No abstract

This study evaluated the in vitro antiparasitic activity of the essential oils of Lippia alba, L. origanoides and L. sidoides against monogenean parasites of koi carp Cyprinus carpio and its zootechnical performance in net cages. The oils were obtained from the leaves by hydro distillation, and the chemical composition was evaluated via gas chromatography. In vitro assays were performed with each essential oil separately and combined in binary (1:1) and tertiary (1:1:1) mixtures with the Lippia species at 10, 20, 40, 60, 80 and 100 mg L -1 and two control groups (grain alcohol and tank water). To determine zootechnical performance, L. sidoides oil was added to the feed at 0.00 (control), 0.25, 0.50, 0.75 and 1%, in triplicate and with 20 fish per net cage fed for 60 days. The best results in vitro against monogeneans were observed for L. sidoides (40 mg L -1 in 8 min), followed by L. origanoides (40 mg L -1 in 25 min) and L. alba (40 mg L -1 in 4 h). Reductions in weight gain, protein efficiency rate and specific growth rate were observed in diets containing 0.75% of L. sidoides oil in comparison to the control and the 0.25% diet. There were no significant differences in growth, individual mean feed intake, apparent feed conversion and parasitological indices. Based on our results, 0.25% L. sidoides oil showed the best zootechnical performance, but was not effective against koi carp parasites in vivo.

The present study evaluated the effectiveness of Amazonian nut (Bertholletia excelsa) as an alternative source of vegetal protein in tambaqui (Colossom a m acropomum)diet. Performance and physiological status of fish fed for 60 days were evaluated. Four experimental isonitrogenous diets with 36% crude protein were formulated with increasing levels of nut meal (0, 10, 20 and 30%)

This study assessed the effectiveness of three anticoagulants in blood parameters of "cururu" stingrays Potamotrygon cf. histrix. Blood from ten individuals were collected and diluted with anticoagulants EDTA 5% and 10%, heparin 2500 and 5000 UI and sodium citrate 3.2%. A blood sample without anticoagulant was also evaluated. The blood of samples without anticoagulant and with sodium citrate 3.2% coagulated in 20% and 30% of the cases, respectively. Clumps of cells were observed during erythrocyte counting in 30% of samples with EDTA 10%, 40% of samples with heparin 2500 IU and 60% of samples with heparin 5000 IU. No alterations were observed on the erythrogram of "cururu" stingrays with different anticoagulants, the values of plasma glucose were similar in all groups and total protein levels were lower in the samples with EDTA 5% and 10%. The use of sodium citrate 3.2% is not recommended for blood sample conservation of Potamotrygon cf. histrix. stingrays, but anticoagulants did not affect the parameters analyzed in the determination of plasma glucose and erythrogram. Therefore, these results indicate that in order to blood coagulation the samples should be collected directly with any of these anticoagulants concentrations.

The present work reports the length-weight relationships (LWR) for four ornamental fish species from the middle Negro River basin, Amazonas, Brazil. The r 2 value ranged from 0.810 to 0.941 and values of b varied from 2.346 to 3.442. These results represent the first reference on LWR for all four species, based on FishBase.

In the present work, we examined the morphology, dimensions, cytochemical staining reactions and ultrastructure of blood cells from three freshwater stingray species, Potamotrygon wallacei, Potamotrygon motoro and Paratrygon aiereba, living in the waters of the middle Rio Negro basin (Barcelos, Amazonas, Brazil). We identified erythrocytes, erythroblasts, thrombocytes and four types of leukocytes (basophils, heterophils, lymphocytes and monocytes) in the blood of these stingray species. In all the freshwater stingray species studied, the shapes and dimensions of these cells were similar to those of marine elasmobranchs. Positive PAS staining occurred in heterophils and thrombocytes, and weak staining occurred in lymphocytes and monocytes, while metachromasia only occurred in basophils. Positive Sudan Black B staining was observed in thrombocytes and lymphocytes, and weak staining occurred in heterophils. Basophils and heterophils were the only cells with positive bromophenol blue staining, while no peroxidase staining was observed in any of the four leukocyte types. This is the first study to establish the dimensions and cytochemical staining profiles of blood cells in Amazonian stingray species. Because these elasmobranch species are exported as ornamental fish to countries worldwide, this study can contribute to establishing standards for blood constituents that may be helpful in assessing the health and welfare of these fish in artificial systems.

-The objective of this work was to evaluate the effect of feed deprivation and refeeding with diets containing different energy to protein ratios (E/P) on the performance and physiology of juvenile tambaqui (Colossoma macropomum). A 4x2 factorial arrangement with three replicates was used, with four E/P ratios (11.5, 10.5, 9.5, and 8.5 kcal g -1 digestible energy per protein) and two feeding regimens (with and without deprivation), during 60 days. Fish from the food-deprived group were fasted for 14 days and refed from the fifteenth to the sixtieth day, whereas the remaining fish were fed for 60 days. At the end of the experimental period, weight of fish subjected to food deprivation was lower than that of those continuously fed; however, this condition did not influence the physiological parameters analyzed. Tambaqui fed 11.5 kcal g -1 achieved lower final weight than those fed with the other diets, in both regimens. Among the physiological parameters, only plasma protein presented significant increase in fish fed 8.5 kcal g -1 , in both feeding regimens, probably due to the higher dietary protein concentration. These results indicate that fish show a partial compensatory growth, and that 10.5 kcal g -1 can be recommended for the diet of juvenile tambaqui.Index terms: Colossoma macropomum, blood parameters, energy/protein requirement, food restriction. Estratégias alimentares e relação entre energia e proteína sobre o desempenho e a fisiologia de tambaquiResumo -O objetivo deste trabalho foi avaliar o efeito da privação alimentar e da realimentação com dietas contendo diferentes relações entre energia e proteína (E/P) sobre o desempenho e a fisiologia de juvenis de tambaqui (Colossoma macropomum). Utilizou-se arranjo fatorial 4x2 com três repetições, com quatro relações E/P (11,5, 10,5, 9,5 e 8,5 kcal g -1 de energia digestível por proteína) e dois regimes alimentares (com e sem privação), durante 60 dias. Peixes do grupo com privação alimentar permaneceram em jejum por 14 dias e foram realimentados do décimo quinto ao sexagésimo dia, enquanto os demais foram alimentados por 60 dias. Ao final do período experimental, o peso dos peixes submetidos à privação alimentar foi menor do que o dos alimentados continuamente; entretanto, esta condição não influenciou os parâmetros fisiológicos avaliados. Tambaquis alimentados com 11,5 kcal g -1 obtiveram menor peso que os alimentados com as demais dietas, em ambos os regimes. Entre os parâmetros fisiológicos, apenas a proteína plasmática apresentou aumento significativo nos peixes alimentados com 8,5 kcal g -1 , em ambos os regimes alimentares, provavelmente em razão da maior concentração de proteína na dieta. Esses resultados mostram que os peixes apresentam crescimento compensatório parcial em todos os tratamentos, e que 10,5 kcal g -1 pode ser recomendada para a dieta de juvenis de tambaqui.Termos para indexação: Colossoma macropomum, parâmetros sanguíneos, exigência energia/proteína, restrição alimentar.

The determination of hematological values is used to obtain knowledge about the health conditions of animal species. The big-headed Amazon River turtles, (Peltocephalus dumerilianus)are considered one of the least known testudine species concerning their biology and health status. Herein, we determined the hematological and plasma biochemical parameters of 17 (eight males and nine females) adult P. dumerilianusto provide reference interval values for clinically healthy individuals. We collected the blood samples by puncturing the femoral vein using long heparinized hypodermic syringes. Sexual dimorphism for individuals was determined by external observation of the shape of the plastron. The average values obtained for the ten hematological and biochemical parameters analyzed were red blood cell count = 0.32 million µL-1; hematocrit = 20.6 %; hemoglobin = 8.5 g dL-1; mean corpuscular volume = 681.6 fL; mean corpuscular hemoglobin = 267.8 pg; mean corpuscular hemoglobin concentration = 41.9 g dL-1; glucose = 80.6 mg dL-1, total protein = 4.1 g dL-1, triglycerides = 388.9 mg dL-1, and total cholesterol = 79.3 mg dL-1.  Despite the sexual dimorphism evidenced for the species, there was no significant statistical difference between males and females for both hematological and biochemical parameters analyzed herein. Based on these results, the population is considered healthy, with parameter values coinciding with previously reported reference ranges for testudines species in the region. The results obtained in this study can be used for assessing the health status of other Amazonian turtle populations, especially in actions aimed at cultivation strategies, management, and species conservation.