Location: Aquatic Animal Health Research
Title: Enhancement effects of dietary wheat distiller's dried grains with solubles on growth, immunology, and resistance to Edwardsiella ictaluri challenge of channel catfish, Ictalurus punctatus Authors
Submitted to: Aquaculture America Conference
Publication Type: Abstract Only
Publication Acceptance Date: November 10, 2011
Publication Date: February 29, 2012
Citation: Li, E., Lim, C.E., Cai, C., Klesius, P.H. 2012. Enhancement effects of dietary wheat distiller's dried grains with solubles on growth, immunology, and resistance to Edwardsiella ictaluri challenge of channel catfish, Ictalurus punctatus. Aquaculture America 2012. p. 289. Technical Abstract: This study evaluated the effects of the inclusion of wheat distiller’s dried grains with solubles (WDDGS) at levels of 0 (control), 10, 20, 30 and 40% without (diets 2-5) and with (diets 6-9) lysine supplementation, as substitutes of soybean meal and corn meal mixture on growth, body composition, hematology, immune response and resistance of channel catfish (average initial weight, 5.97±0.14g) to Edwardsiella ictaluri challenge. After 12 weeks of feeding, fish fed diet 5 had the lowest weight gain (WG), feed efficiency ratio (FER), protein efficiency ratio (PER), feed intake (FI), survival. The differences, however, were not always significant, such as FER and PER of this group of fish did not differ from those fed diets 1 and 4. Fish fed diets 7-9 had significantly higher WG, FER and PER than fish fed diet 1. Body protein decreased in fish fed diets 4 and 5, while body lipid tended to increase in fish fed WDDGS containing-diets, regardless of lysine supplementation. Fish fed diet 5 developed anemia as shown by lower values for red and white blood cell counts, hemoglobin and hematocrit. The number of days at which the first mortality occurred was delayed and cumulative mortality 21 days post challenge with E. ictaluri was lower in fish fed WDDGS containing-diets as compared to fish fed the control diet. However, further decrease in mortality was obtained in the groups fed diets with 20 to 40% WDDGS, either with or without supplemental lysine. Serum protein, total immunoglobulin and lysozyme activity were not affected by dietary treatments. Serum complement and antibody titer against E. ictaluri significant differed among treatments but did not appear to follow the trend observed for cumulative mortality following experimental challenge.