Enfält A C, Lundström K, Karlsson A, Hansson I
Department of Food Science, Swedish University of Agricultural Sciences, Uppsala.
J Anim Sci. 1997 Nov;75(11):2924-35. doi: 10.2527/1997.75112924x.
The frequency of the dominant RN- allele (Rendement Napole) was estimated in purebred Swedish Hampshire pigs (n = 208) by using the estimated glycogen content in the longissimus muscle at slaughter (glycolytic potential; GP). Carriers (n = 177) and noncarriers (n = 31) of the RN- allele were compared with purebred Swedish Yorkshire (Y, n = 208) and Swedish Landrace (L, n = 114) pigs with respect to GP and carcass composition. Technological meat quality was compared between the RN phenotypes from the Hampshire breed and Yorkshire pigs. The distribution of GP deviated from a normal distribution in all three breeds. Hampshire pigs with GP > or = 183 micromol lactate equivalents per gram wet weight were regarded as carriers of the RN- allele (RN-/RN-, or RN-/rn+), and those constituted 85% of all Hampshire pigs evaluated, giving a frequency of .61 for the dominant allele (RN-). The RN- carriers had higher GP than noncarriers, Landrace, and Yorkshire pigs, but noncarriers and Landrace did not differ regarding GP. The two RN phenotypes did not differ in carcass composition, but the carriers were leaner than Landrace and Yorkshire, with larger proportions of meat plus bone in ham and back. Noncarriers and Yorkshire did not differ in leanness, but both these groups were leaner than Landrace. The RN- carriers had lower Napole yield (cured cooked muscle) and higher drip loss than noncarriers and Yorkshire, but in comparison with noncarriers they also had lower shear force values. In conclusion, the frequency of the RN- allele is high in purebred Swedish Hampshire. Most of the effects of the allele on technological meat quality (i.e., ultimate pH, water-holding capacity, and technological yield) found in crossbred pigs seem also to be consistent for purebred pigs. However, the RN- allele exerted less influence on meat content in purebred pigs.
通过测定屠宰时背最长肌中的糖原含量（糖酵解潜力；GP），对208头纯种瑞典汉普夏猪的显性RN-等位基因（Rendement Napole）频率进行了估计。将RN-等位基因的携带者（n = 177）和非携带者（n = 31）与纯种瑞典约克夏猪（Y，n = 208）和瑞典长白猪（L，n = 114）在GP和胴体组成方面进行了比较。对汉普夏品种和约克夏猪的RN表型之间的加工肉质进行了比较。在所有三个品种中，GP的分布均偏离正态分布。GP≥183微摩尔乳酸当量/克湿重的汉普夏猪被视为RN-等位基因的携带者（RN-/RN-，或RN-/rn+），这些猪占所有评估汉普夏猪的85%，显性等位基因（RN-）的频率为0.61。RN-携带者的GP高于非携带者、长白猪和约克夏猪，但非携带者和长白猪在GP方面没有差异。两种RN表型在胴体组成上没有差异，但携带者比长白猪和约克夏猪更瘦，火腿和背部的肉加骨比例更大。非携带者和约克夏猪在瘦肉率上没有差异，但这两组都比长白猪瘦。RN-携带者的Napole产量（腌制熟肉）低于非携带者和约克夏猪，滴水损失高于非携带者和约克夏猪，但与非携带者相比，其剪切力值也较低。总之，纯种瑞典汉普夏猪中RN-等位基因的频率较高。杂种猪中该等位基因对加工肉质（即最终pH值、持水能力和加工产量）的大多数影响似乎在纯种猪中也一致。然而，RN-等位基因对纯种猪肉含量的影响较小。
