Editor’s note: The following article was written by Phil Durst, Michigan State University extension dairy educator.
Whether individual or group calving pens are used, it is essential to reduce the incidence of cows calving in a freestall scrape alley. The exposure of these calves to manure-borne pathogens is considerably higher and the environment less hospitable. Farms that routinely monitor this group are able to keep these occurrences to less than 3 percent of calvings.
One dairy family, with a herd of around 200 cows and without the labor to monitor close-up dry cows around the clock, takes advantage of the calving cows’ natural inclination to go off by herself to calve. In their barn, the freestall area for close-up dry cows is adjacent to the straw pens for calving, with only a short gate in between. During the day, they move dry cows that appear ready to calve from the freestall area into the straw pen. At night, they simply open the gate between the two areas and cows that calve in the night naturally seek that area in which to calve. These producers report that as long as they don’t neglect to open the gate at night that no calves are born into the scrape alley.
Even cows that calve in individual stalls are often exposed to pathogens. Calving pen cleanliness is important to the uterine health of the calving dam. Generally, cows that get a uterine infection became infected in the calving pen.
In addition, the newborn calf is exposed to pathogens when it is very vulnerable due to their undeveloped immune system. Calving pens sampled in an environmental study on Michigan Johne’s Disease Control Demonstration Project farms were found to be contaminated with the pathogen that causes Johne’s disease 17 percent of the time. This was on farms where there was an awareness of disease transmission, knowledge of some of the infected animals and a commitment to reduce herd prevalence, and yet it still occurred.
Manure can be left on gates dividing pens and stay there long past the contributing cow’s residency. Cows in neighboring pens may spread manure through gate dividers and bacteria may survive on the floor or walls. Producers must work to reduce exposure, but elimination of it is not attainable. Therefore, removing calves from calving pens when they achieve standing reduces the opportunity for exposure.
Because the animals at greatest risk of infection and development of Johne’s disease are newborn calves, having a separate pen for dams identified as Johne’s test-positive can reduce the risk to the majority of calves born. That pen should be separated from others if possible and be at the end toward which pen manure is scraped so that contamination of “clean” pens is reduced.