Somatic cell count can be an indicator of animal performance and milk quality. As somatic cell count increases, milk yield and quality will decrease. In fact, many milk processors will not receive milk from a farm unless its somatic cell count is below a certain threshold.
A high somatic cell count is usually an indicator of an infection that has triggered an inflammatory response in the mammary gland. One common cause of high somatic cell count is mastitis in dairy cows. Mastitis can be caused by environmental pathogens or can be passed from cow to cow.
When a cow is dealing with any inflammatory response, including a response caused by mastitis, they will utilize nutrients and energy — close to 2 kg of glucose per day — to fuel that response, leaving fewer nutrients available for milk production. This results in a lower milk yield by that cow. The immune cells that rush to the mammary gland to fight the infection will show up in the milk. This can lower milk quality by changing the flavor and the color.
Management is the best defense against mastitis-causing pathogens, but at the same time, pathogens are always present in barns. Supplementing your dairy cow nutrition program with performance trace minerals, like zinc from ZINPRO®, can reduce the incidence and severity of mastitis in dairy cows, reduce somatic cell counts and help your cows produce high-quality milk.
Mastitis and Somatic Cell Counts: How Are They Related?
With mastitis in dairy cows and high somatic cell counts, it is a chicken and egg situation. Both can occur independently, but one can also cause the other.
If a cow becomes infected with mastitis, the inflammation can damage to the epithelial tissue, resulting in white blood cells invading the mammary gland and causing a high somatic cell count. If a cow is dealing with inflammation due to some other stressor – heat, for example – the inflammation can open the door for mastitis to occur as well.
An Outside-In Approach to Controlling Mastitis in Dairy Cows with Performance Trace Minerals
Mastitis in dairy cows and the resulting increase in somatic cell count can be caused by environmental pathogens — like E. coli — or contagious pathogens — like staph aureus — that are passed from cow to cow. Contagious mastitis can be passed from cow to cow if a milker is using the same towel to clean off multiple cows’ udders, is not wearing gloves or is not properly cleaning the equipment.
Whether those pathogens are picked up from the environment or are passed from cow to cow, the mode of entry is the same: through the teat end.
There are two layers of protection to stop pathogens from damaging the mammary gland and causing mastitis in dairy cows: the teat keratin just inside the opening of the mammary gland and the epithelial tissue on the inside.
The teat keratin is the plug on the outside of the udder that prevents pathogens from entering the mammary gland. It has bactericidal properties that can kill bacteria on contact as they try to invade the gland.
The epithelial tissue on the inside of the mammary gland is much like other tissues in the body. Epithelial cells are “bound” or “stitched” together by complex protein structures called tight junctions. Epithelial tissue must be constantly repaired and replaced, and the integrity of tight junctions maintained in order to protect against pathogens such as mastitis.
If pathogens are able to get past the keratin plug, then it is up to the inner epithelial tissue to be strong enough to hold off the infection until the immune cells arrive and kill the infection.
Zinc Helps Prevent Mastitis in Dairy Cows, Lower Somatic Cell Counts
Zinc is involved in over 300 enzyme functions and is critical to improving immune function. It plays a key role in keratin formation, including teat keratin — the mammary gland’s first line of defense from the outside. It is also critical for the integrity of the epithelial tissue on the inside, so that if the pathogens do get through the keratin, the epithelial barrier can minimize the damage. Supplementing your dairy nutrition program with zinc from Zinpro® Performance Minerals® can improve the production of keratin within the teat end to help keep pathogens out of the mammary gland and can produce an extra milligram of teat keratin over the course of a day.
Supplementing your dairy cow nutrition program with Availa® 4 at the start of the dry period can reduce somatic cell counts by 30,000, which is equal to regaining about 1% of a cow’s milk yield. When you feed performance trace minerals as a part of your dairy nutrition program, pathogens have a much harder time penetrating the teat keratin and entering the mammary gland. That said, there’s nothing that will stop every pathogen. Epithelial tissues and the tight junctions that hold them together are the animals first defense when dealing with pathogens. Thus, nutritional solutions that strengthen the epithelial barrier on the inside can help keep the pathogens out until the immune cells take care of them, even if they get past the teat keratin.
To learn more about feeding performance trace minerals in your dairy nutrition program, contact your Zinpro representative today.