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171.
The effects of single i.v. and p.o. doses (5 mg/kg) of fenbendazole, were evaluated on thyroxine, tri-iodothyronine, corticosterone, hematology, clinical chemistries, and serum proteins in 10 white Pekin ducks. Fenbendazole was administered i.v. (n = 5) as a 3% dimethyl sulfoxide solution and p.o. (n = 5) as a 10% commercial suspension. Serum enzyme concentrations, total protein and protein fractions, glucose, cholesterol, uric acid, sodium, and potassium were unchanged from baseline values. Serum triglycerides decreased consistently in the i.v.-treated group but remained unchanged in the p.o.-treated group. Serum chloride was consistently elevated above baseline values for both i.v.- and p.o.-treated ducks, while inorganic phosphate was consistently decreased only in the i.v.-treated group. Hemoglobin and hematocrit values generally were below baseline values. Leukocyte values varied considerably and were not significantly different from baseline values. Serum thyroxine and tri-iodothyronine values in both the i.v.- and p.o.-treated groups were not changed significantly from baseline values. Serum corticosterone values were not changed in the i.v.-treated groups but they were decreased at various times in the p.o.-treated group. Although there were some sporadic significant changes in the parameters measured versus baseline values all values remained within the physiologic limits for ducks. The safety of fenbendazole has been previously demonstrated for several species.  相似文献   
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A 14-year-old domestic shorthaired cat was presented because of swelling of the digits and lameness. A solitary lung mass was observed on thoracic radiographs. Clinical and pathological evaluation confirmed a primary pulmonary squamous cell carcinoma metastatic to a single digit on each foot. Other metastatic lesions were present in the left popliteal lymph node and in the left iliac vein.  相似文献   
174.
Thirteen Standardbreds had subchondral lucency of the third carpal bone (C3), described as single or multiple central areas of C3 bone loss in the radial fossa. Sclerosis of the radial fossa was also detected. The mean age of 9 stallions, 3 mares, and 1 gelding was 4.1 years (range, 3 to 7 years). All horses had an acute moderate to severe lameness referable to the middle carpal joint. A dorsoproximal dorsodistal (skyline) radiographic projection was most useful and identified mild (3 horses), moderate (6 horses), and severe (4 horses) subchondral lucency and sclerosis of the radial fossa. The margin of C3 was intact dorsal to the lucent areas in all horses. In 12 horses, arthroscopic surgical evaluation and curettage of the lesion were performed. Of the 9 horses monitored long enough to allow racing, 8 horses (89%) returned to racing, although only 6 (75%) raced at the same degree of competition. Subchondral lucency of C3 resulted from chronic damage to C3 with subsequent osteochondral collapse or acute C3 proximal surface osteochondral fracture.  相似文献   
175.
The influences of pelleting and beta-glucanase supplementation on the digestibility of dietary components in a barley-based diet were investigated in pigs fitted with cannulas in the terminal ileum. The diet contained 49.0% starch, 18.9% crude protein and 14.8% dietary fiber, with arabinoxylans (4.9%), mixed-linked beta-glucans (3.4%) and cellulose (3.3%) as the main fiber components. Pelleting increased mixed-linked beta-glucan solubility from 45 to 62%. Neither treatment influenced the ileal or fecal apparent digestibilities of dry matter (64 and 80%, respectively), energy (62 and 79%), crude protein (53 and 75%), crude fat (26 and 27%) or dietary fiber (58 and 72%). However, pelleting increased (P less than .01) the pre-ileal apparent digestibility of starch from 91.5 to 95.3% and decreased (P less than .03) that of ash from -10 to -23%, while increasing (P less than .005) the fecal apparent digestibility of starch from 98.6 to 99.7%. The solubility of mixed-linked beta-glucans in ileal digesta was lower (P less than .001) in pelleted (26%) than in unpelleted (58%) diets. beta-glucanase supplementation also increased (P less than .05) the ileal apparent digestibility of starch, from 92.6 to 94.3%, and of mixed-linked beta-glucans, from 95.7 to 97.1%. Significant between-pig differences in the apparent digestibility of dietary components were observed. In conclusion, treatments that disrupt the endosperm cell walls in barley can increase the proportion of the diet digested prior to the large intestine.  相似文献   
176.
Llama reproduction   总被引:1,自引:0,他引:1  
The reproductive anatomy, physiology, and breeding behavior of the llama is unique enough to make familiarity with it imperative. Female puberty averages 12 months, while many males are not reproductively functional until after 3 years. Proper management of a breeding pair or herd is necessary to maintain maximum reproductive performance. Proof of pregnancy is suggested by rejection of the male and may/should be confirmed by progesterone assay, rectal palpation, or ultrasound techniques. The postpartum female is notable for breeding back rapidly, with high pregnancy rates resulting. Both male and female factors enter into llama infertility, with each gender having significant incidence of reproductive anatomical abnormalities. Management as well as acquired infertility problems (heat factors, trauma, infection, neoplasia, and hormonal imbalances) contribute to the bulk of infertility cases investigated. Techniques used to diagnose infertility in llamas are quite comparable to the equine species; however, female body size and semen analysis in the male present significant challenges. The approach to therapy has been quite empirical to date, owing to lack of consistent problems and numbers to afford conclusive trials. Alterations of pregnancy include resorption, abortions, and stillbirths. Resorption between 30 to 60 days of gestation is reported regularly. Abortions caused by stress occur regularly. Infection abortions caused by leptospirosis, toxoplasmosis, and chlamydiosis are to be expected. Ponderosa pine-related abortions are suspected. In summary, I find use for a broad background in large animal theriogenology to apply to llama infertility. There no doubt are additional diagnostic techniques and therapeutic regimens that have application, and it is up to us all to keep good records and share the information.  相似文献   
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Three commonly used keratin monoclonal antibodies (MAB)--AE1:AE3, CAM 5.2, and MAK-6--were compared with routinely used cytokeratin antibody. The expression of these antibodies was analyzed in several tissues obtained from clinically normal dogs and in a variety of neoplasms from dogs. Using appropriate enzymatic digestion, paraffin-embedded tissues processed in routine manner retained their typical keratin expression. Differentiated and poorly differentiated epithelial neoplasms, lymphomas, and melanomas were studied by use of the avidin-biotin-peroxidase technique. All 4 of the aforementioned antibodies had similar staining profiles. Of 3 anaplastic carcinomas, 2 had positive reaction to all 4 antibodies. All lymphomas, plasma cell tumors, and amelanotic melanomas had negative reaction to MAK-6, CAM 5.2, AE1:AE3, and cytokeratin MAB. Three basal cell epitheliomas had positive reaction to all 4 antibodies, whereas 1 basal cell tumor with a solid pattern had negative staining reaction. Two carcinoids had negative reaction to all markers and 1 of 2 malignant chemodectomas and 1 transitional cell carcinoma had staining reaction to only AE1:AE3 MAB. Comparing the 4 antibodies, use of AE1:AE3 MAB produced the strongest staining intensity followed by cytokeratin, MAK-6, and CAM 5.2 MAB. All 4 antibodies had low background staining. In conclusion, AE1:AE3 and MAK-6 MAB are as useful as cytokeratin MAB for identification of poorly differentiated epithelial neoplasms in dogs and cats.  相似文献   
180.
Pasteurella multocida isolated from turkeys during an outbreak of fowl cholera was characterized by serotype and heterogeneity of genes encoding rRNA (ribotype) to investigate the epidemiology of the organism. Isolates were collected between October 1985 and July 1986. The M9 or Clemson University fowl cholera vaccine-like strain was detected in 17% of the flocks with fowl cholera. One particular strain, isolated only from breeder flocks, was recovered from 7 of the 10 breeder flocks examined in this study. Intracompany transmission appeared to be common, implying a failure in biosecurity. Circumstantial evidence indicated that in the field; the incubation period of P multocida in a turkey flock may be between 2 to 7 weeks. Wildlife did not appear to be an important reservoir of P multocida for turkeys during this study period. Ribotyping results tended to discount several of the possible interflock transmissions, as suggested by examination of serotyping results alone; however, serotyping in combination with ribotyping proved helpful in understanding the epidemiology of P multocida in turkeys.  相似文献   
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