Researchers in Norway had questions: Do personality traits, especially sociability, influence feeding behaviors of dairy calves? And, how do personality traits in combination with different weaning methods affect weight gains? The answers to their questions could help producers choose the best weaning methods for their dairy stock.
In a natural setting, cows and nursing calves together set the feeding schedule for the calf, and calves wean gradually, completing weaning at varying ages. In contrast, in many traditional rearing systems there is minimal cow-calf contact, the weaning schedule may be strictly determined, and reductions of milk intake and increases in concentrate feed are based solely on the calf’s age. Research on calf personality and feeding behaviors has indicated their might be some kind of interaction between personality and feeding behaviors. These studies focused on single-purpose dairy breeds, mainly Holsteins, so the researchers also hoped to expand our knowledge base by looking at animals bred for both dairy and meat, in this case the dual-purpose Norwegian Red.
Personality Testing for Calves
Novel environment and novel object tests were selected to characterize calves’ responses to new situations and determine if the calf was an exploratory or fearful personality. Calves were placed in an arena that was empty and unfamiliar for the novel environment test, and then could voluntarily interact with a bucket they had never seen in the novel object test. The calf was scored on its willingness to explore the arena and approach the black tub. The animal’s sociability was measured by putting animals in the unfamiliar arena together. To see how important the group was to the individual calf, they separated it from the group and scored it based on how often it called to the rest of the herd. (You can read more about the testing here.)
After analyzing calf behavior, they isolated three factors interpreted as personality traits: playful/exploratory, vocal/active (interpreted as a type of sociability trait where vocalizations and pacing serve to communicate with other calves when isolated from the herd), and interactive in a group. These factors together, explained more than half of the variance in calf outcomes. The researchers found that calves that were more exploratory consumed more milk per day preweaning and more concentrate per day over the experimental period. Calves that were more vocal and active had lower preweaning milk intakes and lower concentrate intakes over the experimental period. Calves that were more interactive in the group test had lower preweaning and weaning concentrate intakes. These associations did not vary with weaning method. However, the team found that calves weaned based on concentrate intake had higher average daily gains postweaning, likely due to consuming more concentrate per day over the entire experiment, than calves that were weaned by age.
The team concluded that the sociability traits of Norwegian Red calves were related to individual differences in milk and concentrate intake. “Although the relationship between personality and feeding behavior and growth did not depend on weaning method,” observes lead investigator Laura Whalin, “gradual weaning based on individual concentrate intake provides an opportunity for calves to wean at a pace that fits the needs of each individual calf, contributing to better calf health and overall welfare.”
What Can We Do With This?
You’re probably not going to personality test your calves, lambs and kids, so you might think, “This is dumb!” But that would be missing the point of what the researchers discovered: Animals have different personalities, and those personalities affect feed intake and weaning weights. To adjust to those personalities, without having to test for them, all you have to do is provide an environment where the different animals can meet their individual needs. In this case, it was as simple as providing concentrate so that the individual could increase the amount it ate to meet its needs. It’s a win for the calf and a win for the producer!
What other ways might you use this idea of personality and feed intake? I’d love to hear your out-of-the-box thinking in the comments below!