An “infant formula” for calves that may help them fight infection from Salmonella and other microbes, especially during stressful times, has been developed at the Agricultural Research Service (ARS), an agency release reported last week.
The dietary supplement, developed by immunologist Susan Eicher at the ARS Livestock Behavior Research Unit at West Lafayette, Ind., alters calves’ immunity enough to help them cope with transport stress, which appears to be among the worst sources of stress early in an animal’s life.
The formula contains beta-glucan from yeast cell walls and vitamin C. Studies showed it reduced stress in Holstein dairy calves taken from their mothers within 24 hours after birth and transported. To mimic commercial operations, Eicher and colleagues took Holstein dairy calves — usually 3 to 10 days old — on 6- to 8-hour trips every Monday to measure stress. They treated half of the calves in each truckload with one of two versions of the experimental formula. Formula-fed calves regained their appetites and resumed normal growth, with improved nutrient utilization, faster than those not fed the formula. They were also more active and had lower levels of fibrinogen, a liver protein that typically increases with transport stress.
The formula seems to work with the mother’s colostrum, a fluid providing nutrients as well as substances that help protect the newborn animal against disease until the young animal’s own immune system begins to function. Calves given the formula had higher levels of immunoglobulins, which are transferred in colostrum and are indicators of a good immune system.
Untreated calves experienced less stress if they were trucked before or after the fourth day following birth. According to Eicher, this may be because calves are making the metabolic transition from colostrum to milk at around Day 4.
As part of an effort to find out exactly how the anti-stress formula works, Eicher is now studying calves’ immune cells to see where beta-glucan moves and where it accumulates.
Read more about the research in the March issue of Agricultural Research magazine, available online at www.ars.usda.gov/is/AR/archive/mar05/stress0305.htm.
Editor’s Note: This article was provided by ARS.
