Effect of single-sex or mixed rearing and live weight on performance,technological meat quality and sexual maturity in entire male and female pigs fed raw potato starch

Abstract

The aim of our study was to investigate the effect of rearing system (mixed or single-sex) on performance and carcass quality of entire male and female pigs slaughtered at around 90 or 115 kg live weight. We also studied the combined effect of live weight and dietary supplement of raw potato starch (RPS) on technological meat quality for both sexes, and boar taint compounds in entire male pigs. Furthermore, we investigated pre-slaughter routines (pen-wise or mixing with unfamiliar pigs) and sexual maturity. A total of 408 growing/finishing pigs were included in this two-year study. Performance did not differ significantly between entire male and female pigs irrespective of rearing system, except for daily weight gain in the interval from 90 kg to slaughter. Mixed pigs had significantly higher daily weight gain in this interval than single-sex pigs. Entire male pigs had higher carcass lean meat content than female pigs (1.6 percentage units). Technological meat quality differed only slightly between the sexes. Females reared in mixed pens were sexually more mature than female pigs reared in single-sex pens, and mature females had higher growth rate but lower meat content in carcasses than immature females. In contrast, female contact did not influence sexual maturity of entire male pigs. Mixing entire male pigs with unfamiliar pigs at the abattoir resulted in more damaged skin compared with pen-wise keeping whereas female pigs had almost no visible skin damage. We therefore recommend that entire male pigs are not mixed with unfamiliar pigs during transport and at the abattoir, because of fighting and subsequent skin damage. The levels of skatole in fat were significantly lower in high-weight entire male pigs fed RPS compared to high-weight pigs without RPS. Androstenone levels in fat were high in all groups.     

海南特种野公猪不同世代膻味物质含量及相关性分析

【目的】通过比较不同世代杂交海南特种野公猪F1、F2、F3膻味物质雄烯酮、粪臭素和吲哚含量,及血清性激素水平的差异,揭示公猪膻味物质的变化规律及性激素的变化对膻味物质含量的影响,为选育低膻味性状的公猪提供理论基础。【方法】以12月龄F1、F2、F3不同世代杂交公猪(野猪♂×屯昌猪♀)各18头为研究对象。试验猪空腹12 h,于前腔静脉采取血液样本并提取血清样品,采血后将试验猪屠宰,按照商品猪分割标准从第三和第四颈椎之间的颈部区采集脂肪和肌肉样品。利用(ELISA)试剂盒检测血清样品雄烯酮和性激素水平及脂肪和肌肉样本的雄烯酮含量,采用高效液相色谱法检测血清、脂肪和肌肉样本的粪臭素和吲哚含量。【结果】海南特种野公猪膻味物质雄烯酮、粪臭素和吲哚在血清、脂肪和肌肉组织中非均匀分布。脂肪和肌肉组织中的粪臭素和雄烯酮含量均与血清中的粪臭素和雄烯酮含量存在显著或极显著相关性(P0.05或P0.01),脂肪中粪臭素的含量与血清中粪臭素含量的相关系数最大为0.94。公猪肉品膻味物质粪臭素、雄烯酮和吲哚的沉积量在不同杂交代公猪间存在明显差异,其中雄烯酮的沉积量随着野猪血统的增加而增加,粪臭素的沉积量则随着野猪血统的增加而降低,而吲哚的沉积量不存在随野猪血统的变化规律。性激素水平在不同杂交代野猪间存在明显差异,其中雄激素睾酮水平随着野猪血统的增加而极显著增加(P0.01),而F1公猪的雌二醇水平极显著低于F2和F3公猪(P0.01)。雄烯酮含量均与血清睾酮水平呈极显著正相关(P0.01),而粪臭素含量均与血清睾酮水平呈显著或极显著负相关(P0.01),血清雄烯酮含量与睾酮水平的相关系数最大为0.95。【结论】随着海南特种野公猪血统的增加,睾酮水平和雄烯酮的沉积量显著增加,而粪臭素的沉积量显著降低。因此,海南特种野公猪睾酮水平的变化影响粪臭素和雄烯酮含量的变化。     

A rapid radioimmunological evaluation of the androstenone content in boar fat

Fat from boars containing androstenone is absorbed to a piece of filter paper. The filter paper is then placed in a tube and a buffer containing antibodies against androstenone is added. Following incubation the filter paper is removed, and by measurement of the residual binding capacity for androstenone in the buffer a relative value for androstenone content in the fat is obtained.The coefficient of correlation between the results obtained by this rapid method and the ordinary radioimmunoassay was −0.95.     

组成型雄烷受体与公猪膻味物质代谢关系的研究进展

饲养不去势公猪较去势公猪而言具有很多优势,但导致公猪膻味物质雄烯酮和粪臭素一直是限制其饲养的主要瓶颈。作者综述了组成型雄烷受体对膻味物质雄烯酮和粪臭素代谢关系的研究,为寻求一种较合适的方法减少公猪膻味提供参。