冬季温度刺激对克氏原螯虾繁育的影响

通过加温刺激克氏原螯虾(Procambarus clarkii)雌虾在冬季抱卵,并对卵及幼体在不同水温下的发育过程进行观察。结果显示:经过38 d的加温刺激,在26℃下陆续观察到有虾抱卵,18℃以下未观察到抱卵虾,但该水温能促进雌虾性腺发育。雌虾经加温刺激后所抱卵在18℃,21℃和26℃下均能正常孵化出幼虾。18℃,21℃和26℃下孵化时间分别为(39.67±3.06)d,(28.33±2.52)d和(15.00±2.00)d,孵化所需时间随着温度的提升而减少(P<0.05)。孵化的幼虾经45 d养殖后,在18℃,21℃和26℃下体长分别为(1.90±0.25)cm,(2.73±0.38)cm和(3.78±0.70)cm,体重分别为(0.223±0.100)g,(0.688±0.331)g和(2.145±1.272)g。18℃,21℃水温下的幼虾在此生长阶段为非异速生长(b=3),26℃水温下的幼虾为异速生长(b>3)。在3种温度下,幼体生长速度随温度的升高明显加快(P<0.05)。

Effect of warming up to stimulate Procambarus clarkii to breed in winter

Warming up to stimulate Procambarus clarkii to breed in winter was researched.And the effect of temperature on hatching and larvae development of Procambarus clarkii was investigated.The results showed that the female crayfish could breed by warming up in winter.The female crayfish was oogenetic in the water tank of 26 ℃ temperature after 38 days.The female crayfish wasn’t oogenetic in the water tank of 18 ℃,but the ovary developed.The eggs carried by female crayfish were fertilized and could be hatching normally.The hatching time was(39.67±3.06)d,(28.33±2.52)d and(15.00±2.00)d at the water temperature of 18 ℃,21 ℃ and 26 ℃.After breeding for 45 d,the body length of larvae was(1.90±0.25)cm,(2.73±0.38)cm and(3.78±0.70)cm at the water temperature of 18 ℃,21 ℃ and 26 ℃,and the weight was(0.223±0.100)g,(0.688±0.331)g and(2.145±1.272)g,respectively.Larvae exhibited positive allometric growth(b>3) at 26 ℃ and showed isometric growth at 18 ℃ and 21 ℃(b=3).The hatching speed and larvae growth were positively correlated with temperature in a certain range.