Burgett shows producers ways to successfully raise orphan lambs
Identifying ewes who can successfully raise triplets could help U.S. producers grow sheep numbers. In fact, a triplet lamb performance study in Boise, Idaho, showed more than a 55 percent probability that a purebred triplet would make it to weaning. Another study shows that in 100 triplet litters, an additional 20 lambs could be weaned over litters of twins. The bad news is that 75 lambs out of the 100 extra lambs could be lost.
Rusty Burgett, who is the program director with the National Sheep Improvement Program, talked to producers about ways to successfully raise lambs when the ewe can’t. “Profitability is largely determined by the pounds of lamb marketed per ewe exposed. High prolificacy and high production efficiency is important,” he said. “However, extremely high levels of prolificacy may not be sustainable for ewes in extensive management.
Burgett recognizes that although producers want to increase the size of the nation’s ewe flock, the only way to accomplish it is through an increase in the number of lambs. Most producers find it harder to raise triplets, compared to twins or singles, and past studies have shown little benefit to increasing litter size above 2.2 lambs per litter.
One way to increase litter size is through efficient artificial rearing, which Burgett has identified as a way to raise lambs the ewes can’t until more efficient ewes capable of raising triplets can be produced. Burgett said the system has the potential of returning a profit for producers who develop cost-effective and labor efficient systems that can even be automated to reduce labor costs. In his example, producers made a profit of $31.48 per lamb, with costs of $64.52 and a return of $96, figuring a 60 pound lamb at $1.60 per pound. He pointed out that every situation will be different, and his figures are only an example of the potential profit a producer could make.
Which lamb to choose?
Burgett said producers should consider artificially rearing any lamb that has a low chance of survival if left on the ewe, or ones that lack colostrum. “It is not necessarily the biggest lamb or the smallest lamb. Try to cross foster the lamb first, if possible. The ewe can always do it more efficiently than we can,” he said. “If you plan to artificially rear the lamb, make that decision as soon as possible. We want the ewe to raise it, but sometimes we wait too long to make the decision that she can’t. It is much easier to get a happy, healthy lamb started on artificial rearing than a stressed, chilled, cold, sick lamb.”
COLOSTRUM IS CRITICAL
The most important part of artificial rearing is getting colostrum into the lamb. “It will ensure success,” Burgett said, but timing is critical because lambs are not born with an active immune system. The lamb should receive 10 percent of its body weight within the first 24 hours. Burgett recommends four feedings at four hour intervals.
The colostrum should be warm enough to feed lambs, but Burgett cautions producers against microwaving it because it damages the proteins and immunoglobins. He suggests using a water bath, placing the container of colostrum in it, and warming the colostrum to 107 degrees F. “By the time you feed it to the lamb, the temperature will be just right,” he said.
The lamb can be fed with a bottle or a tube feeder. “If you have a lot of lambs, I like using a tube feeder because of the timing factor, plus I know the exact volume each lamb is getting,” he said.
Colostrum can be collected from the ewe, but Burgett recommends collecting it soon after birth so it still has as many immunoglobins present as possible. Immediately after birth, the colostrum will be more concentrated and contain more antibodies, he said. The lamb’s ability to absorb those antibodies across the gut wall decreases with time, so the majority of the colostrum should be in the lamb within the first 12 hours.
If the ewe doesn’t have enough colostrum, Burgett said producers can get some from another ewe in the flock. Ewe colostrum is ideal, and it can be frozen and thawed. Other sources are cows or goats. “They have a lower nutrient value and lower immunoglobin level than ewe colostrum, but it still contains immunoglobins for passive buildup in lambs. Producers should be cautious about disease transfer, especially from cattle. “Cattle colostrum can spread Johnes disease, especially if it is from a local dairy. Make sure cattle colostrum is from a Johnes-free dairy farm or is pasteurized colostrum,” he said.
Producers can also purchase powdered colostrum replacers and supplements, but there is a difference between the two, he said. Colostrum supplement is designed to be added to existing colostrum a producer has on hand, and a colostrum replacer can be used in place of colostrum.
Burgett said after the last colostrum feeding, he likes to place lambs in a lamb stand made from 6- to 8-inch PVC pipe, and ear tag, dock and castrate them. They are then transferred to a training pen with 10-12 other lambs, to get accustomed to milk replacer. “The lambs usually lay around a lot after banding, so we use that to our advantage because it makes them hungry,” he said.
Burgett said producers should look for a lamb milk replacer that mimics sheep milk. It should contain at least 25-30% fat, 20% lactose, 24% protein and less than 0.5% fiber. If it is medicated, it can prevent diseases like coccidia. Burgett said acidified milk replacer options are also available that can prevent spoilage if it isn’t consumed right away. The lower pH increases intake, improves digestion, and has caused less scours in other animal species, he said.
On average, a lamb will consume about 18 pounds of milk replacer from birth to weaning, which is about 30 days of age. About 10 pounds of the milk will be consumed in the last 10 days before weaning, Burgett said. “If you feed milk replacer beyond 30 days, you are just wasting your money,” he said. “Lambs can be weaned earlier than 30 days, but make sure they weigh at least 30 pounds when they are weaned.”
Burgett told producers to wean lambs abruptly, not by watering down milk replacer. “It increases the risk of bloat, because they will try to consume more to make up for it,” he said.
Lambs can be fed milk replacer in bottles, a lamb bar or with an automatic feeder. “On a small scale, you could feed milk replacer through a bottle, but it is very labor intensive if you have very many lambs to feed, and it can lead to times where they will gorge themselves. There are simple solutions that exist that mimic natural feeding,” he said. ❖
— Clark is a freelance livestock journalist from western Nebraska. She can be reached by email at firstname.lastname@example.org.