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111.
Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus–oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress.  相似文献   
112.
ABSTRACT

Lack of crop diversification with suitable vegetable-based cropping system is a major constraint in limiting the productivity and sustainability of north-western Indian sub-Himalayas. To find out a sustainable vegetable-based cropping system in this region, a three year colocasia-based vegetable intensive experiment was conducted at Hawalbagh, Almora, India in a sandy clay loam soil under sub-temperate climatic conditions. Seven colocasia-based vegetable cropping systems along with rice–wheat system were compared under recommended package and practices. The system productivity in terms of colocasia equivalent yield was highest under colocasia–onion–frenchbean (52.38 Mg ha?1) system. Sustainable yield index was highest with colocasia–gardenpea–frenchbean system (0.86). After 3 years, total soil organic carbon (0–5%), available N (2–22%), P (–7% to 14%) and K (3–15%) concentrations were increased in all cropping systems except rice–wheat system, where negative balance of available P (7%) was observed over that of initial soil. Significantly higher soil microbial activity, soil carbohydrate, dehydrogenase, protease, acid and alkaline phosphatases activity were observed under colocasia–onion system. The results suggest that colocasia–onion–frenchbean system with higher productivity improves soil fertility and enhances enzymatic activities.  相似文献   
113.
The objective of this study was to elucidate the changes in circulating levels of plasma interleukin-8 (IL-8) during peripartum period in Murrah buffaloes (Bubalus bubalis). IL-8 was estimated in blood plasma of healthy peripartum Murrah buffaloes (n = 6) on days ±30, ±15, ±5, ±3, ±1 and 0 pre- and postpartum with respect to the day of parturition (day 0) in each of the two different seasons (hot–humid and spring). The mean microclimate Temperature–Humidity Index (THI) during spring season was significantly lower (p < 0.01) than the corresponding THI in hot–humid season. In both the seasons, plasma IL-8 remained lower in prepartum period (≤46.56 ± 14.08 pg/ml during spring and ≤ 73.18 ± 18.56 pg/ml during hot–humid season) than in the postpartum period (≥51.41 ± 13.82 pg/ml during spring and ≥ 84.13 ± 16.97 pg/ml in hot humid season). During spring, the IL-8 levels were significantly higher (P < 0.05) on days +5 and +15 postpartum in comparison to the IL-8 levels on days −30, −5, and −3 prepartum. During hot–humid season, IL-8 level was significantly higher (P < 0.05) on day +30 as compared to the IL-8 levels on days −30 and −5 prepartum. The correlation between IL-8 and mean microclimate THI was significant (r = 0.25, P < 0.01). From the results, it is concluded that peripartum period in buffaloes is associated with an inflammatory response leading to significantly higher plasma IL-8 during parturition and postpartum period than in the pre-partum period.  相似文献   
114.
Members of heat shock protein 70 (HSP70) are highly conserved proteins of about 70 kDa and play important roles in protein folding. Levels of these proteins increase when cells are under stress. Environmental temperature influences both the basal and induced levels of HSPs. However, studies on HSPs in fishes from a tropical country such as India are lacking. In the present study, Indian major carp (IMC) Cirrhinus mrigala (Ham.) acclimatized at 25±2°C had high levels of HSP70, viz., 1.2–1.3 ng μg?1 total protein in kidney and gill and 4.2–5.3 ng μg?1 total protein in liver and brain tissues, indicating the presence of biochemically significant levels of stress. However, maintenance of acclimatized fish at 17°C for up to 48 h did not lead to a significant decrease in stress protein levels. A heat shock at 37°C for up to 48 h resulted in only two to threefold increase in HSP70 levels in these organs. Although the increase in HSP70 levels was apparent from the first hour of heat stress in all these tissues, the increase was significant from the second hour in the brain, the sixth hour in liver and kidney and the 20th hour in the gills.  相似文献   
115.
116.
Tropical Animal Health and Production - A study was conducted to analyze the dairy farming sector of Bangladesh from an economic viewpoint. Primary data was collected from smallholder dairy farms...  相似文献   
117.
Aquaculture International - Pacific white shrimp (Penaeus vannamei) farming is an important commercial aquaculture production system contributing substantially to the economic and societal...  相似文献   
118.
  • 1. Three classes of habitat used by groups of fish species classified as conservation and management priorities were developed for the Gerua River (also known as the Girwa River, Karnali River) in the Ganges river basin. This river is large (mean annual discharge ca 1500 m3 s?1, up to 900 m wide), surrounded by protected lands of India and Nepal, and upstream of major diversions and river alterations.
  • 2. Fish and habitat sampling was conducted at 45 sites from 2000 to 2003. Data were analysed for 2172 fish of 14 species. Species and life stages found occupying a statistically distinct subset of the river habitats were grouped to identify classes of river habitat for conservation.
  • 3. Most species and life‐stage groups specialized on specific habitat conditions revealed by multivariate analyses of variance and a principal component analysis. The most numerous and diverse group (six species, 15 life stages) was associated with deep depositional habitats with sandy substrate. Two species covering three life stages were primarily oriented to erosional habitat marked by fast current velocity with pebble and cobble substrate. A third group of three species of adults and juveniles were intermediate in habitat use.
  • 4. River conservation for fish faunas should maintain both erosional and depositional channel habitats with depths, substrates, and current velocity inclusive of the ranges reported. The erosional and depositional nature of the key habitats requires that rivers be maintained with flows capable of channel‐forming functions.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
119.
The present study was conducted to evaluate the effect of histamine and to characterise its receptor subtypes in reticular groove (RG) smooth muscle of adult goats. The studies were done using floor and lip regions of RG. We used tension experiments on smooth muscle of RG isolated from adult goat for functional characterisation of H1 and H2 receptors. Western blotting and immunohistochemistry experiments were conducted for molecular characterisation of these receptors. Histamine evoked concentration-dependent contraction of isolated RG circular and longitudinal smooth muscle preparation. Pyrilamine antagonised the action of histamine. Histamine did not induce any relaxant effect on RG preparations. Additionally, cimetidine did not produce any significant effect on histamine-induced response. Non-selective histaminic receptor antagonist cyproheptadine attenuated the contraction response to histamine in the smooth muscle. Molecular characterisation and localisation of H1 and H2 receptor proteins confirmed the presence of these receptors in RG. It is most likely that histamine-induced contractile effect in RG smooth muscle of goats is mediated by H1 histaminic receptors.  相似文献   
120.
An experiment was conducted to assess the effect of supplementation of cellulolytic gut bacterium with plant protein‐based diet on growth, digestibility and digestive enzyme status of tiger shrimp, Penaeus monodon. Bacillus sp. DDKRC1. (JN641289), a potential cellulolytic bacterium, isolated from the gut of Asian seabass was used as feed supplement in this experiment. The shrimps of group I, II and III were fed with control diet (without bacterial supplement, D1), diet supplemented with live Bacillus sp. DDKRC1. at 2.94 × 10cfu per 100 g feed (D2) and diet fermented (48 hr) with same bacteria (D3) respectively. At the end of the 42 days experiment, shrimps of group II showed significantly better (< .01) growth and protein efficiency ratio (PER) and lower (< .01) feed conversion ratio (FCR) as compared to group I and III. Dry matter, cellulose, hemicellulose and lipid digestibilities were significantly (< .01) higher in group II than other two groups. Cellulase, amylase and protease activities in the gastrointestinal (GI) tract were significantly (< .01) higher in group II as compared to other two groups. Total heterotrophic count, amylolytic, cellulolytic and proteolytic bacterial counts in gut were significantly (< .01) higher in group II as compared to other two groups. Haematological analysis indicated better (< .05) immune response in groups II and III than control group. Diets D2 and D3 showed better effect on growth, digestibility, FCR, survival and immune response of P. monodon as compared to D1.  相似文献   
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