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This study was conducted to determine the in vitro effects of three different concentrations (125, 187.5 and 250 microM in diluted semen) of zearalenone (zen) and alpha-zearalenol (alpha-zen) on boar sperm. Semen parameters such as motility, viability and spontaneous acrosome reaction were evaluated. From the results it was shown that both zen and alpha-zen affected the sperm characteristics significantly (p < 0.05), except for alpha-zen at the low concentration which did not decrease the percentage of live reacted spermatozoa significantly. In conclusion, zen and alpha-zen are directly toxic when they affect boar semen in vitro and consequently decrease the fertilization ability of the sperm. The higher the concentration of mycotoxin tested, the greater the decline of sperm parameters noticed. The influence of mycotoxins was found to be time- and dose-dependent.  相似文献   
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The presence of anovulatory haemorrhagic follicles during the oestrous cycle of mares causes financial impacts, slowing conception and increasing the number of services per pregnancy. Non‐steroidal anti‐inflammatory drugs (NSAIDs) such as meloxicam and phenylbutazone are used in the treatment of several disorders in mares, and these drugs can impair the formation of prostaglandins (PGs) and consequently interfere with reproductive activity. This study aimed to evaluate the effects of treatment with NSAIDs on the development of pre‐ovulatory follicles in mares. In total, 11 mares were studied over three consecutive oestrous cycles, and gynaecological and ultrasound examinations were performed every 12 h. When 32‐mm‐diameter follicles were detected, 1 mg of deslorelin was administered to induce ovulation. The first cycle was used as a control, and the mares received only a dose of deslorelin. In the subsequent cycles, in addition to receiving the same dose of deslorelin, each mare was treated with NSAIDs. In the second cycle, 4.4 mg/kg of phenylbutazone was administered, and in the third cycle, 0.6 mg/kg of meloxicam was administered once a day until ovulation or the beginning of follicular haemorrhage. All of the mares ovulated between 36 and 48 h after the induction in the control cycle. In the meloxicam cycle, 10 mares (92%) did not ovulate, while in the phenylbutazone cycle, nine mares (83%) did not ovulate. In both treatments, intrafollicular hyperechoic spots indicative of haemorrhagic follicles were observed on ultrasound. Thus, our results suggested that treatment with meloxicam and phenylbutazone at therapeutic doses induced intrafollicular haemorrhage and luteinization of anovulatory follicles.  相似文献   
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Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However, immediately beneath the convection zone and at the edge of the energy-generating core, the sound-speed variation is somewhat smoother in the sun than it is in the model. This could be a consequence of chemical inhomogeneity that is too severe in the model, perhaps owing to inaccurate modeling of gravitational settling or to neglected macroscopic motion that may be present in the sun. Accurate knowledge of the sun's structure enables inferences to be made about the physics that controls the sun; for example, through the opacity, the equation of state, or wave motion. Those inferences can then be used elsewhere in astrophysics.  相似文献   
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Seven experiments were conducted to study the effect of freezing extenders, antioxidants, motility stimulants, thawing temperature, incubation temperature and time, centrifugation and capacitation on sperm chromatin instability (CI) as well as the influence of sperm CI on pregnancy rates of heifers (n = 360) after AI with frozen semen. Semen was collected once a week from Blonde d’Aquitaine and Limousine bulls (n = 3/breed) via an artificial vagina and only individual ejaculates (n = 300) of >0.3 × 109 sperm/ml and ≥ 70% progressive motility were used. Sperm CI was evaluated by nuclear DNA susceptibility to acid‐induced denaturation using acridine orange fluorescence and by chromatin susceptibility to decondensation using quantitative transmission electron microscopy. Bioxcell extender was better than AndroMed and egg yolk extenders in terms of low incidence of sperm CI in one bull (p < 0.05). Neither antioxidants (EDTA–2Na, Na‐pyruvate and albumin) nor motility stimulants (caffeine and blood serum) had any significant effect on sperm CI. Thawing of frozen semen at 45°C for 30 s decreased (p < 0.025) CI in one bull. Incubation of frozen sperm at 25 and 39°C for 240 min increased sperm CI percentages from 3.47 ± 0.48 and 4.50 ± 0.41% to 6.70 ± 0.36 and 9.71 ± 0.53%, respectively (p < 0.001). Although centrifugation and removal of extracellular milieu increased CI of cooled sperm, it decreased CI of frozen–thawed sperm (p < 0.025). Follicular fluid as a capacitating agent destabilized chromatin structure (p < 0.001). Sperm vulnerability to CI had a negative impact (r2 = 0.37–0.77, p < 0.001) on fertility of frozen ejaculates. In conclusion, in vitro manipulation of bovine semen can influence incidence of sperm CI, whereas integrity of sperm chromatin contributes significantly to heifers’ fertility. We would recommend selection of the appropriate extender and thawing temperature for each bull together with careful manipulation of frozen semen to minimize damage of sperm chromatin.  相似文献   
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This paper describes a primary extraskeletal osteogenic sarcoma arising in the spleen of an 11-year-old, male, cross-bred Terrier. Initial diagnosis was made after surgical removal of a splenic mass, at which time the liver and other abdominal viscera appeared grossly normal. However, elevations in the activities of alanine aminotransferase and alkaline phosphatase in blood taken 7 days after laparotomy suggested that hepatic metastases were developing. This was confirmed when the dog died 3.5 months after surgery, with massive hepatic metastatic involvement. There appears to be no previous report of the spleen being the primary site of such a neoplasm in the dog.  相似文献   
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Lupinosis was produced in sheep in four experiments by administering a toxic extract of Phomopsis leptostromiformis by various routes and at various dose rates. The course of the intoxication was followed by plasma biochemical analyses for a number of electrolytes, metabolites and enzymes. Results from these analyses suggested that in addition to being an hepatotoxicity, lupinosis also resulted in injury to muscle, kidney and adrenal cortex. This was confirmed by microscopic examination of these tissues.  相似文献   
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