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131.
Siddartha Purkayastha Sanjay Sarma Wazir Singh Lakra S. Gupta S. P. Biswas 《Journal Of Applied Aquaculture》2013,25(1):42-48
The Pabdah catfish, Ompok pabda, was successfully spawned with the synthetic hormone Ovatide at two different doses (0.4 and 0.6 ml/kg of body weight of female). The latency period was 9–10 h at 0.6 ml compared to 10–12 h at 0.4 ml kg?1 of body weight. All the females spawned successfully. Average rate of fertilization (75.5 %) and hatching (60.5%) was higher with a dose of 0.6 ml kg?1, while lower fertilization (65.1%) and hatching rate (45%) were observed at 0.3 ml kg?1 of body weight. Fecundity ranged from 80–130 eggs gm?1 body weight of female. Eggs hatched between 12–14 h after spawning at a water temperature 28°–32°C. The mean egg diameter was 0.95 ± 0.15 mm. 相似文献
132.
1. The major objective of this study was to examine the influence of 24-h storage of semen at low temperature on semen characteristics and fertilising ability of spermatozoa in two native breeds (Kadaknath-KN, Aseel Peela-AP) and White Leghorn (WL) chicken. 2. Various physical and biochemical properties of freshly ejaculated semen of KN and AP were investigated. Fertility was examined in freshly-ejaculated as well as 24-h-stored (3°C) semen diluted (1:3) with Beltsville Poultry Semen Extender. 3. No significant difference was observed in sperm motility among the different breeds whereas live counts were higher in WL than the native breeds. Body weight, semen volume and sperm concentration were highest in AP, followed by KN and WL. A similar trend was observed in the percentage of dead and morphologically-abnormal spermatozoa. 4. The activity of acid and alkaline phosphatase in seminal plasma were higher in WL than KN, whereas the opposite trend was recorded for glutamic oxaloacetic and pyruvic transaminases. The cholesterol content of semen was highest in AP, followed by KN and WL. Cholesterol was much lower in seminal plasma compared with whole semen but there were no differences between breeds. Mean values of the methylene blue reduction time test were higher in WL than in the native breeds. 5. Fertility and hatchability, using freshly-diluted semen, were poorer in the native breeds than in WL. The pattern of fertility deteriorated further, especially in native fowls, when the birds were inseminated with 24-h-stored semen. 6. In conclusion, variation in physical and biochemical characteristics of semen in native breeds compared to WL correlated with poor fertility after short-term storage of semen. 相似文献
133.
Muneshwar Singh Samaresh Kundu Ashis K. Biswas Jayanta K. Saha Awadhesh K. Tripathi Chuni L. Acharya 《植物养料与土壤学杂志》2004,167(5):577-583
A computational exercise was undertaken to quantify the percent N derived from atmosphere %Ndfa) in soybean and consequent N benefit from biological N2‐fixation process annually accrued to the soil by the soybean crop using average annual N‐input/‐output balance sheet from a 7 yr old soybean‐wheat continuous rotational experiment on a Typic Haplustert. The experiment was conducted with 16 treatments comprised of combinations of four annual rates of farmyard manure (FYM ? 0, 4, 8, and 16 t ha–1) and four annual rates of fertilizer N (? 0, 72.5, 145, and 230 kg N ha–1) applications. The estimated N contributed through residual biomass of soybean (RBNS) consisting of leaf fall, root, nodules, and rhizodeposition varied in the ranges of 7.02–16.94, 11.65–28.83, 3.31–8.91, and 11.3–23.8 kg N ha–1 yr–1, respectively. A linear relationship was observed between RBNS and harvested biomass N (HBNS) of soybean in the form of RBNS = 0.461 × HBNS – 20.67 (r = 0.989, P < 0.01), indicating that for each 100 kg N assimilated by the harvested biomass of soybean, 25.4 kg N was added to the soil through residual biomass. The Ndfa values ranged between 13% and 81% depending upon the annual rates of application of fertilizer N and FYM. As per the main effects, the %Ndfa declined from 76.4 to 26.0 with the increase in annual fertilizer‐N application from 0 to 230 kg N ha–1, whereas %Ndfa increased from 40.8 to 65.8 with the increase in FYM rates from 0 to 16 t ha–1, respectively. The N benefit from biological N2 fixation accrued to the soil through residual biomass of soybean ranged from 7.6 to 53.7 kg N ha–1 yr–1. The treatments having %Ndfa values higher than 78 showed considerable annual contribution of N from N2 fixation to the soil which were sufficient enough to offset the quantity of N removed from the soil (i.e., native soil N / FYM‐N / fertilizer‐N) with harvested biomass of soybean. 相似文献
134.
Biswas Md. Jamil Hossain Mainali Bishwo Inskeep Jess R. Gaire Sushil K. Cross Dominic Stringer Lloyd D. Taylor Phillip W. Rempoulakis Polychronis 《Journal of pest science》2022,95(1):291-301
Journal of Pest Science - Queensland fruit fly (Q-fly), Bactrocera tryoni (Froggatt), is a significant pest of horticultural crops in Australia. The sterile insect technique (SIT) is currently... 相似文献
135.
Direct observation of percolation in a manganite thin film 总被引:1,自引:0,他引:1
Upon cooling, the isolated ferromagnetic domains in thin films of La0.33Pr0.34Ca0.33MnO3 start to grow and merge at the metal-insulator transition temperature TP1, leading to a steep drop in resistivity, and continue to grow far below TP1. In contrast, upon warming, the ferromagnetic domain size remains unchanged until near the transition temperature. The jump in the resistivity results from the decrease in the average magnetization. The ferromagnetic domains almost disappear at a temperature TP2 higher than TP1, showing a local magnetic hysteresis in agreement with the resistivity hysteresis. Even well above TP2, some ferromagnetic domains with higher transition temperatures are observed, indicating magnetic inhomogeneity. These results may shed more light on the origin of the magnetoresistance in these materials. 相似文献
136.
Virulence gene and antibiotic resistance profile of Shiga-toxin-producing Escherichia coli prevalent in captive yaks (Poephagus grunniens) 总被引:2,自引:0,他引:2
137.
Himel Barua Paritosh Kumar Biswas Kaisar Ali Talukder Katharina E.P. Olsen Jens Peter Christensen 《Veterinary microbiology》2014,168(2-4):372-380
We investigated Salmonella enterica isolates from human clinical cases of gastroenteritis to determine the distribution of non-typhoidal Salmonella serovars in the human population, and compared them to isolates originating from poultry by serotyping, phage typing, plasmid profiling, pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) to evaluate the potential role of poultry in human non-typhoidal salmonellosis in Bangladesh. Nine different serovars were identified among the human isolates of which Salmonella Paratyphi B var Java (S. Java), S. Kentucky, S. Enteritidis, S. Virchow and S. Weltevreden also were commonly isolated from poultry. The poultry isolates belonging to S. Java, S. Kentucky and S. Enteritidis were indistinguishable from human isolates or genetically closely related, based on PFGE profiles and MLST. S. Kentucky clone ST198 and S. Java clone ST43 both well-known cause of human infections were also isolated from poultry. 相似文献
138.
Angshuman Biswas Mitali Pramanik Samita Kundu Sumedha Roy Jhuma De Arun Kumar Ray 《Fish physiology and biochemistry》2006,32(1):73-81
Triploid Heteropneustes fossilis (Bloch) showed sterility and higher growth potential than the normal diploid fish. Activities of some metabolic enzymes such
as cytosolic NADP-malate dehydrogenase (NADP-MDH), mitochondrial NAD-malate dehydrogenase (NAD-MDH) and glutamate pyruvate
transaminase (GPT) were evaluated in liver, brain and kidney along with glucose-6-phosphate dehydrogenase (G-6-P D) in ovary
of female triploid catfish. Activities of these enzymes showed distinct seasonal periodicity, mostly with highest activities
in prespawning and spawning periods, in both diploid and triploid catfish but differed in magnitude. In triploid liver, GPT
showed higher activity than the diploid counterpart in prespawning and spawning periods. On the contrary, mitochondrial NAD-MDH
and cytosolic NADP-MDH in this organ showed a consistent lower activity than the diploid in all stages or in some stages of
reproductive cycle respectively. Interestingly, none of the enzymes in brain and kidney of triploid female catfish showed
significant changes in comparison to the diploid counterpart. The triploid ovary maintained a significantly lower level of
G-6-P D activity throughout the resting, preparatory and pre-spawning periods compared to the diploid ovary. Lower level of
malic enzymes (NAD-MDH and NADP-MDH) in liver and G-6-P D in ovary are in close synchrony with lower level of estradiol-17β
in plasma of female triploids as found in earlier study. 相似文献
139.
J.K. Biswas 《Aquaculture (Amsterdam, Netherlands)》2006,261(3):952-959
Advanced fry of common carp (1.6 ± 0.2 g) were reared in experimental outdoor tanks (4500 l; 3 × 1.5 × 1 m) for 312 or 151 days under six stocking conditions of 8, 13, 16, 32, 48 and 64 fish per tank for ascertaining the threshold and critical levels of ammonium and, hence, to recommend the optimum stocking density of common carp for culture under rearing stage conditions. The samples of water were monitored from each tank at regular intervals for water quality parameters as well as for ammonium concentrations. Fishes were harvested at the end of the experiment. The results revealed a significant decrease in fish growth as stocking density increased. Absence of mortality and favorable growth resulted in maximum fish biomass at the stocking density of 16 fish/tank, but the heavy mortality and stunted growth caused the poor total fish biomass in the highest stocking density employed. The interactions between ammonium and fish growth were expressed at three different concentration levels of ammonium: (a) favorable concentration range (0.262-0.294 mg l− 1), (b) growth inhibiting concentration range (0.313-0.322 mg l− 1) and (c) lethal concentration range (0.323-0.422 mg l− 1). The ambient ammonium concentrations of 0.313 mg l− 1 (or equivalent ammonia concentration of 0.0342 mg l− 1) and 0.323 mg l− 1 (or equivalent ammonia concentration of 0.043 mg l− 1), observed for stocking density ranging from 17 to 19 fish per tank, were considered to be the threshold and critical levels of ammonium that caused growth inhibition and mortality of fish. Fish mortality was higher when the ratio of DO to ammonium remained quite low (< 15), but no mortality occurred with higher ratio. Considering the economic viability of the production system, this appears that the optimum fish stocking density would be around SD 16 (equivalent to 210 g m− 3). 相似文献
140.
Merih Otker Uslu Mohammad Feisal Rahman Saad Y. Jasim Ernest K. Yanful Nihar Biswas 《Water, air, and soil pollution》2012,223(6):3173-3180
The reactivity of selected compounds in Lake Huron water was evaluated during ozone/hydrogen peroxide-based advanced oxidation process (AOP) and conventional treatment (coagulation?Csedimentation?Cfiltration). Elimination of these compounds via advanced oxidation and conventional treatment processes were strongly related to their molecular structures. Overall removal of target compounds was quite similar in effluents from both the AOP and the combined treatment process (AOP?+?conventional) with the exception of fluoxetine. Reaction rate constants for the decomposition of the target compounds were substantially higher during AOP compared to conventional treatment alone. 相似文献