Studies on lipid nutrition in larvae and juveniles of the indian white prawn penaeus indicus h. milne edwards

Recent studies with prawns indicate that their growth, metamorphosis, maturation and moulting are affected by the typo and level of lipids supplied in the diets. Despite the recognition of the importance of lipids in the diets of prawns there is no information on the essentiality and quantitative lipid requirements of Indian penaeid prawns. Therefore during the present study about 24 laboratory experiments were conducted to determine the essentiality and dietary requirements of total lipids, phoapholipida, fatty acids cholestrol, and to ascertain the nutritional value of natural lipid sources for the larvae, post-larvae tad juveniles of one of the most suitable cultivable species of panaeid prans. All the experiments were conducted in the laboratory following standard procedures, using isonitrogen and approaximately isocaloric purified diets. Changes were made in tha ingridients as required for specific requirements. For the larvae diets of particle size < 37) were fed, For the postlarvae and juveniles pellet feed was given. while data on survival and growth of larvae and pout-larvae 1-10 were recorded, data were collected on the survival, growth, food conversion ratio, protein efficiency ratio and biochemical composition at the body for post-larva 11-25 and juveniles. The influence ot fatty acid pattern of dietary lipid sources on the fatty acids profile of prawns were also studied in the case of juvenile prawns. Analysis of variance andleast significant differences test were employed to determine the significant differences between treatments in the observed parameters with the help of a newlett Packard master computer.

Efficacy of fermented prawn shell waste as a feed ingredient for Indian white prawn, Fenneropenaeus indicus

Prawn shell waste collected from shrimp-processing plants in Cochin, India, was subjected to fermentation using 20 chitinoclastic and proteolytic/non-proteolytic bacterial strains. The products generated were analysed for protein, lipid, total sugars, N-acetyl glucosamine, free amino acids and ash. Shrimp diets were prepared using these 20 fermented products and a control diet using raw prawn shell waste. Feeding experiment was conducted with postlarvae (PL21) of Indian white prawn, Fenneropenaeus indicus for a period of 21 days. Biogrowth parameters such as mean weight gain, feed conversion ratio, specific growth rate and protein efficiency ratio were estimated and the animals were challenged with white spot virus orally via diet. Enhanced growth could be observed in prawns fed F134 and F124, incorporated with the fermentation products generated using Bacillus spp., C134 and C124 respectively. The percentage survival of prawns after 7 days of challenge was found to be highest for groups fed diet F111 incorporated with fermentation product generated using Bacillus sp. These products of bacterial fermentation hold promise as growth enhancers and immunostimulants in aquaculture. KEY WORDS: biogrowth parameters, feed

Marine yeast Candida MCCF 101 as feed supplement in aquaculture: nutritional quality, optimization of large scale production and evaluation of its protective effect on Koi carp from Aeromonas infection

Marine yeast have been regarded as safe and showing a beneficial impact on biotechnological process. It provides better nutritional and dietary values indicating their potential application as feed supplements in aquaculture. Brown et al. (1996) evaluated all the marine yeasts characterised with high protein content, carbohydrate, good amino acid composition and high levels of saturated fats. However, there is paucity of information on marine yeasts as feed supplements and no feed formulation has been found either in literature or in market supplemented with them. This statement supported by Zhenming et al. (2006) reported still a lack of feed composed of single cell protein (SCP) from marine yeasts with high content of protein and other nutrients. Recent research has shown that marine yeasts also have highly potential uses in food, feed, medical and biofuel industries as well as marine biotechnology (Chi et al., 2009; 2010). Sajeevan et al. (2006; 2009a) and Sarlin and Philip (2011) demonstrates that the marine yeasts Candida sake served as a high quality, inexpensive nutrient source and it had proven immunostimulatory properties for cultured shrimps. This strain has been made part of the culture collection of National Centre for Aquatic Animal Health, Cochin University of Science and Technology as Candida MCCF 101. Over the years marine yeasts have been gaining increased attention in animal feed industry due to their nutritional value and immune boosting property.Therefore, the present study was undertaken, and focused on the nutritional quality, optimization of large scale production and evaluation of its protective effect on Koi carp from Aeromonas infection

Single-Feed Dual-Band Circularly Polarised Microstrip Antenna

A novel technique for obtaining dual-hand circular polarization (CP) radiation of a single-feed circular microstrip antenna in proposed and demonstrated. By embedding two pain of arc shaped slots of proper lengths close to the boundary of a circular patch, and protruding one of the arc-shaped slots with a narrow slit, the circular microstrip antenna can perform dual-hand CP radiation using a single probe feed. Details of the antenna design

A Strip-Loaded Feed-Horn Antenna

Design and development of a new feed -horn antenna with low sidelobe levels is reported . The E-walls of this antenna are fabricated with low -loss dielectric substrate , periodicallyloaded with thin conducting strips . The antenna is found to be simulating the radiation characteristics of metallic Corrugated horns . This can be an ideal substitute for metallic Corrugated horns with added advantages like light -weight and low production cost

Single-feed dual-frequency dual-polarized slotted square microstrip antenna

A novel dual frequency dual-polarized square microstrip patch antenna embedded with a slot is presented. The proposed antenna offers tunability of the frequency ratio between the two frequencies by adjusting the slot dimensions. This configuration also provides a size reduction up to -51 and 35% for the two modes as compared to a square micro strip patch antenna

Wide Band Rectangular Microstrip Antenna using Symmetric T-shaped Feed

Bandwidth enhancement of a rectangular microstrip antenna using a T-shaped microstrip feed is explored in this paper. A 2:1 VSWR impedance bandwidth of 23% is achieved by employing this technique. The far-field patterns are stable across the pass band. The proposed antenna can be used conveniently in broadband communications

A Wideband Rectangular Microstrip Antenna Using an Asymmetric t-shaped Feed

An electromagnetically coupled T-shaped microstrip feed used to enhance the impedance bandwidth of a rectangular microstrip antenna is reported. The proposed antenna offers a 2:1 VSWR bandwidth of -36% with an increase in gain of 0.8 dB

Wideband Oylindrioal Dielectric Resonator Antenna Excited Using an L-strip Feed

A broadband cylindrical dielectric resonator antenna (DRA) energized with an L-strip feed is presented The novel exciting technique achieves a 2:1 VSWR bandwidth of 18%. The variation of bandwidth for different feed parameters is also studied

Wideband Microstrip Antenna Using Hook-Shaped Feed

In this paper, we introduce a novel feeding technique for bandwidth enhancement of a rectangular microstrip antenna This antenna offers an impedance bandwidth of 22% without degrading the effciencv. The effect of the feed parameters upon patch characteristics such as resonant frequency, impedance bandwidth, and radiation pattern are studied in detail. The experimental results are verified using the FDTD results

Corrugated Flanged Horn Feed for Offset Paraboloidal Reflectors

A technique for improving the coupling between a feed horn and reflector by using corrugated metallic flanges is presented. Experimental data for flanges of varying parameters are given and theoretical explanation is supplemented

A Circularly Polarized Corrugated Flanged Feed Horn

Design and development of a circularly polarized and matched H-plane sectorial horn antenna have been reported By proper trimming of the flange parameters any desired polarization can be obtained from the horn

A Strip-Loaded Feed-Horn antenna

Design and development of a new feed -horn antenna with low sidelobe levels is reported . The E-walls of this antenna are fabricated with low -loss dielectric substrate , periodically loaded with thin conducting strips . The antenna is found to be simulating the radiation characteristics of metallic corrugated horns . This can be an ideal substitute for metallic corrugated horns with added advantages like light -weight and low production cost.