Seasonal weather can pose challenges to udder health, often resulting in producers indicating an increase in herd SCC (somatic cell count) and mastitis cases. A combination of several factors causes SCC to rise, writes Chris Mondak, Iowa State University Extension dairy field specialist. It’s important to review good management practices that can control the factors that lead to increasing SCC and mastitis.
- Reduce the stress load on the cow.
Cows under stress may develop a weakened immune system which can result in increasing SCC and mastitis. We can provide no magic bullet solutions here — just good management practices. Each of the important factors in this checklist warrants an article of its own. Use this resource as a reference to help you review key elements of your operation:
A sound nutrition program exists
- Balanced ration that provides adequate protein, energy and effective fiber?
- Good transition cow ration and management?
- Overcrowding avoided at the bunk, especially for dry cows and fresh cows?
- No molds in the feed?
- Herd monitored for signs of sub-clinical rumen acidosis? (low-level, but chronic, rumen acidosis is a stress that causes poor immune function. This can manifest as increased bacterial infections; i.e., mastitis with poor response to treatment.)
- Clean, dry stalls provided?
- Overcrowding avoided?
- Adequate ventilation?
Challenge from contagious mastitis organisms absent or controlled
- Bulk tank monitored periodically for presence of staph aureus, strep ag, and mycoplasma?
- Strep ag cows treated, staph aureus segregated or culled, and mycoplasma culled?
2. Bolster natural immunity.
Research done at The Ohio State University showed that cows fed supplemental vitamin E in their rations had lower SCC and fewer cases of clinical mastitis. Cows fed 4000 IU did the best, but the level of 1000 IU in animals one month before and one month after calving seems to be most cost-effective. Discuss this with your nutritionist and veterinarian.
The core antigen vaccines such as Enviracor J-5 offer cost-effective measures of bolstering the cow’s ability to battle the challenge of environmental mastitis pathogens. Since animals in early lactation have high risk for environmental mastitis, these vaccines are usually given in the dry period and boostered in early lactation. Discuss the various core antigen vaccine options with your veterinarian to identify the vaccine most suitable to your herd.
3. Reduce the stress to the teat end.
Keeping teats soft and healthy is important year-round but particularly important in winter. Dr. Leo Timms, animal science professor emeritus at Iowa State University conducted research to identify the causes of the teat-end cracks, callouses, and scars seen in winter. These lesions can lead to higher SCC and mastitis because the damaged teat ends become more difficult to clean properly at milking time and result in increased entry of mastitis bacteria during milking.
Measures to prevent and control teat-end lesions include:
- Use proven teat dips that contain 5% to 10% skin conditioner and effective germicide.
- Ensure vacuum levels neither too high or too low.
- Use proper milking techniques that involve proper teat cleaning and stimulation, followed by unit attachment in 1 to 1.5 minutes after udder prep.
- Use milking procedures similar to controlling contagious mastitis (i.e., clean hands, individual towels.)
- Blot teat ends dry after 1 minute of post-dip application in extremely cold weather.
- Avoid overmilking because prolonged machine on-time increases teat-end stress.
- Providing windbreaks and feeding indoors for cows not kept in confinement barns.