Effects of triploidy on feed efficiency, morphometric indexes and chemical composition of shi drum, Umbrina cirrosa L.

Abstract

Productive performances of triploid (3n) and diploid (2n) shi drum (Umbrina cirrosa L.) were evaluated over an experimental period of 76 days. Fish, selected according to body weight (196 specimens from each ploidy), were reared in tanks (two for each thesis) under the same environmental and dietary conditions. A practical extruded diet (crude protein: 43.4%; ether extract: 19.3%) was offered to fish according to a feeding rate that varied from 1% to 1.5% of live weight. Both at the beginning and at the end of the trials, samples of fish were submitted to morphometrics and chemical analysis. The final body weight and the specific growth rate of triploid fish were significantly lower than those of fish diploid. The feed efficiency of triploids showed a reduction in crude protein retention. Juvenile triploids evidenced a larger amount of coelomatic fat, and their gonads were atrophic. The whole-body proximate composition of 3n fish was characterized by a higher ether extract and a lower crude protein content than 2n fish. Triploids had higher liver lipid content; there were no significant differences in viscera proximate composition. Sum, the results showed that chromosome set manipulation in this species can reduce productive performances at a juvenile stage, influencing some morphometric traits

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“…On the other hand, our results showed a higher content of moisture and protein and lower total fat and ash content than those obtained by Segato et al (2006) and Zafer et al (2012) for whole-body of shi drum. These results may be explained because the total fat in our study did not include viscera, like the liver which has a high fat content.…”

“…Mean values (± SEM) of the nutritional parameters from the 16L:8D group of the present study. Our results are compared with the results found in shi drum by Segato et al (2006Segato et al ( , 2007 (mean values ± SD) and Zafer et al (2012) 16L:8D group (dorsal and ventral fillet) Dorsal fillet (Segato et al, 2007) Whole-body (Segato el al., 2006) Whole -body (Zafer et al, 2012 Imsland et al (2013) studied the long-term effect of photoperiod manipulation for 46 months and found that the shortterm exposure to 24L stimulated growth, whereas the long-term rearing at 24L reduced growth. Thus, at harvest, the greatest mean weights were reached in the group previously kept to short-term exposure at 24L and then transferred to 16L:8D until harvest.…”

Effects of dietary lipid levels on growth, nutrient utilization, and nitrogen and carbon balances in shi drum (Umbrina cirrosa L.)

“…SGR results obtained in the present study were poorer than those calculated by Segato et al (2005a, b) but similar to those by Segato et al (2006) who used bigger fish (*290 g) and Mylonas et al (2009) who used smaller fish (*23 g) compared with those (72. 6 g) used in the current study.…”

“…Although shi drum has a great potential for aquaculture, only limited information on its nutritional requirements is available. Previous studies on shi drum have dealt with its reproductive biology and osmoregulation (Mylonas et al 2004(Mylonas et al , 2009, histological changes in digestive tract during larval development (Zaiss et al 2006), triploidy, and quality traits (Segato et al 2006(Segato et al , 2007. The nutritional information available thus far is related to the potential use of vegetable protein and oil sources in its diets (Segato et al 2005a) and dietary protein requirement (Akpinar et al 2011).…”

Comparison of growth performance, biochemical and fatty acid compositions between all-female diploid and triploid rainbow trout Oncorhynchus mykiss (Walbaum, 1792)

“…Poontawee, Werner, Müller-Belecke, Höstgen-Schwark, and Wicke (2007) reported that there was a significant difference between 6.5 year-old diploid and triploid rainbow trout in terms of fat and moisture, but that the ploidy leveldid not affect the protein contents. Segato et al (2006) reported that triploid shi drums (Umbrina cirrosa) deposited more fat in their livers than did the diploids.…”