When buying cows, ensure that you don’t buy in Strep ag as an unwanted extra. This bacteria can cause high Bulk Milk Cell Counts and clinical cases in dairy herds. Once introduced to a herd, infection spreads quickly from cow to cow at milking and can quickly develop into a significant mastitis and milk quality problem.

Strep ag is usually brought into a farm in the udders of infected cows. With Strep ag causing problems in high cell count herds across Australia, and many farmers buying in cattle to increase herd size, the risk is real. And once introduced, the highly contagious Strep ag can spread rapidly through a herd. The best approach by far is not to introduce the bacteria in the first place.

Some ways of avoiding Strep ag when buying cows are listed below:

• Buy heifers rather than cows where possible.

• Only buy cows from herds that have consistently low Bulk Milk Cell Counts.

• Don’t buy a cow with an Individual Cow Cell Counts above 250,000 cells/mL.

• Check the udders, teats and foremilk of cows before buying them.

• Milk the introduced cows last until you are confident that they are free of mastitis.

To be extra certain of the status of any introduced cows, consider taking a milk sample for culture from all purchased cows, even if no abnormalities are apparent when you check the udder. This could prove to be a very good investment if it helps you identify infected cows before they join the milking herd. Consult your veterinarian for more advice.

Remember, not all brought in cows are bought in. So even as a favour, NEVER milk other people’s cows with your herd.

More detail about the checks you should make when buying cows are given in the Countdown Downunder Farm Guidelines for Mastitis Control.

Image and caption
Does that new cow have Strep ag?

Countdown Downunder Farm Guideline or Technote
Farm Guideline 21

Keywords
Strep ag, cow associated, buying cows, prevention

Word length
310