The Share of Internal Organs and Viscera in Rainbow Trout (Oncorhynchus Mykiss) Reared in Different Growth Systems

Abstract

In this experiment we followed the influence of growth system on the share of internal organs and viscera by the total body mass on rainbow trout (Oncorhynchus mykiss). The importance of this study results from the need to reach as favourable slaughter yield. For this, were slaughtered 25 rainbow trout from the Fiad trout farm (conventional farm), Bistriţa-Năsăud County (control group – M), respectively 25 rainbow trout grown in a recirculating system arranged in Cluj-Napoca (experimental group – E). Body weight of the studied specimens was 228.96±1.21 g – M group, respectively 229.40±1.24 g – E group, the difference between the two groups being insignificant (p>0.05). The slaughter yield was favorable for E group – 90.55±0.03%, compared with M group – 89.23±0.05% (p<0.001). We analyzed the total gravimetric share of the internal organs and viscera at trout from the two groups and individual weights of esophagus, stomach, pyloric caeca, medium intestine and duodenum, rectum, liver, pancreas, heart, spleen, air bladder and kidney. The results showed a higher share of this organs at trout from the Fiad trout farm (M group), except stomach (2.38±0.01g – M group vs. 2.45±0.008 g – E group; p<0.05), and liver respectively (4.83±0.02 g – M group vs. 5.36±0.04 g – E group; p<0.001). In accordance with the values obtained, the resulting conclusion is that in the recirculating system, due to optimal environmental conditions, trout have a higher slaughter yield compared with those of conventional farm, accumulating in the same time fat reserves deposited in the liver.