Maternal effects on fecundity and egg quality of the Patagonian stock of Argentine hake (Merluccius hubbsi)

MACCHI, G. J.; LEONARDUZZI, E.; DIAZ, M. V.; RENZI, M.; RODRIGUES, K.

FISHERY BULLETIN

NATL MARINE FISHERIES SERVICE SCIENTIFIC PUBL OFFICE

Lugar: US; Año: 2013 vol. 111 p. 325 - 336

0090-0656

The influence of age, size and condition of spawning females on fecundity and oocyte quality were analyzed for the Patagonian stock of Merluccius hubbsi. Samples of mature females were collected in the spawning area during two research surveys in January 2010 and 2011, during the peak of the reproductive season. Batch fecundity (BF) ranged between 40,500 (29 cm total length [TL]) and 2,550,000 (95 cm TL) hydrated oocytes, and was positively correlated with total length, gutted weight, age, hepatosomatic index (HSI) and the relative condition factor (Kn). Relative fecundity ranged between 85 and 1040 hydrated oocytes g-1 and showed significant positive relationships with gutted weight, HSI and Kn; however coefficients of determination were low for all regressions. Dry weights of samples of 100 hydrated oocytes ranged between 1.8 and 3.95 mg and were positively correlated with all variables analyzed, including batch and relative fecundity. Multiple regression models using the morpho-physiological characteristics of females supported maternal influences on fecundity and egg weights. Larger individuals had better somatic and egg condition, mainly revealed by higher HSI and hydrated oocytes with larger oil droplets. These results would be associated with the fact that larger females showed higher feeding activity during the spawning season in comparison with young individuals.