Mycoplasmas are unusual bacteria that can infect all ages of cattle, and can cause arthritis, pneumonia, and death. Infected dairy cows may also contract mastitis, metritis, or virtually cease milk production. The most common mycoplasma affecting cattle is M. bovis; there are several other Mycoplasma spp. as well. Because standard microbial culture methods do not isolate Mycoplasma spp., special laboratory methods are needed for diagnosis. Mycoplasma spreads by inhalation and respiratory secretions and also at milking time via contaminated inflations in milking units. Mycoplasma spp. have also been detected in straw, sand, recycled manure, and other bedding, often associated with cows with mycoplasma mastitis lying on that bedding. Therefore, producers often ask about mycoplasma-positive recycled bedding’s risk to baby calves. We have found mycoplasma in straw, recycled manure, and some other environments, including hospital pens where cows sometimes calve. However, we have found it much more likely to be found in sand than other bedding types, all on farms with cows already mycoplasma-positive. Therefore, we investigated whether mycoplasma-positive sand bedding infected mycoplasma-free dairy calves
