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排序方式: 共有186条查询结果,搜索用时 15 毫秒
71.
Sen Chauhan Indra Gupta Ashok K. Khate Keviletsu Chauhan Anuj Krishna Shankar Rao Thakur Pathak Shivendra Hazra Ritwik Singh Maneesh 《Tropical animal health and production》2010,42(8):1809-1815
The objective of the study was to evaluate the effects of genetic and non-genetic factors on production of breeding bulls
and semen quality parameters in Karan Fries crossbred male by fitting least squares analysis. Genetically, the animals were
divided into three subclasses. The non-genetic factors were season of birth, period of birth, and age group with three subclasses
each for season of birth and period of birth. Age group was classified into four subclasses. The traits generated in the study
were number of males reaching semen donation stage (AFSC) and first freezing (AFSF), age at last semen collection (ALSC) and
last freezing (ALSF), age at disposal (AD), and lifetime semen production traits (up to 1 year after first freezing). The
effect of period of birth was significant for AFSC, AFSF, ALSC, and AD. It was also significant for total ejaculates produced
in a year. The age group had significant effect on AFSF. Effect of genetic group was significant for freezable ejaculates
produced in a year, for frozen semen doses produced in a year, and for number of ejaculates cryoprocessed in a year. Season
had no statistically significant effect on any of the traits studied. The influence of period revealed that the most of the
traits of breeding bulls improved after intermediate period, which could be due to better care, training, feeding, and other
management practices in the latter years. However, no consistent trend could be established for the effects of genetic groups
and other non-genetic causes on the traits considered. 相似文献
72.
P. N. Sivalingam Dhurendra Singh Sarita Chauhan 《Genetic Resources and Crop Evolution》2012,59(2):305-316
Twenty two germplasm accessions of Cordia myxa were collected from Rajasthan and established at the field gene bank for conservation and evaluation. Morphological characterization
of 10 year-old trees for 17 traits indicated wide variations among the accessions tested. Higher number of flowers per cyme
was found in accession ACHM11 and higher pulp:stone ratio in AHCM25. Overall, AHCM22 was found to be a superior germplasm
line for most of the horticulturally useful traits among the accessions tested as it had higher percent of fruit set, pulp:stone
ratio and fruit weight. High significant positive correlation was obtained between leaf, fruit characters and pulp:stone ratio.
However, these characters were found to be negatively correlated with number of flowers per cyme. Out of 50 random decamer
primers used for random amplification (RAPD), 25 were polymorphic. Average polymorphism resolved by these markers among these
accessions was 69.8% with an average polymorphic information content of 0.43. Genetic diversity revealed by Jaccard’s co-efficient
was between 0.44 and 0.94, and three major clusters were identified among these accessions by phylogenetic analysis using
NTSYSpc-2.02e software. RAPD markers associated with leaf size and pulp:stone ratio were also identified. This study shows
the existence of high genetic diversity among these accessions. 相似文献
73.
K Sirisha NL Selokar M Saini P Palta RS Manik MS Chauhan SK Singla 《Reproduction in domestic animals》2013,48(4):538-544
This study was carried out to compare the post‐thaw cryosurvival rate and the level of apoptosis in vitro produced zona‐free cloned buffalo blastocysts subjected to slow freezing or vitrification in open‐pulled straws (OPS). Zona‐free cloned embryos produced by handmade cloning were divided into two groups and were cryopreserved either by slow freezing or by vitrification in OPS. Cryosurvival of blastocysts was determined by their re‐expansion rate following post‐thaw culture for 22–24 h. The post‐thaw re‐expansion rate was significantly (p < 0.05) higher following vitrification in OPS (71.2 ± 2.3%) compared with that after slow freezing (41.6 ± 4.8%). For examining embryo quality, the level of apoptosis in day 8 frozen‐thawed blastocysts was determined by TUNEL staining. The total cell number was not significantly different among the control non‐cryopreserved cloned embryos (422.6 ± 67.8) and those cryopreserved by slow freezing (376.4 ± 29.3) or vitrification in OPS (422.8 ± 36.2). However, the apoptotic index, which was similar for embryos subjected to slow freezing (14.8 ± 2.0) or OPS vitrification (13.3 ± 1.8), was significantly (p < 0.05) higher than that for the control non‐cryopreserved cloned embryos (3.4 ± 0.6). In conclusion, the results of this study demonstrate that vitrification in OPS is better than slow freezing for the cryopreservation of zona‐free cloned buffalo blastocysts because it offers a much higher cryosurvival rate. 相似文献
74.
Effects of a short‐term supranutritional selenium supplementation on redox balance,physiology and insulin‐related metabolism in heat‐stressed pigs 下载免费PDF全文
F. Liu P. Celi J. J. Cottrell S. S. Chauhan B. J. Leury F. R. Dunshea 《Journal of animal physiology and animal nutrition》2018,102(1):276-285
Heat stress (HS) disrupts redox balance and insulin‐related metabolism. Supplementation with supranutritional amounts of selenium (Se) may enhance glutathione peroxidase (GPX) activity and reduce oxidative stress, but may trigger insulin resistance. Therefore, the aim of this experiment was to investigate the effects of a short‐term high Se supplementation on physiology, oxidative stress and insulin‐related metabolism in heat‐stressed pigs. Twenty‐four gilts were fed either a control (0.20 ppm Se) or a high Se (1.0 ppm Se yeast, HiSe) diet for 2 weeks. Pigs were then housed in thermoneutral (20°C) or HS (35°C) conditions for 8 days. Blood samples were collected to study blood Se and oxidative stress markers. An oral glucose tolerance test (OGTT) was conducted on day 8 of thermal exposure. The HS conditions increased rectal temperature and respiration rate (both p < .001). The HiSe diet increased blood Se by 12% (p < .05) and ameliorated the increase in rectal temperature (p < .05). Heat stress increased oxidative stress as evidenced by a 48% increase in plasma advanced oxidized protein products (AOPPs; p < .05), which may be associated with the reductions in plasma biological antioxidant potential (BAP) and erythrocyte GPX activity (both p < .05). The HiSe diet did not alleviate the reduction in plasma BAP or increase in AOPPs observed during HS, although it tended to increase erythrocyte GPX activity by 13% (p = .068). Without affecting insulin, HS attenuated lipid mobilization, as evidenced by a lower fasting NEFA concentration (p < .05), which was not mitigated by the HiSe diet. The HiSe diet increased insulin AUC, suggesting it potentiated insulin resistance, although this only occurred under TN conditions (p = .066). In summary, HS induced oxidative stress and attenuated lipid mobilization in pigs. The short‐term supranutritional Se supplementation alleviated hyperthermia, but did not protect against oxidative stress in heat‐stressed pigs. 相似文献
75.
The role of the reticuloendothelial system in the immunopathology of Marek's disease 总被引:1,自引:0,他引:1
The role of macrophages in immunity against Marek's disease (MD) was studied. Chickens of one group were subjected to depletion of macrophages using repeated doses of Francil amorphous silica and those of another group were subjected to activation of macrophages using repeated doses of brewer's thioglycollate broth. Chickens of a third group were vaccinated with herpesvirus of turkeys FC 126 vaccine followed by depletion of macrophages. Chickens of these three groups, as well as groups of healthy unvaccinated and healthy vaccinated chickens, were challenged with virulent MD virus. A sixth group of healthy uninfected chickens was kept as a control. The results, based on clinical signs, gross and histopathological studies and agar gel precipitation test (AGPT) for antibodies, indicated that activation of macrophages enhanced immunity against MD and depletion of macrophages had the opposite effect. The protective effect of vaccination against MD was also lowered by depletion of macrophages. The results of AGPT indicated retardation of MD virus replication by macrophage activation and the reverse on depletion. 相似文献
76.
Pyometra was recorded in five camels and Actinomyces pyogenes (Corynebacterium pyogenes) was isolated from pus of the affected camels. 相似文献
77.
R K Tamang G J Jha M K Gupta H V Chauhan B K Tiwary 《Veterinary immunology and immunopathology》1988,19(3-4):299-305
Cypermethrin toxicity was produced in mice by intra-peritoneal injection of the pesticide at 50 mg/kg body weight per day for 26 days, and in goats by drenching with cypermethrin at 41.6 mg/kg body weight per day for 30 days. The status of cell-mediated immunity (CMI) was assessed by the 2,4-dinitrofluorobenzene (DNFB) skin sensitivity test. The results indicated significant depression of CMI in the cypermethrin-treated mice and goats. In addition, the humoral immune reaction of the goats intoxicated with cypermethrin was estimated by enumeration of the plaque-forming B-lymphocytes. The rate of plaque formation in the lymphocyte suspension of cypermethrin-treated goats was significantly reduced and the diameter of the plaques was also significantly lower than in that of control animals. The results indicated that cypermethrin suppressed both CMI and the antibody-forming ability of lymphocytes. This immunosuppressive action of cypermethrin is being reported for the first time. 相似文献
78.
Five short-duration pigeonpea (Cajanus cajan (L.) Millsp.) genotypes were grown at three plant populations in three locations during the 1986 and 1988 rainy seasons, to determine the physiological basis of observed variations in yield. Significant differences were found in seed yield (Y), crop growth rate (C), and the durations of vegetative (Dv) and reproductive (Dr) growth, and partitioning (P). These were attributable to genotypes and their interactions with environments (except for C). Variation in C, Dr, and P together explained 78 % of the observed variation in Y due to different genotypes and environments. Crop growth rate alone contributed about 71 % of the variation in Y, and reached an optimum value of around 6.5 kg ha?1°Cd?1. Crop growth rates increased with the duration of the vegetative period and with plant population. However, a negative relationship between C and P resulted in plant population having little effect on seed yield. The maximum-yielding genotype, ICPH 8 had the highest C and an intermediate P. 相似文献
79.
Subsurface drain spacing is underestimated by the equations that do not account for evaporation-evapotranspiration (ET) lowering the water table in drained lands. An analytical solution is proposed to evaluate water table behaviour in subsurface drained lands in the presence of ET. A piecewise linear model is proposed and used to describe any realistic functional relation between ET and depth to water table. Characteristics of the solution have been highlighted with the help of numerical examples for which drainage parameters have been chosen from two actually operating drainage systems installed in semi-arid regions. The accuracy of the proposed solution has been verified with the existing numerical scheme as well as by comparing the water table behaviour with the observed field data. Application of the solution in subsurface drainage design has been illustrated which suggests that drain spacing at this particular site could be increased by 9 to 18% if the contribution of ET in lowering the water table is taken into account. 相似文献
80.