Reproductive biology of pingchow tasselmouth loach Vanmanenia pingchowensis in tributary of Foding Mountain in the Middle Wujiang River
LI Zhongli1, MI Xiaoqi1, LEI Hongmei2, RAN Hui1, WANG Cheng1
1.College of Agroforestry Engineering and Planning, Tongren University, Tongren 554300, China; 2.The Administration Bureau of Fodingshan National Nature Reserve, Shiqian 555100, China
Abstract: From January to December 2017 and March, June and September 2018, 262 samples of pingchow tasselmouth loach Vanmaneniapingchowensis were collected from the tributary of Foding Mountain in the Middle Wujiang River (27°15′-27°25′ N,107°56′-108°12′ E) by gillnets and traps with mesh size of 1 cm, and the body length, body weight, net body weight and gonad weight, sex ratio, secondary sexual characters, egg diameter, absolute fecundity, relative fecundity and gonado-somatic index (GSI) were measured for reproductive biology investigation. The results showed that the population of male and female pingchow tasselmouth loach had age from 3+ to 6+ years old, with dominant age of 4+ and 5+. The covariance analysis showed that there was significant difference in body length and body weight relationship between male and female (P<0.05). No conspicuous secondary sexual characters were found in pingchow tasselmouth loach, with sex ratio of female to male=1.53∶1 in spawning season, departing significantly from 1∶1 ratio (P<0.05). Logistic equation revealed that theoretical first maturity was estimated to be at 58.72 mm in body length, 3.83 g in body weight and 2.93 years old in age in female, and at 52.45 mm in body length, 1.99 g in body weight and 3.05 years old, in male. The females had absolute fecundity of 739-2953 eggs, mean value (1629±520)eggs/g, and relative fecundity per net body weight of 150.5-358.4 eggs/g, mean value (250.2±58.5)eggs/g. There were two distinct batches of oocytes in size in the stage Ⅳ ovaries, but only one batch spawned out simultaneously each year. The egg diameter size frequency distribution (changes in GSI) graph displayed the pingchow tasselmouth loach spawned from May to July. The findings indicated the population of pingchow tasselmouth loach showed obvious aging trend and seriously inadequate recruit group, and it is suggested that measurement be taken to protect the existing population including artificial reproduction for enhancement stock by juvenile pingchow tasselmouth loach releasing.
李忠利, 米小其, 雷红梅, 冉辉, 王成. 乌江中游佛顶山平舟原缨口鳅的繁殖生物学特征[J]. 大连海洋大学学报, 2020, 35(4): 551-556.
LI Zhongli, MI Xiaoqi, LEI Hongmei, RAN Hui, WANG Cheng. Reproductive biology of pingchow tasselmouth loach Vanmanenia pingchowensis in tributary of Foding Mountain in the Middle Wujiang River. Journal of Dalian Ocean University, 2020, 35(4): 551-556.
2020, Vol. 35 
