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Single strains of 5 different P. haemolytica serotypes (1, 2, 5, 6 and 9) and an untypable strain were compared in an attempt to detect differences which might be related to virulence. All but the untypable strain caused extensive lesions when injected into the lungs of healthy cattle. Each strain was found to be encapsulated and to be toxic in vitro for bovine leukocytes. Each strain also produced leukotoxin in vitro. The toxins varied, however, in total toxic activity and in the kinetics of leukotoxin production. Vaccination of cattle with each of the serotype strains elicited antibodies to organism somatic antigens and, to various degrees, the production of leukotoxin-neutralizing antibodies which showed no strain specificity in cross-neutralization studies. Although each of the serotype strains appeared to be a potential bovine pathogen, subtle differences were observed which may explain the importance of Serotype 1 strains in bovine pneumonic pasteurellosis. 相似文献
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Thirty-nine adult light horse mares, geldings, and stallions were used in two experiments to assess the pituitary hormone and insulin responses to infusions of arginine, aspartic acid, lysine, glutamic acid, and N-methyl-D,L-aspartate (NMA). In Exp. 1, 27 horses were assigned to one of three infusion treatments: 1) physiological saline (1 L); 2) 2.855 mmol of arginine/kg BW in 1 L of water; or 3) 2.855 mmol of aspartic acid/kg BW in 1 L of water. In Exp. 2, 12 horses were assigned, in a multiple-square 4 x 4 Latin square design, to one of four infusion treatments: 1) 2 mL of saline/kg BW; 2) 2.855 mmol of lysine/kg BW in water; 3) 2.855 mmol of glutamic acid/kg BW in water; or 4) 1 mg of NMA/kg BW in water. In Exp. 1, an acute (within 20 min) release of growth hormone (GH) was induced (P = 0.002) by aspartic acid. In contrast, acute release of prolactin (P = 0.001) and insulin (P = 0.002) was induced only by arginine; moreover, the arginine effect on insulin was present only in mares (P = 0.011). In Exp. 2, an acute release of GH was induced (P = 0.001) by glutamic acid and NMA. In males, the glutamic acid-induced GH release was greater than that of NMA; in mares, the NMA-induced GH release was greater than that of glutamic acid (P = 0.069). Both lysine and glutamic acid induced (P = 0.001) acute release of prolactin, whereas an acute release of insulin was elicited (P = 0.002) only by lysine. The NMA-induced LH response was due almost entirely to the response in mares and stallions (P = 0.016), and the NMA-induced FSH release was due almost entirely to the response in mares (reproductive status effect; P = 0.004). In the horse, aspartic acid, glutamic acid, and NMA seem to stimulate GH release; arginine and lysine seem to stimulate prolactin and insulin release; and NMA seems to stimulate LH and FSH release. It seems that N-methyl-D-aspartate glutamate receptors are involved in controlling GH, LH, and FSH secretion, whereas other mechanisms are involved with prolactin secretion. These results also indicate that gonadal steroids interact with amino acid-induced pituitary hormone release in adult horses. 相似文献
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Heather L Reid Sharon L Deem Scott B Citino 《Journal of zoo and wildlife medicine》2005,36(3):523-526
A 6-yr-old maned wolf (Chrysocyon brachyurus) was diagnosed with an extraosseous osteosarcoma on the lateral aspect of the right thigh. Antemortem radiography revealed a calcified mass with no skeletal involvement. The mass was excised, but visible regrowth of the tumor was evident within 5 wk. Histologic examination and immunohistochemistry, including staining for p53 tumor suppression gene protein, were performed on the excised mass. The maned wolf was euthanized 13 wk after the initial diagnosis. The neoplasm was located in a site commonly used for the delivery of intramuscular injections, including vaccinations. Although no definitive association can be made, it is worth noting this relationship, as vaccine-site neoplasias have been observed in other species, most notably the domestic cat (Felis domesticus). 相似文献
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Christopher S Hanley Heather A Simmons Roberta S Wallace Victoria L Clyde 《Journal of zoo and wildlife medicine》2005,36(3):515-519
A 10.5-yr-old male spotted hyena (Crocuta crocuta) developed acute, severe erythematous and ulcerative dermatitis of the hindquarters, feet, face, and ears 19 days after receiving a recombinant canary pox vectored canine distemper vaccine. Biopsies of the lesions supported a diagnosis of erythema multiforme (EM), which is an immune-mediated disorder that can occur days to months after exposure to antigenic stimuli. During the lengthy recovery, esophageal regurgitation and ulceration developed either as complications of the disease or secondary to therapy. The esophageal disease was managed with metoclopramide, sulcrafate, omeprazole, and frequent feedings. The distemper vaccine is postulated to have been the inciting cause of EM in this animal. 相似文献
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Wilson GH Greene CE Greenacre CB 《Journal of the American Veterinary Medical Association》2003,222(8):1093-6, 1077
A 1.5-year-old ferret examined because of seizures was found to have low serum calcium, high serum phosphorus, and extremely high serum parathyroid hormone concentrations. Common causes of these abnormalities, including nutritional secondary hyperparathyroidism, chronic renal secondary hyperparathyroidism, tumor lysis syndrome, and hypomagnesemia, were ruled out, and a tentative diagnosis of pseudohypoparathyroidism was made. Pseudohypoparathyroidism is a hereditary condition in people that, to our knowledge, has not been identified in ferrets previously and is caused by a lack of response to high serum parathyroid hormone concentrations, rather than a deficiency of this hormone. The ferret improved after treatment with dihydrotachysterol (a vitamin D analog) and calcium carbonate. It was still doing well after 3.5 years of continued treatment. 相似文献