When considering early weaning, producers must see the vital importance of maintaining calf health. Pulling calves from the cow at half the conventional age changes the timeline of health protocols.
“You would think these younger calves would require more attention, but my experience is that the health on them is outstanding,” said ruminant nutritionist Jeff Heldt. “The number we doctor and the amount we have to monitor on a day-to-day basis is much less than your typical 600-pound (lb.) calf weaned in October.”
The field consultant with Land O’Lakes Purina Feed said the cattlemen he works with in western parts of Nebraska and South Dakota have weaned approximately 2,700 calves at a 90-day target. At first, he encouraged them to wean early to conserve forage in drought years, but Heldt said he continues to do so because it reduces cow costs, increases grass availability and shows tremendous benefit to calf health and performance.
Offhand, producers may not see the logic because they often worry about the health of their smallest calves.
“Calves at that age are not going to be as immuno-competent as older calves – that’s a function of the maturity of the immune system and it’s highly dependent on age,” said Mitch Blanding, senior veterinarian for Pfizer Animal Health beef operations. The calf will have a fully functioning immune system of its own at that age, but it will not be as efficient in responding to antigens, resulting in a slower and weaker immune response than what would be seen in older calves.
“We used to think vaccinating calves at this time was of very little value because it would be blocked by maternal antibodies. We now know that’s not entirely the case,” Blanding said. “Recent research has shown that vaccination during this early timeframe will result in a ‘priming’ of the immune system and will allow the calf to have a more robust immune response when vaccinated at a later date.”
Heldt said it comes down to timing: “The cow’s contribution to the health of these little calves is pretty crucial.” Early vaccinations can help the immune system to positively respond after the maternal antibodies have disappeared. Certain modified-live vaccines have been shown to provide a protective response at a very young age, but Blanding said that may not be enough.
“Because of immune system immaturity, one vaccination at that age may be less than optimal compared to the response you might get three months later,” he said. “So we need to keep in mind that those young calves, especially, will likely need to be revaccinated at a later date to ensure adequate protection.”
It’s also important to keep in mind the benefits of deworming these young calves, Blanding added. Calves at this age are very susceptible to the effect of parasitism, and removal of these parasites will help enhance their response to vaccines.
Weather also benefits a spring-born calf weaned in mid-summer.
“It’s going to be hot, so it might be worth the effort of having a mud hole in the pasture or shade provided in the pen when you’re weaning,” Heldt said. “But there aren’t the dramatic temperature fluctuations you would normally see in the fall, which is hugely beneficial to the calves’ health.”