For the last 6 years, the Michigan State University Dairy Cattle Teaching and Research Center (MSU Dairy Herd) has actively engaged in a Johne’s disease (JD) control program. The ultimate goal is to eliminate the disease from the herd. Johne’s disease is a chronic disease caused by the bacteria Mycobacterium avium subspecies paratuberculosis (MAP). The disease is transmitted from adult to young animals primarily through feces, colostrum and milk. Control of the disease requires long-term diligence in maintaining management changes designed to slow down the risk of disease transmission.
Recently, a team from Michigan State University completed a multi-year research study looking at control and prevention of JD in cattle herds. One of the key findings from this study was the need to stop the transmission of the disease in the maternity pen. Anything that can be done to reduce calf exposure to MAP in the maternity pen is highly beneficial to preventing the spread of the disease.
Key to Controlling MAP
An environmental study of farms enrolled in the Michigan Johne’s Disease Control Project showed that 17 percent of cultures taken from maternity floors were positive for MAP. In addition, another study in which swab cultures from the skin of cows in maternity or close-up dry cow pens showed that MAP could be cultured from 6 of the 7 animals tested, even though only one of those cows was test-positive (fecal and blood) for MAP. Therefore, the risk of exposure in the maternity pen is high; the longer time spent by the newborn calf in that pen increases the risk of JD infection. A key management strategy for controlling MAP transmission in dairy operations is to remove the calf from its dam as soon as possible after birth.
To facilitate rapid removal of calves from their dam at birth, the Dairy Cattle Teaching and Research Center staff designed and built neonatal calf warming boxes to provide a means to care for newborns and reduce the opportunity for pathogen exposure. Essentially, these “calf incubators” allow for rapid removal of calves from their dams immediately after birth, even when they are still wet. This protected environment allows for the calf to dry rapidly while protecting it from pathogens that often are transmitted in the maternity pen. The boxes are located immediately next to the maternity pens to facilitate the rapid movement of calves into them.