The recent rains in 2015 and 2016 have resulted in a flush of early weeds and grasses producing seed heads that can be one of the contributors to pink eye (Moraxella bovis). Pink eye is a bacterial infection that causes inflammation of the eye. It can cause temporary blindness or in some cases permanent loss of vision. Pink eye is contagious and can spread rapidly. Face flies are also a huge contributor in the spread of the infection. The flies will land on the drainage from the eyes and transfer it to other animals. The secretions from an infected animal are another means of spreading the infection to other cattle. It can begin with a simple seed head getting lodged in the eye and progress to a full-blown infection.
Early detection is the key to prevent the rapid spread of infection in your herd. Learn to watch for early signs and symptoms:
- Heavy watery eye discharge (tear trails).
- Excessive blinking due to sunlight sensitivity.
- Cloudy cornea.
- Redness of eye and surrounding tissue.
- Mild to moderate elevation of body temperature.
- Decreased appetite.
When you recognize any of these symptoms, you should inspect all animals that have come in contact with the affected animal in order to determine the course of treatment needed. If possible, you should try to isolate any animals presenting symptoms. One recommended course of treatment is to administer the antibiotic Oxytetracycline by intramuscular injection according to product label. This is a more expensive approach than most eye ointments but has been proven to be more effective with faster results. If the infection has progressed to the point that the eye becomes cloudy and blood vessels are growing across the cornea, you will need to apply an eye patch. In most cases, the patch is applied to preserve the vision in the affected eye. In severe cases, a veterinarian can suture the eye closed.
Implementing a few best management practices can be one of the most effective ways to prevent pink eye.
- Fly control is one of the most important practices you can implement. There are many different ways to reduce the number of flies including ear tags, fly spray, dust bags or treated back rubs. Rotating cattle through different pastures to reduce the buildup of manure piles can also help with fly numbers.
- Mow pastures or use grazing practices to reduce the amount of seed heads and thistle that can become lodged in the eye.
- Isolate any new cattle purchased (incubation period is usually two to three days; in some studies, it has extended to three weeks).
- Consider vaccines for prevention, on the advice of your local veterinarian.
Pink eye can reduce feed intake, weaning weights and milk production, all of which can lead to financial losses. Infection rates can change from 1 or 2 percent up to 80 percent of the herd at the peak infection rate. Each producer will need to determine the course of action to take based on the economic impact to his or her individual operation.