Rearing of the Nile tilapia (Oreochromis niloticus) on diets containing cotton seed meal enriched with vitamin E

Abstract

ABSTRACThe present experiment was conducted to evaluate the effect of α-tocopherol as an antioxidant for avoiding the side effects of incorporation of cottonseed meal (CSM) in the diet of the Nile tilapia as a replacer of fish meal (FM). Two diets were prepared; the first one contained fish meal and was considered as a control, in the second diet, FM was completely replaced by CSM. The second diet was divided into ten parts, the first one is a control and the other 9 diets were enriched with increased levels of vitamin E (1, 5, 10, 15, 20, 25, 30, 35 and 40 times of gossypol in CSM). Each diet was offered in three aquaria (3 replicates for each diet) and each aquarium was stocked with 25 fish (2.0-2.1g). Results are summarized in the following: -The highest average body weight (9.91 g) was recorded for the control group fed on the basal diet (contained FM) and the lowest BW (5.66 g) was obtained for fish fed the diet D2 in which FM was completely replaced by CSM without vitamin E. Incorporation of vitamin E in the experimental diet significantly improved the BW. Similar trend was observed for the other growth performance parameters body length (BL), weight gain (WG) and specific growth rate (SGR). -The best feed conversion ratio (FCR) was recorded for fish group fed on the diets D1 and D3 which significantly differed from values recorded for the other treatments. The worst FCR was recorded in fish group fed on the diet D2 in which FM was completely replaced by CSM without addition of vitamin E. Incorporation of vitamin E in the experimental diets improved FCR specially fish group fed on the diet D3. -Protein content of the whole fish body ranged between 41.33 to 50.97% and the differences were significant. Fat content of fish fed the diet D2 significantly higher than those obtained for fish fed the other groups. Compared to the two control diets D1 and D2 all vitamin levels in the experimental diets increased ash content of the fish whole body and the graded levels of vitamin E in the diets significantly altered the ash content of tilapia fish. -The highest values for hematocrite (Ht) and haemoglobin (Hb) were obtained for fish fed on the control diet (D1). Incorporation of vitamin E in the experimental diets at increasing levels significantly affected Hb and Ht. Compared to the control group (Diet1) aspartate transaminase (AST) and alanine transaminase (ALT) levels significantly increased fish groups fed on the other experimental diets.

Protective role of lycopene and vitamin E against diazinon-induced biochemical changes in Oreochromis niloticus

“…The level of lipid peroxidation was significantly decreased in different tissues of DZNexposed fishes fed diets supplemented with vitamin E and/or lycopene. Similar results for vitamin E were observed in different fish (Abdel-Monem et al, 2012;Soltan et al, 2011).…”

“…Diet supplementation with LYC and/or VE for 14 and 28 days showed improvement in behavioral changes and the fishes were noticed in better conditions. Similar results for vitamin E and lycopene were observed by Ohaida (2005), Mekkawy et al (2011Mekkawy et al ( , 2013, Soltan et al (2011) andUral (2013). Diazinon insecticides induce oxidative stress leading to generation of free radicals and alteration in antioxidant enzymes or oxygen free radicals scavenging enzyme (ElShenawy et al, 2010).…”

Growth, survival and immune responses of juvenile common carp Cyprinus carpio fed with diets enriched with α- tocopheryl acetate

“…Best FCR was also observed in treatment T4 indicating that good enrichment practice would positively affect the juvenile common carps. According to Solan et al (2011), incorporation of low concentration of vitamin E in to fish feed has positively improved the FCR in Tilapia. Parakrama et al (2011) have shown that vitamin E enriched feed has increased FCR in the post larvae of freshwater prawn.…”