Fadlaoui S., Melhaoui M. 2023. Breeding cycle and seasonal biochemical changes in the gonads of the North African freshwater crab Potamon algeriense (Bott, 1967) (Brachyura: Potamidae) // Invertebrate Zoology. Vol.20. No.1: 97–107 [in English].
Laboratory of Water, Environment, and Sustainable Development, Department of Biology, Faculty of Sciences, Mohamed First University, Blvd Mohamed VI, PB 717, 60000, Oujda, Morocco. E-mail: email@example.com
ABSTRACT: The present study aims to determine, for the first time, the annual breeding cycle and the biochemical changes in the gonads of the North African freshwater crab, Potamon algeriense (Bott, 1967). Monthly collections were carried out by hand, from October 2018 to September 2019 in Oued Zegzel, a mountain stream in the Northeast of Morocco. The gonad size reached high values in the dry season (June to September) showing the maximum breeding activity during these months. By June, the gonads of most of the individuals attained full maturity where the spawning began. Spawning terminated by the end of September then the gonads entered a quiescent period. Histological observations of the gonads revealed that the ripening of the gonads started during March and extended up to May. During the maturation of the gonads, protein, fat, and glycogen contents were high, whereas, all the concentrations fell considerably reaching the minimum values at the end of the spawning period.
KEY WORDS: breeding cycle, freshwater crabs, histology, gonadosomatic index (GSI), reproduction, spawning.