Gene therapy and the prevention of mastitis in dairy cattle

Abstract Text:

Mastitis in dairy cattle is an inflammation of the mammary gland and surrounding udder tissue, often an immune response to a pathogen invading the teat canal. It can also be a result of chemical, mechanical, or thermal injury to the udder. Mastitis can present clinically or subclinically, so routine testing and examinations are done to prevent the spread of infection. This infection is most often treated with antibiotics, but during antibiotic treatment, the cow’s milk is not able to consumed or sold, because it contains antibiotic residues. It is an on-going epidemic in the dairy industry, and monetary losses are accrued from the milk that must be disposed of due to antibiotic usage, reduction in milk yields due to permanent damage to the udder as a result of infection, labor costs to tend to infected cows, veterinary and medicinal costs, and in extreme cases, premature culling costs. Studies are being conducted to show that gene therapy may be a possible solution to prevent mastitis. Research has been done in an attempt to transfect the udders of dairy cattle with cercropin B, a lytic peptide found in Cercropia moths, that has broad spectrum bactericidal properties. This technology has been applied to other species through different experimental procedures and has yielded favorable outcomes and a decrease in targeted infectious diseases.  The research with dairy cattle has not yet yielded favorable results, but with some experimental modifications, could be proven effective in preventing mastitis. This practice, once perfected, could be incorporated in routine dairy farm procedures, such as vaccine administration, and could reduce or eliminate antibiotic treatment of mastitis and reduce the losses of milk unable to be sold because of residual antibiotic contamination.

Keywords: gene therapy, mastitis, dairy cattle