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991.
Chandradevan Machap Simoh Sanimah Mediani Ahmed Ismail Intan Safinar Abas Faridah 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):243-251
Plant Foods for Human Nutrition - Gynura procumbens and Cleome gynandra are two herbs commonly used in Malaysia to treat various ailments and are also consumed as salads (ulam) and vegetables. The... 相似文献
992.
Freshwater prawn farming in Bangladesh: history, present status and future prospects 总被引:1,自引:0,他引:1
Within the overall agro-based economy in Bangladesh, freshwater prawn ( Macrobrachium rosenbergii ) farming is currently one of the most important sectors of the national economy. During the last two decades, its development has attracted considerable attention for its export potential. Freshwater prawn farming offers diverse livelihood opportunities for a large number of rural poor. Although the prospects for prawn farming are positive, it requires some research and development activities for long-term sustainability. This paper provides an overview of freshwater prawn farming in Bangladesh. 相似文献
993.
Muhammad Zohaib Nawaz Raghul Subin Sasidharan Huda Ahmed Alghamdi Hongyue Dang 《Marine drugs》2022,20(2)
Environmental microbes living in communities engage in complex interspecies interactions that are challenging to decipher. Nevertheless, the interactions provide the basis for shaping community structure and functioning, which is crucial for ecosystem service. In addition, microbial interactions facilitate specific adaptation and ecological evolution processes particularly essential for microbial communities dwelling in resource-limiting habitats, such as the deep oceans. Recent technological and knowledge advancements provide an opportunity for the study of interactions within complex microbial communities, such as those inhabiting deep-sea waters and sediments. The microbial interaction studies provide insights into developing new strategies for biotechnical applications. For example, cooperative microbial interactions drive the degradation of complex organic matter such as chitins and celluloses. Such microbiologically-driven biogeochemical processes stimulate creative designs in many applied sciences. Understanding the interaction processes and mechanisms provides the basis for the development of synthetic communities and consequently the achievement of specific community functions. Microbial community engineering has many application potentials, including the production of novel antibiotics, biofuels, and other valuable chemicals and biomaterials. It can also be developed into biotechniques for waste processing and environmental contaminant bioremediation. This review summarizes our current understanding of the microbial interaction mechanisms and emerging techniques for inferring interactions in deep-sea microbial communities, aiding in future biotechnological and therapeutic applications. 相似文献
994.
Faruq Ahmed Susumu Segawa Masashi Yokota Seiichi Watanabe 《Aquaculture (Amsterdam, Netherlands)》2008,279(1-4):160-165
Oxygen consumption and ammonia excretion rates of three abalone species, Haliotis discus discus, H. gigantea, H. madaka and their hybrids were measured at 20 °C by incubating for 3 h under dark and light (N = 9–13 for each species and hybrid). Animals were fasted before and during the experiment and measurements were made first under dark followed by light on the next day. The rates increased with the increase in body weight and were higher under light than dark. On average, H. discus discus had higher oxygen consumption (DD; dark = 0.039, light = 0.04 ml/g/h) than H. gigantea (G; D = 0.033, L = 0.036) and H. madaka (M; D = 0.034, L = 0.035); the hybrids had varied patterns with respect to their parental species [DD × M (D = 0.032, L = 0.038); M × DD (D = 0.03, L = 0.038); G × DD (D = 0.035, L = 0.04) and DD × G (D = 0.03, L = 0.034), mother first]. M (0.261, 0.298 μmol/g/h) had the highest ammonia excretion rate while G (0.162; 0.264) and DD (0.229; 0.232) had the lowest under dark and light, respectively. The hybrids had varied patterns in comparison with their parents (DD × M = 0.247, 0.32;M × DD= 0.177, 0.28; DD × G = 0.249, 0.364 and G × DD = 0.116, 0.155). The O/N ratios under both conditions in all species and hybrids indicated that they had carbohydrate dominated metabolism. Results demonstrated physiological variability among the species and hybrids indicating necessity of different strategies for their management and aquaculture. 相似文献
995.
Dora Zouiten Ines Ben Khemis Ahmed Slaheddin Masmoudi Christine Huelvan Chantal Cahu 《Aquaculture Research》2011,42(11):1723-1736
The quality of development in intensive or mesocosm hatchery‐reared Dicentrarchus labrax larvae was investigated using physiological indicators assessing ontogeny. Larvae were reared in intensive (120 L tanks) and in mesocosm systems (20 m3 enclosures) with the same feeding sequence, excluding the wild zooplankton naturally available in mesocosms. Faster growth was recorded since early development [16 day after hatching (DAH)] in the mesocosm. Maturation of the digestive system also occurred earlier as indicated by the higher amylase secretion ratios, the intestinal maturation index (alkaline phosphatase/leucine–alanine peptidase and aminopeptidase‐N/leucine–alanine peptidase ratios) and the more developed intestinal epithelium at 23 DAH. Nevertheless, the delay in digestive maturation in the intensive system seemed retrieved within few days. In both the groups, the number of vertebrae ranged between 24 and 26, with the dominant class being 25 vertebrae. However, the distributions differed between treatments for meristic characteristics, ossification stages and incidence of malformation types. Loss of a vertebra was more frequent in the intensive system, while the appearance of an additional vertebra was more frequent in the mesocosm. Ossification at 37 DAH was also more advanced in the mesocosm in addition to a lesser rate and severity of skeletal malformations. It is suggested that the early nutritional contribution of mesocosm wild zooplankton, yet at densities of 0.2–0.7 prey mL?1, had key effects on larvae development since the early stages. 相似文献
996.
Madan M. Dey Roehlano M. Briones Mahfuzzudin Ahmed 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1-2):113-139
ABSTRACT Quantitative modeling of fish supply, demand and trade is a useful tool for analyzing recent structural changes, such as the rapid development of aquaculture. Existing models are, however, limited by their use of highly aggregated fish categories and assumed (rather than estimated) elasticities. This paper outlines an estimation strategy and a multiproduct equilibrium model for disaggregated analysis of fish supply, demand, and trade. The model is composed of a producer, consumer and trade core, and is specified to accommodate special features of the fish sector. The estimation and modeling strategy also address common data problems, such as heterogeneity of fish types, diversity of production categories, and so forth. The model has been applied to nine major fish producers in developing Asia. 相似文献
997.
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
998.
999.
Peach fruit fly (PFF), Bactrocera zonata, is one of the most dangerous pests of horticultural crops worldwide. This pest spends part of its life cycle in the soil as pre-pupae and pupae. Therefore, the effects of soil type and soil water content levels (SWCLs) on pupal mortality rates of the PFF were studied in an attempt to use soil moisture as an abiotic management strategy for this pest. The effect of clay, loamy, and sandy soils with SWCL of 0, 10, 25, 50, 75, 90, and 100% of field capacity on three ages of PFF pupae (newly formed, 4- and 7-day-old pupae) were studied. Results demonstrated significant effects of SWCLs on pupal mortality rates of PFF. SWCL was the factor with the most remarkable effect (48.47%), meanwhile soil type had a feeble effect (0.65%). Newly formed pupae were more susceptible to SWCL levels than 7- and 4-day-old pupae. Results suggest that sustaining SWCL near 100% of field capacity significantly (p?=?0.000) suppressed PFF population; therefore it could be an important component of Integrated Pest Management against this insect species. 相似文献
1000.
The aphids Aphis craccivora Koch attack country bean Lablab purpureus L. both in its vegetative and reproductive stages and cause severe damage. To develop an integrated management of aphid powders of black pepper, chili, turmeric, and coriander; oils of mahogany, neem, and eucalyptus; aqueous extracts of neem, basil, and garlic leaves; and water were evaluated in field conditions. The treatments were applied at 7?day intervals and aphid abundance per inflorescence was counted at 24, 48, and 72?h after treatment. All the plant materials reduced aphid abundance and flower infestation, ensuring a higher yield with larger and heavier pods. The neem oil treatment had the lowest abundance of aphid and consequently produced the highest marketable and gross yields. Predatory insects were abundant in the field, but their populations were lower in the treatments than the control. An economic analysis indicated that the highest gross return, net return, adjusted net return, and benefit-cost ratio were obtained from the mahogany oil treatment. The plant materials have insecticidal potential against aphids, and the oils of mahogany and neem showed better performances. 相似文献