Effects of dietary scallop and squid hydrolysates on growth of European seabass, Dicentrarchus labrax; California yellowtail, Seriola lalandi; and barramundi, Lates calcarifer

Lee, C.M., B. Volson, B. Kang, P.D. Karayannakidis, E. Gamez, J. Miller, G. Betty, C. Andrikos, A. Attwater, and D.A. Bengtson

Squid processing byproducts and scallop viscera contain high protein levels and good amino acid and fatty acid profiles. Lee et al. (2018) evaluated hydrolysates developed from these byproducts in a series of feeding trials. Inclusion of hydrolysates improved feed attractability and growth in early juvenile, but not growout stages of European seabass and California yellowtail, but no discernible benefit was found with barramundi. [Full Article]

Molecular cloning and characterization of a putative ecdysis-triggering hormone receptor (ETHR) gene from Macrobrachium nipponense.

G-X Liang, H-T Fu, H Qiao, S-M Sun, W-Y Zhang, S-B Jin, Y-S Gong, S-F Jiang, Y-W Xiong, and Y Wu

The molting process in crustaceans is complex and requires coordinated gene expression of multiple regulatory chemical messengers. Liang et al. (2018) cloned the full-length complementary DNA of a putative ETHR gene of Macrobrachium nipponense (ETHR). The brain was found to be the major functional site of ETHR activity, and study results indicated that the putative ETHR is closely involved in the molting process of M. nipponense.  [Full Article]

Plant products in compounded diets are effectively utilized by American alligator, Alligator mississippiensis.

Reigh, R. and M.B. Williams

In spite of the importance of alligator farming in several regions of the world, little is known about their nutritional requirements. Reigh and Williams (2018) compared combinations of commercial and experimental, plant-based diets over a 328-d trial. Results indicated that the American alligator can effectively utilize plant products in a compounded diet and that additional research on optimizing the use of selected plant products in alligator feeds is warranted. [Full Article]

Economics of alternative catfish production technologies.

Kumar, G., C. R. Engle, T. R. Hanson, C. S. Tucker, T. W. Brown, L. B. Bott, L. A. Roy, C. E. Boyd, M. S. Recsetar, J. Park, and E. L. Torrans.

U.S. catfish production has become increasingly more intensive. Kumar et al. (2018) compared the economics of three new production systems under a uniform set of economic assumptions. The split-pond system resulted in the lowest cost/kg, followed by that of intensively aerated ponds, with the highest cost/kg from in-pond raceways. Risk analysis showed that intensively aerated ponds may be preferable during times of adverse feed and fish prices. [Full Article]