King R H, Campbell R G, Smits R J, Morley W C, Ronnfeldt K, Butler K, Dunshea F R
Agriculture Victoria, Victorian Institute of Animal Science, Werribee, Australia.
J Anim Sci. 2000 Oct;78(10):2639-51. doi: 10.2527/2000.78102639x.
Sixty male and 60 female crossbred pigs were allocated to an experiment to investigate the effects of porcine somatotropin (pST) administration (0 or 6 mg/d) and dietary lysine content on growth performance, tissue deposition, and carcass characteristics over the live weight range of 80 to 120 kg. Pigs receiving pST were given diets containing 6.9, 7.8, 8.8, 9.7, 10.6, or 11.5 g lysine/kg, whereas control pigs received diets containing 4.8, 5.8, 6.9, 7.8, 8.8 or 9.7 g lysine/kg. These dietary levels ranged from 0.40 to 0.70 g available lysine/MJ of DE for pST-treated pigs and from 0.28 to 0.58 g available lysine/MJ of DE for control pigs. Pigs were individually housed in pens, and there were five replicates of each treatment. All diets contained 14.5 MJ of DE/kg and were offered for ad libitum consumption to pigs between 80 and 120 kg live weight. Growth rate increased exponentially and food conversion ratio (FCR) decreased exponentially with increasing levels of lysine. In addition, there was a significant sex x pST interaction such that pST reduced the sex difference in FCR. Growth rate was faster in boars than in gilts and was increased by pST at the higher levels of dietary lysine. Similarly, FCR was lower for boars than for gilts and was decreased by pST at the higher dietary lysine levels. The optimum growth rate and FCR were defined as the lysine level at which growth rate and FCR were 95% and 105%, respectively, of the lysine plateau. The optimum growth rate and FCR were achieved at similar dietary lysine contents and were approximately 0.35 and 0.52 g available lysine/MJ of DE for control and pST-treated pigs, respectively. Protein deposition in the carcass increased exponentially with increasing dietary lysine level, was higher in boars than in gilts, and was increased by pST at the higher dietary lysine contents. Sex had no effect on dietary lysine required to maximize protein deposition. The dietary lysine contents required to ensure 95% of plateau protein deposition of 104 and 153 g/d were 0.39 and 0.55 g available lysine/MJ of DE for control and pST-treated pigs, respectively. The increase in lysine requirement with pST seems to be commensurate with the increase in protein deposition.
60头雄性和60头雌性杂交猪被分配到一项实验中，以研究注射猪生长激素（pST）（0或6毫克/天）和日粮赖氨酸含量对80至120千克体重范围内猪的生长性能、组织沉积和胴体特性的影响。接受pST的猪饲喂含6.9、7.8、8.8、9.7、10.6或11.5克赖氨酸/千克的日粮，而对照猪饲喂含4.8、5.8、6.9、7.8、8.8或9.7克赖氨酸/千克的日粮。这些日粮水平对于pST处理的猪而言，有效赖氨酸含量为0.40至0.70克/兆焦消化能，对于对照猪而言为0.28至0.58克/兆焦消化能。猪被单独饲养在栏中，每个处理有五个重复。所有日粮均含14.5兆焦消化能/千克，在猪体重80至120千克时随意采食。随着赖氨酸水平的增加，生长速度呈指数增长，饲料转化率（FCR）呈指数下降。此外，存在显著的性别×pST互作，使得pST降低了FCR的性别差异。公猪的生长速度比小母猪快，且在较高日粮赖氨酸水平下pST可提高生长速度。同样，公猪的FCR低于小母猪，且在较高日粮赖氨酸水平下pST可降低FCR。最佳生长速度和FCR定义为生长速度和FCR分别为赖氨酸平台期的95%和105%时的赖氨酸水平。对照猪和pST处理猪在相似的日粮赖氨酸含量下达到最佳生长速度和FCR，分别约为0.35和0.52克有效赖氨酸/兆焦消化能。胴体中的蛋白质沉积随着日粮赖氨酸水平的增加呈指数增加，公猪高于小母猪，且在较高日粮赖氨酸含量下pST可增加蛋白质沉积。性别对使蛋白质沉积最大化所需的日粮赖氨酸没有影响。对照猪和pST处理猪确保达到104和153克/天的平台期蛋白质沉积量的95%时所需的日粮赖氨酸含量分别为0.39和0.55克有效赖氨酸/兆焦消化能。pST导致的赖氨酸需求量增加似乎与蛋白质沉积的增加相当。
