Які соціально-економічні наслідки матиме скасування мораторію на продаж земель сільськогосподарського призначення в Україні?

This study investigated the long-term effects of total and partial replacement of dietary fish meal (FM) by a mixture of agricultural products on sperm quality of African catfish Clarias gariepinus. Four isonitrogenous and isoenergetic diets were formulated containing graded levels of either 50% FM and maize meal (diet 1); 25% FM mixed with crude sunflower oil cake (SFOC) and bean meal (BM) (diet 2); 12.5% FM mixed with sunflower oil cake, BM and ground nut oil cake (GOC) (diet 3) and 0% FM mixed with de-hulled sunflower oil cake (SFOCD), BM and ground nut oil cake (diet 4). Gonadosomatic index (GSI), sperm quality, plasma sex steroids (11-keto testosterone [11-KT]; testosterone [T]; estradiol-17beta [E2]) were evaluated on 10 to 24 fish fed on each diet. Sperm quality was assessed using computer-assisted sperm analysis (CASA). Total replacement of fish meal by plant products markedly increased sperm volume, spermatocrit, spermatozoa integrity, and sperm motility. Fish fed diet 3 (12.5% fish meal) provided intermediate results on sperm quality whereas the lowest values were obtained in fish fed diets 1 and 2. In fish fed 0% fish meal (diet 4), androgen levels were higher and estrogen levels were lower than in fish fed fish meal diets. Based on dietary lipid and fatty acid analyses, these results suggest a positive impact of short chain n-6 fatty acids on androgen synthesis and sperm quality. In conclusion, a combination of ground nut oil cake, bean meal and sunflower oil cake (preferably when the sunflower is dehulled) in African catfish diet improves the sperm quality

Rearing conditions and life history influence the progress of gametogenesis and reproduction performances in pikeperch males and females

International audienc

Efficiency of fatty acid-enriched dipteran-based meal on husbandry, digestive activity and immunological responses of Nile tilapia Oreochromis niloticus juveniles

peer reviewedThis study aimed to compare the enrichment capacity of polyunsaturated fatty acids (PUFA) and the long chain polyunsaturated fatty acids (LC-PUFA) of two dipteran species, Hermetia illucens - black soldier fly (BSF) - and a blowfly, Chrysomya putoria (CP), and to test its influence on growth, digestive activities and immune responses of Nile tilapia. Two types of enriched insect larval meal were produced using larvae cultured either on vegetable substrates (VGS) to formulate two diets rich in linolenic acid (ALA) (BSF/VGD and CP/VGD), or on fish offal substrates (FOS), in order to produce two diets rich in ALA and eicosapentaenoic acid (EPA) (BSF/FOD) or in ALA + EPA and docosahexaenoic acid (DHA) (CP/FOD). These four insect-based diets containing only palm oil as a lipid source were compared to a control diet based on fish meal (FM) and fish oil (FO). After 60 days of feeding, ALA or DHA muscle content of fish fed BSF/VGD or CP/FOD diet was comparable to that of the FMFO diet, and all insect diets increased the EPA muscle levels, except for a reduction by the BSF/VGD one. The CP/FOD diet induced similar fish growth, feed efficiency and protein efficiency ratio compared to the control FMFO diet, while a decrease was observed in fish fed other insect diets. Only BSF/VGD led to a decrease in protein and lipid digestibility. CP or BSF larval meal significantly increased alkaline phosphatase activity regardless of fatty acid (FA) enrichment. The expression level of fads2, fads6 and elovl5 was significantly higher in fish fed the BSF/VGD diet compared to fish fed the FMFO diet. FA-enriched insect diets increased some immune variables such as lysozyme, peroxidase and ACH50 values of fish fed CP/FOD, CP/VGD or BSF/VGD diets. Moreover, the expression level of β-defensin-1 and mhcII genes were significantly higher in fish fed the BSF/FOD diet than the FMFO diet. Also, the expression of the pro-inflammatory gene il-1-β was significantly higher in fish fed FMFO diet than in those fed CP/FOD diet, but comparable to fish fed all other diets. No significant effects were observed for the other tested genes. The results showed a better efficiency in LC-PUFA enrichment of the CP larvae compared to BSF ones, resulting in a higher stimulation of the fish nutrient utilization processes and therefore, a higher growth capacity. Nonetheless, all dipteran larval meal stimulated the immune status whatever the insect species or dietary essential fatty acids

Total replacement of fish meal by enriched-fatty acid Hermetia illucens meal did not substantially affect growth parameters or innate immune status and improved whole body biochemical quality of Nile tilapia juveniles

The study was designed to evaluate the effects of total remplacement of fish meal (FM) and fish oil (FO) by vegetable oil and black soldier fly (BSF) larval meal enriched with fatty acids (FAs) in Nile tilapia juveniles. Fish were fed a FMFO control diet compared to a non-FA-enriched BSF diet (BSF/T0) and diets enriched in linolenic acid-ALA (BSF/T1) or in eicosapentanoic acid-EPA (BSF/T2). After 59 days, the BSF diets did not affect growth except for a decrease by the BSF/T1 diet. However, protein utilization and digestibility were reduced by all the BSF diets. FA-enriched diets did not improve the digestive enzyme activities or immune parameters, while lysozyme and ACH50 values were increased by the BSF/T0 diet. Levels of polyunsaturated FAs in the whole body of fish fed ALA or EPA-enriched BSF diets were comparable to those of FMFO controls. The results demonstrate that BSF meal can totally replace FM without substantially effect on growth or innate immune status. The decrease in fish carcass FA quality induced by the BSF meal can be prevented by a well defined protocol for PUFA enrichment. Nonetheless, investigation of the long-term effects of the BSF meal use during the ongrowing phase is still needed

Teneurs en éléments majeurs, calcium, potassium, magnésium et phosphore et valeur fourragère (énergie - protéines) des pâturages naturels de la sous-région pastorale de l'Ituri (République du Zaïre)

Minerai polyelements composition and nutritive value of pastures from Ituri area. A study of forages chemical composition from Ituri area in Zaire, showed a generally high level of kalium, normal levels of magnesium and some deficiencies of calcium and phosphorus according to the geographic origin (Southern, Middle and Northern) of the samples. The calcium to phosphorus ratio was sufficient, but with a slight excess in the North. The energy concentration was satisfactory in ail the groups of samples, whereas protein defi-ciency was observed in the Middle and the North. The protein-energy ratio was everywhere insufficient. In view of analytical results mineral supplementation formulas were suggested for different localities

Corticosteroids and the stress response in percid fish

International audienc