Testing Usability of Butylated Hydroxytoluene in Conservation of Goat Semen     

TAA Khalifa  AG Lymberopoulos  BE El‐Saidy 《Reproduction in domestic animals》2008,43(5):525-530

The objective of this study was to investigate whether butylated hydroxytoluene (BHT) could be used as a suitable supporter or alternative of egg yolk during preservation of goat spermatozoa. Three in vitro experiments and a fertility test were conducted to evaluate the effect of BHT on viability of chilled‐stored semen as well as motility and kidding rate of frozen‐thawed spermatozoa. In the first two experiments, ejaculates (n = 30/experiment) were collected from 10 bucks, split, diluted with egg yolk‐based and egg yolk‐free extenders supplemented with or without 0.3, 0.6, 2, 5 and 8 mm BHT and stored at 5°C for 168 h. In the third experiment, 30 ejaculates were collected from the above‐mentioned bucks, split and diluted with egg yolk‐free extenders supplemented with or without 0.3, 0.6 and 0.9 mm BHT and egg yolk‐based extenders supplemented with or without 5 mm BHT. Diluted semen was cooled to 5°C over a period of 4 h, frozen and thawed in the form of 0.3‐ml pellets. In the fertility test, 75 ejaculates were collected from two proven fertile bucks, split, diluted with egg yolk‐free extenders containing 0.6 mm BHT and egg yolk‐based extenders supplemented with or without 5 mm BHT, frozen and thawed as described above. An insemination volume of 0.6 ml containing 120–140 × 10⁶ progressively motile spermatozoa was used for a single cervical insemination of cloprostenol‐synchronized does (n = 230). The results showed that addition of 5 mm BHT to egg yolk‐deficient (2.5%) extenders significantly improved viability of chilled‐stored semen together with motility (48.5%) and fertility (62.5%) of frozen‐thawed spermatozoa. Replacement of egg yolk in semen extenders by 0.6 mm BHT could sustain not only viability of chilled‐stored semen but also post‐thaw motility (47.5%) and fertility (53.75%) of frozen‐thawed spermatozoa. In conclusion, supplementation of semen diluents with BHT can ameliorate preservability of goat sperm.  相似文献   

In vitro Effect of Zearalenone and α-Zearalenol on Boar Sperm Characteristics and Acrosome Reaction   总被引：2，自引：0，他引：2  

IA Tsakmakidis  AG Lymberopoulos  C Alexopoulos  CM Boscos  SC Kyriakis 《Reproduction in domestic animals》2006,41(5):394-401

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   

The Current State of Solar Modeling     

J Christensen-Dalsgaard  W Dappen  SV Ajukov  ER Anderson  HM Antia  S Basu  VA Baturin  G Berthomieu  B Chaboyer  SM Chitre  AN Cox  P Demarque  J Donatowicz  WA Dziembowski  M Gabriel  DO Gough  DB Guenther  JA Guzik  JW Harvey  F Hill  G Houdek  CA Iglesias  AG Kosovichev  JW Leibacher  P Morel  CR Proffitt  J Provost  J Reiter  EJ Rhodes  FJ Rogers  IW Roxburgh  MJ Thompson  RK Ulrich 《Science (New York, N.Y.)》1996,272(5266):1286-1292

Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations.  相似文献   

Does Clinical Treatment with Phenylbutazone and Meloxicam in the Pre‐ovulatory Period Influence the Ovulation Rate in Mares?          下载免费PDF全文

AG Lima  LCB Costa  MA Alvarenga  CB Martins 《Reproduction in domestic animals》2015,50(5):771-775

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   

The Seismic Structure of the Sun     

DO Gough  AG Kosovichev  J Toomre  E Anderson  HM Antia  S Basu  B Chaboyer  SM Chitre  J Christensen-Dalsgaard  WA Dziembowski  A Eff-Darwich  JR Elliott  PM Giles  PR Goode  JA Guzik  JW Harvey  F Hill  JW Leibacher  MJPFG Monteiro  O Richard  T Sekii  H Shibahashi  M Takata  MJ Thompson  S Vauclair  SV Vorontsov 《Science (New York, N.Y.)》1996,272(5266):1296-1300

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   

Transgenic Cry1Ac + CpTI cotton does not compromise parasitoid-mediated biological control: An eight-year case study     

Fan Yang  Bing Liu  Yulin Zhu  Nicolas Desneux  Lituo Liu  Caihong Li  Kris AG Wyckhuys  Yanhui Lu 《Pest management science》2022,78(1):240-245

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Causes of perinatal deaths in foals in New Zealand in the 2007 and 2008 seasons     

AG Wolfe  AC Johnstone  IG Mayhew 《New Zealand veterinary journal》2013,61(1)

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Sperm Chromatin Stability During In Vitro Manipulation of Beef Bull Semen     

AG Lymberopoulos  TAA Khalifa 《Reproduction in domestic animals》2010,45(2):307-314

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   

Neuroaxonal dystrophy in Merino sheep     

PAW HARPER  AG MORTON † 《Australian veterinary journal》1991,68(4):152-153

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A primary extraskeletal osteogenic sarcoma arising in the spleen of a dog     

AG. JABARA  JB. McLEOD† 《Australian veterinary journal》1989,66(1):27-29

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