牙鲆抗迟缓爱德华氏菌病家系的继代选育与早期速生家系筛选

Screening of Disease-Resistant and Fast Growing Families and Subculture Breeding for Resistance Against Edwardsiella tarda in Japanese Flounder (Paralichthys olivaceus)

中文关键词: 牙鲆  迟缓爱德华氏菌  F4代家系  抗病

英文关键词: Paralichthys olivaceus  Edwardsiella tarda  F4 generation family  Disease-resistance

中文摘要:

      迟缓爱德华氏菌(Edwardsiella tarda)是牙鲆(Paralichthys olivaceus)的主要致病菌之一，严重影响牙鲆养殖业的可持续发展。本研究主要以2012、2013和2014年选育的优质抗病牙鲆家系为亲本，于2016年建立和培育了28个牙鲆家系，包括F3代家系4个、F4代家系23个和对照家系1个。经过60 d的鱼苗早期生长性能测定和迟缓爱德华氏菌人工攻毒感染实验，筛选得到7个高抗病力(攻毒感染存活率>66%)的家系，包括1个高抗病、速生家系(F1639)，攻毒存活率达77.23%，比28个家系的平均值高32.75%，全长日增长率达到0.174 cm/d，比28个家系的均值高0.023 cm/d。该家系亲本源自2007年[F0750，抗鳗弧菌(Vibrio anguillarum)病家系]、2009年(F0927，抗鳗弧菌病家系)和2014年(F1421，抗迟缓爱德华氏菌家系)选育的抗病力强家系。历代攻毒感染实验的结果显示，选育的牙鲆家系抗病力逐代提高，说明通过家系选育(同胞选择)，能够有效提高选育后代的抗病力。本研究进一步证明，家系选育是培育鱼类抗病优良品种的有效途径，为进一步培育出生长更快、抗病力更强的牙鲆新品种奠定了良好的基础，也为牙鲆对爱德华氏菌抗病性能的遗传解析和抗病机理研究提供了良好的遗传材料，对其他鱼类抗病良种选育具有重要指导作用和应用价值。

英文摘要:

      Edwardsiella tarda is one of the pathogenic bacteria of Paralichthys olivaceus that seriously affects the sustainable development of flounder aquaculture. In the present study, we used the family of high-quality flounder developed in 2012, 2013, and 2014 as the parents, and developed 28 flounder families in 2016, including 4 F3 generation families, 23 F4 generation families, and control family. After 60 days of growth trait assay and artificial bacterial infection experiments, seven families with strong resistance to disease (survival rate > 66%) were screened. F1639 was screened as the F4 generation family with enhanced disease resistance and fast growth rate. Furthermore, its survival rate was 77.23%, which was 32.75% higher than that of the average of 28 families. The daily growth rate was 0.174 cm/d, which was 0.023 cm/d higher than that of the other 28 families. F1639 was derived from the 2007 (F0750, resistant to Vibrio anguillarum family), 2009 (F0927, resistant to V. anguillarum family), and 2014 (F1421, resistant to E. tarda family) families. The results showed that the disease resistance of the breeding families improved. Furthermore, the breeding ability of the offspring can be improved by the breeding of the family (the selection of compatriots). The present study has laid a foundation for breeding new variety of Japanese flounder with higher disease resistance and growth rate. Furthermore, it has important potential application in the genetic breeding for disease-resistant and fast growth stock in other fish species.