Yellow Perch Juveniles Research Articles

Transcriptomic response to soybean meal-based diets as the first formulated feed in juvenile yellow perch (Perca flavescens)

With increasing levels of fish meal (FM) protein in aquafeeds being replaced with soybean meal (SBM) protein, understanding the molecular mechanisms involved in response to alternative diets has become a critical concern. Thus, the goal of this study was to examine transcriptional differences in the intestine of juvenile yellow perch through RNA-sequencing (RNA-seq), after their initial introduction to a formulated diet with 75% SBM protein inclusion for 61 days, compared to those fed a traditional FM-based diet. Transcriptomic analysis revealed a concise set of differentially expressed genes in juveniles fed the SBM-based diet, the majority of which were intrinsic to the cholesterol biosynthesis pathway. Analysis of total body lipid and cholesterol levels were also investigated, with no between-treatment differences detected. Results of this study demonstrate that in response to SBM-based diets, yellow perch juveniles up-regulate the cholesterol biosynthesis pathway in order to maintain homeostasis. These findings suggest that the upregulation of the cholesterol biosynthesis pathway may negatively impact fish growth due to its large energy expenditure, and future studies are warranted.

Growth, Survival, and Body Composition of Yellow Perch Juveniles Fed Commercial and Experimental Diets

AbstractTwo experiments were carried out to evaluate the efficacy of commercial and experimental diets on the survival, growth, and body composition of juvenile yellow perch Perca flavescens. In both experiments, fish were fed by hand four to five times a day at a restricted ration of up to 90% satiation for 51 d. In experiment 1, fish (initial weight, 87 ± 24 mg) were fed three experimental diets (F1, F2, and a casein‐gelatin‐based diet) and one commercial diet (Kyowa 400B). In experiment 2, fish (initial weight, 174 ± 56 mg) were fed four experimental diets (Kyowa 400B, INVE‐NRD, a starter diet from BioOregon, and a starter diet from Purina). In both experiments, the growth performance of yellow perch juveniles was significantly affected by dietary treatments. In experiment 1, fish fed Kyowa 400B and the casein‐gelatin‐based diet grew significantly faster than those fed the F1 and F2 diets. However, survival was significantly lower in fish fed the casein‐gelatin‐based diet than in those fed the other dietary treatments. In experiment 2, fish fed the INVE‐NRD diet exhibited the best growth performance. Survival was not affected by dietary treatments. In both experiments, the proximate composition of fish among dietary treatments reflected the proximate composition of the diet. Our results indicate that satisfactory growth of yellow perch juveniles can be achieved using commercial and experimental diets.

Lack of growth enhancement by exogenous growth hormone treatment in yellow perch ( Perca flavescens) in four separate experiments

The effect of exogenous growth hormone (GH) treatment on the growth of juvenile yellow perch ( Perca flavescens) was investigated in four experiments. In the first two experiments, juvenile yellow perch were reared at either 13 °C or 21 °C, and injected weekly with bovine GH (bGH) at 0.1, 1.0 or 10.0 μg/g body weight for 84 days. No significant growth enhancement in GH-treated fish was measured in fish in either of the experiments. In the third experiment, juvenile yellow perch were treated with estradiol-17β (E 2, 15 μg/g of diet), bGH (1.0 μg/g body weight) injected weekly or both hormones for 70 days at 21 °C. E 2 alone stimulated growth, but no further growth stimulation occurred in the E 2 + bGH-treated fish. In addition, no growth enhancement was found in fish treated with bGH alone. We measured no difference in serum insulin-like growth factor-I (IGF-I) levels between the treatment groups at 12 and 24 h after the final injection of GH; however, a drop in IGF-I levels after 24 h was observed. In a fourth study, the effect of recombinant yellow perch GH (rypGH, 0.2 or 1.0 μg/g body weight) injected weekly was evaluated in yellow perch juveniles. The fish were reared for 42 days at 18 °C. Neither GH dosages improved growth compared to control-injected and non-injected fish. Taken together, the lack of effect of mammalian GH or rypGH in our experiments suggests (1) low binding affinity between these hormones and the GH receptor in yellow perch, (2) that the endogenous GH levels were already at biologically maximal levels or (3) that other endocrine factors are needed in order for GH to promote yellow perch growth. The reduction in IGF-I levels 24 h after handling suggests a negative effect of handling stress on the GH-IGF-I axis in yellow perch.

Overwintering Yellow Perch Fry in Alabama

Abstract Wild harvests of yellow perch Perca flavescens have failed to keep up with the strong market demand for the fish. Moreover, yellow perch has many attributes that make it attractive for commercial aquaculture in the USA. One drawback to yellow perch culture in the north-central region of the United States is that low winter water temperatures inhibit somatic growth. In this study, yellow perch juveniles were stocked at three densities (30, 60, and 90 per tank) in 600-L tanks in Auburn, Alabama, in early January and maintained throughout the winter until mid-April. Water in the tanks was circulated through an earthen pond and returned to the research system by means of a water pump. Tanks were aerated by means of submersible air diffusers and a regenerative air blower. Fish were offered a commercial, slow-sinking feed at 5% of body weight, and temperature was measured hourly by a remote data logger. Survival was greater than 99% in all treatments. When water temperature was below 20°C, absolute gro...

Long-term effects and interactions of dietary vitamins C and E on growth and reproduction of yellow perch, Perca flavescens

This study was conducted to examine the effects of dietary vitamin C and/or E and their interaction on growth and reproductive performance in yellow perch. Yellow perch juveniles were divided into four treatments with triplicate groups and fed with one of four semi-purified diets for 32 weeks. The experimental diets were formulated to contain no or high vitamin E levels (160 mg/ kg) without or with vitamin C supplementation (250 mg/kg) designated as diets –C –E, – C + E, + C – E, or + C + E, respectively. The growth rates and survival of yellow perch fed with + C — E and + C + E diets were significantly higher than the fish fed with — C — E diet. Total- and dehydro-ascorbate concentrations in liver and testis increased in response to its dietary supplementation. The α-tocopherol concentration in sperm was significantly affected by dietary supplementation of vitamin C. Gonadosomatic index of males was lower in the fish fed with — C — E diet compared to that of fish fed with other diets. Hatching rates of embryos obtained from testing sperm viability was significantly improved in fish fed with the diets sufficient in vitamin C (82 ± 7%) compared to the fish fed with the — C — E diet (59 ± 7). This study indicates that supplementation of dietary vitamin C and E increase growth rate, and semen quality can be improved by dietary vitamin C supplementation within one maturation cycle, and vitamin C may spare sperm vitamin E depending on vitamin E stores in tissues.

The Effect of Microdiet Supplementation of Dietary Digestive Enzymes and a Hormone on Growth and Enzyme Activity in Yellow Perch Juveniles

Abstract Juvenile yellow perch Perca flavescens were evaluated to assess their needs for exogenous digestive enzyme and hormone supplementation in dry diets. Evidence exists to support the hypothesis that these supplements may assist young fish in digestion. Four diets were tested: A commercially available trout starter; an experimental diet based on high quality fish meals and squid meal; and the experimental diet supplemented with either 0.1% (by weight) bombesin (digestive tract neurohormone) or pancreatin (digestive enzyme extract). Fish fed all diets had similar growth. Survival was high and was not significantly different between treatments. Specific activities for both trypsin and chymotrypsin were not significantly different between diets, indicating that digestive enzyme supplementation was not necessary in tested juveniles. Specific activities for pepsin were also not significantly different between treatments, indicating supplementation of dry diets with the digestive hormone bombesin did not a...

Use of Krill Hydrolysate as a Feed Attractant for Fish Larvae and Juveniles

Abstract.— We determined the effect of krill hydrolysate as a feed attractant in three freshwater fish species: yellow perch Perca flavescens. walleye Stizostedion vitreium. and lake whitefish Coregonus clupeaformis. Growth trials were conducted using a commercial trout starter diet (control) and the diet that was coated with liquid krill hydrolysate. The krill hydrolysate coated diet increased growth of yellow perch juveniles by 31% compared to control diet (average final wet weight, 734 ± 33 mg and 559 ± 82 mg, respectively). Moreover. weight gains were not significantly different than for tish Id exclusively live Artemiu nauplii. Similar results were obtained with walleye juveniles fed either a trout starter diet or 5% krill hydrolysate coated diet (8.9 ± 0.25 g and 11.6 ± 5.1 g wet weight, respectively). The food conversion ratio (FCR) was lower in fish fed the control diet, although not significantly different (2.95 ± 0.18 and 3.69 ± 0.39. for control and coated diet. respectively). The effect of krill hydrolysate on dry diet ingestion rates of lake whitefish and yellow perch larvae was also determined using radioactive (14C) labelling. A commercial starter diet was coated with krill hydrolysate or the soluble fraction of krill hydrolysate was added to the experimental tank water. In both species. coating the diet with 5% krill hydrolysate resulted in significantly higher ingestion rates. Supplementation of krill hydrolysate soluble fraction to the tank water resulted in 200% increase in ingestion rate in comparison to control (uncoated starter diet), although it was not significantly different from krill coated diet and live Artemia nauplii ingestion rates.