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51.
Oestrus synchronisation, fertility and kidding behaviour were studied in 44 Black Bengal goats. They were divided into six experimental groups: group 1, control; group 2, progesterone; group 3, progesterone, pregnant mare serum gonadotrophin (PMSG) and human chorionic gonadotrophin (HCG); group 4, prostaglandin F2 alpha (PGF2 alpha); group 5, PGF2 alpha, PMSG and HCG; group 6, PMSG and HCG. There was 100 per cent synchronisation of oestrus in the groups treated with progesterone, progesterone with PMSG and HCG, and prostaglandin with PMSG and HCG. In the other two treated groups the synchronisation was between 66 and 75 per cent. In the control group only 50 per cent of the animals came into oestrus during the period of observation. The duration of oestrus varied between 19 and 24 hours except in group 5 where it was 40.87 hours. Animals came on heat between 95 and 137 hours after treatment except in group 5 where the interval was only 18.87 hours. A maximum fertility of 75 per cent was observed in group 4 while the kidding percentage was greatest in group 2. There appeared to be no beneficial effect of superovulation on the number of kids produced. Gestation length was similar in all the groups. 相似文献
52.
Pandey JP 《Science (New York, N.Y.)》2006,311(5766):1376-7; author reply 1376-7
53.
Purpose
The aim of the present investigation was to document the phytotherapeutic knowledge and veterinary healthcare management practices among the Tharu tribal community of Uttar Pradesh, India and to determine the consensus of such practices, in order to evaluate the potential for new veterinary drugs of herbal origin. 相似文献54.
India is the world’s tenth most forested nation with 76.87 M ha of forest and tree cover occupying 23.4% of its geographical
area. Forests—with their intrinsic of carbon sequestration and storage values—are in the front line of India’s climate change
mitigation strategies. This paper provides estimates of sequestered carbon in India’s forest and tree cover for the years
1995 and 2005 as per the IPCC good practice guidelines method. It is based on the primary data for the soil carbon pool through
collecting soil samples by laying out quadrats across the country and secondary data for the growing stock of all forest and
tree cover in the country. The estimates are compared with current and future projected emissions. It is found that conservation
policies have resulted in increase of the country’s forest carbon stocks from 6244.8 to 6621.6 Mt with an annual increment
of 37.7 Mt of the carbon from 1995 to 2005. Annual CO2 removal by the forests is enough to neutralise 9.3% of the country’s 2000 level emissions. Continued removals by the forest
and tree cover would offset 6.5 and 4.9% of India’s projected annual emissions in 2010 and 2020 respectively. Economically,
the annual value of this forest carbon in the international market is about US $188 million. The result is of use in the REDD
and REDD+ context for India. 相似文献
55.
Madhav Pandey Oliver Gailing Hans H. Hattemer Reiner Finkeldey 《European Journal of Forest Research》2012,131(3):739-746
Knowledge of SGS in plants is vital to understand the ecological and evolutionary dynamics of populations and to plan conservation
strategies. Some of the major factors that can affect spatial genetic structure (SGS) in plants are the level of gene flow,
spatial arrangement and life stages of individuals within populations. Applying six highly variable microsatellite markers,
we investigated the effect of these factors on spatial genetic structure selecting two natural populations of sycamore maple,
which is an insect-pollinated, autotetraploid and an indigenous hardwood species in Germany and in other central European
countries. The two study populations had different shapes (“compact” and “elongated”) and tree densities. Significant SGS
extended to ~180 m in the elongated population and to ~35 m in the compact population. Juvenile plants of the compact population
showed significant SGS up to 40 m. Estimate of Sp statistic in high-density population was almost double of that in the population
with low density. Gene dispersal distance in the low-density population was about 9 times higher than in the population with
high density. The similar level of significant SGS in both adult and juvenile plants suggested minimal or no effect of life
stages of individuals on SGS in the sycamore maple population. The data presented in this study can provide guidelines for
seed collection and to establish populations for the conservation and management of genetic resources of the species. 相似文献
56.
Paddy and Water Environment - Environmental flow is necessary to maintain a healthy ecosystem and sustain aquatic lives. Its assessment is thus aimed at analysing the minimum flow of water required... 相似文献
57.
Akash Tariq Kaiwen Pan Olusanya Abiodun Olatunji Corina Graciano Ningning Li Zilong Li Dagang Song Feng Sun Meta Francis Justine Dan Huang Shanxing Gong Bikram Pandey Muhammad Idrees Mohammed A. Dakhil 《植物养料与土壤学杂志》2019,182(4):586-596
Drought is one of the major environmental stresses altering forest productivity. However, nutrient availability can modulate drought resistance. Phoebe zhennan (gold Phoebe) is a high‐quality timber‐producing but threatened tree species in China, facing serious anthropogenic disturbances and abiotic constraints that restrict its growth and development. However, little attention has been given to designing adaptive strategies for its management by evaluating the possible role of major nutrients, particularly nitrogen (N), on its morphological and physio‐biochemical responses under water stress. To evaluate these responses, a complete randomized design was followed to investigate the effects of two irrigation levels (well‐watered and drought‐stressed conditions) and N fertilization treatments (with and without N). Drought stress significantly affected the growth of seedlings, as indicated by impaired photosynthesis, pigment degradation, disrupted N metabolism, over‐production of reactive oxygen species and enhanced lipid peroxidation. Nitrogen supplementation under drought stress had remarkable positive effects on the growth through physio‐biochemical adjustments as shown by higher level of nitrogenous compounds and up‐regulation of N‐associated metabolic enzymes activities which might be due to N‐mediated improved leaf relative water contents and photosynthetic efficiency. In addition, N application reduced oxidative stress and membrane damage, and maintained a high accumulation of osmolytes. However, in well‐watered seedlings N fertilization significantly improved root biomass and net CO2 assimilation rate suggesting high N‐use efficiency of the seedlings. These findings reveal that drought significantly affects the growth of P. zhennan, while N fertilization plays a crucial role in alleviating water stress damage by improving its drought tolerance potential at low metabolic costs. Therefore, N fertilization could be considered as an effective strategy for the conservation and management of P. zhennan in the face of future climate change. 相似文献
58.
59.
Moderate to high heterosis for yield and ten related characters was studied in 45 crosses involving six indica (I) and four
tropical japonica (J) varieties of rice under three (E1-optimum sowing and high fertility, E2-both optimum sowing and fertility and E3- late sowing and high fertility) environments. Trends of magnitude of heterosis for grain yield and plant height were I/J
> I/I > J/J and for days to 50% flowering I/J > J/J > I/I hybrids. Estimates of standard heterosis (%) for grain yield were
–64.5 to 146.1 in E1, –70.4 to 82.2 in E2 and –67.2 to 63.8 in E3. Environment E1 seemed to be more favorable for higher heterosis expression than others. Higher heterosis in yield also accompanied heterosis
in panicle number, dry matter and spikelet and grain number per panicle. Most estimates for days to flower were negative.
Heterotic I/J hybrids also recorded maximum heterosis for earliness. Moderate to low standard heterosis for plant height across
environments (2.0 to 13.7%) was recorded. Hybrids were identified in specific environments for direct exploitation
in hybrid breeding. Hybrids B4116 / Sarjoo 52, B4122 / Pant Dhan 4 and B4122 / Narendera 359 were more stable than others
over three environments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
60.
M. T. Shilta Narinder Kumar Chadha P. K. Pandey Paramita Banerjee Sawant 《Aquaculture International》2016,24(2):661-674
An experiment was conducted to compare the efficiency of biofilm production in natural and artificial substrates and to study their effect on water quality and growth of Etroplus suratensis. Four different substrates were used for biofilm formation: paddy straw (T1), sugarcane bagasse (T2), polyvinylchloride (PVC) pipe (T3) and plastic sheet (T4). The experiment was carried out in mud-bottomed fibre-reinforced plastic tanks (300 L) in triplicates. About 3000 cm2 surface area (600 g) of each substrate was suspended in water supplemented with fertilizers. Only cow dung and urea were applied in control tanks. The tanks were stocked with 25 fishes with average weight of 9.1 ± 0.22 g. The overall mean value of heterotrophic bacteria in substrate was found higher in straw followed by bagasse, plastic and PVC. The dominant genera of bacteria in the substrate were Bacillus, Pseudomonas and Micrococcus in that order of preponderance. The mean phytoplankton and zooplankton density on the substrates were higher in bagasse followed by straw, plastic and PVC. The biofilm developed on the substrate significantly reduced the ammonia nitrogen and nitrite-nitrogen content of water. The growth of fishes was significantly (P < 0.05) higher in substrate-based treatments than that in the control with better results in bagasse followed by straw, plastic and PVC. The conclusions of the present study are that biofilm produced on natural substrates, especially on bagasse, enhanced growth of E. suratensis and reduced the necessity of water exchange during the culture, which certainly decreases the cost of Etroplus production. 相似文献