Teat sealants applied to uninfected cows at dry-off have been very effective in preventing new cases of mastitis during the dry period
The routine use of antibiotic therapy for dry cows has been questioned because of concerns about over-use of antibiotics. Some researchers and advisors recommend treating only infected cows with dry cow antibiotics. In fact, the World Health Organization recommends reduction of antibiotic therapies for animals and humans to prevent emergence of antibiotic-resistant human pathogens. However, there is good evidence that uninfected cows can become infected with mastitis-causing organisms during the dry period when they are not treated.
Teat sealants may provide a solution to this problem. Teat sealants applied to uninfected cows at dry-off have been very effective in preventing new cases of mastitis during the dry period. In New Zealand, teat sealants (without additional treatment) are currently recommended for cows with somatic cell counts of less than 150,000 cells/ml at dry-off. Non-antibiotic anti-microbial agents would enhance teat sealants and possibly increase their utility in whole herd applications.
Bacteriocins are anti-microbial proteins produced by some bacteria. The natural foodgrade bacteriocins, nisin and lacticin 3147, are effective inhibitors of Gram-positive bacteria. Lacticin 3147 has been shown to be effective against Gram-positive mastitis organisms. In work reported at the 2001 British Mastitis Conference, a teat sealant containing lacticin 3147 was tested (Meaney, et al., The use of a bismuth-based teat seal and the bacteriocin lacticin 3147 to prevent dry period mastitis in dairy cows). The teat sealant with lacticin 3147 was effective in controlling Strep. dysgalactiae in the dry period following an experimental challenge. In lactating cows challenged with Staph aureus, teat sealant plus lacticin 3147 reduced both the number of infected quarters and the population of viable bacteria in the infected quarters.
Meaney, et al., concluded the following:
- Adding a non-antibiotic anti-microbial like lacticin 3147 to teat sealants could provide additional protection against Gram-positive mastitis bacteria during the dry period.
- A main advantage is that this approach avoids introducing antibiotics.
W.J. Meaney*, D.P. Twomey†‡, J. Flynn*, C. Hill‡ and R.P. Ross†
*Dairy Production Department, Teagasc Research Centre, Moorepark, Fermoy, Co. Cork, Ireland
†Dairy Products Centre, Teagasc Research Centre, Moorepark, Fermoy, Co. Cork, Ireland
‡Microbiology Department, University College Cork, Cork, Ireland
** This paper was presented at the 2001 British Mastitis Council. It has been summarized by Milkproduction.com staff.
British Mastitis Conference