Another common affliction of animals this time of the year is mastitis. This is an infection of the mammary glands.
The way to really understand this problem is to break it down. I look at mastitis as environmental and contagious. Environmental mastitis is caused by environmental bacteria getting into the udder of the animal, be it sheep, goat, mare or cow. Generally these bacteria are of the strep, E. coli, or manure bugs. An easy milker will lay down in whatever or get contamination on the teat and here we go. On cows we normally have a 3 mm opening at the lower sphincter. If we have damage to the end of the teat and get a 4 mm opening, this will allow bacteria to go straight into the udder and cause the infection.
Now, the most deadly one of this is E. coli. This is also known as Acute, Toxic or Cow Killer Mastitis. The E. coli releases an endotoxin and causes the cow to die of endotoxin shock. We have to block the toxin and get rid of the bacteria, while supporting the cow.
Contagious mastitis and having most or your entire herd infected will put you out of the business. Contagious mastitis is mainly caused by Staph and/or 1 or 2 Strep’s. The scourge of the dairy industry if Staph. aureous. This Staph is everywhere and when allowed to go unchecked it can and will travel from one cow to the next until your whole herd is infected.
Staph will generally infect your cow during late lactation and just sit there until she is dried off. During the dry off period is when it becomes very active, ruining udders. During lactation you will notice a higher somatic cell count and/or higher bacteria count from the milk company. But, hardly any evidence of it in the milk, as apposed to E. coli, will give you a sick cow and water for milk. These Staph infected cows act like normal well cows. The only way to identify them is to test, either by California Mastitis Test, Somatic Cell Counts or bacteria counts.
Once identified, we need to isolate and treat. By isolation I mean to milk them last to prevent the infection from going from them to every other cow in your milk string. Treatment curing lactation is very unrewarding. I normally only run about 25 percent chance of clearing these Staph infected cows with antibiotics. I have had better luck with vaccines.
Most of my success treating Staph comes from culture and sensitivity testing and dry treating Staph with an extended treatment protocol. I will recommend these cows be dried off early and generally treated for five to seven days in a row with the appropriate antibiotic.
For prevention, we need to remember to be hospital clean. Staph can be cultured right off your hand or arms.
Dr. Tim E. O’Neill, DVM, owns Country Veterinary Service in Farmington, Ark.
