Publication Abstract

Effects of temperature, prey type and prey size on gastric evacuation in small cod (Gadus morhua L.) and whiting (Merlangius merlangus L.)

Effects of temperature, prey type andprey size on gastric evacuation in small cod (Gadus morhua L.) and whiting (Merlangiusmerlangus L.)

S. Singh-Renton and P.J. Bromley

Gastriclavage was used to investigate the effects of temperature, prey type and prey size ongastric evacuation in small cod Gachts morhua and whiting Merlangius merlangus. Thefish were fed to satiation and subsequently the stomach contents were sampled to determinethe rate at which food was evacuated. Satiation meal size was positively related totemperature and differed between prey types. The gastric evacuation rate (GER) also tendedto increase with temperature and varied with prey type. GER at temperatures of 11-3-12-7°C averaged 1-5-1-7 times higher than at 6-9-5° C. There was no significant difference(P>0-05) in the evacuation of lug,,vorm Arenicola marina, sandeel Ammocli,tesspp., and herring Chtpea harengus, but the GER of brown shrimp Crangonvulgaris was much slower (P<0-05). No significant changes in GER were observed whenfish were fed on three different size groups of either herring or brown shrimp. Inwhiting, there was no significant difference in the GER of individual herring or brownshrimp when they were fed as single species meals or incorporated in meals containing amixture of prey species.

Reference:

S. Singh-Renton and P.J. Bromley, 1996. Effects of temperature, prey type and prey size ongastric evacuation in small cod (Gadus morhua L.) and whiting (Merlangius merlangus L.).Journal of Fish Biology, 49: 702-713.

S. Singh-Renton and P.J. Bromley*

Journal of Fish Biology, 49: 702-713