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Suchisree Jha ;Palash Mandal ;Phalguni Bhattacharyya ;Amitava Ghosh 《畜牧与生物技术杂志(英文版)》2014,(3):348-356
The mulberry leaves have been considered as a sole food source for silkworm, Bombyx mori (L.). In present work an attempt was made to investigate the role of low molecular weight peptide(s) isolated from mulberry leaves on silkworm rearing. Also we have tried to find out the role of free-radical scavenging activities of isolated peptide(s) on silkworm growth. Larval growth rate was found effective under the influence of peptide(s). Consumption rate of larvae after peptide(s) treatment on mulberry leaves was significantly enhanced over control. High antioxidant activity was found in Low molecular weight peptide(s) which have an effect on silkworm. 相似文献
234.
ABSTRACTRohu (Labeo rohita) is the most popular fish in South Asia. Its farming is often constrained by shortages of seed due to low survival (20%–30%) during nursing. Hypothesizing that probiotics might help, varying doses of two multistrain commercial probiotics were tested at hatchling (days 8–38), fry (days 38–68), and advanced fry (days 68–98) stages. The first probiotics (P1) consisted of Bacillus subtilis, Pediococcus acidilactici, and yeast (Saccharomyces cerevisiae) and the second probiotics (P2) of Bifidobacterium and Lactobacilli plus yeast (Saccharomyces cerevisiae), microalgae (Spirulina sp.), and phytase. Low, medium, and high doses of P1 (1.0, 2.0, and 3.0 g/kg) and P2 (0.5, 1.0, and 2.0 g/kg) were tested, supplementing the control diet, which consisted of mustard oil cake (40%), rice bran (30%), wheat flour (20%), and fish powder (10%). At the hatchling stage results showed that medium and high doses of P1 increased survival by 14.4% and 16.2% respectively over the control. Similarly, medium and high doses of P2 increased survival by 22.1% and 22.3% respectively compared to the control. Survival of hatchlings and fry increased linearly (P < 0.01) with the increase in the doses of P1. The dose of P2 had a quadratic relationship with the survival based on which dose of 1.5 g and 1.7 g/kg feed was found to maximize the survival of hatchlings (72%) and fry (99%) respectively. Regression analysis also showed that maximum specific growth rate (SGR%/day) of fry could be obtained with the estimated dose of 3.3 g/kg diet for P1 and for 1.5 g/kg diet for P2. Therefore, tested probiotics are beneficial during the nursing of Rohu hatchlings and fry or before the age of 68 days but not for nursing afterwards. 相似文献
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Gurusamy Dhandapani Howell Jeffrey L. Chereddy Shankar C. R. R. Mogilicherla Kanakachari Palli Subba Reddy 《Journal of pest science》2021,94(4):1461-1472
Journal of Pest Science - The southern green stink bug, Nezara viridula, is a worldwide pest of many important crops. RNA from N. viridula nymphs and adults was sequenced and assembled into a... 相似文献
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Though it is undoubted that tropical bees are influenced by habitat composition, few studies have investigated the relative importance of both local and landscape-level habitat parameters in supporting large and diverse bee communities. The conservation of native bee communities within agroforestry landscapes is particularly urgent given the importance of pollination services within these systems. In this study, we examined tropical bee communities within a largely deforested shade coffee-growing region in Chiapas, Mexico. We used regression tree modeling to examine the response of bee functional groups to local and landscape-level habitat management. Our models revealed that the most predictive factors for bee abundance and species richness were the number of tree species, the number of tree species in flower, and the canopy cover of the local agroforestry landscape. Solitary bees were most abundant in habitats with high canopy cover, while social bees were most abundant in habitats with greater tree species richness. Cavity-nesting and wood-nesting bee abundance was positively affected by the amount of canopy cover in the farm, while ground-nesting bees were most abundant in habitats with a large number of tree species in flower. Our results demonstrate that across bee sociality groups, nesting guilds, and tribes, the most critical factor impacting native bee communities was within-farm local vegetation management. These results reveal the important role that agroforestry managers can have on biodiversity conservation, and the potential contribution they can make by creating resource-rich agricultural matrices. Specifically, our findings highlight the importance of diverse overstory tree management in supporting native bee communities within tropical agroforestry systems. 相似文献
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B. Vijaya Ramnath S. Rajesh C. Elanchezhian A. Santosh Shankar S. Pithchai Pandian S. Vickneshwaran R. Sundar Rajan 《Fibers and Polymers》2016,17(1):80-87
Nowadays, automotive, packaging and sport equipment industries are using natural fibre based composite materials as they are cheap, abundantly available and having a lot of ecological advantages. The main objective of this paper is to introduce a new concept of fibre twisting and to investigate the effect of twisting and the fibre orientation on the mechanical properties of bio degradable green composites. Here, the composites are fabricated by vacuum assisted compression molding technique in which the problems of hand lay process are eliminated. Here, two fibers namely twisted neem and twisted kenaf are sandwiched between layers of glass fibres to enhance the stiffness and strength of the laminates. Initially, the fibers are alkalized to increase the mechanical properties. The result shows that there is a significant improvement in mechanical properties of composites due to the presence of twisted fibers. It also shows the influence of fiber orientation on mechanical properties. 相似文献
240.
Ramanath M Mridula Joseph K Manissery Perar Keshavanath Kalkuli M Shankar Mudnakudu C Nandeesha & Kothanahally M Rajesh 《Aquaculture Research》2005,36(7):635-642
Sugarcane bagasse (T1), paddy straw (T2) and their mixture (T3) were added to mud‐bottomed, manured cement tanks in triplicate to study the effect on bacterial biofilm production and growth and survival of rohu, Labeo rohita. All tanks were stocked with fingerling rohu at 10 000 ha?1. The total plate count (TPC) of bacteria in water and on substrate did not differ significantly between treatments. The mean phytoplankton and zooplankton density in water was the highest in T2, followed by T3 and T1. The growth of fish was significantly (P<0.05) higher in T2 and T3 compared with T1. Significantly higher RNA values were recorded in T2 and T3 compared with T1. Similarly, T2 and T3 registered higher DNA values than T1. RNA:DNA ratio was higher in T2 compared with T1. However, T3 did not differ significantly from T1 and T2. Both intestinal and hepatopancreatic protease and lipase activity was higher in T1 and T2 compared with T3 and both differ significantly from T1. Intestinal amylase activity was higher in T2 and T3 compared with T1, whereas hepatopancreatic amylase activity was higher in T2 compared with T1 and T3. The results demonstrated that production of L. rohita can be significantly increased by the introduction of biodegradable substrates into culture systems where fertilization is employed. 相似文献