Effect of body weight and different level of feeding on growth performance, carcass composition and digestibility of rainbow trout (Oncorhynchu smykiss)

Oraji, Hossein; Dehghan, Elham; Keramat, Abdolsamad; Jani Khalili, Khosro

Effect of body weight and different level of feeding on growth performance, carcass composition and digestibility of rainbow trout (Oncorhynchu smykiss)

Authors

Hossein Oraji ¹

elham dehghan ¹

Abdolsamad Keramat ²

Khosro jani Khalili ¹

¹ Agricultural Sciences and Natural Resources University

² Sari Agriculture Sciences and Natural Resources University

Abstract

The present study was to evaluate the impact of feeding level and fish size on the growth factors,carcass composition and digestibility of rainbow trout. Six experimental treatments were assigned by the use of three feeding levels (maintenance, medium and satiation levels) and two fish sizes (43.02 ± 2.93 and 231.32± 6.74g) according to a 3×2 factorial design. There were three replicates for each treatment and the experiment lasted for 59 days. The results showed that there is a significant interaction effect between fish size and feeding level for body weight gain, final body weight and specific growth (p<0.05). Body composition (dry matter, energy, moisture, fat and protein) was affected by feeding level and size of the fish (p<0.05). However, the interaction effect between fish size and feeding level for body composition was not significant (p>0.05).The digestibility measurements showed that fish size and feeding level changed significantly digestibility of protein, lipid, energy and dry matter in rainbow trout (p<0.05). Maximum growth at satiation feeding level can reduce feed conversion ratio and increase waste production at both fish sizes.

Keywords

maintenance

Satiation

Specific growth rate

Digestibility

Rainbow trout