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71.
Epithelial response to experimentally introduced intraluminal bacteria in the avian epididymal ducts
The response of the epithelial cells of the various ducts of the avian epididymis, whose function is poorly understood, to intraluminal bacteria was evaluated by the injection of an avirulent strain of Salmonella gallinarium into the RT for 24 h. Ultrastructurally, bacteria and invading mononuclear cells were present in the lumina of the RT, proximal efferent ducts (PED) and distal efferent ducts. However, only the non-ciliated (Type I) cells of the PED epithelium ingested bacteria from the lumen. Fragments of bacteria also occurred in several intercellular spaces in the epithelium of the PED. Some mononuclear cells also contained fragments of bacteria. Neither cell death in the various epithelia nor mononuclear infiltration of the periductal tissue occurred. Therefore, in addition to the established function of absorbing most of the testicular fluid entering the epididymis, the Type I cells also appear capable of recognising and removing foreign particulate matter from the epididymal through-flow in the proximal part of the epididymis. 相似文献
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73.
Santamaría S Bobbert ME Back W Barneveld A van Weeren PR 《American journal of veterinary research》2004,65(7):938-944
OBJECTIVE: To quantify variation in the jumping technique within and among young horses with little jumping experience, establish relationships between kinetic and kinematic variables, and identify a limited set of variables characteristic for detecting differences in jumping performance among horses. ANIMALS: Fifteen 4-year-old Dutch Warmblood horses. PROCEDURE: The horses were raised under standardized conditions and trained in accordance with a fixed protocol for a short period. Subsequently, horses were analyzed kinematically during free jumping over a fence with a height of 1.05 m. RESULTS: Within-horse variation in all variables that quantified jumping technique was smaller than variation among horses. However, some horses had less variation than others. Height of the center of gravity (CG) at the apex of the jump ranged from 1.80 to 2.01 m among horses; this variation could be explained by the variation in vertical velocity of the CG at takeoff (r, 0.78). Horses that had higher vertical velocity at takeoff left the ground and landed again farther from the fence, had shorter push-off phases for the forelimbs and hind limbs, and generated greater vertical acceleration of the CG primarily during the hind limb push-off. However, all horses cleared the fence successfully, independent of jumping technique. CONCLUSIONS AND CLINICAL RELEVANCE: Each horse had its own jumping technique. Differences among techniques were characterized by variations in the vertical velocity of the CG at takeoff. It must be determined whether jumping performance later in life can be predicted from observing free jumps of young horses. 相似文献
74.
75.
Hormonal responses to acute exercise, training and overtraining. A review with emphasis on the horse 总被引:1,自引:0,他引:1
de Graaf-Roelfsema E Keizer HA van Breda E Wijnberg ID van der Kolk JH 《The Veterinary quarterly》2007,29(3):82-101
Overtraining is an imbalance between training and recovery leading to symptoms associated with a neuroendocrine dysbalance called the overtraining syndrome, a disease characterized by behavioral, emotional and physical symptoms similar with depression. Although the prevalence of overtraining is high in human and equine athletes, at present no sensitive and specific test is available to prevent or diagnose overtraining. Nowadays, it is believed that combination of different (hormonal) parameters appear to be the best indicators of overtraining. Therefore, this review provides a summary of previous literature examining the response of the hypothalamic-pituitary-adrenal (HPA) axis and the growth hormone-insulin-like growth factor-I (GH-IGF-I) axis to acute and chronic exercise as well as overtraining in humans and horses. The exercise induced hormonal responses seem to be equal for the equine as well as the human athlete, which makes comparisons possible. Repeated bouts of exercise are suggested to provide a way to detect subtle changes in hormonal responses in the individual athlete, which may make them an important tool in detecting early overtraining. This should be combined with corticotropin releasing hormone (CRH) stimulation tests and basal ACTH and GH pulsatility determination. Further research is needed to establish the correct training intensity and rest period for the exercise test in equines. 相似文献
76.
Instructions on how to debone and stuff a turkey are available, but what is the best way to close it up? A randomised trial involving 15 turkeys was performed in order to evaluate skin disruption scores and cosmetic outcomes following the use of different suture patterns. Turkeys were deboned, stuffed and cooked according to guidelines of the US Department of Agriculture Food Safety and Inspection Services. After stuffing, they were randomly assigned to one of five closure groups: simple continuous Lembert; simple continuous Cushing; simple continuous Utrecht; simple continuous; or staples. Turkeys were cooked at 180 °C for two hours ensuring core temperature reached 75 °C. Suture line integrity was evaluated after removal of the sutures and the cosmetic aspect was graded. Before cooking, the Utrecht pattern and skin staples offered the best cosmetic result. After removal of the sutures, the skin remained intact only in the stapled group. All other suture patterns disrupted the skin after removal of the sutures, rendering the turkey less cosmetically appealing for serving. Closure of a stuffed turkey was best performed using skin staples to achieve the best cosmetic results. Using this technique you will be able to impress family and friends at a Christmas dinner, and finally show them your surgical skills. 相似文献
77.
A two-month-old female Tibetan terrier was re-presented with an incomplete closure of the patent ductus arteriosus. Following a second attempt to close the shunt by coil embolisation, arterial embolisation occurred. The successful removal of the embolised coil is described. 相似文献
78.
79.
Kovalik M Thoday KL Evans H van den Broek AH Mellanby RJ 《Veterinary journal (London, England : 1997)》2012,192(2):212-216
The aim of this study was to assess the effects of a standard therapeutic protocol of prednisolone (Pred) on glucose homeostasis in atopic dogs and compare it with previously published data for ciclosporin A (CsA). The central aim of the study was to assess and compare the effects of standard therapeutic protocols of prednisolone (Pred) and ciclosporin A (CsA) on glucose homeostasis in dogs with atopic dermatitis (CAD). Both treatments significantly reduced the physical signs of CAD, as determined by the canine atopic dermatitis extent and severity index version 3 (CADESI-03) and the Edinburgh Pruritus Scale (EPS). Post-treatment plasma glucose concentrations were not significantly different in the two groups, but serum insulin concentrations were significantly higher following Pred therapy (P<0.05). Serum fructosamine concentrations were not significantly different pre- and post-treatment with Pred, although previous studies had shown that CsA treatment increased fructosamine concentrations (P<0.005). The two treatment groups were recruited in a similar timeframe, were numerically matched and there were no differences in CADESI-03 and EPS scores between the CsA and Pred groups either before or after treatment. Thus, both CsA and Pred treatment were associated with mild disturbances in glucose metabolism, but only CsA therapy resulted in a significant increase in fructosamine concentrations. This information may be relevant to clinicians when considering therapeutic options for dogs with atopic dermatitis which already have impaired glucose homeostasis. 相似文献
80.
The effect of clenbuterol on the incidence of abomasal lesions in veal calves was studied in two fattening units. Some of the calves in each unit were treated with 1.6 micrograms clenbuterol/kg bodyweight/day from the seventh until the 23rd week of the fattening period. In one unit the calves were fed milk replacer only and 176 of the 236 calves were treated with clenbuterol. In the other unit the calves were fed roughage pellets in addition to milk replacer and 92 of the 194 calves were treated with clenbuterol. Only in the second unit did the calves treated with clenbuterol have significantly fewer abomasal lesions. 相似文献