摘要
南方鲇的雌鱼３－４龄性达成熟，雄鱼２—３龄性达成熟；在此期间，同龄组中已成熟个体的体长、体重、肥满度和成熟系数的平均值均大于未成熟个体。繁殖期为３月中旬至５月中旬，其间，嘉陵江平均水温为１５—２４℃。雌鱼的性腺在６－８月由Ⅵ期退化至Ⅱ期，９至１１月经Ⅲ期发育至Ⅵ期，１２月至来年２月以Ⅳ期性腺状况越冬。雌、雄鱼成熟系数周年曲线均为单峰型，该种鱼为单批产卵类型。产卵场为流水卵石浅滩，水深０．４－１．５ｍ，流速每秒０．７ｍ左右。产卵前雌雄亲鱼有相互激烈追逐、咬斗的发情行为．
Three or four years in famale and 2 or 3 years old in male Silurus meridionalls reached their first sexual maturity. At such ages the average body length, weight, condition factor and maturatlon coefficient of adults are higher than those of the un-mature juvenile of same age for both sexes.The breeding season in the Jialing River lasts from middle March to middle May,when the water temperature ranges from 15℃ to 24℃. From June to August the gonad of stage Ⅳ in the spawned female degenerates into stage Ⅱ.From September to November the gonad develops into stage Ⅲ,and gradually into stage Ⅳ.The gonad remains at stage Ⅳ during winter(from December to February). Only one peak value occurs in the annual cycle of the maturotion coefficient in both sexes, suggesting that this fish spawns only once a year. The spawning sites are located in pebble shoals with a water depth of 0.4-1.5m and a current volocity of about 0.7m/s. During courtship the parental fish display vigorous chasing and snapping behaviours.
出处
《水生生物学报》
CAS
CSCD
北大核心
1996年第1期17-24,98,共8页
Acta Hydrobiologica Sinica
基金
国家自然科学基金
关键词
鱼纲
南方鲇
繁殖
生物学
繁殖周期
产卵条件
Reproduction of fish,sexual maturity,repoductive cycle,environmental conditions for spawning, spawning behaviour, Silurus meridionalis
