In the present study, fish meal (FM) was replaced by pea (Pisum sativum) protein (PP) in diet for Rainbow trout (Oncorhynchus mykiss) at levels of 0% (PP0), 25% (PP25), 50% (PP50), 75% (PP75) and 100% (PP100), and the effect of dietary PP level on the digestive system tracts and liver was investigated by micromorphological and histopathological evaluations. Morphometric measurements (mm 100g fish −1 ) of the liver width and stomach length in rainbow trout were found to be significantly larger (p <0.05) in fish with high-level pea protein as the main protein source (PP75, PP100) compared to the low-level PP replacement group (PP25). No significant differences were found in morphometric measurements for pyloric caecum and intestines among treatment groups, whereas the number of the caecum of fish fed the PP25 diets significantly increased over the control (PP0) (p<0.05). In the histological examination of the liver, mild hydropic and vacuolar degeneration was observed in all experimental groups except PP0 and PP25. The measurements of pyloric caecum fold height, enterocyte length and width of tunica muscularis of the high-level pea protein groups of PP75 and PP100 were significantly higher (p <0.05) compared to the control group. In conclusion, 25% substitution of PP can be suggested for FM in trout diets, because the findings of the present study provided evidence that the digestive system improved by increasing the number of pyloric caecum at this replacement level.
AbstractCommon carp (Cyprinus carpio) is the most farmed freshwater fish worldwide. In recent years, use of natural products in fish diets has become popular in aquaculture, to improve fish health and growth performance. The present study investigated the effects of essential oil from the leaves of Monterey cypress (Cupressus macrocarpa; CMEO) on growth performance and blood parameters in common carp fingerlings. Identification of 96.1% of the CMEO total volatile components was achieved, with the highest contents for terpinen-4-ol and α-pinene, at 22.9% and 47.7%, respectively. After 60 days of feeding of the fingerlings with supplemented diets without CMEO (CMEO 0%) and with CMEO at 0.5%, 0.75% and 1%, the best growth performance was seen for those fish fed with the CMEO 0.5% diet. No significant differences were seen for the haematological parameters and blood cell indices versus CMEO 0%. Serum glucose, triglycerides, cholesterol and glutamic pyruvic transaminase were significantly reduced in the fingerlings fed with the CMEO 0.5% diet versus CMEO 0%. Thus, CMEO oil as a 0.5% dietary supplement can be used to improve the growth performance and health status of the common carp without any adverse effects seen.
As from January 2010 The Israeli Journal of Aquaculture-Bamidgeh (IJA) will be published exclusively as an on-line Open Access (OA) quarterly accessible by all AquacultureHub (http://www.aquaculturehub.org) members and registered individuals and institutions. Please visit our website (http://siamb.org.il) for free registration form, further information and instructions. This transformation from a subscription printed version to an on-line OA journal, aims at supporting the concept that scientific peer-reviewed publications should be made available to all, including those with limited resources. The OA IJA does not enforce author or subscription fees and will endeavor to obtain alternative sources of income to support this policy for as long as possible.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.