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121.
The presence and numbers of bovine herpesvirus 4 (BoHV-4) infected CD11b+ leukocytes were investigated during experimental infections of New Zealand White rabbits by Fluorescence Activated Cell Sorter (FACS) analysis. Peripheral blood leukocytes (PBL) were collected every second day, and the cells were stained with phycoerythrin-labelled CD11b-specific mouse monoclonal antibody and fluorescein-conjugated bovine herpesvirus 4-specific mouse monoclonal antibody. The numbers of double-stained cells from PBLs of the control and inoculated groups were measured and compared in FACSTREK analyser. Double-stained cells were detected in the virus-inoculated group on postinoculation days (PID) 2-5 and 9-12. The results indicated that CD11b+ PBLs were permissive for BoHV-4 infection, and are probably the main reservoir of the virus during the latent period. The data did not indicate production of infectious viral particles, but virus-specific proteins were expressed on the surface of CD11b+ cells. The two waves of double-stained cells gave similar results to the PCR assays from serum samples, which showed the presence of viral DNA in the serum on the same days when virus-infected CD11b cells were also present. Productive BoHV-4 infection of mast cells or undifferentiated leukocytes in the bone marrow and the antiviral immune response might be responsible for this periodic appearance of the virus in CD11b+ PBLs and in the serum. The paper provides evidence that CD11b+ PBLs are the main target cell populations in the blood for BoHV-4. 相似文献
122.
123.
S. Avendaño J.A. Woolliams & B. Villanueva 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2005,122(5):302-308
This study describes a general framework for predicting the accuracy of Mendelian sampling terms when truncation selection is applied on best linear unbiased prediction (BLUP) estimated breeding values. A selection index approach is followed. The pseudo‐BLUP index is extended to include terms related to the Mendelian sampling term. Predicted accuracies are compared with those obtained through stochastic computer simulation. Good predictions for the accuracy of the Mendelian sampling term were obtained both at selection time and at convergence of long‐term contributions of selected candidates for a range of heritabilities and population structures. The prediction approach developed provides a key tool for obtaining predictions of genetic response from quadratic optimization that maximizes the rate of genetic progress while restricting the rate of inbreeding. 相似文献
124.
Fluctuation in the concentration of sex steroids and aflatoxin B1 in the seminal plasma of boars and its relation to sperm production 总被引:1,自引:0,他引:1
The concentration of testosterone, 17-beta oestradiol and aflatoxin B1 were studied in the semen plasma of 21 boars of four breeds for the period of twelve months. The following spermiological parameters were investigated: semen volume, sperm concentration, percentage of abnormal spermatozoa, and survival of spermatozoa. The fertilizing capacity of ejaculates was evaluated according to the conception rate of sows and gilts after the first insemination, according to the average number of piglets per litter and average number of live-born piglets per litter. The highest aflatoxin B1 residues in sperm were recorded in March to May and were related with aflatoxin concentration in feed ration. The group of boars with fertility disorders had more aflatoxin in their sperm (up to 100 pmol . l-1), lower sperm concentration, lower survival of spermatozoa, and a larger proportion of abnormal spermatozoa. The year season had a significant influence on the concentration of the hormones. The highest average value of testosterone (10.2 +/- 1.28 nmol) was obtained in autumn and lower values were recorded in winter. The changes in 17-beta estradiol concentration were similar to the changes in testosterone content, with the maximum value in November (0.249 nmol X 1(-1]. The boars with reproduction disorders had a significantly lower concentration of 17-beta oestradiol. Significant correlations were found between the concentration of the hormones, semen volume, and sperm concentration. 17-beta oestradiol also had a significant positive correlation to abnormal spermatozoa and to the activity of aspartate aminotransferase. 相似文献
125.
Ballent M Lifschitz A Virkel G Sallovitz J Maté L Lanusse C 《Veterinary journal (London, England : 1997)》2012,192(3):422-427
The impact of an efflux pump-related interaction between ivermectin and danofloxacin on their intestinal transport (ex vivo) and disposition kinetics (in vivo) was assessed. Eighteen male Corriedale sheep were randomly assigned to one of three groups. Animals in Group A received 0.2mg/kg ivermectin by SC injection, those in Group B were given 6 mg/kg danofloxacin SC on two occasions 48 h apart and those in Group C were treated with both compounds at the same rates. Plasma concentrations of ivermectin and danofloxacin were measured by HPLC using fluorescence detection. Ex vivo intestinal drug transport activity was measured by the use of the Ussing chamber technique. Plasma concentrations of ivermectin in the first 6 days after injection tended to be higher in Group C than Group A. Contemporaneous treatment with ivermectin significantly increased systemic exposure to danofloxacin (AUC values were 32-35% higher) and prolonged the elimination half-life of danofloxacin (40-52% longer). Ex vivo, incubation with ivermectin significantly decreased the efflux transport of rhodamine 123, a P-glycoprotein substrate, in sheep intestine, but no significant effect of danofloxacin on transport activity was observed. Evaluation of the interaction of danofloxacin with the breast cancer resistance protein (BCRP) showed that pantoprazole and ivermectin significantly decreased danofloxacin secretion in the rat intestine. Thus, the ivermectin-induced reduction of danofloxacin efflux transport observed in this study may involve BCRP activity but the involvement of P-glycoprotein cannot be ruled out. 相似文献
126.
Gremião I Schubach T Pereira S Rodrigues A Honse C Barros M 《Australian veterinary journal》2011,89(9):346-351
OBJECTIVE To describe the use of intralesional amphotericin B in localised lesions for the treatment of 26 cats from Rio de Janeiro, Brazil, with sporotrichosis refractory to oral itraconazole. DESIGN Uncontrolled intervention study. METHOD The 26 cats in this study were diagnosed with sporotrichosis, confirmed by isolation of Sporothrix schenckii, and presented residual localised skin lesions refractory to treatment with oral itraconazole for a minimum period of 8 weeks. The animals received weekly applications of intralesional amphotericin B in conjunction with oral itraconazole. In cases of owner unavailability, a maximum of 2 weeks between the infiltrations was accepted. RESULTS Twenty-two (84.6%) of the 26 treated cats achieved clinical remission, 16 (72.7%) of which were cured, and in the remaining six (27.3%) the lesions recurred at the same site. Lack of clinical response was observed in one animal and three owners abandoned treatment. CONCLUSION The proposed therapeutic regimen is an adjunctive treatment option for cats with sporotrichosis presenting as residual skin lesions refractory to itraconazole. 相似文献
127.
Histochemical and ultrastructural studies were performed on the lateral musculature from individual female whitemouth croaker, Micropogonias furnieri, at the anterior, medium and posterior regions. Based upon histochemical myosin-ATPase (m-ATPase) determination, diverse types of red, pink and white fibres were discerned. Red muscle had abundant mitochondria and stained intensely for aerobic enzymes, white muscle scarcely stained for the same enzymes and pink muscle responded in an intermediate manner. Both white and pink muscle had few mitochondria. The relative proportion of red muscle increased towards the caudal region; pink muscle diminished towards this region and white muscle modified its proportion only in the anterior region. m-ATPase activity showed differences in relation to the gonadal condition along the body, particularly in the white fibres at the anterior and medium regions. 相似文献
128.
Effect of aflatoxin on performance, hematology, and clinical immunology in lambs. 总被引:2,自引:0,他引:2 下载免费PDF全文
Twenty-four female lambs were intoxicated with a diet contaminated with 2 ppm aflatoxin for a period of 37 d. Twelve lambs were maintained as the control group. After this period, the lambs were left for 35 d without aflatoxin in their feed. Performance, hematology and clinical immunology were examined in the intoxicated lambs. A non-significant decrease in body weight was observed in the intoxicated lambs during the intoxication period, whereas a significant decrease (P<0.001) in average daily gain was noted on the last day of intoxication and during the clearance period. No significant differences were observed in erythrocyte count, white blood cell count or differential leukocyte count between the groups. Bacteriostatic activity of the serum was lower in the intoxicated lambs, however, there was no effect on serum opsonic activity. Phagocytosis by the neutrophils was higher during the intoxication period and the levels of IgG were elevated in the intoxicated lambs. In vivo cellular immunity was assessed by intradermal injection of phytohemagglutinin; the response was lower during intoxication period. These results indicate that a lowering in the average daily gain was the most sensitive indicator of aflatoxicosis in lambs, and that the immune response was altered, which could render the animals more susceptible to infectious diseases. 相似文献
129.
This paper reviews the epidemiology of bovine, swine, ovine, caprine, and canine brucellosis in Brazil. The zoonotic aspects of Brucella infection in Brazil is also discussed. Emphasis is given to the new program for the control of brucellosis in cattle and buffaloes that is likely to provide important insights into the prospects and strategies for controlling brucellosis in developing countries. 相似文献
130.
E Pinart S Bonet M Briz L M Pastor S Sancho N García E Badia J Bassols 《Veterinary journal (London, England : 1997)》2002,163(1):68-76
The present study describes the glycosidic content of the interstitial tissue in testes from healthy boars and from unilateral and bilateral abdominal cryptorchid boars using lectin histochemistry. The Leydig cells of healthy boars contained glycans with fucosyl, mannosyl, glucosyl, neuraminic acid and galactosyl residues, which have structural and transport functions, and participate in androgen synthesis and in cell regulation. Unilateral cryptorchidism induced high glucosyl and low galactosyl content in the Leydig cells of scrotal testes, resulting in impaired androgen production. In abdominal testes, the Leydig cells exhibited increased amounts of glucosyl and reduced amounts of galactosyl and neuraminic acid residues, resulting in defective cell regulation and lack of androgen synthesis. In healthy boars, the extracellular glycans contained fucosyl, galactosyl, glucosyl and neuraminic acid residues, which confer viscoelasticity on the interstitial tissue and participate in substrate transport, hormone binding and cell-cell interaction. Unilateral cryptorchidism did not induce anomalies in extracellular glycans in scrotal testes, but unilateral and bilateral cryptorchidism resulted in an increased content of fucosyl and galactosyl, and a decreased content of glucosyl and neuraminic acid residues in abdominal testes, leading to reduced viscoelasticity and defective substrate transport across the extracellular matrix. 相似文献