Niyonsaba Aaron, Jin Xing Hao, Kim Yoo Yong
Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Science, Seoul National University, Seoul 08826, Korea.
Anim Biosci. 2023 Oct;36(10):1584-1595. doi: 10.5713/ab.23.0155. Epub 2023 Jun 26.
This study was conducted to evaluate the effect of a low-protein diet on growth performance, carcass traits, nutrient digestibility, blood profiles, and odor emissions in growing-finishing pigs.
A total of 126 crossbred pigs ([Yorkshire×Landrace]×Duroc) with an average body weight (BW) of 38.56±0.53 kg were used for a 14-week feeding trial. Experimental pigs were allotted to one of 6 treatments in 3 replicates of 7 pigs per pen in a randomized complete block design. Pigs were fed each treatment diet with different levels of crude protein (CP). Phase 1 (early growing): 14%, 15%, 16%, 17%, 18%, 19%; phase 2 (late growing): 13%, 14%, 15%, 16%, 17%, 18%; phase 3 (early finishing): 12%, 13%, 14%, 15%, 16%, 17%; phase 4 (late finishing): 11%, 12%, 13%, 14%, 15%, 16%. All experimental diets in each phase were contained the same concentration of lysine (Lys), methionine (Met), threonine (Thr), and tryptophan (Trp).
Over the entire experimental period, there was no significant difference in BW, average daily feed intake, and gain-to-feed ratio among all treatments (p>0.05), but a quadratic effect (p = 0.04) was observed in average daily gain (ADG) during the late finishing phase with higher ADG in Group D. Blood urea nitrogen concentration linearly increased with an increase in dietary CP levels (p<0.01). Regarding nutrient digestibility, excreted nitrogen in urine and feces and nitrogen retention linearly increased as the CP level increased (p<0.01). A linear effect was observed with increasing CP levels in amines, ammonia, and hydrogen sulfide in odor emissions (p<0.01). No significant effects were observed in the measurements of carcass traits and meat characteristics (p>0.05).
In phase feeding, reducing the CP level to 14% in early-growing pigs, 13% in late-growing pigs, 12% in early-finishing pigs, and 11% in late-finishing pigs is recommended.
本研究旨在评估低蛋白日粮对生长育肥猪生长性能、胴体性状、养分消化率、血液指标和气味排放的影响。
选用126头平均体重（BW）为38.56±0.53 kg的杂交猪（[约克夏×长白]×杜洛克）进行为期14周的饲养试验。试验猪采用随机完全区组设计，分为6个处理组，每个处理组3个重复，每个重复7头猪，每栏饲养。给猪饲喂不同粗蛋白（CP）水平的各处理日粮。第1阶段（生长前期）：14%、15%、16%、17%、18%、19%；第2阶段（生长后期）：13%、14%、15%、16%、17%、18%；第3阶段（育肥前期）：12%、13%、14%、15%、16%、17%；第4阶段（育肥后期）：11%、12%、13%、14%、15%、16%。各阶段所有试验日粮的赖氨酸（Lys）、蛋氨酸（Met）、苏氨酸（Thr）和色氨酸（Trp）浓度相同。
在整个试验期内，各处理组的体重、平均日采食量和料重比均无显著差异（p>0.05），但在育肥后期，平均日增重（ADG）观察到二次效应（p = 0.04），D组ADG较高。血液尿素氮浓度随日粮CP水平的升高呈线性增加（p<0.01）。关于养分消化率，随着CP水平的升高，尿液和粪便中的排泄氮以及氮保留量呈线性增加（p<0.01）。随着CP水平的升高，气味排放中的胺、氨和硫化氢呈线性效应（p<0.01）。胴体性状和肉质测定未观察到显著影响（p>0.05）。
在阶段饲养中，建议生长前期猪的CP水平降至14%，生长后期猪降至13%，育肥前期猪降至12%，育肥后期猪降至11%。
