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61.
62.
Meat regulations also involve game inspection. This publication deals with the regulations concerning furred game intended for slaughter and furred game hunted for food. 相似文献
63.
R D Park 《Veterinary Clinics of North America: Equine Practice》1989,5(1):47-66
A complete radiographic examination of the equine foot consists of properly exposed, processed, and positioned radiographs. For radiographic interpretation, in addition to knowing radiographic signs of disease, a knowledge of normal radiographic anatomy and possible insignificant anatomic variations is necessary. 相似文献
64.
Efficacy of ivermectin treatment (0.2 mg/kg) against 28-day experimental infections of Parascaris equorum was determined in 18 pony foals6–17.5 weeks old. There were 6 foals in each group: nontreated control, ivermectin injectable or oral paste. In comparison with larvae found in the nontreated controls, ivermectin injectable or paste was 96.0% and 99.9% efficacious. There was a distinct difference in drug effect against the larger (ca 26mm.) vs the smaller (13–19mm) larvae by the 2 formulations of ivermectin. There were no adverse signs related to treatment of the young foals. 相似文献
65.
T R Thedford L W Johnson 《Veterinary Clinics of North America: Food Animal Practice》1989,5(1):145-157
Although there are notable infectious conditions that are capable of producing clinical disease in the NWC, overall, these species are quite healthy. Of the bacterial diseases, enterotoxemia caused by Clostridium perfringens types C and D would be deemed the most significant in North America, while type A also would be regarded as important in South America. Other important bacterial infections of potential concern are tuberculosis, Johne's disease, anthrax, malignant edema, actinomycosis, tetanus, and the South American condition referred to as alpaca fever, which, to date, has not been observed in North America. Fungal infections include classical ringworm, principally caused by Trichophyton spp., and the cases of coccidioidomycosis that are associated with the arid desert lands of the southwestern United States. Most notable of naturally occurring viral infections in the NWC would be rabies, ecthyma, and a recently described blindness neuropathy that has been associated with the equine herpesvirus I. NWC can be infected experimentally with agents causing hoof-and-mouth disease and vesicular stomatitis, but naturally occurring cases do not seem to occur. Serological evidence of exposure to many viral agents, including blue tongue, parainfluenza 3, bovine respiratory syncytial virus, bovine herpesvirus I, bovine viral diarrhea, influenza A, and rotavirus, has been demonstrated; however, no clinical disease associated with these agents, as yet, is apparent. 相似文献
66.
W Ahne J R Winton T Kimura 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(8):561-567
Infectious diseases remain one of the most important limitations to the successful propagation of aquatic animals. Most of the losses caused by pathogens in aquaculture could be prevented by health inspection, adequate environment and sound management practices. Effective control measures, mainly based upon 1) avoidance of pathogens 2) modification of the environment 3) improvement of host resistance 4) vaccination and 5) chemoprophylaxis are described. 相似文献
67.
A survey of the potential use of synthetic oligopeptides in the field of virology is given. The potential value of synthetic peptides as vaccines and diagnostic antigens is discussed. The advantages compared to conventional vaccines as well as the limitations, e.g. the poor efficiency of immune response, are described. 相似文献
68.
69.
70.
T M Frye S N Williams T W Graham 《Veterinary Clinics of North America: Food Animal Practice》1991,7(1):217-275
Deficiencies of vitamins A, D, K, E and thiamin can cause severe limitations in beef production. In particular, vitamin A and E can be common causes of lost profit, secondary to limitations of reproductive and growth potential. Prolonged dry periods will reduce available A and E in pasture forage, as can ensiling and prolonged storage of harvested feedstuffs. Polioencephalomalacia is a thiamin responsive disorder, associated with high concentrate feeding and lush pastures. Antimetabolites, such as amprolium, will cause thiamine deficiency when fed in excess. Recent information has shown improved performance with supplemental beta carotene and niacin. The positive responses in reproductive performance, noted with cattle fed supplemental beta carotene, was independent of vitamin A. Supplementation of vitamins above National Research Council recommendations can be justified. However, proper evaluation of feed and animal status, and documentation of a response to supplementation is necessary before diagnosing deficiencies of specific nutrients. 相似文献