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61.
This study was designed to investigate the impact of buserelin acetate (BA) or human chorionic gonadotropin (hCG) administration on the day of first artificial insemination (AI) on subsequent luteal profile (diameter of corpus luteum (CL) and plasma progesterone) and conception rate in Murrah buffalo. The present experiment was carried out at two locations in 117 buffalo that were oestrus‐synchronized using cloprostenol (500 μg) administered (i.m.) 11 days apart followed by AI during standing oestrus. Based on treatment (i.m.) at the time of AI, buffalo were randomly categorized (n = 39 in each group) into control (isotonic saline solution, 5 ml), dAI‐BA (buserelin acetate, 20 μg) and dAI‐hCG (hCG, 3000 IU) group. Out of these, 14 buffalo of each group were subjected to ovarian ultrasonography on the day of oestrus to monitor the preovulatory follicle and on days 5, 12, 16 and 21 post‐ovulation to monitor CL diameter. On the day of each sonography, jugular vein blood samples were collected for the estimation of progesterone concentrations. All the buffalo (n = 117) were confirmed for pregnancy on day 40 post‐ovulation. The conception rate was better (p < 0.05) in dAI‐BA (51.3%) and dAI‐hCG (66.7%) groups as compared to their control counterparts (30.8%). Furthermore, the buffalo of dAI‐hCG group had improved (p < 0.05) luteal profile, whereas the buffalo of dAI‐BA group failed (p > 0.05) to exhibit stimulatory impact of treatment on luteal profile when compared to control group. In brief, buserelin acetate or hCG treatment on the day of first AI leads to an increase in conception rate; however, an appreciable impact on post‐ovulation luteal profile was observed only in hCG‐treated Murrah buffalo.  相似文献   
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Several recent studies have indicated the important roles of Ser/Thr protein phosphatase1γ (PP1γ) in regulating the motility and capacitation of mammalian spermatozoa. Here, we report the presence and distribution of PP1γ protein in freshly ejaculated, in vitro capacitated and cryopreserved buffalo spermatozoa. The presence of PP1γ and its distribution were assessed by Western blotting and indirect immunofluorescence techniques, whereas the isoforms of PP1γ and their tyrosine phosphorylation status were identified by using 2D electrophoresis. The number of isoforms and the status of tyrosine phosphorylation of PP1γ were increased in capacitated spermatozoa when compared with freshly ejaculated spermatozoa. Differential pattern of expression and tyrosine phosphorylation of PP1γ were observed in cryopreserved spermatozoa, wherein some isoforms were degraded and some were tyrosine phosphorylated. In addition, immunofluorescence technique revealed that PP1γ was localized to principle, mid‐piece, post‐acrosomal and equatorial regions of buffalo spermatozoa. Differential distribution of tyrosine‐phosphorylated proteins were observed in fresh, capacitated and cryopreserved spermatozoa. The tyrosine phosphorylation of several proteins (20, 37, 38, 52, 60, 79 and 100 kDa) were increased when sperm cells were incubated with PP1γ inhibitor, okadaic acid. Together, our results suggest that buffalo spermatozoa express different isoforms of PP1γ protein. The protein expression and tyrosine phosphorylation of PP1γ were increased during capacitation. Furthermore, the differential pattern of expression and tyrosine phosphorylation of PP1γ were observed in cryopreserved spermatozoa. In addition, the inhibition of PP1γ protein increases protein tyrosine phosphorylation in capacitation.  相似文献   
64.
The ethics of animal-based research is a continuing area of debate, but ethical research protocols do not prevent scientific progress. In this paper, we argue that our current knowledge of the factors that affect reproductive processes provides researchers with a solid foundation upon which they can conduct more ethical research and simultaneously produce data of higher quality. We support this argument by showing how a deep understanding of the genetics, nutrition and temperament of our experimental animals can improve compliance with two of the '3 Rs', reduction and refinement, simply by offering better control over the variance in our experimental model. The outcome is a better experimental design, on both ethical and scientific grounds.  相似文献   
65.
The effects of translucent polyethylene sheeting as a thermal covering to eradicate Pueraria montana (kudzu) were investigated at Clemson, South Carolina on a clay loam. In 2005, the highest reduction of live root crowns was observed where P. montana was covered for the entire growing season (May–October) with a reduction of 42% of live root crowns compared with the control plots. Where P. montana was covered for alternate weeks throughout the growing season live root crowns were reduced by 35%. Covering P. montana for one week and then uncovering for four weeks repeatedly through the season killed 24% of root crowns. In 2006, the second year of treatment to the same plots, the three solarization treatments had similar efficacy of about 97%. The use of polyethylene sheeting appears not to be cost‐effective for general control of large P. montana infestations, but may be useful for small patches.  相似文献   
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67.
1. A total of 144 chickens purchased from peasants in Morogoro, Tanzania were slaughtered, their crops dissected and the contents analysed. The birds consisted of 48 chickens from each of three climatic zones (warm and wet, warm and dry, cool and wet). Seventy-two chickens were slaughtered in each season, that is short rainy and long rainy season. 2. Cereal grains, bran, green forages, insects/worms and kitchen food wastes were the main crop contents and their composition varied significantly with season and climate. 3. The overall mean chemical compositions (g/kg) of the crop contents were: 430.8 +/- 107.78 dry matter (DM), 104.4 +/- 43.47 crude protein (CP), 61.2 +/- 36.48 ether extract (EE), 58.2 +/- 26.29 crude fibre (CF), 125.4 +/- 58-27 ash, 6.3 +/- 5.19 calcium (Ca) and 3.6 +/- 2.41 phosphorus (P). 4. CP, EE, ash and P contents varied significantly (P<0.05) with season but contents of DM, CF and Ca were not significantly different. 5. CP content was significantly higher (P<0.05) in growers than in adults while the reverse was true for Ca content. Other variables did not differ significantly. 6. Significant differences (P<0.05) in chemical composition were observed among the zones in all parameters except for CP content. 7. The study showed that the chemical composition of feeds eaten by rural scavenging chickens was below the nutritional requirements and varied with season, climate and age of birds.  相似文献   
68.
不同种植密度和施肥水平对大豆籽粒品质的影响   总被引:12,自引:0,他引:12  
本试验自2002年开始至2004年止,从种植密度和施肥水平两方面对大豆脂肪、蛋白质含量的影响进行了分析。结果表明:种植密度对大豆籽粒的脂肪、蛋白质含量具有显著的影响,相关性分析结果显示,种植密度与大豆籽粒的脂肪含量存在着负相关性,与籽粒中的蛋白质含量之间为正相关。中国品种的脂肪含量受种植密度的影响大于美国品种,而中国品种的蛋白质含量受种植密度的影响小于美国品种。蛋脂总含量受种植密度的影响较小,并且不存在品种间的差异性。磷酸二铵的施用量与大豆籽粒脂肪含量和蛋白质含量之间没有显著的相关性,但是中美品种的品质对磷酸二铵施用量的反应不同。磷酸二铵的施用量与中国品种的脂肪含量、蛋白质含量和蛋脂总含量呈正相关,而与美国品种的脂肪、蛋白质含量和蛋脂总含量呈负相关,但相关程度均不显著。  相似文献   
69.
The variation in the kidding size of Black Bengal and Sirohi breed of goats makes them an interesting genetic material to study the underlying genetic mechanism of prolificacy. Accordingly, we studied the comparative ovarian morphometry including disparity in numbers of antral follicles of different sizes between these two breeds. Further, we evaluated the differential expression of the important candidate genes (viz., BMP15, GDF9 and BMPR1B) known to influence the ovulation rates and the prolificacy. The ovaries of Black Bengal (n = 20) goat were lighter (p < 0.01) in weight and smaller (p < 0.01) in diameter than those of Sirohi (n = 19) goats but possessed more numbers (p < 0.05) of corpus luteum (CL), large and small antral follicles. Quantitative real‐time PCR (RT‐qPCR) analysis revealed differential expression of mRNAs encoding for the BMP15 and GDF9. Small antral follicles of Black Bengal goats expressed 2.78‐fold more (p < 0.05) of BMP 15 than those of Sirohi goat. Expression of BMP15 (p < 0.01) and GDF9 (p < 0.05) mRNAs was more abundant in the small than the large antral follicles of Black Bengal goat. The more numbers of antral follicles per unit of ovarian mass and differential expression of BMP15 and GDF9 may serve as an important clue for higher prolificacy.  相似文献   
70.
PDC‐109, one of the most abundant proteins in bovine seminal plasma, has detrimental effect on spermatozoa in a time‐ and concentration‐dependent manner. Therefore, we hypothesized that sequestration of detrimental protein from ejaculates would be beneficial following cryopreservation of sperm cells. To this aim, we evaluated the effect of sequestration of PDC‐109 either by anti‐PDC‐109 antibodies (Ab) or egg yolk (EY) alone or by the synergistic action of EY + Ab in minimizing cryoinjury to bull spermatozoa. PDC‐109 protein was purified by applying two‐step chromatography procedures. The purified protein was injected in rabbits to raise antibodies which were isolated using ion‐exchange chromatography. After checking the Ab cross‐reactivity, they were quantitated and added to ejaculates, either alone or in addition to EY in Tris‐glycerol (TG) extender. Thus, ejaculates were processed in extender containing EY + TG (group I), Ab + TG (group II) or EY + Ab + TG (group III). Semen quality parameters (SQPs) viz. viability and acrosome integrity (FITC‐PSA), cryoinjury to spermatozoa (chlortetracycline, CTC assay) and in vitro fertility of protein‐sequestered‐semen (zona‐penetration assay) were evaluated. A significant (p < 0.05) improvement in post‐thaw SQPs as well as in non‐capacitated spermatozoa observed at pre‐freeze and post‐thaw stages of cryopreservation in group III compared with other groups indicated reduction in protein‐mediated cryoinjury. From this study, it can be concluded that sequestration of PDC‐109 by synergistic action of EY+Ab as compared to either of them alone significantly improve sperm quality and minimize cryoinjury to bull spermatozoa upon storage at ultra‐low temperatures.  相似文献   
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