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21.
Hadi D. A. Billah M. Biswas K. F. Rafiqul Islam 《Water, air, and soil pollution》1999,111(1-4):377-384
Precipitation was collected on an event basis from July 1994 to August 1995 at towns around the capital Dhaka of Bangladesh. The major chemical components were determined by atomic absorption spectrophotometry, UV-Visible spectrophotometry and ion selective electrode method. The concentrations of nitrate and sulphate were found to be below the minimum detection limit of 1.0 mg L- 1; the concentrations of Cl-, Na+, K+, Ca+2, Mg+2 and NH4+ ranged from <1.0–3.03, 0.14–1.70, 0.04–0.37, 0.04–1.30, <0.02–0.20 and <0.10–2.33 mg L-1, respectively. The values of pH and conductivity ranged from 4.80–6.74 and 3.3–37.5 μS cm-1, respectively. 相似文献
22.
Amal Biswas Biswajit K. Biswas Junichi Ito Osamu Takaoka Norishige Yagi Syunsuke Itoh Kenji Takii 《Fisheries Science》2011,77(4):615-621
This study was carried out to investigate whether expensive enzyme-treated fish meal (EFM) can be partially replaced by soybean
meal (SM) or enzyme-treated SM (ESM) without compromising the growth of captive-raised Pacific bluefin tuna (PBT) juveniles.
Five fish diets were tested: EFM (control) and EFM in which 10 or 20% of the EFM was replaced with either ESM or SM (ESM10, ESM20, SM10 and SM20, respectively). The respective diets were provided to 28-day-old PBT juveniles (mean body weight approx. 0.38 g) stocked
randomly in 15-m3 tanks (276 juveniles per tank; two tanks per treatment) for 12 days. The final mean body weight of PBT juveniles on diets
EFM, SM10, and SM20 was significantly higher than that of juveniles on diet ESM20. Although daily feeding rate was significantly higher in the ESM and SM groups, feed efficiency (FE) was significantly higher
in the EFM group; there was no significant difference between juveniles fed diets EFM and SM10. Protein and phosphorus retention efficiency were significantly lower in the ESM20, and ESM20 and EFM groups, respectively. Phosphorus discharge was significantly lower in the SM groups. The results demonstrate that
10% SM (11% EFM replacement) can be included in EFM without compromising the growth performance of PBT juveniles. 相似文献
23.
Effects of biofloc under different carbon sources and protein levels on water quality,growth performance and immune responses in black tiger shrimp Penaeus monodon (Fabricius, 1978) 下载免费PDF全文
Sujeet Kumar Panantharayil S Shyne Anand Debasis De Ashutosh D Deo Tapas K Ghoshal Jitendra K Sundaray Alphis G Ponniah Karingalakkandy Poochirian Jithendran Ramalingam Ananda Raja Gouranga Biswas Natarajan Lalitha 《Aquaculture Research》2017,48(3):1168-1182
A 75‐day 2 × 3 factorial experiment was conducted to evaluate the effect of two levels of dietary protein (32 and 40%) and two different carbon sources (rice flour–R and molasses‐M), and without carbohydrate (control–C) in black tiger shrimp Penaeus monodon juveniles (3.37 ± 0.04 g) at 100 nos. m?3 in 100 L fibre reinforced plastic tanks. Biofloc volume and total suspended solid were higher in molasses added groups (32 + M and 40 + M) followed by rice flour (32 + R and 40 + R) and controls (32C and 40C). Molasses and rice flour addition significantly reduced (P < 0.01) the total ammonia–N compared to controls. The highest Vibrio, Bacillus and Lactobacillus counts were recorded in 40 + M, 32 + M and 32 + R respectively. Among the treatments, significantly higher (P < 0.01) final body weight was recorded in 40 + R (8.5 ± 0.3 g), 40 + M (7.8 ± 0.3 g) and 32 + R (7.5 ± 0.4 g) compared to control groups, 32C (6.1 ± 0.3 g), 40C (6.4 ± 0.3 g) and molasses added group, 32 + M (5.7 ± 0.4 g). Rice flour supplementation significantly increased (P < 0.01) the total haemocyte count (×106 cells mL?1) in 32 + R (45.7 ± 3.7) and 40 + R (44.3 ± 3.1) compared to controls, 32C (27.3 ± 3.4) and 40C (25.8 ± 0.9). Similarly, higher superoxide dismutase, catalase, serum protein and glucose were recorded in the rice flour added groups, 40 + R followed by 32 + R. Among the treatments, the highest level of prophenoloxidase (OD 490 nm, 0.3 ± 0.0) and survival after challenge with Vibrio harveyi (55.6%) was observed in 32 + R. The study elucidates that rice flour addition produces optimum level of biofloc with better growth and immune responses compared to molasses and control. Furthermore, rice flour addition at 32% protein level could replace 40% protein feed. 相似文献
24.
25.
Fumiaki Takakuwa Keinosuke Suzuri Takao Horikawa Kunpei Nagahashi Shinichi Yamada Amal Biswas Hideki Tanaka 《Aquaculture Research》2020,51(3):1293-1302
Potato protein concentrate (PPC) is a promising candidate as a fish meal (FM) substitute because it has high protein and essential amino acid content. In the present study, we replaced FM in greater amberjack diets with PPC to investigate the effect on growth and feed utilization. Four isonitrogenous, isolipidic and isocaloric experimental diets were prepared by substituting 0, 20, 40 and 60% of FM protein with PPC (Control, P20, P40 and P60 respectively). The in vitro protein digestibility of protein in PPC was 88.8%, relative to 100% protein in the FM. The in vitro protein digestibility of protein in the experimental diets also decreased with increasing PPC and was lowest at 84.2% in P60. After the 7‐week feeding trial, final body weight, weight gain and thermal growth coefficient tended to decrease with increasing PPC and were significantly lower in P60 than in the control (p < .05). Further, fish fed with diets P40 and P60 showed significantly lower feed conversion and protein efficiency ratios than the control group (p < .05). In conclusion, the results suggest that PPC can replace up to 20% of FM in the diet of greater amberjack without compromising the growth performance or feed efficiency. 相似文献
26.
Phosphorus dynamics and solubilizing microorganisms in acid soils under different land uses of Lesser Himalayas of India 总被引:1,自引:0,他引:1
Ranjan Paul Raj Deo Singh A. K. Patra D. R. Biswas Ranjan Bhattacharyya K. Arunkumar 《Agroforestry Systems》2018,92(2):449-461
Although chemical and some soil physical properties have been studied under different land uses of the Lesser Himalayas of India, very limited information is available on soil biochemical properties. Hence we investigated phosphorus (P) fractions [total P (TP), inorganic P (Pi), organic P (Po), available P, microbial biomass P (MBP)], enzyme activities [dehydrogenase, phosphatases, phytase], phosphate solubilizing bacteria (PSB) and fungi (PSF), and their correlations of acid soils (0–15 and 15–30 cm depths) under different land uses (viz, organic farming, maize–wheat, apple orchard, undisturbed oak forest and uncultivated land of the Indian Himalayas). All land use systems differed significantly for the P fractions, except TP. The highest values for TP, Pi, available P and MBP were found in soils under oak forest and lowest in uncultivated land. However, Po content was highest in apple orchard. The organic farming (organic manures field under garden pea-french bean cropping system for > 10 years) maintained highest activities of dehydrogenase, acid phosphatase and alkaline phosphatase. The highest phytase activity and highest numbers of PSB (99 × 103 g?1 soil) and PSF (30 × 103 g?1 soil) were observed in the rhizosphere soils of oak forest. Significant relationships between soil P fractions and enzyme activities, except alkaline phosphatase, were recorded in surface soil layer. PSB and PSF population were also correlated significantly with P fractions and enzyme activities. This would lead us to understand the level of degradation of P pools due to cultivation over forest system and the suitable management practices needed for soil quality restoration. 相似文献
27.
Embryonic and larval developments of brackish water catfish,Mystus gulio (Hamilton and Buchanan, 1822) induced with human chorionic gonadotropin and consequent larval rearing 下载免费PDF全文
Prem Kumar Gouranga Biswas Tapas Kumar Ghoshal Muniyandi Kailasam Koyadan Kizhakedath Vijayan 《Aquaculture Research》2018,49(7):2466-2476
Mystus gulio, the long whiskers catfish, is a popular food fish and potential candidate species for aquaculture in Sundarban area of India and Bangladesh. Recently, catch of this species has declined due to overfishing and various ecological changes. In the present study, mature fish was induced to spawn in captivity through intramuscular injection of human chorionic gonadotropin at the doses of 10 IU/g to female and 5 IU/g to male. Photomicrographs of all developmental stages of live embryo and larvae were documented with the aid of a light microscope. Results demonstrated that morula, blastula, gastrula and neurula and organogenesis ended at 1:30‐, 3:00‐, 5:30‐, 7:30‐ and 17:15‐hour post‐spawning (hps) respectively. Heartbeat and muscular contraction of embryo commenced at 8:30 and 11.15 hps respectively. Hatching of embryo started after an incubation period of 17:30 hour at an ambient temperature of 29 ± 1°C. The newly hatched larvae measured 2.17 ± 0.29 mm in total length with a yolk volume of 0.165 ± 0.03 mm3 started feeding 36 hr after hatching. The present study, on induced breeding and chronological development of M. gulio embryo, will have significant implications on conservation and seed production for aquaculture. 相似文献
28.
29.
K. Ramesh K. Sammi Reddy I. Rashmi A.K. Biswas 《Communications in Soil Science and Plant Analysis》2016,47(3):369-374
Analysis of differential pore-volume distribution (DPVD) patterns of a commercial Clinoptilolite has been conducted experimentally using an analyzer by measuring the N2 adsorption isotherm. The commercial material was fractionated by sieving through sequential sieves: <125 µ (Z8; fine), 125–250 µ (Z9; medium), and >250 µ (Z10; coarse). The DPVD of the fractions were calculated from the hysteresis loop according to the adsorption and desorption curves of Dollimore-Heal (DH) model. The adsorption cycle had produced dissimilar differential pore volume distribution patterns. For the 10-nm pore width, fine and medium fractions had a maximum pore volume up to 0.0016 cm3/g nm, while the coarse fraction had a little greater value up to 0.002 cm3/g nm. Moreover, the medium fraction had too many hills and valleys in the DPVD. However, the desorption cycle–based DH analysis did not show any marked variation in the DPVD pattern. 相似文献
30.
Biswas PK Barua H Uddin GM Biswas D Ahad A Debnath NC 《Preventive veterinary medicine》2009,88(1):67-71
A serologic survey was undertaken in chickens in smallholdings in Bangladesh for avian influenza A virus (AIV), egg drop syndrome '76 virus (EDS'76V), infectious bronchitis virus (IBV), Newcastle disease virus (NDV) and reovirus (RV) in three phases: January 2002-May 2003, September 2003-August 2004, and August 2005-March 2006. Four hundred thirty-six sera collected in the 2nd phase, 295 in the first phase, 755 in the 1st plus 2nd phases and 295 in the 1st phase were investigated for AIV, EDS'76V, IBV and RV, respectively, using enzyme linked immunosorbent assays. All 854 sera collected in the three phases were screened for NDV using hemagglutination inhibition test. In chickens 20% were seropositive to AIV, 3% to EDS'76V, 74% to IBV, 88% to NDV, and 47% to RV. The seroprevalence in flocks was 23% to AIV, 6% to EDS'76V, 79% to IBV, 89% to NDV and 56% to RV. Twenty-five percent chickens had > or = 10log(2)HI titers to NDV. 相似文献