A Vaccine for Mastitis in Goats

Mastitis in goats can be devastating not only to a dairy herd but to backyard goat owners, too. It drops milk production and impacts the health of the nursing kids at the very least. At the most, it can cause a doe to lose her udder or her life. Mastitis in goats is most common in the first week after kidding and again in the third week of lactation. These are periods when milk production increases rapidly, often causing an overly full udder. Engorgement puts a doe at risk of mastitis for multiple reasons, namely that the stagnant milk serves as a good bacterial breeding ground when not flowing regularly. Fortunately, there is a vaccine against one of the main bacterial causes of mastitis newly available in the United States.

This vaccine is under the name VIMCO for Vaccine Inactivated Mastitis in Caprines and Ovines. While it has been widely used in Europe since 2014, it is only just now USDA-approved for goat use in the United States. Fortunately, it can be used in both meat and dairy goats. However, even though the name implies it is also being manufactured for sheep (ovines), it has not gained USDA approval for use in sheep in the United States. That would be considered off-label use.

There are many causes of mastitis in goats, but some of the most prevalent are bacteria from the Staphylococcus family. VIMCO is made from inactivated Staphylococcus aureus. An inactivated bacterial vaccine means that the bacteria have been completely killed. Dead bacteria cannot make your goat sick or cause mastitis, but they can stimulate your goat’s immune system to make antibodies against that same bacterium. When the immune system makes antibodies, it identifies a piece of the “invader” and makes antibodies or a specific protein from white blood cells that will bind to the “invader” and destroy it. When the goat later faces an infection from Staphylococcus aureus, their body will already recognize the bacteria as bad and have the blueprint to quickly make the specific antibodies to fight it. With this greatly improved ability to fight the bacteria, the goat’s infection will likely be mild or even nonexistent.

Another major component of the mastitis vaccine is the addition of biofilm from the Staphylococcus aureus bacteria. Biofilm is a thick slime produced by bacteria to help hide and protect it from the goat’s immune system and from antibiotics. It happens to be very common in Staphylococcus bacteria and is one of the main ways in which the goat becomes ill. Having biofilm in the vaccine allows the goat to produce antibodies for the biofilm as well as the bacteria itself. They accomplished this by choosing a strain of Staphylococcus aureus that tends to produce a high amount of biofilm.

This mastitis vaccine is to be administered five weeks before the expected date of kidding then again three weeks after the first dose. Each dose is 2mL injected deep into the muscles of the neck. This two-vaccine procedure should be repeated with every pregnancy because there is not yet enough data to determine how long immunity lasts. Do not give this vaccination within 60 days of a planned slaughter. This is a refrigerated vaccine that must be brought up to room temperature before administering. Because of this, all doses from the bottle should be used or discarded within 12 hours. Use a new bottle for the second dose. At $ .50 per dose and available in bottles as small as five doses, it will hopefully not be a temptation to put the warm, opened bottle back in the refrigerator for later use.

Since 2014, producers in Europe have given this mastitis vaccine to over five million small ruminants. The results included a 58% reduction in clinical signs of mastitis. This impacts milk production most of all, but also general animal health. A goat who gets mastitis is likely to get mastitis again and is often culled in dairy operations. This will save the lives of animals and save producers the cost of animal replacement and loss of milk. For backyard goat owners, it saves stress, heartache, and the health of nursing kids. Even with a vaccine, a good mastitis prevention program is a must. Preventing mastitis is much easier than treating it.

With mastitis, there are clinical and subclinical cases. Clinical cases are when the goat has visible signs of mastitis often characterized by a swollen, very tender udder. Subclinical mastitis can occur without visible signs, except for the kids failing to thrive. The milk production and quality can be lowered enough that at eight weeks there is often an eight-to-11-pound weight difference in the nursing kids of does with subclinical mastitis versus healthy does. A dairy herd could have 30% of does with subclinical mastitis without realizing it. When milk is sold, mastitis whether clinical or subclinical will raise somatic cell counts. Somatic cell counts above a certain limit mean that the milk is unable to be sold. Somatic cells are body cells from any organ, but in milk are mainly white blood cells.

Mastitis in goats can be detrimental to large dairy operations, meat goat operations, and backyard goat owners. It affects the health of the nursing kids and the ability to sell the milk. Mastitis can even kill a doe if not treated quickly. Stephanie Sexton, Products Manager at Premier1 Supplies says that they are “excited to be able to offer this [mastitis vaccine] to the goat people.” With modern technology, we can have healthier herds and fewer tragic endings to goats with mastitis.

Originally published in the November/December 2021 issue of Goat Journal and regularly vetted for accuracy.