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51.
Shadi Dayyani Shiv O. Prasher Chandra A. Madramootoo 《Agricultural Water Management》2010,98(1):55-68
A new watershed model, DRAIN-WARMF, was developed to simulate the hydrologic processes and the nitrogen fate and transport that occur in small, predominantly subsurface-drained, agricultural watersheds that experience periodic freezing and thawing conditions. In this modeling approach, surface flow is simulated using a watershed scale model, WARMF, and subsurface flow is estimated using a field-scale model for subsurface-drained shallow water table fields, DRAINMOD 5.1. For subsurface flow calculations, the watershed is subdivided into uniform cells, and DRAINMOD is run on each cell with inputs based on the individual hydrologic characteristics of the cell. The coupling results in a distributed parameter model that calculates the total flow at the outlet of a watershed as well as the nitrogen losses. The model was evaluated for the St. Esprit watershed, located approximately 50 km northeast of Montreal. Simulations were carried out from 1994 to 1996; data from 1994 and 1995 was used for model calibration and data from 1996 was used for model validation. The new model was able to adequately simulate the hydrologic response and nitrate losses at the outlet of the watershed. Comparing the observed daily flow/monthly nitrogen with the model's outputs over the validation period returned an R2 value of 0.74/0.86 and modeling efficiency of 0.72/0.83. This clearly demonstrates the model's ability to simulate hydrology and nitrogen losses occurring in small agricultural watersheds in cold climates. 相似文献
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53.
Sagar P Prasad JK Prasad S Gupta HP Das A 《Tropical animal health and production》2012,44(7):1697-1702
The present study was undertaken to evaluate the effect of L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor on serum nitric oxide, progesterone, estradiol profiles and estrous cycle length in buffaloes. Murrah buffaloes (n?=?16) exhibiting regular estrous cycles were randomly allocated to two groups of eight animals. In the treatment group, buffaloes were administered 400?mg/h?L-NAME over 2?h (total dose?=?800?mg) via the coccygeal artery and the aorta abdominalis on day 15 of the estrous cycle. In the control group, normal saline was infused on the same day of the cycle by the same route. Blood samples were collected every 4?h on days 15 and 16, and once daily from days 17 to 21 of the estrous cycle for the assay of progesterone, estradiol and nitric oxide. L-NAME treatment significantly (p?0.05) reduced serum nitric oxide concentration from 4?h of day 15 until day 20 of the cycle. Serum progesterone concentration increased significantly (p?0.05) between 0 and 20?h post treatment on day 15. The estrous cycle length was 19.8?±?0.36 and 23.6?±?0.17?days for control and treated group buffalo (p?0.05), respectively. It was concluded that treatment of buffalo with L-NAME in the late luteal phase of the estrous cycle inhibited serum nitric oxide concentration resulting in increased progesterone production and extension of the effective life of the corpus luteum, thus prolonging the estrous cycle length. 相似文献
54.
Hausman NE Singh S Tranel PJ Riechers DE Kaundun SS Polge ND Thomas DA Hager AG 《Pest management science》2011,67(3):258-261
BACKGROUND: A population of waterhemp in a seed maize production field in central Illinois, United States, was not adequately controlled after post‐emergence applications of herbicides that inhibit 4‐hydroxyphenylpyruvate dioxygenase (HPPD). RESULTS: Progeny from the field population survived following treatment with mesotrione, tembotrione or topramezone applied to the foliage either alone or in combination with atrazine in greenhouse experiments. Dose–response experiments indicated that the level of resistance to the HPPD inhibitor mesotrione is at least tenfold relative to sensitive biotypes. CONCLUSION: These studies confirm that waterhemp has evolved resistance to HPPD‐inhibiting herbicides. Copyright © 2011 Society of Chemical Industry 相似文献
55.
Mahesh Y Rao BS Suman K Lakshmikantan U Charan KV Gibence HR Shivaji S 《Reproduction in domestic animals》2011,46(5):832-839
The ability to rescue gametes from endangered or wildlife species and to subsequently produce viable embryos holds tremendous potential as a means to increase the population size of endangered or wildlife species. The objective of this study was to assess the developmental competence of gametes recovered from nilgai that had died because of foot and mouth disease outbreak. Oocytes collected from the ovaries of seven dead nilgais were allowed to mature in vitro and were tested for developmental potential by in vitro fertilization (IVF) with epididymal spermatozoa collected also post-mortem. The average number of oocytes (n = 517) recovered per ovary was 36.9, and the side (right or left), size and weight of the ovaries had no significant effect on the number and quality of oocytes recovered. In vitro maturation studies indicated that the proportion of matured oocytes (MII stage) at 18, 24 and 30 h was 55.6%, 63.4% and 63.6%, respectively. Furthermore, 43% of the matured oocytes cleaved following in vitro fertilization and 12% of the cleaved oocytes (6/49) developed to the 4-8 cell stage. These findings suggest that the gametes recovered from nilgai post-mortem could be utilized for in vitro production of embryos. 相似文献
56.
Krishna Murari Sharma Deendayal Sharma Shiv Singh Tomar Ganpat Singh Chauhan 《Archives of Agronomy and Soil Science》2013,59(1):61-71
A field experiment was conducted during the winter seasons between 2004 and 2006 to assess the role of balanced fertilization and bioregulators (foliar-applied brassinosteroid 0.5 mg I?1, thiourea 1000 mg I?1 and kinetin 10 mg I?1) in enhancing the productivity of wheat. Conjoint application of NPKSZn (120 kg N, 40 kg P2O5, 30 kg K2O, 40 kg S, 5.5 kg Zn ha?1) recorded maximum improvements in yield attributes and significantly out-yielded all the fertilization treatments with 14.90, 4.97 and 6.39% increments in grain yield compared with NPK, NPKS and NPKZn treatments, respectively. Nutrient (N, P, K, S, Zn) content and uptake were also improved significantly with balanced fertilization. Among the bioregulators, application of 0.50 mg I?1 brassinosteroid recorded maximum increments in grain yield (14.10%), followed by 10 mg I?1 kinetin (12.31%) and 1000 mg I?1 thiourea (9.92%), over control (4.99 t ha?1). Bioregulators significantly enhanced the uptake of nutrients (N, P, K, S, Zn) over control. NPKSZn treatment also gave the maximum net return (Rs. 51,209 ha?1). Among the bioregulators, brassinosteroid provided the maximum net return (Rs. 47,292 ha?1) and benefit:cost (B:C) ratio (3.37) followed by thiourea (Rs. 45,500 ha?1 and 3.35). Kinetin also provided yield advantage, however, it gave a significantly reduced B:C ratio compared with control. 相似文献
57.
58.
Ranjan K. Mohanta Kamal K. Singhal Amrish K. Tyagi Y. S. Rajput Shiv Prasad 《Tropical animal health and production》2010,42(3):431-438
The effects of feeding transgenic (Bt) whole cottonseed (WCS) were studied in lactating cows. Twenty multiparous crossbred
cows (Karan Swiss × Karan Fries) in early lactation were given a concentrate mixture containing 40% crushed delinted non-transgenic
(non-Bt) WCS, 2 kg wheat straw and green fodder ad lib for a 15-day adaptation period. Thereafter, the cows were divided in two similar groups of 10 each on the basis of milk yield,
body weight (BW) and date of calving. The non-Bt control group continued on same ration, while for the Bt group the non-Bt
WCS was replaced by transgenic WCS, in a feeding trial of four weeks. The diets provided a minimum of 2 kg cottonseed/cow/d.
Mean DMI/100 kg BW and milk yield of non-Bt and Bt groups was 3.48 and 3.45 kg and 11.4 and 12.0 kg/d, respectively. Intake
of nutrients, digestibility, milk production and body condition score (BCS) did not differ between the groups (P > 0.05),
but BW gain was higher (P < 0.05) in the Bt group than the non-Bt group, probably as a result of hoof problem in two cows
of non-Bt group, which when compared excluding two animals from each group did not differ significantly (P > 0.05). Transgenic
protein (Cry1C) was not detected in the weekly milk samples or in blood plasma at the end of the experiment, showing that
delinted WCS containing Cry1C protein can safely be fed to lactating cows. 相似文献
59.
60.
Sanjay Kumar Gupta Asim Kumar Pal Narottam Prasad Sahu Neelam Saharan Sagar Charan Mandal Chandra Prakash Mohammed Shahbaz Akhtar Ashisa Kumar Prusty 《Aquaculture Research》2014,45(5):893-906
A 45‐day feeding trial was conducted to study the stress ameliorating and immunomodulatory role of microbial levan in Cyprinus carpio fry exposed to sublethal dose (1/10th LC50) of fipronil [(±)‐5‐amino‐1‐(2,6‐dichloro‐α,α,α‐trifluoro‐p‐tolyl)‐4‐trifluoromethylsulfinylpyrazole‐3‐carbonitrile]. Two hundred and twenty‐five fry were randomly distributed in five treatments in triplicates. Four purified diets were prepared with graded levels of microbial levan. Five different treatment groups were levan control L0P0 (basalfeed + 0% levan without exposure to pesticide); pesticide control L0P1 (basalfeed + 0% levan with exposure to pesticide); L0.25P1 (basalfeed + 0.25% levan with exposure to pesticide); L0.50P1 (basalfeed + 0.50% levan with exposure to pesticide) and L0.75P1 (basalfeed + 0.75% levan with exposure to pesticide). Lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and fructose‐1,6‐diphosphatase (FDPase) activites were significantly (P < 0.05) increased, whereas alkaline phosphatase (ALP), adenosine triphosphatase (ATPase) and acetyl choline esterase (AchE) activities were significantly (P < 0.05) reduced in higher levan‐fed groups. RBC, haemoglobin and WBC counts were significantly (P < 0.05) increased in the levan‐fed groups. Similar trends were also observed for the total serum protein, globulin, NBT and lysozyme activities. Blood glucose and serum cortisol exhibited a third order polynomial relationship with increasing level of dietary levan. Overall result showed stress ameliorating, immunostimulating and protective role of microbial levan against fipronil‐induced stress in C. carpio fry at 0.75% level of dietary levan supplementation. 相似文献