Rostellato R, Bonfatti V, Larzul C, Bidanel J P, Carnier P
J Anim Sci. 2015 Sep;93(9):4267-76. doi: 10.2527/jas.2015-9252.
The aims of this study were to investigate variation in content of androstenone (AND), skatole (SKA), and indole (IND), quantified in adipose tissue of intact male pigs at 160 d of age (105 kg BW) and 220 d of age (155 kg BW), to estimate genetic parameters and to investigate the genetic relationships for AND, SKA, IND, and growth traits. A sample of adipose tissue was collected in vivo, using a biopsy device, from the neck of 500 intact males at the 2 ages and at slaughter from the ham of 100 of the investigated animals. Backfat depth was measured at 220 d of age, whereas BW was recorded at each sampling. Quantification of AND, SKA, and IND was performed by HPLC with fluorescence detection. Estimates of genetic parameters were obtained through Bayesian analyses after logarithmic transformations of original measures. Contents of boar taint compounds (BTC) measured at 220 d were higher than those at 160 d of age. Correlations between contents of BTC in backfat and ham fat ranged from 0.7 (IND) to 0.88 (SKA). Medium-high h were estimated for BTC at both ages, but estimates at 220 d (0.58, 0.60, and 0.69 for AND, SKA, and IND, respectively) were greater than those at 160 d. The genetic correlation between contents at 160 and 220 d of each BTC was positive, but the probability that such estimates were greater than 0.8 was very low, indicating that contents at 160 and 220 d were traits controlled by different genetic backgrounds. Different rankings were observed when breeding values for the content at 160 and 220 d of age were used to rank animals. As a consequence, performance testing programs for BTC should be based preferably on phenotypes measured at 220 d of age. Weak genetic correlations were observed between content of BT compounds and growth traits (BW, backfat depth, and daily gain from 160 to 220 d of age), indicating that selective breeding to reduce the risk of tainted pork is expected to exert trivial effects on growth performance and fat deposition. Results indicate that prevalence of BTC is high in mature and heavy pigs relative to young and light pigs. High heritability; positive genetic correlations between AND, SKA, and IND; and trivial effects on growth traits suggest that reduction of BTC through selective breeding is feasible and exploitable as an alternative to surgical castration also for pigs slaughtered at heavy BW.
本研究的目的是调查160日龄（体重105千克）和220日龄（体重155千克）的完整雄性猪脂肪组织中雄烯酮（AND）、粪臭素（SKA）和吲哚（IND）含量的变化，估计遗传参数，并研究AND、SKA、IND与生长性状之间的遗传关系。使用活检装置在体内从500头完整雄性猪的颈部采集脂肪组织样本，这500头猪分别处于上述两个年龄阶段，另外还从100头被调查动物的后腿肌肉中采集了屠宰时的脂肪组织样本。在220日龄时测量背膘厚度，而每次采样时都记录体重。采用高效液相色谱荧光检测法对AND、SKA和IND进行定量分析。对原始测量值进行对数转换后，通过贝叶斯分析获得遗传参数估计值。220日龄时测得的公猪膻味化合物（BTC）含量高于160日龄时的含量。背膘和后腿肌肉脂肪中BTC含量之间的相关性在0.7（IND）至0.88（SKA）之间。两个年龄阶段的BTC遗传力估计值均为中高水平，但220日龄时的估计值（AND、SKA和IND分别为0.58、0.60和0.69）高于160日龄时的估计值。每个BTC在160日龄和220日龄时含量的遗传相关性为正，但这些估计值大于0.8的概率非常低，这表明160日龄和220日龄时的含量是由不同遗传背景控制的性状。当使用160日龄和220日龄时含量的育种值对动物进行排名时，观察到不同的排名结果。因此，BTC性能测试程序最好基于220日龄时测得的表型。在BT化合物含量与生长性状（体重、背膘厚度以及160至220日龄期间的日增重）之间观察到较弱的遗传相关性，这表明通过选择性育种降低猪肉受污染风险对生长性能和脂肪沉积的影响很小。结果表明，相对于年轻和体重较轻的猪，成熟和体重较重的猪中BTC的发生率较高。高遗传力；AND、SKA和IND之间的正遗传相关性；以及对生长性状的微小影响表明，通过选择性育种降低BTC是可行的，并且作为一种替代手术阉割的方法，对于体重较重时屠宰的猪也是可利用的。
