40%. Higher starch levels appear to increase the likelihood of acidosis in the calf which is not desirable. To replicate the beef calf’s diet, sugar content of up to 14% is suggested. Lower starch and higher sugar content diets appear more favorable to rumen development. More rapidly digested starch sources from wheat or barley grains should be avoided in calf starter grains.
· Forage. The availability of forage to the preweaned calf has been debatable. The low energy content relative to feed grains suggests limiting it in the diet. Research has shown that providing limited amounts of chopped small grain or grass hay promotes starter intake. It is not uncommon to observe calves consuming straw bedding during the preweaning period. Alfalfa hay or silages are not recommended during the weaning period.
Water Clean water should always be available. During the winter offer water immediately after feeding milk. Clean buckets to prevent algae growth during the summer.
Housing. The calf hutch or other individual housing systems have been the “gold” standard for calves. However, research and experiences of many dairies shows that calves housed in pairs or in group housing consume starter earlier, adapt to post weaning systems better and exhibit other behavioral benefits extending throughout their lives. They adjust to new situations (cow grouping) or new feeds better. An added benefit is that calf rearing on dairies is better perceived by the consumer.
How can the dairy facilitate successful weaning from both the perspective of the dairy owner and the calf!
· Provide a high quality, liquid diet based upon either milk or milk replacer. Feed sufficient solids from this diet to support gains, which enable the calf to double its birth weight by 56 days. This means more than 6L of milk or a high quality milk replacer (~24% CP) per day.
· Wean calves by a step-down reduction in milk rather than abrupt transition to once daily feeding.
· Calf starter palatability is the primary concern. It should contain ~ 22% protein with moderate starch levels – 20 – 25% and sugar content of 10 to 15%.
· Offer high quality chopped grass or small grain hays or straw prior to and just after weaning.
· Plan for housing calves in pairs or group housing systems prior to weaning.
· Manage your calves, which means having sufficient information to evaluate the economic consequences of changes to your calf feeding program.