D A I R Y I n i t i a t i v e s N E W S L E T T E R
V o l u m e 1 2 I s s u e 1 S p r i n g 2 0 0 3

Good Nutrition Helps Fight Mastitis

by JIM LINN
University of Minnesota

Some dairy producers say they've seen an increase in mastitis when they've switched feeds or fed more of certain feeds, particularly protein supplements. Research has not shown that common, high-quality feeds cause mastitis when fed in a balanced diet. However, we do know that certain nutrients are needed to build a strong immune system to fight off mastitis. Providing a diet that is balanced in nutrient content and contains high-quality feeds is the best way to help cows fight mastitis-causing organisms.

Iowa State veterinarian Jesse Goff recently reported a relationship between metabolic diseases at calving and the incidence of mastitis. Cows with milk fever are eight times more likely to develop mastitis than cows without milk fever. Ketosis increases the likelihood of mastitis twofold. A retained placenta probably does not cause mastitis, but is most likely symptomatic of a depressed immune system. His conclusion was that disruptions in nutrient balances leading to metabolic diseases are also very likely to be a major factor in the susceptibility of cows to mastitis organisms.

What can you do to ensure that your cows have the diet they need to support a strong immune system? First and foremost is to make sure they get enough energy. Goff estimates cows need 40 percent more energy than normal when they're fighting infection. For a 1,300-pound cow, this equals nearly 5 pounds of extra corn. To help cows fight infection, get plenty of energy into them right after calving and when they are sick.

Other nutrients that are particularly important for a healthy immune system are protein, vitamin A, vitamin E, selenium, copper, and zinc. Be sure to meet the requirements for these nutrients in all dairy cattle rations every day. The average lactating dairy cow should take in about 150,000 IU of vitamin A and 500 to 1000 IU of vitamin E per day. She should also get 10 to 20 parts per million (ppm) copper in the diet (about 350 milligrams per day), 0.3 ppm selenium in the diet (7 milligrams per day) and 40 to 80 ppm zinc in the diet (about 1,400 milligrams per day). Protein needs vary with level of milk production, but typical lactating cow diets should be 16 to 18 percent crude protein.

D A I R Y I n i t i a t i v e s N E W S L E T T E R
Volume 12 Issue 1 Spring 2003