为了研究不同盐度下尼罗罗非鱼(Oreochromis niloticus)、萨罗罗非鱼(Sarotherodon melanotheron)和以色列红罗非鱼(Israel red tilapia)幼鱼生长的影响,试验选择尼罗罗非鱼、萨罗罗非鱼和以色列红罗非鱼幼苗各150尾。初始平均体重分别...为了研究不同盐度下尼罗罗非鱼(Oreochromis niloticus)、萨罗罗非鱼(Sarotherodon melanotheron)和以色列红罗非鱼(Israel red tilapia)幼鱼生长的影响,试验选择尼罗罗非鱼、萨罗罗非鱼和以色列红罗非鱼幼苗各150尾。初始平均体重分别为(2.74±0.12)g、(2.69±0.10)g和(2.75±0.11)g。试验共设置5个盐度水平,分别为0‰、10‰、20‰、30‰、40‰。每种鱼每个盐度30尾,并设置3个平行小组。试验为期60 d。结果显示,终末体重和日均增重量以M0(1)组的最高,其生长速度显著的高于其它处理小组(P<0.05)。除处理M10(1)组外,其它均达到极显著水平(P<0.01)。M0(2)、M10(2)、M40(1)和M40(3)的生长速度则显著的慢于其它各个处理小组,其中经过对比,生长速度最快和生长速度最慢相比相差了4倍。成活率和肥满度以M0(2)、M10(2)、M20(2)、M30(2)和M40(2)相对显著高于其它几个处理小组(P<0.05)。在不同盐度梯度下,对3种鱼进行饲养,其终末体重、日均增重、成活率和肥满系数指标均存在显著性差异(P<0.05),说明盐度和罗非鱼品种对罗非鱼的生长速度、成活率和肥满度均有显著影响。在5种盐度下,萨罗罗非鱼的成活率高于以色列红罗非鱼和尼罗罗非鱼,萨罗罗非鱼的肥满系数显著高于尼罗罗非鱼和以色列红罗非鱼,以色列红罗非鱼与尼罗罗非鱼的肥满系数没有显著差异。该研究发现,尼罗罗非鱼和以色列红罗非鱼在低盐度水中生长快,萨罗罗非鱼在高盐度水中生长快。展开更多
Using microsatellite markers with 10 pairs of primers,genetic structure of Oreochromis niloticus,Sarotherodon melanotheron and their hybrids were analyzed.The results suggested that:① Six pairs of primers showed a ri...Using microsatellite markers with 10 pairs of primers,genetic structure of Oreochromis niloticus,Sarotherodon melanotheron and their hybrids were analyzed.The results suggested that:① Six pairs of primers showed a rich polymorphic,which can be used as genetic markers for the genetic diversity study of these tilapias.② The analysis based on the six pairs of primers showed that the average heterozygosity(H)ranged as:O.niloticus ♀× S.melanotheron♂(0.725),S.melanotheron ♀ × O.niloticus ♂(0.692),S.melanotheron(0.537),O.niloticus(0.485).The highest effective numbers of alleles(Ne)existed in O.niloticus♀×S.melanotheron♂(3.79),the lowest existed in S.melanotheron(1.92).The average polymorphism information content(PIC)of 4 tilapias was 0.584,the rank from high to low as,O.niloticus ♀ × S.melanotheron ♂(0.668),S.melanotheron ♀× O.niloticus ♂(0.643),O.niloticus(0.375),S.melanotheron(0.333).③ The fact of enhanced heterozigosity of hybrids suggested that there were the genetic basement of cross breeding in tilapia.展开更多
文摘Using microsatellite markers with 10 pairs of primers,genetic structure of Oreochromis niloticus,Sarotherodon melanotheron and their hybrids were analyzed.The results suggested that:① Six pairs of primers showed a rich polymorphic,which can be used as genetic markers for the genetic diversity study of these tilapias.② The analysis based on the six pairs of primers showed that the average heterozygosity(H)ranged as:O.niloticus ♀× S.melanotheron♂(0.725),S.melanotheron ♀ × O.niloticus ♂(0.692),S.melanotheron(0.537),O.niloticus(0.485).The highest effective numbers of alleles(Ne)existed in O.niloticus♀×S.melanotheron♂(3.79),the lowest existed in S.melanotheron(1.92).The average polymorphism information content(PIC)of 4 tilapias was 0.584,the rank from high to low as,O.niloticus ♀ × S.melanotheron ♂(0.668),S.melanotheron ♀× O.niloticus ♂(0.643),O.niloticus(0.375),S.melanotheron(0.333).③ The fact of enhanced heterozigosity of hybrids suggested that there were the genetic basement of cross breeding in tilapia.