The Reproductive Strategy of the Rare Minnow (Gobiocyprisrarus) in Response to Starvation Stress

摘要

Food abundance plays an important role in the reproduction of fish, especially multiplespawners. Multiple spawners can exhibit various biological strategies when understarvation stress. However, the reproductive strategy used in these fish species remainsunknown. To explore whether rare minnows ( ) prioritizesurvival over current reproduction under starvation conditions, paired adult rare minnowswere starved for 0, 5, 10, 15 d and their spawning activities were recorded. Anatomicaland histological characteristics of unpaired adult rare minnows were examined duringstarvation and following re-feeding. It was found that only 30-70% of paired rare minnowsspawned within 5 d after deprivation of food. Though spawning activity was suppressed bystarvation, rare minnows starved for 0, 5, 10, and 15 d waited 3.89 ± 0.78 d, 5.57 ± 3.36d, 5.83 ± 5.15 d and 6.57 ± 4.50 d, respectively, after re-feeding to resume spawning. Theaverage inter-spawning interval and length until egg production of those starved for 15 dwas 4.60 ± 2.37 d and 139.1 ± 67.9 d, respectively, when they spawned with rhythm, whichwere significantly different from those starved for 0 d ( < 0.05).Anatomical and histological data further revealed that late maturing oocytes degradedafter 8 d of starvation, but the gonadosomatic index recovered to initial levels after 8 dof re-feeding. Thus, reproduction of rare minnows was markedly affected by starvation, butrapidly returned to normal upon re-feeding. These observations demonstrated that pairedrare minnows prioritize survival by channeling energy from the liver and absorbing latematuring oocytes instead of continuing to reproduce under food deprivation condition.