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991.
Mohammad Nakib Dad Khan Takao Yoshimatsu Alok Kalla Toshiyoshi Araki Shuichi Sakamoto 《Fisheries Science》2008,74(2):397-404
ABSTRACT: A 56-day feeding trial was conducted to evaluate the effects of Porphyra spheroplasts (PS) as a feed additive on growth, carcass composition and feed utilization of black sea bream. Four experimental diets with or without PS (0, 1, 3, 5% inclusion level) were formulated to determine the proper incorporation level for best growth and utilization using white fishmeal as the principal protein source. Three replicate groups of fish averaging 1.28 ± 0.05 g (mean ± SD) were maintained in flow-through thermo-controlled sea water (32–34 psu, 25°C) aquaria (100 L) under the laboratory conditions (L12 : D12) and fed three times a day at 09:00, 13:00 and 17:00 hours by hand at approximately 3% body weight on each diet. The rearing trial revealed that growth performance (in terms of weight gain, specific growth rate) are almost the same level in all the dietary groups, nevertheless the survival, nutrient utilizations and retentions (feed efficiency, protein efficiency ratio, protein retention rate, lipid retention rate) were significantly higher ( P < 0.05) in a group fed on the diet containing 3% spheroplasts. Further, the fish fed on the diet containing PS had significantly higher ( P < 0.05) crude lipid level in their dorsal muscles and viscera. The fish fed a PS-based diet showed higher level of eicosapentaenoic acid and docosahexaenoic acid (DHA) in viscera and DHA in dorsal muscles. The results obtained in this feeding trial suggest that the optimum dietary PS supplementation level up to 3% for black sea bream can be considered as improved consequence on growth performance, nutrient utilization or body composition were noticed. 相似文献
992.
Noorullah Khan Farrukh Siyar Hamid Muhammad Abbas Khan Sarfraz Ahmad Sonia Sumreen Imtiaz Ahmed 《Soil Science and Plant Nutrition》2013,59(6):774-781
The present research was conducted to explore the impact of alternative organic amendments on physicochemical properties of soil and their critical value for kiwi seedlings growth. The experiment was laid out in completely randomized design with 3 replications and 20 seedlings per replication. The highest pH (8.0) was recorded in T3 (compost + silt) and the highest electrical conductivity (EC) of 5.91 dS/m, organic matter (24.11%), organic carbon (13.99%), organic nitrogen (1.51%) were recorded in T8 (compost + peat moss (PM) + leaf manure) and the highest soil porosity (SP) (45.95%) and lowest bulk density (0.67) were recorded in T4 (PM + garden soil (GS)). EC higher than 1.99 and SP (45.95%) were found critical and adversely affected seedling survival. The highest plant height (103 and 93 cm), number of leaves (23 and 20), number of first-order lateral roots (NFLRM) (9 and 8.5), whole seedling fresh mass (75 and 72 g), fresh root mass (FRM) (35 and 35 g), shoot fresh mass (46 and 40 g), root collar diameter (RCD) (13 and 12 mm), and shoot diameter (10 and 9 mm) were recorded in T5 (compost + GS) and T7 (compost + PM + GS). Strong and positive correlations were observed among NFLRP, RFM, and RCD (R2 = 0.89 and 0.96) and all the above-ground seedling traits (R2 = 0.86–0.98). It is concluded that compost is a good soil amendment for producing good quality graftable kiwi seedlings and evaluation of seedling root system architecture could be used to predict the potential and success of seedlings in the field. 相似文献
993.
Salah MA Bedir E Toyang NJ Khan IA Harries MD Wedge DE 《Journal of agricultural and food chemistry》2003,51(26):7607-7610
Hexane and ethyl acetate phases of the methanol extract of Macaranga monandra showed fungal growth inhibition of Colletotrichum acutatum, C. fragariae and C. gloeosporioides, Fusarium oxysporum, Botrytis cinerea, Phomopsis obscurans, and P. viticola. Bioassay-guided fractionation led to the isolation of two active clerodane-type diterpenes that were elucidated by spectroscopic methods (1D-, 2D-NMR, and MS) as kolavenic acid and 2-oxo-kolavenic acid. A 96-well microbioassay revealed that kolavenic acid and 2-oxo-kolavenic acid produced moderate growth inhibition in Phomopsis viticola and Botrytis cinerea. 相似文献
994.
Izabela Michalak Ruchi Tiwari Manish Dhawan Mahmoud Alagawany Mayada R. Farag Khan Sharun Talha Bin Emran Kuldeep Dhama 《The Veterinary quarterly》2022,42(1):48
Natural antioxidants applied as feed additives can improve not only animals’ health and overall performance but also increase their resistance to environmental stress such as heat stress, bad housing conditions, diseases, etc. Marine organisms, for example seaweeds – red, brown, and green macroalgae contain a plethora of biologically active substances, including phenolic compounds, polysaccharides, pigments, vitamins, micro- and macroelements, and proteins known for their antioxidant activity, which can help in the maintenance of appropriate redox status in animals and show pleiotropic effects for enhancing good health, and productivity. The dysregulated production of free radicals is a marked characteristic of several clinical conditions, and antioxidant machinery plays a pivotal role in scavenging the excessive free radicals, thereby preventing and treating infections in animals. Supplementation of seaweeds to animal diet can boost antioxidant activity, immunity, and the gut environment. Dietary supplementation of seaweeds can also enhance meat quality due to the deposition of marine-derived antioxidant components in muscles. The use of natural antioxidants in the meat industry is a practical approach to minimize or prevent lipid oxidation. However, overconsumption of seaweeds, especially brown macroalgae, should be avoided because of their high iodine content. An important point to consider when including seaweeds in animal feed is their variable composition which depends on the species, habitat, location, harvest time, growing conditions such as nutrient concentration in water, light intensity, temperature, etc. This review highlights the beneficial applications of seaweeds and their extracted compounds, which have antioxidant properties as feed additives and impact animal health and production. 相似文献
995.
Dietary methionine requirement of fingerling Indian major carp, Cirrhinus mrigala (Hamilton) 总被引:1,自引:0,他引:1
Indian major carp, Cirrhinus mrigala fingerling (3.85 ± 0.50 cm, 0.50 ± 0.02 g) were fed isonitrogenous and isocaloric diets (40% CP, 4.28 kcal g−1, GE) containing casein, gelatin and crystalline amino acids with graded levels of L- methionine (0.50, 0.75, 1.00, 1.25,
1.50 and 2.00 g/ 100 g, dry diet) with 1.00% cystine fixed, to determine its dietary methionine requirement. A feeding trial
was conducted in triplicate for six weeks. Diets were fed twice a day at 0800 and 1600 h at 5% of body weight/day. The ration
size and feeding regime were worked out prior to the start of the feeding trial. Weight gain (158%) and food conversion ratio
(1.45) were significantly (P < 0.05) higher in fish fed diet containing 1.00% methionine with 1.00% cystine fixed. Second
degree polynomial regression analysis of the weight gain data indicated the dietary methionine requirement to be 1.20 g/100
g of dry diet, corresponding to 3.00% of dietary protein. Second degree polynomial regression analysis was also employed to
determine the relationship between food conversion ratio (FCR) and dietary methionine levels which indicated that the best
FCR occurred at approximately 1.20% dietary methionine level. Carcass composition of fish fed diet containing graded levels
of methionine varied significantly (P < 0.05) except carcass ash content which showed insignificant (P > 0.05) differences
among the dietary methionine levels.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
996.
Muhammad Arif Salman Ali Muhammad Ilyas Muhammad Riaz Kashif Akhtar Kawsar Ali Muhammad Adnan Shah Fahad Imran Khan Shahen Shah Haiyan Wang 《Soil Use and Management》2021,37(1):104-119
Biochar amendments offer promising potential to improve soil fertility, soil organic carbon (SOC) and crop yields; however, a limited research has explored these benefits of biochar in the arid and semi‐arid regions. This two‐year field study investigated the effects of Acacia tree biomass‐derived biochar, applied at 0 and 10 t ha?1 rates with farmyard manure (FYM) or poultry manure (PM) and mineral phosphorus (P) fertilizer combinations (100 kg P ha‐1), on maize (Zea mays L.) productivity, P use efficiency (PUE) and farm profitability. The application of biochar with organic–inorganic P fertilizers significantly increased soil P and SOC contents than the sole organic or inorganic P fertilizers. Addition of biochar and PM as 100% P source resulted in the highest soil P (104% increase over control) and SOC contents (203% higher than control). However, maize productivity and PUE were significantly higher under balanced P fertilizer (50% organic + 50% mineral fertilizer) with biochar and the increase was 110%, 94% and 170% than 100%‐FYM, 100%‐PM and 100% mineral fertilizer, respectively. Maize productivity and yield correlated significantly positively with soil P and SOC contents These positive effects were possibly due to the ability of biochar to improve soil properties, P availability from organic–inorganic fertilizers and SOC which resulted in higher PUE and maize productivity. Despite the significant positive relationship of PUE with net economic returns, biochar incorporation with PM and mineral fertilizer combination was economically profitable, whereas FYM along biochar was not profitable due to short duration of the field experiments. 相似文献
997.
Continuous rise in the atmospheric CO2 concentration upshots the genesis of cataclysmic planetary problems such as global warming and climate change. Another critical issue which is environmentally challenging is land degradation. When productive land is poorly managed, it turns to marginal land. And further degradation of marginal land ends up to being unproductive land. On the Contrary, considerable part of depleted soil C pool can be restored through the adoption of conservation agricultural practices, unproductive land could be converted to marginal land and by its further restoration, into productive land. Aromatic plants can sustain various adverse conditions prevailing on the marginal lands. Aromatic plants require low input but the output is quite high due to the production of highvalue essential oil. The pivotal perspective of utilization of marginal lands of India for the production of aromatic plants would explore factors such as land availability, aromatic plants adaptability, C sequestration potential and economic feasibility. India is the largest exporter of essential oils and produces huge amount of aromatic spent residues, which could be converted into several valueadded products. Proficient recycle of distillation waste of aromatic plants in marginal lands will aid to sequester C in soil and enhance the biomass yield. Improvement in the livelihood of farmers especially in developing nations through rise in production and income diversification would encourage farmers to reclaim their marginal lands and accelerate their transition to aromatically cultivable lands. 相似文献
998.
Waqas–ud–Din Khan Tariq Aziz Imran Hussain Pia Muhammad Adnan Ramzani Thomas G. Reichenauer 《Archives of Agronomy and Soil Science》2017,63(5):599-611
Soil salinity imposes an unprecedented risk to the soil fertility and availability of plant nutrients. The present proposal is designed to address the effect of salt stress on photosynthetic apparatus of maize including chlorophyll a fluorescence and how silicon nutrition helps to overcome this issue. In a sand culture experiment, two maize cultivars were sown in small pots with two levels of silicon (0 and 2 mM H2SiO3) and two levels of salinity stress (0 and 60 mM NaCl). Salinity stress reduced dry matter yield and potassium (K) concentration in both maize cultivars and also induced inefficient working of photosynthetic apparatus including photochemical efficiency of photosystem II. Silicon addition alleviated NaCl stress on maize crop by improving the dry matter yield and water use efficiency (WUE). It decreased shoot Na concentration by increasing root and shoot K concentration of maize plants. It enhanced maximum quantum yield of primary photochemistry which leads to smooth electron transport chain. It also significantly enhanced shoot silicon concentration and has a significant positive correlation with WUE. Therefore, silicon-treated maize plants have better chance to survive under salt stress conditions as their photosynthetic apparatus is working far better than non-silicon-treated plants. 相似文献
999.
Xu Xiaoli Mao Xiali Van Zwieten Lukas Niazi Nabeel Khan Lu Kouping Bolan Nanthi S. Wang Hailong 《Journal of Soils and Sediments》2020,20(11):3921-3930
Journal of Soils and Sediments - The residual phosphorus (P) in Hedley’s sequential fractionation procedure is considered to be a relatively stable soil P pool and unavailable for plant... 相似文献
1000.
Dietary phosphorus requirement of fingerling Labeo rohita (6.1 ± 0.13 cm; 1.88 ± 0.05 g) was quantified by feeding seven isonitrogenous (350 g/kg crude protein) and isocaloric (16.72 kJ/g gross energy) purified diets with different levels of phosphorus as 3.5 (basal diet), 4.6, 5.7, 6.5, 7.8, 8.9, and 10.1 g/kg. Triplicate groups of fish were fed at 0800, 1200, and 1600 h to apparent satiation for 8 wk. Live weight gain (LWG; 494.68%), specific growth rate (3.18%/d), feed conversion ratio (1.54), feed efficiency (0.65), protein gain (PG; 1.26 g/fish), protein efficiency ratio (1.86), and phosphorus utilization efficiency (98.78%) improved significantly (P < 0.05), with increasing dietary phosphorus level up to 6.5 g/kg. However, phosphorus contents of vertebrae and scale increased significantly up to 7.8 g/kg. Dietary phosphorus levels significantly affected serum phosphorus concentration and alkaline phosphatase activity. Broken‐line analysis based on LWG; PG; and whole‐body, vertebrae, and scale phosphorus against dietary phosphorus indicated the optimal phosphorus requirement of fingerling L. rohita at 6.56, 6.58, 6.56, 8.02, and 8.44 g/kg diet, respectively. In order to restrict superfluous phosphorus in the diet, inclusion of 6.56 g/kg phosphorus is recommended for optimal growth of fingerling L. rohita. 相似文献