Jayme Aparecido Povh

Comparación de protocolos de extracción de ADN con muestras de aleta y larva de peces: extracción modificada con cloruro de sodio

N.M. Lopera-Barrero, J.A. Povh, R.P. Ribeiro, P.C. Gomes, C.B. Jacometo, and T. da Silva Lopes. Comparison of DNA extraction protocols of fi sh fi n and larvae samples: modifi ed salt (NaCl) extraction. 2008. Cien. Inv. Agr. 35(1):77-86. The use of appropriate sampling methods, the type of tissue or sample and the use of viable DNA extraction protocols are critical issues in studies based on PCR. In an attempt to identify a simple, reproducible, inexpensive and non-toxic method for obtaining high quality and quantity genomic DNA from fi sh fi n and larvae samples, modifi ed salt extraction protocol and modifi ed phenol-chloroform extraction protocol were compared. The samples obtained from different fi sh species (Brycon orbignyanus, Piaractus mesopotamicus, Oreochromis niloticus, Leporinus elongatus and Prochilodus lineatus) using salt extraction showed good DNA quality and quantity (DNA/RNA relationship 1.8-2.2). These DNA samples were successfully used in the amplifi cation of RAPD (Random Amplifi ed Polymorphic DNA) and microsatellite molecular markers, demonstrating the same effectiveness of this protocol in comparison with modifi ed phenol-chloroform extraction protocol. This DNA extraction procedure constitutes an alternative and effi cient replacement for previous protocols for improving fi sh molecular studies.

Diversidade genética de pacu do Rio Paranapanema e do estoque de um programa de repovoamento

The objective of this work was to study the genetic diversity of pacu samples from the middle Paranapanema River and from the broodstock used in the stock enhancement program of the Aquaculture and Hydrology Station at the Duke Energy Power Plant, by RAPD marker. Fourteen primers were used to analyze 30 individuals captured in the middle Paranapanema River and 29 individuals from the broodstock. The Shannon genetic diversity index and percentage of polymorphic fragments were higher in individuals captured in the Paranapanema River. Genetic similarity was larger in individuals of the broodstock. Results of analysis of molecular variance showed that the major part of the genetic variation is within the groups (84.2%) and not between them (15.8%). The identity and genetic distance among the groups were 0.9517 and 0.0549, respectively. Moderate genetic differentiation (FST = 0.15) and high number of migrants per generation (Nm = 5.33) were observed between the two groups. The genetic diversity was lower in the broodstock than in fish captured in the middle Paranapanema River.

Comparação do sêmen de Curimbá (Prochilodus lineatus) induzido por extrato de hipófise de frango, coelho ou carpa

Forty eight curimba (Prochilodus lineatus) were selected and hipophysed with broiler chicken hypophysis extract (BCHE), rabbit hypophysis extract (RHE) or carp hypophysis extract (CHE) as a control. The animals were randomly induced with treatments arranged in one factorial of three hormones and three weeks. Animals treated with BCHE, CHE and RHE produced an average of 0.65, 0.45 and 0.20 mL of semen, respectively. Therefore, difference (P 0.05) when compared with males induced with BCHE. Prochilodus lineatus induced with BCHE showed higher progressive spermatic motility (P 0.05) of animals treated with CHE or BCHE. Animals treated with BCHE, RHE or CHE had same spermatic vigor (P>0.05), with an average of 2.75 points. According to these results it is possible to concluded that BCHE showed the same efficiency or it was even better than traditional CHE when used to induced males. However, more research effort with RHE is necessary, particulary with older animals hypophysis.