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排序方式: 共有247条查询结果,搜索用时 15 毫秒
151.
T Anand D Kumar MK Singh RA Shah MS Chauhan RS Manik SK Singla P Palta 《Reproduction in domestic animals》2011,46(1):50-58
In this study, inner cell mass (ICM) cells were isolated from in vitro produced buffalo blastocysts and were cultured on mitomycin‐C treated buffalo foetal fibroblast feeder layer for producing embryonic stem (ES) cells. Among different sources (hatched vs expanded blastocysts) or methods (enzymatic vs mechanical), mechanical isolation of ICM from hatched blastocysts resulted in the highest primary colony formation rate and the maximum passage number up to which ES cells survived. Putative ES cells expressed alkaline phosphatase and exhibited a normal karyotype up to passage 7. Putative ES cells and embryos at 2‐ to 4‐cell, 8‐ to 16‐cell, morula and blastocyst stages strongly expressed stage‐specific embryonic antigen (SSEA)‐4 but lacked expressions of SSEA‐1 and SSEA‐3. Putative ES cells also expressed tumour rejection antigen (TRA)‐1‐60, TRA‐1‐81 and Oct4. Whereas in all early embryonic stages, TRA‐1‐60 was observed only in the periplasmic space, and TRA‐1‐81 expression was observed as small spots at a few places inside the embryos, both these markers were expressed by ICM. Oct4 expression, which was observed at all the embryonic stages and also in the trophectoderm, was the strongest in the ICM. Buffalo putative ES cells possess a unique pluripotency‐related surface antigen phenotype, which resembles that of the ICM. 相似文献
152.
The present study investigated the genetic component of host resistance to gastrointestinal nematode infections in two goat breeds in a semi-arid climatic region of India. The study was carried out on 888 animals belonging to two goat breeds. Live weight, faecal egg counts (FEC) and packed cell volume (PCV) following natural parasite challenge were measured at 3, 6, 9 and 12 months of age over a 3-year period. Pedigree relationships between goats extending back 3 generations were available. The study estimated the heritabilities of indicator traits (FEC and PCV) in goats and also quantified relationships between indicator traits and growth traits at the genetic, phenotypic and environmental level. It also provided an insight for the inclusion of genetic information on resistance to nematode infection into breeding programmes. The heritabilities of the indicator traits were low to moderate in this population. Genetic correlations between FEC at 6, 9 and 12 months of age were strong (approaching unity) indicating that the trait may be controlled by same genes at these different ages. The genetic correlation between FEC and PCV from 6 months of age onwards was negative and moderate to strong. Correlations between FEC and growth traits tended to be negative. Selection index modeling investigated the use of FEC, PCV and bodyweight in selection schemes. Selection based on the measurements at 9 months of age was proposed as a means of improving productivity as well as reducing pasture contamination, thereby enhancing sustainable livestock production. 相似文献
153.
J. S. Chauhan M. K. Tyagi A. Kumar N. I. Nashaat M. Singh N. B. Singh M. L. Jakhar S. J. Welham 《Plant Breeding》2007,126(4):399-402
Effects of drought on yield and yield components were investigated during the spring season 2000–2001 by growing 14 Indian mustard genotypes under irrigated and rain-fed conditions at Bharatpur and Jobner. A disease and pest management schedule was followed when required. The drought susceptibility index (DSI) for seed yield and component characteristics was calculated to characterize the relative tolerance of genotypes. Plant height, primary branches, secondary branches per plant, 1000-seed weight and seed yield were reduced under rain-fed conditions. The top five genotypes at Bharatpur that showed tolerance to moisture stress for seed yield, as indicated by their lowest DSI, were, in descending order PSR-20, PRO-97024, JMMWR-941, IS-1787 and PCR-7, whereas at Jobner these were JMMWR-941, RC-1446, PSR-20, RH-819 and 'Varuna'. Of these, PSR-20 and JMMWR-941 were among the top six at both locations. These genotypes also showed relatively low DSI for one or more characteristics, such as primary branches per plant, secondary branches per plant, harvest index and seed : husk ratio. Genotypes with the lowest DSI, particularly for seed yield at both locations, would serve as useful donors in the breeding programme for improving the drought tolerance of existing Indian mustard cultivars. 相似文献
154.
Reactions of Hordeum chilense accessions H1 and H7 and their amphiploids, HT8, HT9 and HT28 (named as tritordeum) alongwith
wheat lines, T22, T24 and T59 used in their synthesis, were studied for resistance to the Karnal bunt pathogen (Tilletia indica)
of wheat. Both the accessions of H. chilense and one tritordeum line, HT8, were rated as highly resistant with zero co-efficient
of infection, whereas the other two tritordeum lines HT28 and HT9 were rated as moderately susceptible and susceptible with
5.2 and 10.5 co-efficients of infection, respectively, compared to reaction of the wheat lines involved in their synthesis.
Karnal bunt infection was maximum on the susceptible wheat cultivar WL-711 with 24.3 co-efficient of infection. All the wheat
lines involved in the synthesis of amphiploids were susceptible to Karnal bunt except, T59 (Triticum sphaerococcum) (6X),
which showed a moderate level of resistance.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
155.
F Sánchez‐Dávila RA Ledezma‐Torres G Padilla‐Rivas AS del Bosque‐González A González Gómez H Bernal‐Barragán 《Reproduction in domestic animals》2014,49(4):e40-e43
The aim of this research was to evaluate the effectiveness of three pFSH doses (80 mg; 145 mg and 215 mg) on ovarian response and on quantity and quality of transferable embryos of goats during the breeding and the non‐breeding seasons. Ovary structures were exposed (laparatomy under general anaesthesia) and numbers of follicles and corpora lutea were registered. Surgical embryo flushing was conducted to count and classify embryos. There were more follicles (3.4 ± 1.1) in does administered 80 mg of pFSH (p < 0.05) than in goats administered 145 mg of pFSH (2.2 ± 1.1) and 215 mg of pFSH (0.9 ± 0.6). Numbers of corpora lutea, blastocysts, and recovered and transferable embryos of goats administered 145 mg pFSH (13.4 ± 3.7, 2.42 ± 1.0, 3.4 ± 1.2 and 3.2 ± 1.1, respectively) and those of goats administered 215 mg pFSH (11.6 ± 2.6, 3.2 ± 0.9, 5.7 ± 1.5, and 5.6 ± 1.5) were greater (p < 0.05) than values obtained from goats administered 80 mg pFSH (4.0 ± 1.5, 0.5 ± 0.3, 1.0 ± 0.5, and 0.8 ± 0.5). Numbers of morula of does administered 80 and 145 mg pFSH (0.4 ± 0.4 and 0.8 ± 0.3) were lower (p < 0.05) than those obtained from animals treated with 215 mg pFSH (2.4 ± 0.9). There was no effect of season upon the analyzed variables. In conclusion, under the prevalent conditions in north‐eastern Mexico, administration of 145 or 215 mg pFSH in a decreasing dose schedule over 3.5 days to bred goats provided a satisfactory superovulatory result. 相似文献
156.
AS Costa AS Junior GEN Viana MCS Muratori AM Reis APR Costa 《Reproduction in domestic animals》2014,49(5):E53-E55
This study aimed at evaluating the effects of angiotensin‐converting enzyme inhibitor (enalapril) and angiotensin II antagonist (valsartan) on the oestradiol and progesterone production in ewes submitted to oestrous synchronization protocol. The animals were weighed and randomly divided into three groups (n = 7). A pre‐experiment conducted to verify the effectiveness and toxicity of enalapril (0.5 mg/kg LW) and valsartan (2.2 mg/kg LW) showed that, in the doses used, these drugs were effective in reducing blood pressure without producing toxic effects. In the experiment, all animals were subjected to oestrous synchronization protocol during 12 days. On D10, D11 and D12, animals received saline, enalapril or valsartan (same doses of the pre‐experiment), according to the group randomly divided. The hormonal analysis showed an increase in oestradiol on the last day of the protocol (D12) in animals that received enalapril (p < 0.05), but not in other groups, without changing the concentration of progesterone in any of the treatments. It is concluded that valsartan and enalapril are safe and effective subcutaneously for use in sheep and that the angiotensin‐converting enzyme (ACE) inhibition with enalapril leads to an increase in oestradiol production near ovulation without changing the concentration of progesterone. This shows that ACE inhibition may be a useful tool in reproductive biotechnologies involving induction and synchronization of oestrus and ovulation in sheep. 相似文献
157.
Intense anthropogenic exploitation has altered distribution of forest resources. This change was analyzed using visual interpretation of satellite data of 1979, 1999 and 2009. Field and interactive social surveys were conducted to identify spatial trends in forest degradation and data were mapped on forest cover and land use maps. Perceptions of villagers were compiled in a pictorial representation to understand changes in forest resource distribution in central Himalaya from 1970 to 2010. For- ested areas were subject to degradation and isolation due to loss of con- necting forest stands. Species like Lantana camara and Eupatorium adenophorum invaded forest landscapes. Intensity of human pressure differed by forest type and elevation. An integrated approach is needed to monitor forest resource distribution and disturbance. 相似文献
158.
Vinti Agarwal B. M. Chauhan 《Plant foods for human nutrition (Dordrecht, Netherlands)》1988,38(2):189-197
Dietary fibre content of foods namely,khejri beans (Prsopsis cinceria),peepalbanti (Ficus religiosa),barbanti (Ficus bengalensis),gullar (Ficus glomerata) andteent (Capparis decidua) varied from 38.5% to 55.7%. Cellulose and lignin were predominating constituents inpeepalbanti,barbanti andgullar; hemicellulose inteent and pectin inkhejri beans. Fibre from all these plant foods, fed at the 10% dietary level to rats, induced a greater resistance to hyperlipidemia than cellulose.Teent had the most pronounced hypocholesterolemic effect which appeared to operate through increased fecal excretion of cholesterol as well as bile acids. Dietary hemicellulose showed a significant negative correlation with serum and liver cholesterol and a significant positive correlation with fecal bile acids. The dietary fibre influenced total lipids, cholesterol, triglycerides and phospholipids of the liver to varying extents. 相似文献
159.
Sharma Samriti Chauhan Arjun Kumar Raj Dobhal Sneha Kaur Rajinder Kumar Krishan Verma Kamlesh 《Genetic Resources and Crop Evolution》2022,69(1):11-38
Genetic Resources and Crop Evolution - Food is indispensable for fulfilling the nutritional requirements of living beings. The principal source of food, nutrition and feed are horticultural... 相似文献
160.
Modeling Soil Organic Carbon Dynamics in Response to Climate Change in Mount Everest Region of Nepal
Eurasian Soil Science - This study provides an estimate of soil organic carbon (SOC) stock, projects future SOC stocks under different climate change scenarios, and considers impacts on topsoil SOC... 相似文献