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291.
Matsuzaki S Cruzana MB Budipitojo T Hondo E Watanabe G Taya K Sasaki M Kitamura N Yamada J 《Anatomia, histologia, embryologia》2001,30(6):375-378
The differential localization of the inhibin beta subunits betaA and betaB in the testis of adult bull was studied using specific monoclonal and polyclonal primary antibodies. Inhibin betaA- and betaB-subunits were localized only in the Sertoli cells. The inhibin betaA-subunit was observed in the cytoplasm while the betaB-subunit was localized in the nucleus. No specific findings depending on spermatogenic stages were observed among the seminiferous tubules. Moreover, the inhibin alpha-subunit was not detected in the testis of the bulls. In addition, no inhibin subunits were detected in the Leydig cells and spermatogenic cells. These findings indicate the presence of betaA- and betaB-subunits in the bull, which may suggest a possibility that activin is produced and/or stored in the Sertoli cells and regulates spermatogenesis in an autocrine/paracrine manner. Moreover, the inhibin betaB-subunit may be produced in the nucleus but the functional meaning of this is not yet clear. 相似文献
292.
Helminth infections are an important cause of lost productivity in livestock world-wide, often necessitating anthelmintic treatment. However, a large part of the anthelmintics are used indiscriminately because the parasite levels are too low to justify treatment or because the treatments are not correctly programmed, resulting in undertreatment or overtreatment. The objective of this paper is to discuss possible thresholds for anthelmintic treatment of some of the more important helminth infections in livestock, i.e. gastrointestinal nematodes, lungworms and liver fluke, to promote a more appropriate use of anthelmintics. When possible, a distinction is made between therapeutic thresholds, production-based thresholds and preventive thresholds. A "therapeutic threshold" is intended to identify (an) animal(s) with parasite levels that necessitate immediate treatment. The therapeutic threshold is basically the diagnosis of clinical disease, and can be determined relatively easily for the parasites discussed in this paper. A "production-based threshold" is intended to measure the effects of sub-clinical parasitism on productivity parameters, such as weight gain and milk yield, before clinical disease occurs. Finally, a "preventive threshold" is meant to predict future infection levels, to enable the application of appropriate control measures. 相似文献
293.
Response of domestic geese to lentogenic and velogenic strains of Newcastle disease virus 总被引:4,自引:0,他引:4
A total of 54 domestic white meat-type geese were included in vaccination/challenge trials to evaluate susceptibility to disease and humoral immune responses using the haemagglutination inhibition (HI) and virus neutralization (VN) tests against Newcastle disease (ND). Two groups of twenty geese, five weeks of age, were conjunctivally vaccinated with either 100 x 10(6) or 2.5 x 10(6) EID50 (egg infectious dose 50 per cent) per bird of live La Sota virus, respectively, and 14 geese remained unvaccinated. At 15 weeks of age all vaccinated geese and seven unvaccinated geese were subcutaneously injected with 0.5 ml of inactivated oil emulsion ND vaccine, whereas seven geese remained as negative controls. At an age of 20 weeks, all 54 geese were challenged with 10(8.0) EID50 per bird of the viscerotropic velogenic NDV strain Herts 33/56. Live virus application as well as the oil emulsion vaccine did not induce discernible clinical signs and have no detrimental effect on body weight gains. At days 1, 3, 5, 8, 13, 16, 20, 23 and 27 after the application of lentogenic vaccine pharyngeal and cloacal swabs were taken, after challenge samples were taken at days 2, 5 and 8. Lentogenic as well as velogenic virus were never reisolated. Low and shortlived antibody responses post vaccination were equally well measured in HI and VN tests. Only two out of seven unvaccinated but challenged geese developed signs of ND whereas all vaccinated/challenged geese remained normal but developed high to moderate levels of HI and VN antibodies. Since domestic geese do not readily excrete NDV's in detectable amounts and since they do not contain detectable amounts of the challenge virus fourteen days post challenge in their tissues the assumption is promoted that geese do not play a major role in the epidemiology of Newcastle disease. 相似文献
294.
The objective was to study associations between kinematics and ground reaction forces in the hindlimb of walking horses. Video (60 Hz) and force (2000 Hz) data were gathered for 8 strides from each of 5 sound horses during the walk. Sagittal plane kinematics were measured concurrently with the vertical and longitudinal ground reaction forces. The hindlimb showed rapid loading and braking in the initial 10% stride. The stifle, tarsal and coffin joints flexed and the fetlock joint extended during this period of rapid loading. The vertical ground reaction force showed 2 peaks separated by a dip; this pattern was similar to the fetlock joint angle-time graph. Peaks in the longitudinal ground reaction force did not appear to correspond with kinematic events. Total braking impulse was equal to total propulsive impulse over the entire stride. Flexion and extension of the hip were responsible for protraction and retraction of the entire limb. Maximal protraction occurred shortly before the end of swing and maximal retraction occurred during breakover. During the middle part of stance the tarsal joint extended slowly, while the stifle began to flex when the limb was retracted beyond the midstance position at 28% stride. Flexion cycles of the stifle and tarsal joints were well coordinated during the swing phase to raise the distal limb as it was protracted. The results demonstrate a relationship between limb kinematics and vertical limb loading in the hindlimbs of sound horses. Future studies will elucidate the alterations in response to lameness. 相似文献
295.
MMP-9 as a marker of inflammation in tracheal epithelial lining fluid (TELF) and in bronchoalveolar fluid (BALF) of COPD horses 总被引:11,自引:0,他引:11
Gelatinolytic activity was analysed to study whether elevated activity previously found at the tracheal level of the respiratory tract of horses with chronic obstructive pulmonary disease (COPD) could also be found at the lower part of the respiratory tract. Furthermore, presence and significance of the gelatinolytic matrix metalloproteinases (MMPs) MMP-2 and MMP-9 in respiratory secretions of healthy and COPD horses were determined. Elevated gelatinolytic matrix metalloproteinases were detected in bronchoalveolar and tracheobronchial secretions from COPD horses. The main pathologically elevated MMP was characterised to be MMP-9. Significantly increased MMP-9 activities as measured by gelatin zymography and Western blotting were found in all the respiratory samples from COPD horses compared to healthy horses. Elevation of active MMP-9 paralleled with increased gelatinase-associated lipocalin levels. Bronchoalveolar lavage fluid (BALF) epithelial cells, macrophages, neutrophils and lymphocytes expressed MMP-9 immunoreactivity demonstrated by immunocytochemistry and MMP-9 mRNA was expressed by bronchial epithelial cells of lung tissue section shown by in situ hybridisation. MMP-2 seems not to play a major role in chronic lung inflammation. No clear differences in MMP-2 or MMP-14 (a potent MMP-2 activator) levels were found when comparing the samples from COPD or healthy horses. These results suggests that MMP-9 could serve as a potential diagnostic marker for the active ongoing tissue remodelling in the acute phase of equine COPD. Increased gelatinolytic activity could be found at both tested respiratory tract levels. Therefore, tracheal epithelial lining fluid (TELF) samples can usefully serve as diagnostic material for detection of increased levels of the main gelatinolytic MMP, MMP-9, representing the entire diseased lung. 相似文献
296.
Kumar AM Murtaugh R Brown D Ballas T Clancy E Patronek G 《Journal of veterinary medical education》2001,28(2):73-77
A donor program for procuring dogs and cats to meet the needs of anatomical instruction was initiated six years ago at Tufts University School of Veterinary Medicine. The program was initiated in order to comply with state regulations that preclude the use of shelter animals and to satisfy ethical objections of students and faculty. The donor program has successfully met the animal needs for teaching gross anatomy and, in addition, provides opportunities to integrate clinical perspectives and ethics beginning from the first year of veterinary education. 相似文献
297.
Shelton GD Liu LA Guo LT Smith GK Christiansen JS Thomas WB Smith MO Kline KL March PA Flegel T Engvall E 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):240-244
The most common form of muscular dystrophy in dogs and humans is caused by mutations in the dystrophin gene. The dystrophin gene is located on the X chromosome, and, therefore, disease-causing mutations in dystrophin occur most often in males. Therefore, females with dystrophin deficiency or other forms of muscular dystrophy may be undiagnosed or misdiagnosed. Immunohistochemistry was used to analyze dystrophin and a number of other muscle proteins associated with muscular dystrophy in humans, including sarcoglycans and laminin alpha2, in muscle biopsy specimens from 5 female dogs with pathologic changes consistent with muscular dystrophy. The female dogs were presented with a variety of clinical signs including generalized weakness, muscle wasting, tremors, exercise intolerance, gait abnormalities, and limb deformity. Serum creatine kinase activity was variably high. One dog had no detectable dystrophin in the muscle; another was mosaic, with some fibers normal and others partly dystrophin-deficient. A 3rd dog had normal dystrophin but no detectable laminin alpha2. Two dogs could not be classified. This study demonstrates the occurrence of dystrophin- and laminin alpha2-associated muscular dystrophy and the difficulty in clinical diagnosis of these disorders in female dogs. 相似文献
298.
Takahashi K Takahashi E Ducusin RJ Tanabe S Uzuka Y Sarashina T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(2):175-178
Maximum serum thyroxine (T4) and triiodothyronine (T3) levels of healthy calves were seen at 1 day after birth, and thereafter rapidly decreased until 5 days after birth. They stabilized until 2 weeks after birth, then gradually decreased until 4 weeks after birth. Serum T4 levels of calves with endemic goiter tended to be lower than those of healthy ones, but showed similar levels to those of adult cows. T3 levels of calves with goiter were similar to those of healthy ones, but showed higher variation. T4/T3 ratio of calves with goiter were significantly lower than those of healthy ones and adult cows. While individual levels of serum T4 and T3 at just after birth could not be considered as a diagnostic index, the T4/T3 ratio could be adopted as a diagnostic index of endemic goiter. 相似文献
299.
Núñez JI Martín MJ Piccone ME Carrillo E Palma EL Dopazo J Sobrino F 《Veterinary research》2001,32(1):31-45
An analysis of the informative content of sequence stretches on the foot-and-mouth disease virus (FMDV) VPI gene was applied to two important viral serotypes: A and O. Several sequence regions were identified to allow the reconstruction of phylogenetic trees equivalent to those derived from the whole VPI gene. The optimal informative regions for sequence windows of 150 to 250 nt were predicted between positions 250 and 550 of the gene. The sequences spanning the 250 nt of the 3' end (positions 400 to 650), extensively used for FMDV phylogenetic analyses, showed a lower informative content. In spite of this, the use of sequences from this region allowed the derivation of phylogenetic trees for type A and type O FMDVs which showed topologies similar to those previously reported for the whole VP1 gene. When the sequences determined for viruses isolated in Argentina, between 1990 and 1993, were included in these analyses, the results obtained revealed features of the circulation of type A and type O viruses in the field, in the months that preceded the eradication of the disease in this country. Type A viruses were closely related to an Argentinean vaccine strain, and defined an independent cluster within this serotype. Among the type O viruses analysed, two groups were distinguished; one was closely related to the South American vaccine strains, while the other was grouped with viruses of the O3 subtype. In addition, a detailed phylogeny for type A FMDV is presented. 相似文献
300.
Neubert A Schuster P Müller T Vos A Pommerening E 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2001,48(3):179-183
Studies on the immunogenicity and efficacy of SAD B19 attenuated rabies virus vaccine in foxes under laboratory conditions were conducted. Twenty-seven foxes (Vulpes vulpes) were offered a vaccine bait containing 10(6.3) FFU/ml SAD B19. Blood samples were collected 60, 110 and 190 days post-vaccination. On day 190 post vaccination the animals and 14 controls were challenged with a canid street rabies virus. Twenty-four of the 26 vaccinated foxes (92.3%) survived the challenge, whereas all the controls died from rabies. The two vaccinated foxes that did not survive the challenge did not show any detectable level of rabies neutralizing antibodies at any time after vaccination. The geometric mean titres (GMT) of foxes that seroconverted after vaccination were 43.5, 33.9 and 43.5 IU/ml 60, 110 and 190 days post-vaccination, respectively. Furthermore, to test the vaccine virus under sub-optimal conditions five naive and nine previously vaccinated vixens received 2 ml SAD B19 (10(6.7) FFU/ml) by direct administration of the vaccine virus into the oral cavity shortly before or during pregnancy. All vixens seroconverted above the threshold of 0.5 IU/ml. No booster effect was observed in the immune response of the previously vaccinated animals. 相似文献