Adequate Medical Care

Welfare evaluation protocols developed for commercial production units (Global Animal Partnership, Welfare Quality, Red Tractor Assurance, Royal Society for the Prevention of Cruelty to Animals) can be modified for smaller, multiple species scenarios. Guidelines for choosing techniques to evaluate representative samples and parameters to consider can be adapted effectively. Untreated wounds, lameness, and evidence of preventive medicine are documented.

Vaccination and parasite control programs are evidenced by low fecal egg counts, veterinary receipts, and vaccination records appropriate for the species and region. To assess the adequacy of parasite control, the condition of the animals must be considered. If the BCS is adequate, then the parasite burden is not detrimental to that individual. Animals with low BCS, diarrhea, or ill thrift should have a fecal egg count (FEC) performed. The modified McMaster technique is the current gold standard for FECs in ruminant species. The results are reported in eggs per gram (epg) of feces. The acceptable epg is dependent on the species, the season, and the production stage. Horses are generally dewormed at >200 epg. Recommended levels for small ruminants during warm weather when the barber pole worm (Haemonchus contortus) is most problematic are nonpregnant adults at 2000 epg, bred females and young stock at 1000 epg, and lactating does at 750 epg. During the colder months, other species of worms (brown stomach worm [Ostertagia ostertagi] and bankrupt worm [Trichostrongylus columbriformis]') predominate that produce fewer eggs per female, so deworming should occur at one-half of the summer numbers (nonpregnant adults at 1000 epg, etc.) (Fernandez, 2012). References and videos demonstrating the technique are available online (https://www.wormx.info/fecal-egg-counting). Submission to a veterinary clinic or laboratory is also an option. If you suspect Cryptosporidium parvuum, submission to a laboratory is preferred as these organisms can be challenging to document without special staining and a trained observer. After deworming, a reduction in the egg count should be documented to demonstrate that a resistant strain of parasite is not present in the herd (Sanders, 2015). In most livestock species, internal parasites are never eliminated. If FECs are low, then the ill-thrift of the animals is likely due to another cause.

External parasites impact welfare by causing weight loss, anemia, pruritus, and alopecia. Some external parasites are USDA/APHIS reportable diseases. These include Old World screwworm (Chrysomya bezziana) and New World screwworm (Cochliomyia hominiuorax) in all livestock species, and mange in sheep and goats. Some external parasites can be visualized with the naked eye or with the aid of a hand lens, while others require skin scraping or tape prep for a definitive diagnosis. Lice tend to be species specific and spend their life cycle on the host, surviving for about a week in the environment. Transmission can be direct from animal to animal or indirect via shared grooming tools, or contaminated bedding or equipment. Lice are more numerous in the winter because they stop reproducing or die at higher temperatures. Cattle and goats are commonly infested with lice while horses, unless debilitated, are less susceptible. Affected cattle will lick themselves, leaving saliva-matted hair, while goats, horses, and pigs will rub against objects. Lice will avoid light and move into another sheltered location as the hair shafts are parted. Nits will be found attached to the hair/feathers. Nits can be collected in a glass vial with or without alcohol. Lice can be photographed on the animal with a macrolens and/or images taken from a microscope slide to demonstrate the biting or sucking mouthparts that aid in identification

Figure 17.10 Pig with scabies and lice. Note red, thickened skin, hyperplastic gray areas on snout, regions of alopecia, and evidence of self-trauma.

of the species. Nits on the hair will demonstrate that lice have had sufficient time to reproduce (20-40 days). Poultry can be infested with several species office simultaneously—40 species have been identified to date including, most commonly, the body louse (Menacanthus stramineus), head louse (Culclotogaster heterographa), and the shaft louse (Menopon gallinae), which deposits nits on the base of the feather shaft. Light burdens are common and not detrimental. Heavy burdens can cause anemia, feather loss, and ill-thrift. The northern fowl mite/feather mite (Ornithonyssus sylvarium) will cause soiled feathers on the ventrum of the bird (vent, tail, legs). Red mites (Dermanysus galllinae) feed on the birds at night and then seclude themselves in the hen house during the day. Heavily infested birds will lose weight. Providing the birds with a dust bath containing diatomaceous earth, wettable sulfur powder, or sand will control the external parasite load (Martin and Mullens, 2012). Pigs with scabies {Sarcoptes scabei var suis) will rub against objects, lose hair, and develop thickened skin (Figure 17.10 and Table 17.6).

Regionally, the Cooperative Extension Service, the state veterinarian, or local livestock veterinarians can offer guidance regarding minimum vaccination requirements for that area. Receipts from online veterinary supply and local feed stores may document vaccine purchases. The farm veterinarian may have administered or dispensed vaccine. Biologicals should be stored in the refrigerator at a controlled temperature. The presence of a preventable disease in the flock/ herd should be documented in conjunction with the amount of vaccine purchased and evidence of timely administration.