Pinkeye season is upon us and for many stocker operators it means routine treatment of affected calves. It’s important, though to also address preventative measures that will stop the spread of this highly contagious disease. Vaccination programs are certainly an option for prevention, but if you haven’t already vaccinated your calves, you’re too late. But don’t be disheartened, as there are other practical means for preventing the spread of pinkeye in your calves.
Fly control is a critical component to pinkeye prevention, however that topic deserves its own article to cover the various methods and options available to a producer. In addition to fly control, there are other things you can do to affectively address pinkeye. No one method addresses all of the problems, so it’s important to put together a “total game plan.”
Clip your pastures. If the grass is too long or headed out in your pastures, clipping it will go a long ways to preventing eye irritation in your calves, which if not addressed, can initiate the beginning of a pinkeye breakout. The irritation of dust, plant pollen, or weed seeds will promote tearing from the eyes and shedding of the bacteria (M. bovis, M. bovoculi) by a few “carriers” in the herd. These carriers then spread the organism by contact and via face flies to the rest of the herd. As a result, susceptible animals may become infected and develop clinical pinkeye.
Foxtails or plant awns. Eye irritation can be caused by tall grasses as mentioned above; however, another common plant product (foxtails) can cause significant irritation. These foxtails, or other weed seeds or awns that stick in the eye, lodge in the eyes of cattle and can cause significant damage, irritation, and watering (tearing) of the eye. This can lead to further spread of the bacteria that cause pinkeye. Face flies that are attracted to this tearing can easily spread the pinkeye organisms between animals. Cattle examined for pinkeye should also be examined for the possible presence of these foxtails or plant awns. If they are found, they must be removed.
One clue to the presence of foxtails is the location of the damage in the eye. With uncomplicated pinkeye the damage usually begins in the center of the eye and spreads outward. With a foxtail or other foreign body the damage will be “off-center." The examination of the eye for foxtails and pinkeye creates another opportunity for spread of the disease and this spread must also be prevented.
Use disposable latex gloves. When examining the eyes always use disposable latex gloves. The pinkeye agents will bind to your hands and you can become a very effective transmitter of the disease. So you can become a “giant face fly” in terms of causing more problems in your herd. When you do treat a pinkeye animal be sure to use disposable needles and syringes—then dispose of them!
Keep your clothing clean. Just as with your hands, your clothing can easily become contaminated with the pinkeye agents. Therefore, it is best to treat any pinkeye or potential pinkeye cases after you have done all the routine animal handling procedures on healthy animals for the day. Alternatively, change clothes after handling pinkeye cattle and before handling normal cattle.
Disinfectants. The routine use of a disinfectant for any equipment used on animals with pinkeye is necessary. Nolvasan (chlorhexidine; Fort Dodge) is an excellent choice because it is not irritating to tissues and works well as a disinfectant. Your veterinarian can also suggest other disinfectants that will accomplish this goal. Things to be disinfected include (1) forceps, hemostats, or tweezers used to remove foxtails, (2) nose tongs for restraint, or (3) rope or nylon halters. It may be a good idea to clean and disinfect the head catch or head restraint area of the chute as it may be an area of contamination and spread of the agents.
Your veterinarian. This may be the most important part of your prevention plan. Get your veterinarian’s advice about prevention before the outbreak or if you had problems last year, seek their advice ahead of time. Topics to be covered should include (1) fly control, (2) vaccines, (3) disinfectants, (4) tools and supplies to have on hand for prevention and treatment, and (5) treatment protocols and any necessary prescriptions.