Weaning lambs to dry feed can be a stressful transition for young lambs. Supplying adequate levels of lamb-specific milk replacer and mapping a weaning strategy prior to the switch can help to ensure that the changeover goes smoothly for young lambs while ewes transition to the parlor.
Begin planning for weaning well in advance of when milk replacer is removed from the lamb’s diet by granting grain access to young sheep. Dairy sheep producers can add forages and grains by three weeks of age when the natural conversion to solid feeds begins.(1) At that time, the developing rumen can start to break down small amounts of grains, so starter feed mix should be offered.
Starter feeds are typically protein-based palatable grain mixtures that are offered free choice to young livestock while they are still on milk. If the lambs remain with the ewes for part of the day, the starter feed should be fed in a specific feeder with openings too small for adult sheep but large enough to fit growing lambs. Lambs that are separated from adult ewes to be fed milk replacer can receive the grain in feeders or troughs.
Dave Thomas, Ph.D., of the Department of Animal Sciences at the University of Wisconsin, says that, since the young lambs are not fully functioning ruminants, the dry diets need to be low in fiber, high in energy and protein and processed into a pellet or meal.
Mike Neary, extension sheep specialist at Purdue University, says that a starter feed should contain at least 14 percent crude protein (with 18-25 percent crude protein levels being ideal) that includes high energy content, balanced minerals and elevated palatability.(2) A viable starter feed option listed by Purdue University includes: 80 percent grain sorghum, 10 percent oats and 10 percent oilseed meal with alfalfa hay available at all times.
Still, it is important to remember that rations should be formulated based on individual needs of a lamb crop and available feedstuffs. For instance, Thomas recommends a 22 percent crude protein diet that is high in corn grains and also includes: soybean meal, liquid molasses, feed grade limestone, ammonium chloride and a salt vitamin mineral mix formulated for sheep.(3)
Whatever ration is selected, dairy sheep producers are encouraged to monitor Vitamin E levels in the diet to promote efficient growth. Further, urea should not be used as a protein source in pre- and early post-weaning diets of young lambs as the ingredient cannot be broken down in the developing rumen. Urea can typically be added to the ration when the lamb reaches 65 pounds.(4) By monitoring consumed starter feed levels, producers can determine a weaning timeline. The transition should occur based upon individual lamb growth and consumption rates rather than group age. Neary adds that lambs are typically able to break down solid feeds in their rumens once they consume starter feed levels that equal 1 percent of their body weights. For example, if a lamb weighs 20 pounds, he or she should consume at least 0.2 pounds of starter feed before being weaned.
Along with starter feed, lambs should have access to free choice water.
“Prior to weaning, the majority of liquid in a lamb’s diet comes from lamb-specific milk replacers,” says Dr. Tom Earleywine, director of nutritional services for Land O’Lakes Animal Milk Products. “Supplying clean, fresh water to the lambs in addition to Ultra Fresh® Lamb Milk Replacer will help young lambs become accustomed to water before the milk replacer is removed from the diet and can help prevent dehydration during this transition period.”
Earleywine adds that ration and pen changes should be avoided two weeks prior and two weeks after weaning as consistency and cleanliness can prevent added stress. For the same reason, potentially taxing procedures, including vaccination, castration, worming and tagging, should be completed at least two weeks prior to the weaning day.
Through both periods, it’s encouraged to keep groups of lambs together. Lamb groups should not be broken as hierarchy and group bonds have already been formed.
By keeping stress levels low and supplying starter feeds and adequate levels of lamb-specific milk replacer, artificially-reared lambs can be weaned from milk replacer as early as 30 days of age. At this point, lambs should have consumed approximately 20 pounds of milk replacer powder and weigh at least 25 pounds.
“It all comes back to management,” Earleywine adds. “The combination of high-protein grains and a quality milk replacer early in life can help alleviate the stresses of weaning and help this year’s lamb crop begin the next step into joining your milking flock.”
For more information on Ultra Fresh® Lamb Milk Replacer, visit www.lolmilkreplacer.com.
 Schoenian, Susan. “Weaning Lambs.” Sheep 201: A Beginner’s Guide to Raising Sheep. 23 February 2011. http://www.sheep101.info/201/about.html.
2 Neary, Mike. “Management of Ewes and Lambs at Weaning." Purdue University. 23 February 2011. http://ag.ansc.purdue.edu/sheep/articles/manewes.html.
3 Thomas, David L. “Husbandry of Dairy Animals: Sheep: Replacement Animals.” University of Wisconsin-Madison
4 Umberger, Steven. “Feeding Sheep.” Virginia Cooperative Extension. 1 May 2009. http://pubs.ext.vt.edu/410/410-853/410-853.html