Comportamento social de machos e suas implicações na reprodução e larvicultura do ciclídeo africano Aulonocara Nyassae

Abstract

The aims of the present work were to evaluate behavior, evaluate the influence of male social status on sperm quality, hematological parameters and serum biochemistry, organosomatic indexes, growth and reproductive performance of males and females, and progeny larviculture of A. nyassae. Experiment 1 was divided into: Phase 1 - establishment of social status among males. During this period, males were classified according to social status: dominant, sub-dominant and submissive; Phase 2 - reproduction, four males of each social status were selected and were allocated with females and; Phase 3 - individualization of males (removal of females). In experiment 2, in the pre-experimental phase, four aquariums, with three males in each, were observed for 48 h and videos of 10 min were recorded twice a day and an ethogram was created about social status definition. The experimental phase lasted 66 days, with one male per aquarium, each of the males of the three social statuses was allocated with three females, with four replications. The animals were filmed for 10 min, twice a day, for 5 days, every 30 days. An ethogram on the reproductive behavior of males and females was generated. In Phase 1, only one dominant male was detected in a group of 10 animals. The final weight (FW) was higher for dominant fish. The sperm concentration, motility rate (MOT), Amplitude of lateral head movement (ALH), linearity (LIN), straightness (STR), wobble (WOB) and beat-cross frequency (BCF) did not show statistical difference between dominant and subdominant fish. Curvilinear velocity (VCL), Straight-line velocity (VSL) and Average path velocity (VAP) were higher for subdominant fish. Motility time was higher for the dominant male. In phase 2, the male performance was higher for dominant and subdominant. MOT and VAP were higher for dominant males. ALH, LIN, STR, WOB and BCF were higher for subdominant males. The social status of males did not influence the growth and reproductive variables of the females. In phase 3, the male performance was higher for dominant and subdominant fish. MOT, VCL, VSL, VAP and WOB were superior to dominant and subdominant males. LIN and STR were superior for subdominant males. BCF was superior to dominant. In experiment 2, locomotion was more abundant for subdominant and submissive males (P < 0.05). For males, courtship was greater in dominant and subdominant males and in females with dominant males (P < 0.05). Locomotion was higher in females with dominant and subdominant males (P < 0.05). The survival of females with subdominant males was lower (P < 0.05). FW, average weight gain (AWG), glucose (GLU), triglycerides (TG), viscerosomatic indexes (VSI) and hepatosomatic indexes (HIS) for males; average total length (ATL), average length gain ALG, Fulton’s condiction factor (K), specific growth rate (SGR), hemoglobin (Hb), GLU, total cholesterol (TC), FW and AWG for females and, for the progeny, the average egg production, hatching rate, average of produced larvae, final average weight of the larvae and the average length end of the larvae were higher for dominant (P < 0.05). In males, SGR and TC and, in female triglycerides (TG), total plasma protein (TPP), gonadosomatic index (GSI), intraperitoneal fat index (IPFI), HIS and VSI were higher for submissives (P < 0.05). However, ALG, GSI, IPFI, Hb and TPP were higher for subdominant and submissive males (P < 0.05). K was higher for dominant and submissive males (P < 0.05). Therefore, the social status of males influences the growth, hemoglobin, blood biochemistry, sperm quality, reproductive capacity of males and females and, progeny quality of A. nyassae.