Risks of Disease Transmission: Safer Shearing
General concepts:
The information provided in this fact sheet is common sense, and much of it you probably already know. But after reading this, you may develop a careful, systematic approach to avoiding the spread of disease. This will help promote your professional status, and keep your clients happy.
You are going to handle every animal, and you have a great chance to see problems the owner may not have seen. You can help prevent problems by first, asking the owner:
- to sort out sheep with any “lumps” so you can handle them last. These might be CL, and you don’t want to spread it. Try not to rupture the abscess. If you find an abscess while you are shearing STOP AND DISINFECT your equipment and hands. If you can, put on clean coveralls before doing any more sheep. Advise owner to separate out all sheep with abscesses, and consider laboratory diagnosis, treatment, vaccine against CL, and/or culling these.
- handle and shear sheep from youngest to oldest, if possible. This way, you shear those most likely to be healthy first. This lessens the chance of spreading disease.
- do they want you to trim hooves? If so, trim after shearing. Advise the owner if you see hoofrot or hoofscald to mark or sort out, and then treat, these animals. Disinfect hoof trimmers after trimming animals with footrot/scald.
- are you shearing rams? Be sure to check the scrotum and the prepuce for lumps, uneven size, flystrike, etc. Let the owner know if you find a problem.
Time between farm visits:
If you can, try to schedule a day without any animal contact between farm visits. This allows any viruses or bacteria that might be on your vehicle, equipment, clothing or self to die (because there are no sheep, their favorite hosts, to support them). If you can’t:
- Clean the vehicle: If you are quite busy and can’t schedule a break between farms (or if you have your own animals at home), then be doubly careful about disinfection between flock visits. How? Start with the tires. After leaving a farm, or before entering a new one, find a place with a hose and drain (like a gas station). Use a long handled scrub brush and soap up the tires, then rinse them well. Better yet, simply go through the car wash.
- Clean clothes/coverall: Change into a clean shirt, gloves and coveralls between farms. Put dirty clothes into a plastic sack, and then launder separately from other clothing as soon as possible. Remember, though line drying is great, driers are much more effective at killing ticks on clothing.
- Clean boots: If your boots are washable, clean them with a disinfectant (mud and manure carry germs: be sure to remove them from the soles!). If your boots are leather/fabric, at least brush them off and use a spray such as Lysol to disinfect.
- Clean hands: If you work bare-handed, wash your hands well, and keep a hand sanitizer in your vehicle for use when there aren’t good hand washing facilities provided.
Who you bring:
Coworkers and children: make sure they do what you do. You’re responsible for their actions on the farm. Dogs are an essential part of working sheep, but be sure that they don’t act as vectors of disease. Dogs working with sheep should be wormed for tapeworms every 2 months, as sheep can become infected with several kinds of tapeworms from grazing near dog fecal material that carries tapeworm eggs. Dogs can also become infected with tapeworms by eating uncooked sheep intestines/offal. Keep your dog under your control, or at home.
Equipment:
Shearing equipment may carry ectoparasites, such as keds or lice, from sheep to sheep. In addition, the bacteria that causes caseous lymphadenitis, or CL, can be spread by nondisinfected clippers and shears. It’s vital to disinfect the equipment between farms, and best to disinfect between sheep.
Handling sheep:
Shearing is hard work, though an excellent shearer makes it look easy. The less trauma to the animal, the less chance of disease transmission. The quieter and more relaxed the animal, the easier your job will be, too.
After you shear:
Clean and disinfect your equipment as you put it away. Put coveralls into plastic bags or Tupperware type bins for cleaning later. Remember to wash the tires or whole vehicle after you leave the farm. It may be a good idea to stop by the carwash between farms.
Selecting and using disinfectants:
- Nicks on sheep: tamed iodine (“Betadine”) solution; dilute per label directions.
- Bleeding hooves: untamed iodine (7% iodine) or blood-stop (“styptic”) powder.
- Deep cuts: advise owner to suture and to use antibiotics; you may clean with Betadine.
- Boots/vehicle: dilute bleach solution (10 tablespoons bleach per gallon of water).
- Clippers: Clippercide or similar bacteriocidal spray designed for clippers.
- Clothing: regular, HOT water washing and DRYING at the “high” heat setting will kill viruses, bacteria and parasites. (This is also very effective against ticks and fleas in animal bedding).
- Other: Nolvasan™ (chlorhexidine) solution is generally effective, but don’t overdo the use of disinfectants when simple washing and drying will do. Dilute per label directions.