Nutrition, environment impact dairy calf growth

LUBBOCK, Texas — Nutrition as well as a clean, comfortable environment impact the average daily gain of dairy calves.

“Nutrition and environment are both important and we need to do them both well,” said Michael Ballou, professor and chair of the Department of Veterinary Services at Texas Tech University. “But often you can get more improvements with a better environment than with nutrition.”

For feeding milk solids, data shows for every 1 liter of increase above 4 liters per day, dairymen should expect to see 12, 25, or 45 gram per day improvement in average daily gain of calves, said Ballou during a webinar hosted by the Dairy Cattle Reproduction Council.

“That equates to 1.5-, 3.1- or 5.6-pound improvement in weaning weights,” he said. “If you’re feeding 4 versus 6 quarts of milk, you should expect an improvement in weaning weights from 3 to 8 pounds.”

Most dairymen understand the importance of colostrum management.

“Feeding no colostrum versus feeding excellent colostrum equated to about 44 grams per day improvement in average daily gain of the calves,” Ballou said. “A six-hour delay in giving colostrum resulted in a reduction in average daily gain of 24 grams per day.”

When researchers evaluated calves at a temperature-humidity index, or THI, of less than 50 and increased it to 69, that resulted in a decrease of average daily gain by about 50 grams per day, the university professor said.

“Looking at temperatures of 50 to 70 degrees, there was an increase in average daily gain as the calves went from a cooler temperature to a more thermal neutral temperature,” he said.

A study evaluated bedding in hutches including sand, straw, shavings or no bedding.

“No bedding or sand resulted in a dramatic decrease in average daily gain in the winter months versus straw or shavings,” Ballou said.

Calf nutrition including starter intake has long-term impacts on the milk production of cows.

“When comparing high starter intake to low, this study shows a 1,140-pound difference in lifetime milk production,” Ballou said.

“For every pound increase in weaning dry matter intake, there is about 500 pounds more milk production over the life of the animal,” the university professor said.

“There is quite a bit of evidence that animals that gain more during the first six months of life are less likely to be removed from the herd,” he said.

“Calves with a low average daily gain were 3.4 times more likely to be removed from the herd and they were 2.4 times more likely if they had medium average daily gain.”

Early life body structure is important for dairy animals.

“It has a large impact on lactational performance and survival in the herd,” Ballou said. “Starter intake at weaning is associated with lactation performance, as well as average daily gain.”

It’s not just the pre-weaned period, Ballou said.

“Birth to puberty matters so you should maximize average daily gain not only in the hutch, but also maximize the transition off milk, onto the starter and into the grower ration,” he said.

A study at Michigan State included three treatments, feeding milk replacer, transition milk or a formulated transition milk that included milk replacer and colostrum replacer. These three treatments were fed to calves at days two through four.

“The calves fed the transition milk or the formulated transition milk had a reduction in eye scores for goopy eyes and a reduction in inflammation,” Ballou said. “These two groups of calves also had about a 7-pound improvement in weaning weights.”

In a study, calves were fed high levels of starch that was coming from ground corn and oats or whole corn, oats and cottonseed hulls.

“The starch was reduced from 43% starch with the ground diet to 35% starch for the second diet,” Ballou said.

“The calves on ground diet consumed about 3.1 pounds of dry matter versus 4.6 pounds of dry matter for the other diet,” he said. “There was a dramatic improvement in weaning weights for the calves fed the second diet.”

The researchers harvested the animals to look at rumen lesions.

“The calves that ate the ground diet had higher rumen lesions than the second diet,” Ballou said. “To mediate that, feed whole grains, less starch and more digestible fiber to limit rumen acidosis.”

A study aimed to improve rumen pH, calves were fed a control diet, a diet with live yeast or a diet with live yeast with a probiotic.

“The live yeast can utilize lactic acid as an energy source so when we fed the live yeast, we saw an improvement in rumen pH,” Ballou said.

“Fermentable carbohydrates are going to stimulate rumen development, but we need to do it in a smart way,” he said. “If we get rumen acidosis, the starter intake will be depressed and average daily gain is going to be suppressed, as well.”