猪遗传改良-付衍39课件

1、猪遗传改良的新趋势、新技术 及对营养需求的新要求 傅 衍1、2 1）PIC中国；2）浙江大学建立紧密的遗传联系全球范围的联合育种测定数量、即数据的大小决定选择强度选择强度决定遗传进展联合育种可以扩大群体, 提高选择强度遗传联系与联合育种配套系对种猪性能要求的多面性性状之间的拮抗性（负相关）众多要求不可能在一头猪、即一个品种上实现兼顾多方面的选育，遗传进展就慢不同的配套系选育目标、选育重点不同选育的效果就更好，遗传进展就更大通过杂交把优点组合到商品猪上众多的要求就有可能在一头猪上实现五元杂交配套系始终是与杂交结合的把在配套系选育中得到提高的性状组合起来 组合效应（针对加性基因作用的性状）杂交优势

2、的利用（对遗传力低的性状）五系杂交可以充分利用四个水平上的杂交优势个体母本父本祖代瘦肉饲料报酬日增重瘦肉饲料报酬日增重产仔数瘦肉量肉质饲料报酬日增重母猪繁殖力瘦肉量肉质母性饲料报酬日增重母猪终身繁殖力1986 - 1990i/t = 1.001991 1995 i/t = 1.141996 2000 i/t = 1.002001 2005 i/t = 1.405%20%27%23%25%30%35%19%16%48%15%37%Updated July 200332%16%18%10%7%17% PIC The better pork people PIC The better pork pe

3、ople PIC The better pork people PIC The better pork people PIC 不断根据市场调整选育方向 数量遗传与生物技术的结合不断增加的分子标记应用生物技术常规生产性能肉质抗病性产仔数个体鉴定数量遗传严格的数量遗传选择 5 年 20 年PIC的选种性能测定是关键标记作用的大小和数量是关键重视肉质的选育pH值颜色健康的遗传改良遗传开发健康遗传越来越重视“Robust” 对环境的敏感性越低越好育种值 Breeding ValuePoor 差 Good好Environment 环境Robust 强健的Specialized 特异的性状 品系 相关系数

4、日增重 A-Cross .99 B-Cross .62背膘 A-Cross .32 B-Cross .70育种值估计中加入杂交猪的信息纯种和杂种的遗传相关 育种值中整合各类信息性能测定的数量大系谱资料全胴体和肉质测定量大分子标记应用多杂交商品猪性能测定及应用信息越多，准确性越高发现基因或标记Marker Discovery 发掘标记DNA 多态性表型现在的选择策略：分子数据在选择中的应用PhenotypicdataEBVMoleculardataSelectionstrategyGenes 基因LD-Markers连锁不平衡标记LE-markers连锁平衡标记Molec. geneticsMo

5、lecular score (MS)统计学UnknownGenes未知基因 表型数据分子数据分子评分(MS)选择策略13进入性能测定后备猪的预选TestingprogramQqQqqqQqqqQQQ测定舍14供体品系 受体品系传统方法基因导入XQQF1QqBackcrossing select Qq vs qq MA foreground selection recover R genome MA background selectionXRBC1Select1qqQqXRXRBCn-1BCnqqqqQqQqXIC1IC1XIC2IC2Improved lineQQQQBCnIntercros

6、sing select QQQqXM1 Q N1M1 Q N1M2 q N2M2 q N215品系 1品系 2F1F1xxF2F2xF3F3xMAS.QTL检测标记效应的估计y = marker genotype + BV + e标记辅助选择Select Molec. Score 分子评分 - BLUP EBV - Index (MS + EBV)标记辅助合成系培育16PIC 应用的标记举例Pork with Sygen MQGenetic MarkerPork without Sygen MQGenetic Marker 肉质（MQ）的遗传标记17 (Rothschild et al. 19

7、91, Short et al. 1997)ESR 头胎 后面的胎次genotype n=4,262 n=4,753 AA 9.4 10.0 AB 9.9 10.5 BB 10.2 10.7 对产活仔数的影响Estrogen Receptor Gene 雌激素受体基因181/12/21/2542466Slide courtesy Max Rothschild C N S I I D P L I YC N S I I N P L I YNH2COOHTransmembranedomainsIIIIIIIVVVIVIIAllele 1 homozygote sequence Allele 2 ho

8、mozygote sequence 293295297299300aMC4R mutation and Test MC4R突变和测验(Kim et al., Mam. Gen. 2000)两个商品群的11与12基因型比较19 PT1生产场的性能表现（UK）20% with pHu 48(lower percent is better)屠宰场大批量肉质测定结果（MQA） All genotypesOnly animals homozygous for favorable allele21First Results: DR2 死亡率 * P0.00122DR2 日增重* P0.00123Trace

9、ability品种鉴定猪肉链的跟踪From Product back to Farm or System24PIC 在育种值估计中使用的标记25PIC遗传标记的开发生产性状抗病肉质品种鉴定 繁殖2003年起每天对计算EBV的有关性状更新对标记效应的估计26育种值估计的新方法（PIC的遗传信息系统）遗传核心场种猪性能胴体与肉质遗传标记商品猪性能全球遗传金字塔交配计划PerformanceCriteria1st Parity2nd Parity3rd Parity # of Observations167415901422Age at 1st Service, days230.5-Weight a

10、t 1st Service, kg160-Estrus Cycle at 1st Service3.4-Back fat at 1st Service, mm16.4-Total Born, pigs, pigs11.811.411.9Born Alive10.810.710.9Farrowing rate, %89.990.191.2Wean-Estrus Interval, d8.135.24.8Retention rate, %-92.082.828例: PIC 母系的选种10%20%20%30%6%10%Lean quantityMeat qualityDisease resistan

11、ceFeed efficiencyGrowth rateSow productivity- pigs born alive- litter weight - weaned- teat number- structural - soundness- growth rate- feed conversion- leanness饲料蛋白对不同品种猪生长的影响日增重(克)饲料蛋白含量Beattie and Henry, Pig International, Jan. 2003消耗能量排泄多余的蛋白质Protein Deposition Key PointsChanges with genetic ty

12、pe and genderAs genetic improvements are made, body composition growth rate and nutrient requirements changeEnvironmental stressors constrain genetic potentialPrecise information needed for growth rate for each phase in order to quantify nutrient requirementsSow NutritionGilt DevelopmentMaximize pro

13、tein growthControlled weight gainAchieve body tissue targetsGestationCritical stages of feedingTissue gain (restoration)LactationMaximize IntakeMinimize tissue lossProposed Effects of Managementon the Prolific SowSow Genetic Potential is expressed to the pointwhere Management becomes limitingGenetic PotentialAnnual Pig Outputor Litter Wean WeightPoor ManagementAverageGoodExcellentFactors:HealthReproductionNutritionEnvironment 遗传与营养的互作营养水平高时性能的差别营养水平低时性能的差