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211.
Fish meal replacement by soy protein from soymilk in the diets of red sea bream (Pagrus major) 下载免费PDF全文
A. Biswas H. Araki T. Sakata T. Nakamori K. Kato K. Takii 《Aquaculture Nutrition》2017,23(6):1379-1389
Six isoenergetic diets were formulated as follows: fish meal (FM) 700 g kg–1 (control, C), FM 300 g kg–1 + soy protein concentrate 300 g kg–1 (SPC), FM 300 g kg–1 + enzyme‐treated SPC 300 g kg–1 (ESC), FM 170 g kg–1 + soy protein isolate 300 g kg–1 (SPI), FM 160 g kg–1 + enzyme‐treated SPI 300 g kg–1 (ESI) and FM 150 g kg–1 + conglycinin 300 g kg–1(CG). Forty fish (3.9 g) were randomly distributed into each of eighteen 300‐L tanks, fed twice daily until satiation for 8 weeks. The final body weight, specific growth rate and condition factor did not show significant differences among the fish fed with diets C, SPC, ESC and ESI (p > .05). The survival was significantly lower in fish fed with diets SPI and CG. Feed efficiency was significantly higher in fish fed with diets SPC and C than in fish fed with other diets (p < .05). There were no significant differences in nutrients retention efficiencies in fish fed with diets C, SPC, ESC and ESI. A significantly higher phosphorus retention efficiency in fish fed with soymilk protein diets resulted in lower phosphorus discharge to the environment (p < .05). These results suggest that the soymilk proteins can comfortably replace 570–770 g FM kg–1 diet of red sea bream juvenile, which will ensure significant ecological benefits through reducing phosphorus load to the environment. 相似文献
212.
Partha Sarathi Ghorai Sunanda Biswas Tapan Jyoti Purakayastha Nayan Ahmed Tapas Kumar Das Radha Prasanna Bharat Hanamant Gawade Kallol Bhattacharyya Kanchan Sinha Priya Singh Sujit Das 《Soil Use and Management》2023,39(1):503-520
Deterioration of soil quality under resource-intensive modern agriculture in the face of global climate change poses a huge risk to food security. Because of the complex nature, estimators of soil quality often rely upon a limited set of soil attributes, along with statistical data reduction techniques, for developing quality indices, whilst overlooking biological aspects and regional climatic variability. This study screened the most suitable soil quality indexing approaches for a rice-oilseed-based cropping system in the lower Indo-Gangetic plains (IGP). For this, surface soil samples (0–15 cm) were collected from an ongoing long-term fertilizer experiment with a rice-mustard-sesame cropping system in the IGP. The following treatments were assessed for their effect on soil quality: T1-control, T2-NPK (recommended NPK doses), T3-NPKG (NPK + in situ green manuring), T4-NPKGB (NPK + in situ green manuring + biofertilizer) and T5-NPKF (NPK + farm yard manure FYM). We found that total organic carbon (TOC), β-glucosidase, CaCl2 extractable S, alkaline KMnO4 oxidizable N, activity of urease, amidase enzyme and mean weight diameter (MWD) were sensitive key indicators of soil quality. The NPKF treatment maintained the highest soil quality status (0.80–0.91), both under productivity and environmental protection goals, owing to the availability of decomposable carbon. Regression analysis showed a better agreement of equivalent rice yield with expert opinion (EO; R2 = 0.89) than principal component analysis (PCA; R2 = 0.76). Finally, we found that the expert opinion approach with the nonlinear scoring function was the best tool for soil quality assessment of the region. 相似文献