Partially Defatted Hermetia illucens Larva Meal in Diet of Eurasian Perch (Perca fluviatilis) Juveniles

Insect meal is gaining increased attention in aquafeed formulations due to high protein content and an essential amino acid profile similar to that of fishmeal. To investigate insect meal in feed for European perch Perca fluviatilis, a promising candidate for European intensive culture, we replaced standard fishmeal with partially defatted black soldier fly Hermetia illucens larva meal at rates of 0%, 20%, 40% and 60% (groups CON, H20, H40 and H60, respectively) and compared growth performance, somatic indices, hematological parameters, whole-body proximate composition and occurrence of spleen lipidosis. In addition, we assessed the economic and environmental sustainability of the tested feeds by calculating economic conversion ratio (ECR) and economic profit index (EPI). The tested groups did not differ in survival rate. Significant differences were documented in final body weight and specific growth rate, with the highest values in CON, H20 and H40. The proximate composition of fish whole-body at the end of the experiment did not differ in dry matter, crude protein or ether extract, while organic matter, ash and gross energy composition showed significant differences. The fatty acid content and n-3/n-6 ratio showed a decreasing trend with increasing H. illucens larva meal inclusion. No differences were found in hematological parameters among tested groups. The H. illucens larva meal inclusion significantly affected ECR and EPI, even at 20% inclusion level the cost of diets did not differ from the control fish meal based diet. Results suggested that 40% inclusion of H. illucens larva meal can be used successfully in standard diets for perch.

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Slaughter yield, proximate composition, and flesh colour of cultivated and wild perch (Perca fluviatilis L.)

Czech Journal of Animal Science ◽

10.17221/2279-cjas ◽

2008 ◽

Vol 52 (No. 8) ◽

pp. 260-267 ◽

Cited By ~ 11

Author(s):

B. Jankowska ◽

Z. Zakęś ◽

T. Żmijewski ◽

M. Szczepkowski ◽

A. Kowalska

Keyword(s):

Body Weight ◽

Proximate Composition ◽

Dry Matter ◽

Body Height ◽

Perca Fluviatilis ◽

Yellow Pigment ◽

Flesh Colour ◽

Perch Perca Fluviatilis ◽

Formulated Feed ◽

Maximum Body

The aim of this research was to determine the slaughter yield, proximate composition, and flesh colour of cultivated and wild perch (Perca fluviatilis). The study material was composed of fish obtained from intense fattening on formulated feed (age 1+, mean body weight (BW 116 g)) and wild specimens caught in a lake (age 3+, BW 119 g). The biometric traits of the two groups of fish did not differ with regard to body weight, total length (Lt), body length (Lc), or condition coefficient (P > 0.01). The cultivated perch had both higher maximum body height (H) and relative body profile (Rp) (P ≤ 0.01). The cultivated perch has a significantly lower slaughter yield (P ≤ 0.01). This dependence stems from the heavier viscera, which included more perivisceral fat and larger liver. Cultivated perch had significantly higher values of the viscerosomatic (VSI; 12.0 vs. 6.4), hepatosomatic (HSI; 1.9 vs. 1.7), and perivisceral fat (IPF; 7.0 vs. 1.2) indices. The analysis of the proximate composition of fillets from wild and cultivated perch indicated that the ratios of protein, fat, water were significantly different (P ≤ 0.01). The higher content of dry matter in the cultivated perch was a result of higher fat and protein contents. The fillets of the two groups of perch differed with regard to the saturation of green and yellow pigment; the cultivated perch exhibited lower values of parameter a* and higher values of parameter b* (P ≤ 0.01).

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Tissue-specific uptake of the benzodiazepine oxazepam in adult Eurasian perch (Perca fluviatilis)

Environmental Chemistry ◽

10.1071/en16027 ◽

2016 ◽

Vol 13 (5) ◽

pp. 849 ◽

Cited By ~ 10

Author(s):

Martina Heynen ◽

Tomas Brodin ◽

Jonatan Klaminder ◽

Micael Jonsson ◽

Jerker Fick

Keyword(s):

Blood Plasma ◽

Perca Fluviatilis ◽

Fish Tissue ◽

Whole Body ◽

Eurasian Perch ◽

Tissue Specific ◽

Perch Perca Fluviatilis ◽

Specific Uptake ◽

Specific Muscle ◽

Species Specific

Environmental contextAlthough pharmaceuticals are found in wild fish, there is no consensus as to which fish tissue to use when measuring the pharmaceutical concentrations. Using the psychiatric pharmaceutical oxazepam in Eurasian perch as an example, we found that oxazepam was distributed in the perch tissues in the following order of concentration: muscle<liver=brain<blood plasma. These results help to interpret and compare previous studies, and provide guidance for future studies. AbstractPsychoactive substances are used worldwide and constitute one of the common groups of pharmaceutical contaminants in surface waters. Typically, in field surveys and laboratory studies, muscle or whole-body homogenates are used to quantify pharmaceutical concentrations in biota, although uptake of pharmaceuticals may be tissue-specific. Therefore, the aim of this study was to investigate the tissue-specific (muscle, liver, brain and blood plasma) uptake of the anxiolytic oxazepam in adult Eurasian perch (Perca fluviatilis). In laboratory experiments, perch were exposed to four different concentrations (2, 4, 12 and 20µgL–1) of oxazepam for 6 days, and muscle, liver, brain tissue and blood plasma were sampled to determine tissue-specific bioconcentration. We found that the tissue-specific bioconcentration was independent of oxazepam concentration. However, among tissue types, bioconcentration was significantly different, with the concentration in muscle<liver=brain<blood plasma. Hence, it is important to consider the type of tissue used to quantify pharmaceutical uptake in fish, for predictions of species-specific sensitivity and comparisons across studies. Furthermore, our results indicate a somewhat lower transportability (brain/plasma ratio 0.54) of oxazepam from blood to brain in fish compared with in mammals, which should be kept in mind when employing ‘read-across’ approaches.

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