Ritter M J, Ellis M, Hollis G R, McKeith F K, Orellana D G, Van Genugten P, Curtis S E, Schlipf J M
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
J Anim Sci. 2008 Mar;86(3):511-4. doi: 10.2527/jas.2007-0329. Epub 2007 Dec 11.
Four Midwestern packing plants (designated as plants A, B, C, and D) were visited on 53 occasions, and tissue samples were collected postmortem from a total of 2,019 pigs to determine the frequency of the HAL-1843 mutation of the ryanodine receptor gene in dead (DOA), nonambulatory-noninjured (NANI), and normal animals. The sampled pigs came from approximately 130,000 animals from 454 farms and were transported on 861 trailer loads, with an average of 152 pigs/load and an average pig live BW/load of 125 (SD 7.02) kg/pig. Frequency of animals with the HAL-1843 mutation was low, with only 2.7% of the pigs being either homozygous recessives (nn, 0.45%) or carriers (Nn, 2.3%) for the mutation and 97.3% of the pigs being homozygous for the normal allele (NN). The mutation was present in all 3 classes of pig, with 1.8% of normal, 1.8% of NANI, and 4.7% of DOA animals having at least 1 copy. Two of the plants (A and C) had a greater frequency (P < 0.05) of carrier (3.7 and 3.5 vs. 1.1 and 1.0 for plants A and C vs. B and D, respectively) and homozygous recessive (1.0 and 0.9 vs. 0.0 and 0.0, respectively) animals than the others (plants B and D). There was a greater frequency (P < 0.05) of carriers in DOA animals than in the normal or NANI pigs (3.7 vs. 1.7 and 1.5 for DOA vs. normal and NANI, respectively). The 55 pigs that had at least 1 copy of the mutation came from 53 farms; therefore, the mutation was relatively widespread, being present in approximately 11% of the farms sampled. Although the HAL-1843 mutation is still present in commercial pig populations in the United States, its low frequency in DOA and NANI pigs suggests that it is not a major cause of these transport losses.
研究人员对美国中西部地区的4家屠宰加工厂（分别标记为A、B、C和D厂）进行了53次走访，共收集了2019头猪的死后组织样本，以确定死猪（DOA）、非行走非受伤猪（NANI）和正常猪中兰尼碱受体基因HAL - 1843突变的频率。这些抽样猪来自454个农场的约130,000头猪，用861辆拖车运输，平均每车装152头猪，每车猪的平均活体重为125（标准差7.02）千克/头。携带HAL - 1843突变的猪的频率较低，只有2.7%的猪为该突变的纯合隐性个体（nn，0.45%）或携带者（Nn，2.3%），97.3%的猪为正常等位基因的纯合子（NN）。该突变在所有3类猪中均有出现，正常猪中有1.8%、NANI猪中有1.8%、DOA猪中有4.7%至少有1个该突变拷贝。其中两家工厂（A厂和C厂）的携带者（分别为3.7%和3.5%，而B厂和D厂分别为1.1%和1.0%）和纯合隐性个体（分别为1.0%和0.9%，而B厂和D厂分别为0.0%和0.0%）的频率高于其他工厂（B厂和D厂）（P < 0.05）。DOA猪中携带者的频率高于正常猪或NANI猪（P < 0.05）（DOA猪为3.7%，正常猪和NANI猪分别为1.7%和1.5%）。55头至少有1个该突变拷贝的猪来自53个农场；因此，该突变分布相对广泛，在所抽样的农场中约11%的农场存在该突变。虽然HAL - 1843突变在美国商业猪群中仍然存在，但其在DOA猪和NANI猪中的低频率表明它不是这些运输过程中猪死亡的主要原因。
