Reproductive cycle and size at first sexual maturity of the white shrimp Penaeus schmitti (Burkenroad, 1936) in northeastern Brazil
ABSTRACT The present study aimed to investigate the reproductive cycle and size at first maturity of Penaeus schmitti through a macro and microscopic approach. Between August 2011 and July 2012, 1169 specimens were collected by an artisanal fishing vessel operating a double trawl off the coast of Pernambuco, northeast Brazil. The total proportion of males (42%) was significantly lower than females (58%), corresponding to the sex ratio of 1:1.38. The total body length at first ovarian maturation (TL50) in females was estimated at 14.2 cm. The ovarian development was divided into four distinct stages based on histological characteristics and visual observations. This is the first reported occurrence of vitellogenic oocytes in the spent stage of P. schmitti, indicating a rapid ovarian maturation after spawning. Furthermore, the frequency of maturation stages, diameter of oocytes and gonadosomatic index were distributed homogeneously throughout the study period, reinforce a continuous reproductive cycle for P. schmitti population in northeastern Brazil.