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Southern black drum (Pogonias courbina) is a species distributed along the western Atlantic Ocean, and it is the largest Sciaenidae observed in the coast of Rio Grande do Sul state, Brazil. However, it is listed as a vulnerable species at The IUCN Red List of Threatened Species™, and their fishing is prohibited. The objective of this study was to determine the sperm characteristics of P. courbina. Sperm samples of five young males (two-year-old fish) were collected through abdominal pressure. The sperm kinetics parameters were sperm motility (MOT) 10.7 ± 5.6%, curvilinear velocity (VCL) 120.07 ± 16.16 mm s ± 1, average path velocity (VAP) 75.64 ± 23.78 mm s ± 1, straight-line velocity (VSL) 62.49 ± 15.83 mm s ± 1, straightness (STR) 83.9 ± 5.3%, wobble (WOB) 61.9 ± 12.7%, beat cross frequency (BCF) 42.981 ± 4.627 Hz and progression (PRG) 1,805.4 ± 564.5 µm. The proportion of normal spermatozoa was 35.6 ± 6.1%. About the abnormalities observed, 22.7% occurred in the tail (short tail = 0.6 ± 0.5%, distally curled tail = 2.4 ± 1.6%, strongly curled tail = 1.9 ± 1.3%, broken tail = 7.9 ± 5.1%, folded tail = 5.5 ± 0.8%, loose tail = 4.4 ± 1.9%); 14.2% occurred in the head (degenerate head = 4.2 ± 1.6%, microcephaly = 1.8 ± 2.5%, loose head = 8.2 ± 2.1%) and 27.5% of the spermatozoa showed cytoplasmatic gouts (proximal gout = 20.0 ± 8.4%, distal gout = 7.5 ± 2.8%). Besides that, a correlation analysis was performed between sperm morphology and kinetics parameters, and the spermatozoa were measured for the morphometric parameters. There was a positive correlation between BCF and normal spermatozoa (r = 0.9269). A negative correlation occurred between BCF and loose head (r = −0.9047); WOB and strongly curled tail (r = −0.8911); and PROG and strongly curled tail (r = −0.9191). The morphometric measures found for the head were length of 2.50 ± 0.21 µm and width of 2.12 ± 0.22 µm, and for the tail it was length of 37.97 ± 2.01 µm. It was possible to verify that the animals have sperm characteristics that indicate reproductive aptitude, but an abnormal behavior on sperm activation and high presence of the cytoplasmic gout abnormality indicates that the animals are not fully mature in their first reproductive season. This work contributes to a better understanding of the P. courbina spermatic parameters, what can be allies to recovery this species population in nature and promote its production in fish farms.

ABSTRACT Was evaluated the pattern of growth among females and males of tambaqui by Gompertz nonlinear regression model. Five traits of economic importance were measured on 145 animals during the three years, totaling 981 morphometric data analyzed. Different curves were adjusted between males and females for body weight, height and head length and only one curve was adjusted to the width and body length. The asymptotic weight (a) and relative growth rate to maturity (k) were different between sexes in animals with ± 5 kg; slaughter weight practiced by a specific niche market, very profitable. However, there was no difference between males and females up to ± 2 kg; slaughter weight established to supply the bigger consumer market. Females showed weight greater than males (± 280 g), which are more suitable for fish farming purposes defined for the niche market to larger animals. In general, males had lower maximum growth rate (8.66 g / day) than females (9.34 g / day), however, reached faster than females, 476 and 486 days growth rate, respectively. The height and length body are the traits that contributed most to the weight at 516 days (P

Objetivo. Caracterizar genéticamente dos lotes y una progenie de Brycon orbignyanus destinados para programas de repoblamiento, utilizando la técnica molecular de RAPD (Random amplified polymorphic DNA). Materiales y métodos. Se analizaron 58 reproductores originarios de dos piscícolas ubicadas en las ciudades de Castillo (A:30 individuos) y Porto Ferreira (C:28 individuos), mantenidos en cautiverio hace seis años en la estación de acuicultura e hidrología de la Duke Energy Internacional (Geração Paranapanema) (São Paulo-Brasil). Treinta larvas de la progenie del lote A (B) también se analizaron. Resultados. Los 14 primers usados produjeron 87 fragmentos de los cuales 70.11% fueron polimórficos. Fueron observadas diferencias (p£0.05) en la frecuencia de 31 fragmentos, con tres exclusivos para el lote A. Los valores de divergencia, distancia e identidad genética mostraron que la diversidad genética del lote A fue mantenida en la progenie y que existe una baja diferenciación entre los lotes de reproductores. El análisis de variancia molecular mostró que la mayor parte de la variación está dentro de cada lote (87.45%) y no entre ellos (12.55%). Este resultado se corroboró con los valores de FST (0.125) y con el dendrograma, que indicaron una moderada diferenciación genética, sin la formación de agrupamientos. Conclusiones. La diversidad genética fue preservada en la progenie debido al manejo eficiente de la reproducción. No hubo una diferenciación genética entre los lotes de reproductores, debido posiblemente a que el origen natural de ambos fue el río Paraná.