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1.
At the time of AI following Ovsynch protocol, a total of 51 buffaloes were randomly divided in a first group (n = 30) subjected to conventional AI into the uterine body with 20 million non-sex sorted frozen-thawed spermatozoa, while a second group (n = 21) was inseminated near the utero-tubal junction (UTJ) ipsilateral to the ovary carrying the preovulatory follicle with 2.5 million live (4 million total) sex-sorted frozen-thawed spermatozoa. The semen used for flowcytometric sorting was collected and processed on a farm in Italy, and then shipped to a laboratory in Germany. Eleven buffaloes were inseminated with X-chromosome bearing spermatozoa and 10 with Y-chromosome bearing spermatozoa. Conception rates after conventional and UTJ inseminations were 43.3% (n = 13) and 42.8% (n = 9) respectively (p = 0.97). Eight of the nine foetuses obtained after insemination with sexed spermatozoa corresponded to the sex as predicted by the cell sorting procedure (five male and four female foetuses by ultrasound vs six male and three female foetuses by cell sorting). In conclusion, for the first time buffalo semen has been successfully subjected to procedures for flowcytometric sperm sorting and freezing. Low doses of sexed spermatozoa have been deposited near the UTJ giving conception rates similar to those of conventional AI with full dose.  相似文献   
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OBJECTIVE: To determine whether dorsal loading of the pelvis and type of chemical restraint affected the dorsolateral subluxation (DLS) score of dog hips. STYDY DESIGN: In vivo testing of diagnostic method. ANIMALS: Labrador retrievers, Greyhounds, and crosses between both breeds (n = 119 dogs). METHODS: Dorsal load was applied to the hips through a strap that was placed over the hips, and the peak vertical and steady-state vertical, ground-reaction forces exerted on the stifles were measured in the DLS position. The DLS score was measured with their hips under dorsal load and compared with the DLS score without load. For 24 dogs, the DLS score was measured both under chemical restraint (medetomidine) and under general anesthesia. Wilcoxon-signed rank test and paired t test was used to compare effects of dorsal load and restraint method on the left and right DLS hip score, and P <.05 was considered significant. RESULTS: Both stifles together accepted median 15% body weight in the vertical plane in the unloaded steady state. Loading the hips increased the steady-state, vertical ground-reaction force to 34% body weight. At 8 months of age, loading significantly decreased the DLS score from 65% +/- 11% (mean +/- SD) to 60% +/- 12% for left hips and 66% +/- 11% to 63% +/- 13% for right hips. The left hip DLS score was affected by load more consistently than the right hip. In general, loading the hips decreased the DLS score in all breeds by 4% to 6% except for the greyhounds, in which the DLS score was unchanged by dorsal loading. When grouped by their DLS scores, load significantly decreased DLS scores in dogs with unloaded scores greater than 55% (nondysplastic), whereas DLS scores of dogs with unloaded scores between 55% and 45% (dysplastic) and less than 45% did not change significantly with load. Unloaded scores did not change significantly when compared under sedation versus general anesthesia. However, load significantly decreased the DLS score under general anesthesia for the left hip but not for the right hip. CONCLUSIONS: Less than half of the vertical ground-reaction force normally exerted by the hindlegs of a standing dog was sufficient to induce hip subluxation in the DLS position. Although dorsal loading approximately doubled the steady-state, vertical ground-reaction force, the decrease in the DLS score under load was never greater than 6%. Furthermore, the DLS scores of dogs most likely to be dysplastic (based on DLS scores <45%) were not affected by load, whereas load slightly decreased DLS cores of dogs with DLS scores greater than 55%. CLINICAL RELEVANCE: External influences can change the DLS score significantly, but the magnitude of change is unlikely to be of clinical importance, making the method useful as a field screening test for both dysplastic and nondysplastic hips in young dogs.  相似文献   
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REASONS FOR PERFORMING STUDY: Contributes to the understanding of the pathogenesis of dorsal displacement of the soft palate during exercise so that management of this condition could be enhanced. HYPOTHESIS: That the thyrohyoid muscles play an important role in the stability of the laryngo-palatal relationship and that dysfunction of these muscles leads to dorsal displacement of the soft palate (DDSP) during exercise. METHODS: Ten horses were exercised on a high-speed treadmill under 4 different treatment conditions: control conditions (n = 10), after resection of thyrohyoid muscles (TH, n = 10), after sham-treatment (n = 5), or after restoration of function of the thyrohyoid muscles with surgical sutures (prosthesis-treatment, n = 6). During trials, the following determinations were made: videoendoscopy of the upper airway, gait frequency and pharyngeal and tracheal static pressures. RESULTS: None of the 10 horses developed DDSP during 2 separate treadmill-exercise trials under the control conditions. Seven of the 10 horses developed DDSP after resection of the TH muscles, 4 of 5 of these horses still experienced DDSP after sham-treatment, but 5 of 6 horses no longer experienced DDSP at exercise after the prosthesis-treatment. There were significant anomalies in airway pressures, respiratory frequency, and occurrence of DDSP in both the TH resection and sham-treatment conditions compared to control conditions. In contrast, no statistical differences were noted in any of the parameters measured between the prosthesis-treatment and control conditions. CONCLUSIONS: That the function of the TH muscles is important to the stability of the laryngo-palatal relationship and plays a role in the pathophysiology of exercise-induced DDSP. POTENTIAL RELEVANCE: Management of horses with DDSP could be enhanced by restoring the function of the TH muscles.  相似文献   
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The objectives of this work were to determine the changes in the expression of neuroendocrine markers in Leydig cell by oestradiol treatment, and to determine whether testosterone is able to recover partially the effects of hormonal suppression induced by oestradiol. Adult male rats were injected daily with either 50 microg of oestradiol or oestradiol plus testosterone propionate (25 mg every 3 days) for 15 days. The animals were sacrificed and testicles were dissected and processed by routine histological protocols. FSH and LH serum levels were determined by radioimmunoassay. The visualization of antigens was achieved by the streptavidin-peroxidase immunohistochemical method. Antibodies against chromogranin A (CrA), S-100 protein (S-100), P substance (PS), synaptofisin (SYN), neurofilament protein (NF), gliofibrillary acidic protein (GFAP) and neuron specific enolase (NSE) were used. The mean LH and FSH serum concentrations were consistently suppressed with hormonal treatments. Intermediate filaments (NF and GFAP) showed no difference in their expression. The expression of S-100, NSE and SYN was significantly lower in both hormone-treated groups. In oestradiol-treated rats, the immunoreactivity of CrA and SP decreased significantly but was restored after testosterone supplementation. Although the nature and functions of many of these substances in Leydig cells remain unknown, these results are consistent with the hypothesis that the expression of some neuroendocrine markers is hormonally controlled.  相似文献   
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Haemoglobinuria and periumbilical discoloration (also known as Cullen's sign) are clinical signs uncommonly reported in veterinary patients. This report describes a case of retroperitoneal haemorrhage in a dog, associated with haemoglobinuria and Cullen's sign. To the authors' knowledge, these clinical signs have not previously been reported singularly or in combination with retroperitoneal haemorrhage in dogs. A neutered male Shetland sheepdog, which was presented for haematuria, also had an abdominal mass, abdominal pain and a large area of periumbilical discoloration. Laboratory studies determined that haemoglobinuria was the cause of the red-coloured urine. Abdominal radiographs suggested a splenic mass and a coeliotomy was performed. During the induction and throughout the anaesthetic period the dog was hypertensive and a large haematoma originating from the right retroperitoneal space was identified at surgery. The cause of the haemorrhage was uncertain but a ruptured phaeochromocytoma was thought possible on the basis of the persistent hypertension and the location of the haemorrhage.  相似文献   
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We describe 4 young male Doberman Pinschers (3 littermates and 1 unrelated dog) with a syndrome resembling idiopathic or noncirrhotic portal hypertension of humans. Each dog was evaluated for a hepatopathy resulting in portal hypertension, development of portosystemic collateral vessels, and hepatic encephalopathy. These dogs differ from previous reports of young dogs with hepatic insufficiency associated with portal hypertension and acquired portal systemic shunting by their lack of intrahepatic arteriovenous fistulae, portal vein atresia, or intrahepatic fibrosis. Clinicopathologic features included erythrocyte microcytosis, normal to mildly increased liver enzyme activities, increased concentrations of serum bile acids, reduced plasma indocyanine green clearance, and normal total bilirubin concentration. Abdominal ultrasonography disclosed a small liver and portosystemic collateral vessels. Radiographic imaging studies confirmed hepatofugal portal circulation and discounted hepatic arteriovenous fistulae. Histopathologic features in liver tissue from each dog were similar and consistent in all sections examined. Common findings included increased cross-sectional views of hepatic arterioles; hepatic lobular atrophy; scanty increase in connective tissue around some large portal triads; and absence of inflammation, disturbed lobular architecture, bile duct proliferation, or intrahepatic cholestasis.  相似文献   
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Previous investigations have suggested waxy (amylose‐free) wheats (Triticum aestivum L.) possess weak gluten properties and may not be suitable for commercial gluten extraction. This limitation could prevent the use of waxy wheat as a source of unique starch, because gluten is a by‐product of the wheat starch purification process. Fifty waxy wheat lines were used to determine the extent to which gluten protein and other grain quality related traits might vary and, consequently, allow the development of waxy wheat with acceptable gluten properties. Among the waxy lines, significant variation was observed for all measured quality traits with the exception of flour protein concentration. No waxy entries statistically equaled the highest ranking nonwaxy entry for grain volume weight, falling number, flour yield, or mixograph mix time. No waxy lines numerically exceeded or equaled the mean of the nonwaxy controls for falling number, flour yield, or mixograph mix time. For grain and flour protein related variables, however, many waxy lines were identified well within the range of acceptability, relative to the nonwaxy controls used in this study. Approximately 50% of the waxy lines did not differ from the highest ranking nonwaxy cultivar for grain and flour protein concentrations. Forty‐three (86%) of the tested waxy lines were not sig‐nificantly different from the nonwaxy line with the highest mixograph mixing tolerance, 22/50 (44%) of the waxy wheat lines did not differ from the highest ranking nonwaxy line in gluten index scores, and 17/50 (34%) did not differ from the highest ranking nonwaxy line in extracted wet gluten. All waxy experimental lines produced gluten via Glutomatic washing. The quality of the gluten, as measured both by mixograph and gluten index, varied widely among the waxy lines tested. These observations suggest that weak gluten is not a natural consequence of the waxy trait, and waxy cultivars with acceptable gluten properties can be developed.  相似文献   
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The aim of this work was to evaluate the effect of relaxin on fertility parameters of buffalo frozen/thawed sperm. Sperm were incubated in the absence of capacitating agents (negative control), with a known capacitating agent such as heparin (positive control) and with 50 and 100 ng/ml relaxin for 2 and 4 h. Sperm viability, motility, capacitation and the effect of relaxin on the fertilizing ability after heterologous IVF were evaluated. Although viability was not affected, relaxin increased (p < 0.05) sperm motility compared to the negative and positive controls both after 2 h (60.0 ± 2.0, 60.0 ± 3.1, 68.3 ± 1.7 and 69.4 ± 2.7, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) and 4 h (55.0 ± 2.5, 53.3 ± 3.0, 62.2 ± 3.0 and 65.0 ± 3.2, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) incubation. When sperm were incubated with both 100 ng/ml relaxin and heparin, a decrease (p < 0.01) of pattern A, that is low capacitation level, was observed compared to the negative control both after 2 h (54.4, 34.3 and 36.4%, respectively, in negative control, positive control and 100 ng/ml relaxin) and 4 h (51.9, 35.0 and 34.3%, respectively, in negative control, positive control and 100 ng/ml relaxin). Moreover, an increase (p < 0.01) of pattern EA, that is high capacitation level, was recorded with 100 ng/ml relaxin and heparin compared to the negative control both after 2 h (44.1, 59.3 and 57.7%, respectively, in negative control, positive control and 100 ng/ml relaxin) and after 4 h (43.0, 54.4 and 56.0%, respectively, in negative control, positive control and 100 ng/ml relaxin). Finally, relaxin increased (p < 0.01) cleavage rate compared to the negative control (57.1 ± 4.4, 72.5 ± 6.0, 71.4 ± 5.5 and 73.6 ± 2.9, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin). In conclusion, relaxin has a beneficial effect on motility, capacitation and fertilizing ability of frozen–thawed buffalo sperm.  相似文献   
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