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81.
In a randomized double-blind clinical trial, 75 cows with ovarian cysts were treated with the synthetic gonadotropin releasing hormone, gonadorelin acetate (GnRH). Forty-two of these cows were simultaneously treated with cloprostenol (CP), and the remaining 33 cows received sterile saline. Milk progesterone (P4) was measured at treatment and two days later. Clinical response 30 days after treatment was determined by palpation per rectum, and estrus and breeding dates were recorded up to 90 days after treatment. Cows were examined for pregnancy by palpation per rectum 40 days or more after breeding. Milk progesterone levels two days after treatment were significantly lower and the 30-day clinical response rate was significantly higher in the GnRH + CP group than in the GnRH group. Intervals to first estrus and to conception, proportion in heat by day 21 after treatment, and pregnancy rate by 90 days did not differ significantly between the groups. The same relationships held in a subset of cows with P4≥1 ng/mL at treatment. Fewer cows in the GnRH + CP group became pregnant by day 90 after treatment, but this difference was not significant. These results suggest that simultaneous GnRH and cloprostenol treatment of all cows with cystic ovaries cannot be recommended at this time.  相似文献   
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Rostral and middle cranial fossa tumors affecting the optic chiasm and resulting in acute visual deficits were diagnosed in 7 dogs and 1 cat. Blindness and dilated nonresponsive pupils were the primary signs in all animals. Other concurrent neurologic deficits were either absent or were equivocal. Behavioral changes, including signs of depression and lethargy, were noticed in 1 dog and the cat subsequent to the onset of blindness. Retinal function was assessed as normal by electroretinography in all animals. The histologic necropsy diagnosis was pituitary carcinoma in 1 dog and the cat and paranasal sinus carcinoma with intracranial extension in 1 dog. A cytologic diagnosis of polycentric lymphosarcoma affecting the optic chiasm was diagnosed in 1 dog. In the remaining 4 dogs, results of computed tomographic imaging or endocrine function testing suggested pituitary gland neoplasia. Four dogs were treated with cobalt-60 radiation or chemotherapy. There was partial return of visual function in only 1 of the dogs treated with radiation.  相似文献   
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Abstract

Extract

Sir:— In the recent letter from N. Inglis,(1) Inglis, N. 1984. Leptospira icterohaemorrhagia infection in deer. N.Z. vet. J., 32: 179179. [Taylor &; Francis Online], [Web of Science ®] [Google Scholar] an infection by Leptospira icterohaemorrhagiae in deer is postulated on the basis of serological evidence. Results of antibody testing with other serovars of Leptospira would be most informative and would reveal cross-reactions, which are known to occur freyuently. Further, the strain of L. icterohaemorrhagiae antigen and the type of test used would be of great interest to readers. Seroconversion to L. icterohaemorrhagiae serovar copenhageni, has been well documented since 1951.(2) Kirschner, L. and Gray, W.G. 1951. Leptospirosis in New Zealand. Infection with Spirochaela in animals and man. N.Z. med. J. L. No. 278, : 342342.  [Google Scholar]  相似文献   
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Ninety-five avian pathogenic Escherichia coli (APEC) isolates recovered from diagnosed cases of avian colibacillosis from North Georgia between 1996 and 2000 were serotyped and examined for typical virulence-factors, susceptibility to antimicrobials of human and veterinary significance, and genetic relatedness. Twenty different serotypes were identified, with O78 being the most common (12%). The majority of the avian E. coli isolates (60%), however, were non-typeable with standard O antisera. Eighty-four percent of isolates were PCR positive for the temperature-sensitive hemagglutinin (tsh) gene and 86% positive for the increased serum survival (iss) gene. Multiple antimicrobial-resistant phenotypes (> or =3 antimicrobials) were observed in 92% of E. coli isolates, with the majority of isolates displaying resistance to sulfamethoxazole (93%), tetracycline (87%), streptomycin (86%), gentamicin (69%), and nalidixic acid (59%). Fifty-six E. coli isolates displaying resistance to nalidixic acid were co-resistant to difloxacin (57%), enrofloxacin (16%), gatifloxacin (2%), and levofloxacin (2%). DNA sequencing revealed point mutations in gyrA (Ser83-Leu, Asp87-Tyr, Asp87-Gly, Asp87-Ala), gyrB (Glu466-Asp, Asp426-Thr), and parC (Ser80-Ile, Ser80-Arg). No mutations were observed in parE. Twelve of the quinolone-resistant E. coli isolates were tolerant to cyclohexane, a marker for upregulation of the acrAB multi-drug resistance efflux pump. Quinolone-resistant isolates were further genetically characterized via ribotyping. Twenty-two distinct ribogroups were identified, with 61% of isolates clustering into four major ribogroups, indicating that quinolone resistance has emerged among multiple avian pathogenic E. coli serogroups and chromosomal backgrounds.  相似文献   
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Plant Foods for Human Nutrition - Concerns about the nutritional and sensory qualities of gluten-free (GF) products has generated interest in the evaluation of novel gluten-free ingredients. Folate...  相似文献   
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A growth model is developed for coho salmon which accounts for temperatures and feeding rates typically encountered in fish hatchery operation. Feeding rates utilized by the model ranged from maintenance to maximum utilizable rations. The model is derived from an empirical equation for maximum growth rate, and a theoretical equation for net energy utilization. The resultant equation is modified to improve fit at higher feeding levels. Calibration is accomplished with experimentally obtained data.

The model is similar to one developed by G.D. Stauffer, but represents an improvement because points on the growth curve between maintenance and maximum ration can be fitted even if maintenance and maximum requirements are obtained independently.  相似文献   

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