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11.
Arslan Qayyum Usman Arshad Muhammad Rizwan Yousuf Nasim Ahmad 《Tropical animal health and production》2018,50(3):555-560
The aim of this study was to determine the effect of breeding method and season on pregnancy rate and cumulative embryonic and fetal losses in Nili-Ravi buffalo. Estrus detection was performed twice a day by teaser buffalo bull for 1 hour each. A 2?×?2 factorial design was used to address the breeding method and season. Buffaloes (n?=?130) exhibiting estrus were randomly assigned to be bred either in peak breeding season (PBS; n?=?80) or low breeding season (LBS; n?=?50). Within each season, buffaloes were divided to receive either natural service (NS; n?=?65) or artificial insemination (AI; n?=?65). NS buffaloes, in estrus, were allowed to remain with the bull until mating. AI was achieved, using frozen thawed semen of bull of known fertility. PBS comprised of September to December and LBS were from May to July. Serial ultrasonography was performed on days 30, 45, 60, and 90 after breeding (day 0) to monitor pregnancy rate and embryonic and fetal losses. The pregnancy rate on day 30 after breeding was higher in NS as compared to AI group (63 vs. 43%; P?<?0.05) during PBS while it did not differ (48 vs. 32%; P?>?0.05) in LBS. The cumulative embryonic and fetal losses between days 31 and 90 were significantly lower in PBS than LBS (33 vs. 60%; P?<?0.05), ignoring breeding method. Pregnancy rates were better with NS in PBS, and cumulative embryonic fetal losses were higher in LBS in Nili-Ravi buffalo. 相似文献
12.
M. Abdullah Yousuf Akhond M. Abul Hossain Molla M. Obaidul Islam Mohammad Ali 《Euphytica》2000,114(3):175-180
Interspecific cross compatibility between cultivated and wild okra (Abelmoschus esculentus and A. moschatus) and pollen tube growth behaviour in the crosses among a local cultivar of A. esculentus, A. moschatus and their F1s were studied. Fruit set was observed in all the crosses except one and seed setting was absent in two of the crosses which
set fruit. All seed produced were shrivelled but F1 plants were obtained from two crosses where cultivated okra was used as the seed parent. The F1 plants were perennial in nature with very low pollen viability and seed set. A high percentage of pollen germination and
profuse pollen tube penetration in the style were observed in the cross A. esculentus × A. moschatus but low pollen tube penetration with abnormal pollen tubes was observed in the reciprocal cross. The number
of pollen tubes was very low but they appeared to be normal in the backcross A. esculentus × F1, but were generally abnormal in the reciprocal cross. Both pre- and postzygotic barriers seemed to occur in crosses between
the two species. The present studies indicate that these barriers can be overcome and desirable characters from A. moschatus transferred to cultivated okra using conventional hybridisation techniques.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
旨在探索多浪羊（D组）与小尾寒羊（X组）皮下脂肪组织中的特异性表达基因,并研究其潜在的作用,为理解绵羊脂肪组织发育规律以及对脂代谢相关疾病的预防和治疗研究提供依据。本研究选取脂肪沉积能力存在差异、健康无病、体况良好、种内个体体重相近（约50 kg）的雌性成年多浪羊和小尾寒羊为试验材料,分为D组（试验组）和X组（对照组）,每组3个重复,采集位于背最长肌的皮下脂肪组织,应用RNA-Seq技术和生物信息学方法进行转录组测序并对结果进行分析。以|Fold change|≥2,P adjust≤0.05为标准筛选差异表达基因,通过对差异表达基因进行GO功能注释和KEGG通路富集分析,得到与脂肪沉积和脂代谢有关的差异基因。为了验证测序数据的可靠性,本研究随机选取了6个差异表达基因进行qRT-PCR验证。结果显示,在6个样本中共检测到38 672个已知的mRNAs,新的mRNAs为1 606个,在两组中共有839个差异表达基因,其中有320个差异基因在多浪羊组中上调表达,有519个差异基因在多浪羊组中下调表达。通过GO功能注释分析发现,差异表达基因主要参与脂质分解代谢过程、脂质生物合成过程、脂质分解代谢负调控过程、MAPK级联反应调控、对甘油三酯的反应等生物学过程。KEGG通路富集结果显示,差异表达基因显著富集到了PI3K-Akt、MAPK、胰岛素以及PPAR等信号通路中。qRT-PCR结果与测序结果一致,表明测序结果可靠。通过对多浪羊和小尾寒羊皮下脂肪组织进行转录组测序以及生物信息学分析,筛选到与脂肪沉积和脂代谢相关的差异表达基因,这些基因主要参与脂质生物合成、脂质代谢等过程,其中COL1A1、AKT2、SCD、LPL、PCK1与PPP2R5A可能在多浪羊与小尾寒羊的皮下脂肪组织的沉积与代谢中发挥重要作用。 相似文献
14.
Bhat SU Sofi AH Yaseen T Pandit AK Yousuf AR 《Pakistan journal of biological sciences: PJBS》2011,14(3):182-194
This study analyses a macroinvertebrate community survey for River Sindh and its tributary including Baltal, Yashmarg, Sonamarg and Thajwas Grar considering the extreme hydrological conditions linked with the seasonal low-flow period typical for some streams in this area. This study attempts to provide an overview of the macro invertebrate assemblages and physico-chemical variables of the River Sindh and its important tributary. Four study sites were selected from the River Sindh and its tributary including Baltal, Yashmarg, Sonamarg and Thajwas Grar for studying the ecological distribution of Macroinvertebrate assemblages. Totally, 33 taxa of macroinvertebrates were recorded from the two streams belonging to Mollusca-3 (Gastropoda-2 and Bivalvia-1), Annelida-1 and Arthropoda-29 (Insecta-29). Among insects Ephemeroptera (7), Trichoptera (6) and Diptera (13) dominated. Except Yashmrag all sites were found devoid of annelids while as the mollusks were found absent at Sonamarg. Highest values of Shannon Weiner Index were found at Yashmarg (2.42) and lowest at Sonamarg (1.99) while as highest and lowest Sorensen's similarity coefficient were found between Baltal/Thajwas Grar (0.68) and Yashmarg/Thajwas Grar (0.39), respectively. A perusal of the data on physico-chemical characteristics showed that these streams were hard water type with high dissolved oxygen content. The ionic composition of the stream waters revealed the predominance of bicarbonate and calcium. Insecta dominated both qualitatively as well as quantitatively and the study revealed that the substrate compositions dominated by gravel, pebble and leaf litters are primary determinants of the invertebrate community structure recording maximum species diversity and abundance. Sample locations impacted by Amarnath yatris pilgrimage comparatively reflected slightly higher increase in nutrients than Thajwas Grar almost devoid of pilgrimage effect. 相似文献
15.
Shujauddin Mohammed Rajkumar Hemalatha Syed Shah Yousuf Hussain Qadri Vure Venkata Annapurna 《Journal of animal physiology and animal nutrition》2019,103(2):687-694
Semi‐synthetic diets (SSD) are recommended and are widely used to carry out experiments in rodents. However, in our experiments planned to carry out generation studies in female Golden Syrian hamsters using semi‐synthetic diets, it was observed that the hamsters did not conceive as a result of decreased food intake. In this paper, we present the effects of both semi‐synthetic diets and natural source diets (NSD) on food intake, body weight and reproductive performance of this species. Four‐week‐old female hamsters were equally divided into 3 groups and initially acclimatized for 2 weeks on natural chow diet (NCD). Thereafter, they were fed either control diet, high fat diet (HFD) or low protein diet (LPD) based on semi‐synthetic/natural source ingredients until 12 weeks. Daily food intake and weekly body weights were monitored. Hamsters were kept for mating for about 2 weeks from 10th week onwards, during which the pregnancy confirmation test was done using standard vaginal smear examination. In all the groups fed SSD, the food intake was very poor, hamsters lost body weight and did not conceive, thus preventing us from carrying out further experiments. Hamsters fed NCD/NSD ingested more than twice as much as hamsters fed SSD (7–8 g/day/hamster against 3 g/day/hamster on average respectively). Based on the results of the current research, we conclude that the routinely used semi‐synthetic diet is not suitable for carrying out studies in female hamsters. We suggest that scientists must also consider the unusual biological characteristics of a given species besides other biological factors. It is therefore critical to select appropriate biological models and diets that provide optimal sensitivity and specificity to accomplish the research objectives. 相似文献
16.
K M Mujeeb Rahiman Yousuf Jesmi Ambat P Thomas A A Mohamed Hatha 《Aquaculture Research》2010,41(9):e120-e134
Eight hundred and eighty‐five strains of bacterial isolates from various samples associated with the natural habitat of Macrobrachium rosenbergii were screened for their probiotic potential. Two putative probionts namely Bacillus NL110 and Vibrio NE17 isolated from the larvae and egg samples, respectively, were selected for experimental studies and were introduced to the juveniles of M. rosenbergii (0.080±0.001 g) through different modes such as through feed, water and both. The probiotic potential of the above bacteria in terms of improvements in water quality, growth, survival, specific growth rate (SGR), feed conversion ratio and immune parameters was evaluated. The treatment groups showed a significant improvement in SGR and weight gain (P<0.001). Survival among different treatment groups was better than that in the control group. There were also significant improvements in the water quality parameters such as the concentration of nitrate and ammonia in the treatment groups (P<0.05). Improvements in immune parameters such as the total haemocyte count (P<0.05), phenoloxidase activity and respiratory burst were also significant (P<0.001). It is concluded that screening of the natural microflora of cultured fish and shellfish for putative probionts might yield probiotic strains of bacteria that could be utilized for an environment‐friendly and organic mode of aquaculture. 相似文献
17.
Shabeena Yousuf Naqash 《Journal Of Aquatic Food Product Technology》2013,22(3-4):180-192
The focus of the study was to investigate the antioxidant activity of hydrolyzed muscle protein of Nemipterus japonicus and Exocoetus volitans. The trypsin protein hydrolysates of both fish showed maximum free radical scavenging potential and lipid peroxidation inhibition. Furthermore, it was purified by chromatographic methods followed by the lipid peroxidation inhibition; free radical scavenging assay was performed before and after purification. The purified peptide fractions of N. japonicus and E. volitans exhibited higher activity against polyunsaturated fatty acids (PUFA) peroxidation which was similar to natural antioxidants like α-tocopherol. Free radical scavenging potencies were measured by electron spin resonance technique (ESR). The purified peptide of E. volitans quenched free radicals (DPPH, hydroxyl, and superoxide) slightly more than N. japonicus. The amino acid composition of both fish protein hydrolysates showed variations in their ratio. The purified peptides were tested for cell cytotoxicity for Vero (kidney epithelial cells of the African Green Monkey) and Hep G2 (human hepatocellular liver carcinoma) cell lines. It was found that peptides did not show any cytotoxic effect for Vero cell lines and exerted a significant antiproliferative effect on Hep G2 cell lines. 相似文献
18.
Monogeneans are of great interest to the ecologists because of their simple life cycle and are considered as one of the important and sensitive parasites to any changes in water quality. The monogenean gill parasite, Diplozoon kashmirensis of the Carassius carassius was examined with the aim to evaluate the infection level and the factors influencing the infection. Our results showed that highest prevalence (34.22%) of D. kashmirensis was in the lake having high trophic status and least prevalence (10.90%) in the lake having least trophic status. Infection levels were significantly higher at the basins/sites having deteriorated water quality in comparison to the basins/sites having better water quality. The combined effect of pollutants and eutrophication showed decrease in intensity of D. kashmirensis in one of the polluted/hypertrophied site in the hypertrophic lake (Anchar Lake), while as synergistic effect (i.e. increase) on prevalence and intensity was observed in one of the polluted/hypertrophied site in the eutrophic lake (Dal Lake). Sex was not an important factor influencing the D. kashmirensis in three lakes. The study showed that condition factor was significantly higher in the hypertrophic lake and in an uninfected fish. In addition microhabitat influenced the Diplozoon infection. Most preferable site for the D. kashmirensis was middle sector of the gill. Furthermore, the gill parasite showed significantly positive correlation (r(p)=0.6, P<0.05) with water temperature in the hypertrophic lake, thus showing the impact of water temperature on this parasite. It was concluded that intra lake differences, season, condition factor, microhabitat and water temperature influenced the infection of D. kashmirensis. It seems from the data that eutrophic and hypertrophic habitats were favourable for the D. kashmirensis. The D. kashmirensis showed both antagonistic and synergistic response to the combined effect of pollution and eutrophication. 相似文献