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111.
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   
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Antioxidative activities of the extracts from Sargassum siliquastrum were determined using the inhibition of red blood cell (RBC) hemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) radicals, suppression of lipid peroxidation using rat brain homogenate, and scavenging activity of superoxide radicals. The dichloromethane fraction isolated from the methanol crude extract by differential solvent extractions exhibited the strongest antioxidant activity in both RBC hemolysis and lipid peroxidation assays. This fraction was further fractionated into four subfractions F1-F4 by silica gel column chromatography. F1 was found to be most effective in protecting RBC against AAPH radicals and in inhibiting lipid peroxidation. On the basis of thin-layer chromatography and UV and IR spectra analyses, all subfractions contained phenolic compounds. However, there was no correlation between the above antioxidant potency and total phenolic compounds estimated by using the Folin-Ciocalteau method.  相似文献   
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Genetic diversity in 90 Indian soybean cultivars was assessed using 45 SSR markers distributed on 20 soybean chromosomes. Forty-five SSR markers generated 232 alleles with an average of five alleles/locus. The observed frequencies of the 232 alleles ranged from 0.01 to 0.94 with an average of 0.19. The polymorphic information content (PIC) value of the SSR markers varied from 0.10 to 0.83 with an average of 0.61 and about 71% markers have a PIC value of >0.5. In this study, 54 rare alleles including 19 genotype specific alleles were also identified. The observed hetrozygosity for SSR markers ranged from 0 to 0.11 with a mean of 0.10. Cluster analysis grouped the 90 soybean cultivars into three major clusters and principal coordinates analysis (PCoA) results were similar to those of the cluster analysis. A combination of eight SSR markers successfully differentiated all 90 soybean cultivars. The population structure analysis distributed the 90 soybean genotypes into two populations with mean alpha (α) value of 0.1873. In AMOVA analysis, proportion of variation within population was high (88%), whereas only 12% occurred among populations. In cluster and structure analyses, most of the genotypes with similar pedigree were grouped together. Soybean cultivars DS228, MACS-13, LSb-1, Hardee, Improved Pelican, and Pusa-24 were the six most genetically distinct cultivars identified. The study reported a moderate genetic diversity in Indian soybean cultivars and findings would be useful to the soybean breeders in selecting genetically distinct parents for a soybean improvement program.  相似文献   
116.
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   
117.
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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Nine rats (16.4%) out of 55 (Rattus norvegicus) from cattle farms were seropositive to Neospora caninum. Two of the seropositive rats were also PCR positive but all were negative by immunohistochemistry and PAS staining. The brains of all the captured rats were homogenized and initially inoculated intraperitoneally into nude mice or into SPF ICR mice, which had been immunosuppressed with prednisolone. One mouse that was inoculated with brain material from a seropositive rat became infected with N. caninum, as demonstrated by the presence of a tissue cyst in the brain and confirmed by immunohistochemistry and PCR. This is the first finding of N. caninum in naturally infected farm rats. The findings show that natural N. caninum infection occurs in wild brown rats and thus rats may serve as a reservoir for the protozoan on the cattle farm.  相似文献   
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