Incidence of skeletal deformities in induced triploid rainbow trout Oncorhynchus mykiss (Walbaum, 1792)

Abstract

Due to the cytogenetic incompatibility, triploid fish are usually infertile and are not affected by a decline in growth, survival and meat quality, which accompanies the process of sexual maturation in diploid specimens. Thus, artificial triploidization has been proposed for fish production in the case of species with early sexual maturation, such as rainbow trout. However, the use of this technique is limited by increased ratios of skeletal deformities observed in triploid specimens. The main objective of this research was to compare the proportion and variety of body abnormalities in diploid and triploid 14-month-old rainbow trout from commercial stocks, using external body shape examination, radiography and whole-mount skeletal staining. Individuals with externally observed body deformities (scoliosis, humpback, shortened tail and jaw deformities) accounted for 0.45% of the diploid stock and 3.83% of the triploid stock. X-rays and whole-mount skeletal staining of deformed individuals showed spine deformities, including compressions and fusions of vertebrae. Abnormalities observed in diploid and triploid rainbow trout examined during this study were non-lethal, however, they may negatively affect the condition of fish. Fish with skeletal deformities are not aesthetically pleasing, thus an increased ratio of such deformations in fish produced for commercial purposes may result in real economic losses.

RNA-Seq Analysis of the Growth Hormone Transgenic Female Triploid Atlantic Salmon (Salmo salar) Hepatic Transcriptome Reveals Broad Temperature-Mediated Effects on Metabolism and Other Biological Processes

“…Potentially due to differences in cellular dimensions and decreased cellular surface-to-volume ratio ( Piferrer et al, 2009 ), triploids are also more prone to skeletal deformities and the development of cataracts ( Sambraus et al, 2017b ; Fraser et al, 2020 ; Jagiełło et al, 2021 ), which has led to the recommendation to increase dietary phosphorus and histidine for triploids to address each of those respective issues ( Burke et al, 2010 ; Fjelldal et al, 2015 ; Taylor et al, 2015 ; Smedley et al, 2016 ). Therefore, these nutrients were important considerations in both past ( Ignatz et al, 2020b ) and present studies.…”

Deformities in fish: A barrier for responsible aquaculture and sustainable fisheries

“…Amoroso et al 193 also observed a higher incidence of lower jaw skeletal anomalies in triploid Atlantic salmon, S. salar . Jagiełło et al 194 found that the body deformities (scoliosis, humpback, shortened tail and jaw deformities) were 0.45% in the diploid stock. In contrast, it was 3.83% in the triploid stock of rainbow trout, O. mykiss .…”