Peinado J, Serrano M P, Medel P, Fuentetaja A, Mateos G G
1Departamento de Producción Animal, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid, Spain.
Animal. 2011 May;5(7):1131-40. doi: 10.1017/S1751731111000061.
A total of 200 (Landrace × Large White dam × Pietrain × Large White sire) gilts of 50 ± 3 days of age (23.3 ± 1.47 kg BW) were used to investigate the effects of castration (intact gilt, IG v. castrated gilt, CG) and slaughter weight (SW; 106 v. 122 kg BW) on productive performance, carcass and meat quality. Four treatments were arranged factorially and five replicates of 10 pigs each per treatment. Half of the gilts were ovariectomized at 58 days of age (8 days after the beginning of the trial at 29.8 ± 1.64 kg BW), whereas the other half remained intact. The pigs were slaughtered at 106 or 122 kg BW. Meat samples were taken at Musculus longissimus thoracis at the level of the last rib and subcutaneous fat samples were taken at the tail insertion. For the entire experimental period, CG had higher (P < 0.05) BW gain and higher (P < 0.001) backfat and Musculus gluteus medius fat thickness than IG. However, IG had higher (P < 0.05) loin and trimmed primal cut yields than CG. Meat quality was similar for IG and CG but the proportion of linoleic acid in subcutaneous fat was higher (P < 0.001) for IG. Pigs slaughtered at 122 kg BW had higher (P < 0.001) feed intake and poorer feed efficiency than pigs slaughtered at 106 kg BW. An increase in SW improved (P < 0.001) carcass yield but decreased (P < 0.05) trimmed primal cut yield. Meat from pigs slaughtered at the heavier BW was redder (a*; P < 0.001) and had more (P < 0.01) intramuscular fat and less thawing (P < 0.05) and cooking (P < 0.10) loss than meat from pigs slaughtered at the lighter BW. In addition, pigs slaughtered at 122 kg BW had less (P < 0.01) linoleic acid content in subcutaneous fat than pigs slaughtered at 106 kg BW. Castration of gilts and slaughtering at heavier BW are useful practices for the production of heavy pigs destined to the dry-cured industry in which a certain amount of fat in the carcass is required. In contrast, when the carcasses are destined to fresh meat production, IG slaughtered at 106 kg BW is a more efficient alternative.
选用200头（长白猪×大白猪母本×皮特兰猪×大白猪父本）50±3日龄（体重23.3±1.47千克）的后备母猪，研究去势（未去势后备母猪，IG对比去势后备母猪，CG）和屠宰体重（SW；106千克对比122千克体重）对生产性能、胴体和肉质的影响。试验采用析因设计，共4种处理，每种处理10头猪，设5个重复。一半后备母猪在58日龄（试验开始8天后，体重29.8±1.64千克）进行卵巢摘除，另一半保持未去势状态。猪只在体重达106千克或122千克时屠宰。在最后肋骨水平处采集胸最长肌的肉样，在尾根处采集皮下脂肪样。在整个试验期内，CG的体重增加量更高（P<0.05），背膘和臀中肌脂肪厚度更厚（P<0.001），高于IG。然而，IG的腰肉和修整后的主要切块产量更高（P<0.05），高于CG。IG和CG的肉质相似，但IG皮下脂肪中油酸的比例更高（P<0.001）。体重122千克时屠宰的猪采食量更高（P<0.001），饲料效率低于体重106千克时屠宰的猪。屠宰体重增加提高了（P<0.001）胴体产量，但降低了（P<0.05）修整后的主要切块产量。体重较重时屠宰的猪的肉颜色更红（a*；P<0.001），肌内脂肪更多（P<0.01），解冻损失（P<0.05）和烹饪损失（P<0.10）低于体重较轻时屠宰的猪。此外，体重122千克时屠宰的猪皮下脂肪中油酸含量低于体重106千克时屠宰的猪（P<0.01）。后备母猪去势并在较重体重时屠宰，对于生产用于干腌行业的肥猪是有用的做法，因为干腌行业要求胴体含有一定量的脂肪。相反，当胴体用于鲜肉生产时，体重106千克时屠宰的未去势后备母猪是更有效的选择。
