DOI: 10.3897/arphapreprints.e105690

Authors: Mario Eduardo Sosa, Silvia Cappello-García, Rafael Martínez-García, Suana Camarillo-Coop, Rocío Guerrero-Zárate, Otilio Méndez-Marín, Carlos Alfonso Alvarez-González, Uriel Rodriguez-Estrada

Abstract: Expansion of aquaculture industry is evidently accompanied by an urgent necessity of aquaculture feed production. Traditionally, fish meal (FM) and soybean meal (SBM) have been the primary protein source ingredient in aquaculture diets.  However, over exploitation of these commodities has conducted to their unsustainability. Hence, research of unconventional protein alternatives has emerged. Mushroom meal is one of them. To date, mushroom meals have been investigated when supplemented in low levels in aquaculture diets. Furthermore, effects of diets supplemented with mushroom meals have assessed different parameters such as, haematology, immunity, anti–bacterial & anti–oxidant activities, and heat stress. Present study, is aimed to study the effects of graded levels of dietary pink oyster mushroom (Pleurotus djamor) meal (POMM), in growth, feed efficiency, protein utilization, digestive enzymes activities and whole body proximate composition of Nile tilapia (Oreochromis niloticus) fingerlings. Experimental design included a control diet (POMM0) formulated with soybean meal, as main protein source, and four diets designed with increasing levels of POMM: 25%(POMM25); 50%(POMM50); 75%(POMM75); and 100%(POMM100). Experimental diets and final whole body were submitted to a proximate composition analysis. Growth, feed efficiency, protein utilization, and digestive enzyme activities were assessed.  Compared to POMM0 and POMM25, weight gain (WG), and specific growth rate (SGR), significantly (P

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DOI: 10.3897/arphapreprints.e98663

Authors: Hakan Aksu, Yakup Erdem, Süleyman Özdemir

Abstract: Background. In the Sinop region, many species are caught as non-targets during the target species catching with gill nets. Sardon was used to prevent the bottom creatures (crabs, snails, etc.) climbing these nets used on the ground from climbing. This study was carried out in 13 fishing operations in the inner harbor area of Sinop, from September through November of 2004. Trammel nets were used, which has 32 mm mesh size and target fish species of the fishing gear is red mullet (Mullus barbatus) in the study.Materials and methods. Three net groups were used in the experiments, without sardon (A0) for the control net, multifilament with sardon (A1) and monofilament with sardon (A2) respectively.Results. 65.3% Osteichthyes fish (696 specimens), 16.8% Mollusca (179 specimens), 16.4% was arthropoda (175 specimens) and 1.5% was Chondrichthyes fish (16 specimens) of catch obtained from the operations were form. A total 124 specimens as the target species (red mullet), 398 specimens as bycatch species, and 544 specimens as discarded species were captured sea trials. Catch ratio of A0, A1 and A2 nets were determined 51.88%, 21.58% and 26.55% respectively. 48.38% of the target species, 30.40% of the bycatches and 57.53% of the discarded catch were caught by the A0 net. 25.81% of the target species, 45.23% of the bycatches, and 18.57% of the discard catch were caught with A1 net. 25.81% of the target species, 24.37% of the bycatch and 24.37% of the discarded catch were caught by the A2 net.Conclusions. The results showed that the use of sardon on trammel nets in the Black Sea coastal fisheries caused a slight decrease in target fish catch, but significantly decreased the amount of discarded catch.

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