By Kirsten Nickles and Anthony J. Parker
Weaning is the start of an independent life for the beef calf. Though weaning can be a stressful time for the calf, beef cattle producers can minimize the stress at weaning by using science based weaning methods. A negative weaning experience can be a catalyst for disease and death in feeder calves, however, a positive weaning experience can help minimize disease and stress through the marketing system.
The most common weaning strategy in the U.S. beef industry is the abrupt removal of calves from their dams at approximately 180-220 days of age (Rasby, 2007). Abrupt weaning is not a good weaning method because it places a great deal of stress on the calf. The immediate cessation of milk in the diet of a calf and the complete maternal separation associated with abrupt weaning are often exacerbated by other stressors that have negative effects on the calf. An unfamiliar environment, a new diet, transportation, co-mingling with unfamiliar calves, and pain from husbandry practices such as castration while also being denied social contact and care by the cow will stress a calf. When calves undergo prolonged periods of stress they are predisposed to disease and a failure to thrive in later stages of the marketing chain. There is scientific evidence to indicate that multiple stressors at weaning is physically and psychologically stressful for calves and should be avoided.
There are several alternative weaning methods to choose from apart from abrupt weaning, including: fence-line, two-stage, and the use of a trainer cow. Fence-line weaning keeps the calf from nursing, but still allows for social contact between cows and calves through a fence-line. Calves are typically separated from the cows by a fence-line for anywhere from 3-7 days until the calf and cow adopt independent activities. To perform fence-line weaning, a good fence that will keep cows and calves separated is necessary. Calves will likely try to find a way back to their mothers and may attempt to go through the fence; the right fencing material is therefore important. Barbed wire is not ideal for this weaning method. High tensile wire, wood, or woven wire are better fencing materials for the fence-line weaning method and will help to keep cows and calves separate without putting calves at risk of injury and misadventure.
Exploratory behavior is common in cattle, and calves will commonly pace the fence-line at weaning. Weaning calves into a familiar pasture is one way to help reduce their pacing and walking behaviors. Pasture size is another consideration when fence-line weaning to help reduce walking behaviors. While there has not been any research performed to evaluate an ideal pasture size, reducing the length of the fence line is preferable at weaning because this will decrease the area available for fence-line walking. Another option is to perform fence-line weaning in a dry lot. If calves are fence-line weaned in a dry lot, however, there can be some negative consequences. One negative consequence is that calves will walk the perimeter of the lot. A dry lot may cause dusty conditions that can further predispose a calf to bovine respiratory disease (Beef Cattle Research Council, 2019). Additionally, if calves are weaned in a dry lot, they must adjust to both a feed bunk and a new type of feedstuff. If calves are weaned on pasture, supplements can still be provided to ensure that they are meeting their nutritional requirements, but they are already accustomed to grazing forage. Weaning on pasture reduces the number of novel experiences that the calf will have to adjust to while being weaned from their mother, however, pastures rich in energy and protein and total digestible nutrients should be grazed to maximize nutrient intake during this stressful time.
Two-stage weaning utilizes anti-suckling nose-flaps that are placed in the nostrils of a calf and prevent nursing, while still allowing social contact with the cow. The nose flaps are usually left in the calf for 7-14 days and are then removed when the calf is completely separated from the cow. Two-stage weaning is a viable option, however, to insert the nose flaps you will need to process calves through the chute and then a second time when you are ready to remove the nose flaps. While it is not common, it is a possibility that some calves may lose their nose flaps. Nose flaps are approximately $2.25/unit, and these can be disinfected and used again the following year. One important consideration similar to fence-line weaning is calf nutrition. If you are leaving calves on pasture, but they cannot nurse, they need to be on forage rich in digestibility and nutrients or be provided supplements to ensure that they are receiving the recommended amounts of nutrients.
The use of a trainer cow at weaning is a method in which calves are abruptly weaned, but a mature, non-lactating cow is placed with the calves to help encourage calves to find the feed bunk and water faster, and to help decrease separation distress. Cattle are gregarious animals, therefore a further source of stress for calves at weaning is the disruption of their normal social hierarchy. In a cow-calf hierarchy, the brood cows are the dominant figures in which calves follow and model their behaviors. It has been proposed that using mature animals as “trainer animals” or “social facilitators” will have positive effects on performance, health, and behavior of feedlot calves (Loerch and Fluharty, 2000). The use of a trainer cow is a non-invasive, non-labor intensive management strategy that is a viable option for producers to implement. This method can easily be done in both pasture and feedlot settings, depending on availability of resources. This is also an ideal weaning method if a cull cow is used as the “trainer cow”, as it is an easy way to supplement the cull cow and add body condition before marketing this cow. There are, however, considerations that should be made prior to using a trainer cow as an alternative weaning method. If a cull cow or non-pregnant cow is used as the “trainer cow”, producers must control the cow’s estrus cycle in order to prevent her from displaying estrus as this can increase walking behaviors in calves, especially bull and steer calves. If weaning calves in a feedlot, or if supplementing calves and the trainer cow on pasture, producers must provide enough bunk space such that calves are not intimated by the trainer cow at the bunk in the early stages of weaning. If insufficient bunk space is provided, the mature trainer cow may intimidate calves from coming up to the bunk and could negatively impact eating behaviors.
While weaning is inevitably stressful for calves, these alternative methods have been shown to minimize the amount of stress placed on calves during weaning. By using low stress handling techniques and decreasing the number of stressors simultaneously place on calves at weaning, you will be setting your calves up for success in the next phase of production.
Source : osu.edu