Este estudo teve como objetivo elaborar croquetes empanados, utilizando a CMS e as aparas do corte em 'V' do filé de tilápia. No mesmo estudo se avaliaram os parâmetros físico-químicos e microbiológicos para as matérias primas e o croquete pronto; realizada também uma análise sensorial. Para a CMS a umidade foi de 79,05%, proteína 14,63%, cinzas 0,87%, extrato etéreo 4,66% e para as aparas, respectivamente,

-The objective of this study was to evaluate the feeding management of pacu juveniles (P. mesopotamicus) under different feeding rates and its relation with productive performance, body composition and hematological characteristics.A total of 300 fish with initial weight of 84.75±4.52 g were distributed in a completely randomized design composed of four treatments (100, 90, 80 and 70% of feed supply) and five repetitions. The amount of feed was stipulated according to the quantity supplied in the treatment until apparent satiation (100%) of the day before. The decrease in the feeding rate to 70% over satiation apparently improves the apparent feed conversion without harming performance, body composition or biochemical and hematological characteristics of pacu juveniles reared in net cages.Key Word: amount of feed, feeding management, intensive aquaculture, native species Revista Brasileira de Zootecnia

One thousand five hundred cachara or tiger shovelnose catfish Pseudoplatystoma fasciatum, obtained from induced reproduction, were used to determine the onset of ovarian differentiation and development and to record the main characteristics of this process. Samples were collected from 0 to 240 days post-fertilization (dpf) and the results classified into stages I-XII. Ovarian formation was histologically detected for the first time when juveniles measured mean ± s.d. 51·5 ± 8·3 mm total length (LT ) at 39-45 dpf (stages I-V), with intense somatic cell proliferation originating in the ovarian cavity. Both LT and age of fish had a positive correlation (P < 0·001) with ovarian differentiation, but LT showed a greater correlation (r(2)  = 0·95) than age (r(2)  = 0·85), especially during the initial stages of development. From stages VI to VII, the ovarian cavity was enlarged and undifferentiated oogonia were present. At stage VIII, small projections formed in the ovarian stroma towards the ventral region of the gonad (future ovarian lamellae) and the basal membrane and differentiated oogonia nests could be seen. At stages IX and X, the germ cells entered meiosis and folliculogenesis was completed by stages XI and XII, which can be considered late in comparison to other Siluriformes. This study has demonstrated that ovarian differentiation in P. fasciatum begins with an intense proliferation of squamous epithelial cells (somatic cells) during the early stages of development and that sex inversion protocols could, thus, be applied successfully before this period. Furthermore, the results have demonstrated that both size and age can influence gonad differentiation and development in this species.

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The effects of a diet supplemented with 5% marine fish oil, 5% refined palm oil, 5% soybean oil, and a combination of the three on reproductive parameters of females Rhamdia quelen was investigated. Spawning was artificially induced to evaluate rates of fertilization, hatching and larvae normality. Fatty acid profiles of the diets, ovaries and oocytes were determined. A higher spawning rate (%) was observed for diets containing fish oil (78.65 ± 3.60) and palm oil (77.15 ± 3.97), followed by oil mix (65.46 ± 4.57). The diet containing soybean oil was associated with significantly lower fertilization (60.14 ± 5.66; P < 0.05) than the palm and fish oil diets. Lower fertilization may be explained by a high level of n-6 fatty acids in the diet, which possibly accelerate the oocyte maturation. Satisfactory fecundity (P > 0.05) were observed for all tested diets, whit 289.77 ± 23.90 (palm oil) until 323.31 ± 38.45 oocytes g-1 body weight (fish oil). The treatments were not shown to influence oocyte size, larval size or rate of larva deformity. Oocyte fatty acid composition was like that of gonads. Docosahexaenoic (DHA; C22:6 n-3) fatty acid was preferentially deposited in ovaries and oocytes. Ratios of n3/n6, DHA/EPA, EPA/ARA, did not affect the reproductive performance of females. Therefore, regarding female reproductive performance, the vegetable lipid sources tested are suitable for being used in R. quelen diet, and palm oil, in particular, is considered an excellent alternative to fish oil.

In this study, sex and age influenced the hematological profiles of Jundiá (Silver Catfish) Rhamdia quelen. Females showed lower levels of hemoglobin, young fish increased lymphocyte counts, and older fish increased hematocrit values. These results indicate that, depending on age and sex, the fish have disparate hematological profiles. For this reason, it is important to consider the sex and age of an R. quelen when examining the impact of environmental and management factors on this species in terms of their hematological profiles. Received May 24, 2015; accepted March 24, 2016.

Summary The aim of this study was to evaluate different post-shock temperatures for tetraploid induction in the yellowtail tetra Astyanax altiparanae. Newly fertilized eggs were divided into four groups, three were submitted to heat shock (40°C for 2 min) at 24 min post-fertilization (mpf) and another group remained without shock (control). Groups submitted to temperature shock were further separated at the following temperatures: 22°C, 26°C and 28°C. Survival among embryonic development was counted and at hatching the ploidy was analyzed by flow cytometry. The results showed that the post-shock temperature affects the parameters analyzed and, therefore, must be considered for optimization of the production of tetraploid in A. altiparanae. Those data are innovative and could be used in future studies of basic biology in this species.

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