Q.
How can I reduce weaning stress?
A.
Weaning is the most stressful time in the life of a lamb/kid. In addition to the stress of being separated from their dams, there is nutritional stress. Even though lambs/kids may not be getting much milk anymore from their dams, the nutrition that the milk provides is still beneficial, especially if the lambs/kids are pasture-reared. Lambs/kids are more susceptible to diseases, especially coccidiosis, at the time of weaning. It is important that weaning be carried out in a manner than minimizes stress.
Ewes/does should always be removed for weaning. Lambs/kids should be left in familiar surroundings. This way, lambs/kids know where everything is, especially their feed and water. Lambs/kids should continue consuming the same diets as before they were weaned. Vaccinations and other treatments should be done prior to weaning. Lambs/kids should not be handled at the time of weaning, other than to separate them from their dams. Separation should be gentle, ideally using some sort of handling system.
It is important that lambs/kids be vaccinated for overeating disease type D (clostrdium perfringins) twice before weaning. Lambs/kids should be eating creep feed before weaning. The level of concentrate consumption prior to weaning has a big effect on weaning stress. It is very important that weaned offspring have plenty of fresh, clean water available. If lambs/kids are not being creep fed and will be grown out on pasture, it is recommended that they be weaned later (e.g., 120 days).
There are different opinions as to what constitutes low stress weaning. Traditionally, it was recommended that weaned lambs and ewes be kept out of earshot, as it was believed that calling between them would increase stress. Research with cattle suggests than fenceline weaning may be less stressful. With fenceline weaning, offspring can see, hear, and even make contact with their dams.
Several years ago, researchers at Lincoln University (Missouri) conducted a series of experiements to evaluate different weaning strategies. Lamb performance was not improved with fenceline or evening weaning. In fact, lambs that were fenceline weaned vocalized more, meaning more stress. These results differ with cattle. Instead, they concur with the traditional recommendations for weaning lambs. Similar research has not been done with goats. Are they like cattle or sheep?
Anti-suckling devices have been advocated for low stress weaning. The offspring are allowed to stay with their mothers, but are prevented from nursing via a nose ring or flap that clamps onto their septum. This allows their dams' udders to dry up without the stress of separation. It is questionable whether these devices are low stress and good for animal welfare. I don't know anyone using them.
Weaning later (90 days or later) is lower stress than earlier weaning (90 days or less). There isn't any stress when lambs/kids are naturally weaned by their dams. Of course, there here are pros and cons to different weaning ages. The appropriate age of weaning depends on the production system.
05/10/2021
Additional reading
Performance and behavior of spring-born Katahdin lambs weaned using traditional or fenceline-weaning methods in the morning or evening
Sheep weaning best practice - Western Australia