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The effects of replacing fish meal (FM) with shrimp waste meal ( SWM) in diets fed to juvenile cobia ( Rachycentron canadum) were investigated through a 6-week trial. SWM was added to replace FM at fractions of 0%, 10%, 20% and 25% of the diet. The result showed the survival rates of the fish were higher than 86.7%. The weight gain and feed conversion rate showed an increasing trend as the SWM proportion in diet increased from 0% to 25%, but the protein efficiency ratio showed a decreasing trend in efficiency. In addition, the hepatosomatic index increased significantly when the SWM percentage was 20% and 25%. There were no significant differences in the protein and ash concentration of the muscle among all dietary groups. However, the muscle lipid content was low when fish fed in diets with high SWM level. Chitinase activity was extremely high in the pyloric caeca tissue of cobia, and increased specific activities of chitinase were only found in the foregut of cobia fed diets containing 10% SWM for a 6-week period. A challenge test showed that SWM could not enhance cobia resistance to Photobacterium damselae ssp. piscicida infection. Our results suggest that the administration of a 10% SWM diet could potentially reduce the use of FM in the diet of cobia. [ABSTRACT FROM AUTHOR]

Abstract: Selective H-atom line broadening was found to be present throughout the volume ( length) of low pressure (0.03–0.4Torr) H2O only RF plasmas generated in an RF capacitively coupled parallel-plate cell. An exhaustive study of the first four Balmer lines in water plasmas operated over a range of pressures and absorbed powers revealed significant trends. Of greatest interest was the finding that at low pressures (ca. ) a significant fraction (between 10% and 40%) of the atomic hydrogen was ‘hot’ with energies greater than 40eV. The magnitude of the line broadening was found not only to be pressure dependent, but also to be a weak function of the energy absorbed by the system. The degree of broadening was virtually independent of the position studied within the RF capacitively coupled parallel-plate cell, similar to the finding for H2/He and H2/Ar plasmas in the same capacitively coupled cell, reported elsewhere. In contrast to the atomic hydrogen lines, no broadening was observed in oxygen species lines at low pressures. Also, in ‘control’ H2/Xe plasmas run in the same cell at similar pressures and adsorbed power, little broadening of either atomic hydrogen, Xe or any other lines was observed. The values of the line broadenings observed in the low pressure water plasmas, and the fact that they were observed throughout the volume, are consistent with predictions of the Mills model, CQM, of populating fractional quantum states in H-atoms via catalytic resonant transfer processes. In particular CQM predicts that O2 can act as a catalyst for the RT process, and spectroscopy shows the water plasma contain a significant O2 population. Standard physics models of preferential hydrogen line broadening, developed explicitly for hydrogen/argon mixtures, are clearly not consistent with any aspect of the behavior observed in the water plasma data reported here. [Copyright &y& Elsevier]