Summary The present study was carried out to investigate the number of daily feeding sessions that results in maximum growth of juvenile cobia under laboratory conditions. Groups of eight fish (110 g) were randomly distributed in twenty 500‐L tanks and hand‐fed a commercial diet for 60 days. The same amount of feed was offered daily, divided in 1, 2, 3, four or six meals. None of the parameters associated with growth performance (survival, weight gain, specific growth rate, feed intake, condition factor or size variation) showed any significant differences among treatments. Although under the present conditions feeding frequency had no effect on the growth performance of cobia larger than 110 g, in commercial farming operations where large numbers of fish are kept within a single rearing structure, fish may have aggressive interactions during feeding. Under these conditions, it is difficult to ensure that all cobia are fed to satiation and thus it is usual to provide two or more meals per day. The present results indicate that for an individual cobia the provision of more than one daily meal has no significant effect on growth performance.

This study evaluated the parasite fauna on the gills of spotted goatfish Pseudupeneus maculatus captured in the dry and rainy seasons in the coast of the State of Pernambuco, Brazil. Eight parasite species were identified belonging to the following taxa: Monogenea (Haliotrema caraïbensis, Haliotrema caballeroi and Haliotrema golvani); Crustacea (Rocinela signata, Hamaticolax scutigerulus and Caligidae gen. sp.) and Cestoda (Nybelinia indica and Pseudolacistorhynchus noodti). The most prevalent parasites were: Monogenea (100%), H. scutigerulus (35%), N. indica (11.7%), R. signata (8.3%), Caligidae gen. sp. (3.33%) and P. noodti (0.83%). Values of infestation are compared to other studies, and the uncommon occurrence of Trypanorhyncha on the gills suggests that the spotted goatfish could be an intermediate host for the parasite.Keywords: marine fish, infestation, parasitology. Metazoários parasitos de brânquias do saramunete

Parasitic isopods of fishes usually show wide distribution and low host specificity. This study investigated the occurrence of gill parasites in 120 specimens of spotted goatfish Pseudupeneus maculatus, marine fish of great economic importance for fishery community. The fish were captured monthly in the Coast of Pernambuco State, Northeast Brazil, between October 2012 and September 2013. Eleven isopods were found and identified as Rocinela signata. We observed lower infections in the gills of P. maculatus (prevalence 8.3%, mean intensity 1.6±0.3 and mean abundance 0.1±0.3) when compared to other studies of different host fishes from geographically close locations. This parasite has been reported from a wide variety of fish species, not only in Brazil, but also in the eastern Atlantic and the Pacific oceans. This is the first report of R. signata in spotted goatfish.

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