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101.
Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants
Background
Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganoderma sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed.Results
Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO3 (1.0), and MgSO4 (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained.Conclusions
The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods. 相似文献102.
Effect of sub-lethal nitrite on selected haematological parameters in fingerling Catla catla (Hamilton) 总被引:1,自引:0,他引:1
Pratap Chandra Das Subanna Ayyappan Joy Krushna Jena & Basanta Kumar Das 《Aquaculture Research》2004,35(9):874-880
A sub‐lethal nitrite toxicity trial was conducted using static conditions for a period of 96 h with fingerlings of Catla catla (21.4±3.6 g). Fingerlings were exposed to five concentrations of nitrite, that is, 1, 2, 4, 8 and 10.4 mg L?1 and a nitrite‐free control to study changes in haematological parameters. Nitrite caused an increase in immature erythrocyte population (7–24%) in lower concentrations (0–4 mg L?1) at 6 h while they were absent in higher concentrations. The total erythrocyte count was reduced at 6 h followed by an increase at 12 h with further reduction up to 96 h in all concentrations of nitrite. The 96‐h exposure resulted in 21.2–31.8% reduction in erythrocyte population in 1–10.4 mg L?1 nitrite. The haemoglobin content decreased progressively with increasing nitrite concentrations as well as exposure periods. Total leukocyte count decreased initially at 6 h in all treatments followed by an increase after 12 h, signifying development of a protective response of the body to nitrite stress. Blood glucose decreased initially up to 24 h followed by an increase through 96 h. Serum protein level decreased continuously with increasing exposure period. The study revealed that exposure to nitrite caused changes in almost all the haematological parameters in the fingerlings depending on the concentration as well as exposure period. Nitrite being one of the important inorganic nutrients often recorded at higher levels in intensively cultured ponds, the present study highlights its adverse impact on fish and stressed the need for the management of this nutrient in culture ponds. 相似文献
103.
Kumari Madhu Kumar Vikas Kaur Ramandeep Kumar Satish Sharma Rakesh 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):241-249
Plant Foods for Human Nutrition - Ficus geniculata (FG) is one of the underutilized fig species in India and throughout the world. However, the different parts of the plant have numerous... 相似文献
104.
105.
106.
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
107.
Nitrogen (N) supply is the major limiting nutrient in most reclamation schemes. In reclaimed mine soil (RMS), examining the N dynamics can be especially informative for understanding constraints on recovery that restrict revegetation success. Scholarly studies worldwide have focused on exogenous N incorporation to alleviate N shortages in the agriculture, and forestry sectors. Currently, growing concerns for the negative consequences of mining have highlighted N deficiency as one of the most significantly identified abiotic limits. Only a few researchers have focused on the N transformation mechanisms in drastically altered mine soils. The review comprises the last 10 years’ research on mine reclamation approaches using legume and non-legume plant communities. Also the capacity of different amendments to alleviate N shortages in mine soils is emphasized. The major findings of the present review suggest: (i) Revegetation using legume and non-legume species is a self-sustaining and economical alternative to mineral N fertilizer application; however, they cannot fully activate the biological N cycle in RMS. (ii) A more biological amendment-assisted revegetation would enhance the key concepts of “soil-biomass N balance” and would be ideal for N recovery in imbalanced mine soil. Altogether, grass-legume seeding offers a potentially valuable mine reclamation tool for managing N and addressing the challenges of sustainable development. 相似文献
108.
Previous studies have indicated that the price premium charged for hybrid catfish fingerlings may be a significant factor in the adoption and profitability of hybrid catfish production. An enterprise budgeting simulation analysis was developed to compare costs, risk, and effect of hybrid fingerling costs. Feed, fingerling, and total costs ($/ha and $/kg) were highest for hybrid catfish production, intermediate for NWAC‐103, and lowest for normal channel catfish production. Net returns were highest for hybrid catfish production, but breakeven prices were also highest. Risk analysis showed that downside risk (risk of losing money) was higher for hybrid production for all farm sizes. Risk‐averse farmers would not select hybrid catfish at the mean fingerling values used in the analysis. However, at hybrid fingerling prices less than $0.0081/cm, hybrid catfish production was superior in profitability and breakeven cost of production. Thus, for hybrid catfish production to be preferred economically to normal channel catfish, the price premium for hybrid catfish fingerlings can be no more than 84% ($0.0037/cm) above that of normal channel catfish fingerlings and 57% ($0.0025/cm) above that of NWAC‐103 fingerling prices. 相似文献
109.
Abstract Rice is mostly transplanted under puddled low land soil conditions in India, where Zinc (Zn) deficiency is a common problem. The objective of this study was to find out the efficacy of split application of Zn on growth and yield of rice in an inceptisol. The split application of Zn as ZnSO4 · 7H2O performed better than its single basal application, while the split application of Zn-EDTA did not show any significant difference on yield and yield components of rice over its single basal application. Zn-EDTA was found to be better for growth and yield of rice among the two sources of Zn. The soil application of Zn at 1.0 kg ha?1 as Zn-EDTA (T7) recorded highest grain yield of 5.42 t ha?1, filled grain percentage of 90.2%, 1000-grain weight of 25.41 g and number of panicles m?2 of 452. The Zn content of grain and straw were found to be maximum in the treatment T7 i.e. 38.19 and 18.27 mg kg?1, respectively. Linear regression studies indicated that grain yield of rice is significantly influenced by Zn content of grain, Zn content of straw and DTPA extractable Zn content of soil at the level of 95.96, 96.74 and 95.57%, respectively. 相似文献
110.
Entomophaga aulicae (Hoffman in Bail) Batko (Zygomycotina: Entomophthorales) was found to cause epizootics in Spilarctia obliqua (Walker) (Arctiidae: Lepidoptera), a polyphagous pest in Manipur, India. Infected caterpillars climbed to elevated positions
on plants where they hung upside down, attached by their abdominal prolegs. Infection levels reached up to 57%. The conidiophores
are simple, conidia are ovoid to pyriform in shape, and the nuclei stained readily in aceto-orcein. Secondary, tertiary conidia
and resting spores were also observed. No rhizoids and cystidia were found. This is the first report of E. aulicae infecting S. obliqua in Manipur. 相似文献