31Since 1960, the European eel (Anguilla anguilla) has suffered a dramatic reduction in 32 natural stocks. Breeding in captivity is considered an alternative, but obtaining high 33 quality sperm seems basic on this regard. The main objective of this study was to assess 34 the effects of three thermal regimes (two of them variable: T10 and T15; and one of 35 them constant: T20) and three hormonal treatments with different hormones (hCG, 36 hCG rec and PSMG) on the induction of maturation in European eel males. 37In the case of the thermal regimes, our results demonstrated that the onset and 38 progression of spermiation are strongly influenced, and perhaps closely regulated, by 39 water temperature. T20 demonstrated the best results in all the sperm parameters 40 (volume, density, motility, kinetic features, etc) throughout most weeks of treatment, 41 becoming a reliable and productive method for inducing spermiation in this species. In 42 the case of hormonal treatments, the onset and progression of spermiation in European 43 eel males were influenced by the hormone used. In this respect, hCG rec produced the 44 best results in all the sperm parameters including volume, density, motility, kinetic 45 features, etc., throughout most weeks of treatment, thus becoming an effective 46 alternative treatment to the standard hCG treatment used to induce spermiation in eel 47 species. Moreover, hCG rec gave rise to the best economical profitability, making it 48 possible to obtain good quality sperm samples at a lower price than by using the other 49 two hormonal treatments. 50 51

Fish transportation is a common practice on fish farms and is considered to be a stressor that could negatively affect fish health. The objective of this study was to evaluate several physiological responses of stress in jundiá caused by transport at different loading densities. Jundiá juveniles were placed in plastic bags on a mechanical transport simulator for four hours at four different loading densities (75, 150, 250 and 350 g L -1 ) and then transferred to sixteen 80-L plastic boxes for 96 hours after transport. Water samples were collected before and after transport to measure dissolved oxygen, temperature, pH and ammonia levels. Blood samples were taken at departure and arrival, as well as at 24 and 96 hours after transport to monitor cortisol, glucose, ammonia, chloride and hematocrit levels. Water ammonia levels were found to increase gradually as loading densities increased. Plasma ammonia was higher after transport in fish from all treatments. Compared to initial values, substantial increases in plasma cortisol and ammonia levels were detected mainly in those fish submitted to the highest loading density. Blood glucose appeared to be positively influenced by the increase of transport densities. No statistical differences were observed in any of the other blood parameters. The costs in fish culture, as in other animal production systems, must be minimized and fish producers depend on optimal techniques to ensure better profit. Therefore, based on fish survival and the physiological indicators determined in the present study, especially during recovery, the best density at which to transport jundiá in plastic bags for four hours is about 350 g/L.O transporte de peixes é uma prática comum em piscicultura e considerado como um agente estressor que causa efeitos negativos na saúde do peixe. O objetivo deste estudo foi avaliar algumas respostas fisiológicas de estresse no jundiá causadas pelo transporte em densidades diferentes. Juvenis de jundiá foram transportados em sacos plásticos num simulador de transporte por quatro horas em diferentes densidades (75, 150, 250 e 350 g L -1 ) e transferidos para 16 caixas plásticas de 80 L por 96 horas após o transporte. Amostras de água foram coletadas antes e após o transporte para determinações de oxigênio dissolvido, temperatura, pH e amônia. Além dos momentos da saída e da chegada, amostras de sangue foram retiradas 24 e 96 horas após o transporte para monitorar os níveis de cortisol, glicose, amônia, cloreto e hematócrito. A amônia na água aumentou gradualmente acompanhando o aumento das densidades. A amônia plasmática estava elevada após o transporte nos peixes de todos os tratamentos. Comparando com os valores iniciais, aumentos substanciais nos níveis plasmáticos de cortisol e amônia foram registrados principalmente nos peixes submetidos à densidade de transporte mais elevada. Os níveis glicêmicos parecem ter sido influenciados pelo aumento nas densidades de transporte. Não foram registradas diferenças significativas nos demais parâmetros sanguíneos. O cus...

30The development of powerful computerized-assisted sperm analysis software (CASA) 31 has made kinetic studies of spermatozoa possible. This system has been used and 32 validated for several species, but some technical questions have emerged regarding fish 33 sample evaluations (i.e., frame rates, sperm dilution, chamber models, time of analysis, 34 magnification lens, etc). In the present study, we have evaluated the effects of different 35 procedural and biological settings with the aim to measure sperm quality parameters on 36 the European eel correctly. 37The use of different chambers did not affect the sperm motility parameters. However, 38 regarding lens magnification, 10x was the most accurate lens, showing the least 39 variation in the acquired data. Similarly, the frame rate setting resulted in a dramatic 40 effect in some sperm kinetic parameters, primarily in terms of curvilinear velocity, we 41 therefore recommend using the camera's high frame rate setting available. Finally, the 42 reduction in sperm motility over post-activation times suggests that sperm analysis 43 should be performed within the first 60 s after activation of the European eel sperm. In 44 conclusion, some protocol variables of sperm analysis by CASA software can affect the 45 measurement of eel sperm quality parameters, and should be considered before directly 46 comparing results obtained by different laboratories. Moreover, as marine fish species 47show relatively similar features to sperm kinetic parameters, these results could be 48 considered in the evaluation of the motility of sperm from other fish species.

The aim of this study was to evaluate the effect of dietary supplementation with the autochthonous probiotic bacteria Bacillus cereus on growth performance, haematological parameters and survival of tambaqui (Colossoma macropomum). Tambaqui fingerlings (0.94 ± 0.02 g) were fed for 120 days the following diets: basal (without probiotic) and three supplemented diets (4.2 × 10 4 , 3.9 × 10 6 and 3.3 × 10 8 CFU/ g). Growth performance and haematological parameters were evaluated every 30 days. Thereafter, fish were challenged against Aeromonas hydrophila and survival was evaluated. Probiotic B. cereus improved weight and length gains (p < 0.05), and increased neutrophils and thrombocyte counts (p < 0.05) in tambaqui supplemented with 3.9 × 10 6 CFU/g diet. Challenged fish fed unsupplemented diet presented the lowest survival rate (33.4%) while fish fed diets supplemented at 4.2 × 10 4 , 3.9 × 10 6 and 3.3 × 10 8 CFU/g B. cereus had 88.8%, 80.5% and 80.5% relative per cent survival respectively. These results demonstrated that B. cereus supplemented as probiotics to C. macropomum for 120 days improved physiological and haematological responses, leading to enhanced survival in this fish species. K E Y W O R D Samazon, bacterium, fish, haematology, nutrition, performance

O jundiá, Rhamdia quelen, é uma espécie de peixe nativa ainda pouco conhecida cientificamente, mas que tem atraído a atenção de produtores e pesquisadores devido a várias características favoráveis à sua inclusão na lista de peixes criados comercialmente no país. A freqüência alimentar é um fator importante dentro do manejo em piscicultura visando melhorar a eficiência produtiva e reduzir os custos de produção. O presente trabalho testou quatro regimes de arraçoamento (1, 2, 3 e 4 vezes ao dia) em intervalos regulares. Alevinos de jundiá (1,88g) foram estocados em 12 tanques de 4m² por 65 dias. A temperatura da água variou de 23 a 27ºC, durante o período experimental, e os peixes de todos os tratamentos apresentaram índices zootécnicos de desempenho (ganho de peso, conversão alimentar e crescimento especifico) semelhantes. Os peixes alimentados apenas uma vez ao dia tiveram crescimento semelhante àqueles alimentados duas a quatro vezes ao dia. Estes resultados contribuem para a otimização dos recursos necessários à produção comercial do jundiá em cativeiro.

In the hatchery-bred tambaqui Colossoma macropomum, spontaneous semen release does not occur, and hand-stripping produces reduced semen volume. The goal of this work is to evaluate the effects of hormonal induction with carp pituitary extract (CPE) on both qualitative (visual aspect, pH, motility, viability and morphological abnormalities) and quantitative (volume, concentration and number of spermatozoa per ejaculate) traits of tambaqui semen. Eleven males were treated with CPE (induced), and 11 were left untreated as a control (non-induced). All analysed parameters except motility and percentage of viable spermatozoa presented significant differences (p < 0.05) between the induced and non-induced treatments. CPE induction resulted in a 25-fold increase in semen volume and a 10-fold increase in the number of spermatozoa collected. However, both sperm concentration and the frequency of sperm with morphological abnormalities (commonly detached heads or bent tails) were significantly lower in CPE-induced fish. The hormonal induction of tambaqui males with CPE is efficient and positively influences some qualitative and quantitative properties of semen. Additionally, semen collection via gentle abdominal massage occurs more readily in CPE-induced fish.

Seminal features of tambaqui were evaluated after hormonal induction of spermiation with common carp pituitary extract. Seventeen adult (6.1 ± 0.9 kg, 62 ± 6 cm) males were collected from earthen ponds and transported to indoor concrete tanks. Semen was evaluated according to volume, pH, osmolality, motility, concentration, viability, sperm morphometry and morphological abnormalities. The semen of tambaqui was white and milky. The volume was 10.2 ± 5.1 mL at pH 8.0 ± 0.1, and yielded a concentration of 9.1 · 10 9 spermatozoa mL )1 while seminal plasma osmolality was 260 ± 7.3 mOsm kg )1 . The percentage of viable sperm cells was determined with 97.0 ± 2.0% and 87.0 ± 8.0% using an eosin-nigrosin staining and fluorescent live-dead kit (propidium iodide and SYBR-14), respectively. A negative correlation ()0.65) between semen pH and sperm motility was observed suggesting this feature might influence the tambaqui sperm kinetics. Morphometrically the spermatozoa were on average 35.48 ± 1.55 lm long with a roundish head (mean length: 2.73 ± 0.21 lm; mean width: 2.58 ± 0.18 lm; n = 250 spermatozoa), without an acrosome, and presented a long midpiece (2.90 ± 0.52 lm) and flagellum (29.84 ± 1.63 lm). About 15.8% of the spermatozoa carried morphological abnormalities, with bent tail being the most frequent defect (7.81 ± 3.12%). The characterization of tambaqui semen favors the development of more precise and efficient procedures for its analysis and utilization in controlled breeding.

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