Miller Kayla A, Mendoza Omarh F, Patience John F, Gabler Nicholas K
Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
The Maschhoffs LLC., Carlyle, IL 62231, USA.
Transl Anim Sci. 2025 Jun 18;9:txaf085. doi: 10.1093/tas/txaf085. eCollection 2025.
In two experimental approaches, this study aimed to evaluate the effects of increasing levels of soybean hulls (SBH) (Exp. 1) and the withdrawal of high SBH from diets prior to marketing (Exp. 2) on growth performance, carcass characteristics, and apparent total tract digestibility (ATTD) of nutrients in grow-finish pigs. In Exp. 1 (n = 12 pens/treatment), 192 pigs (initial BW 21.99 ± 2.75 kg) were fed a corn-soybean meal-based diet containing 0% (0SBH), 7.5% (7.5SBH), 15% (15SBH), or 22.5% (22.5SBH) SBH. In Exp. 2 (n = 15 pens/treatment), 240 pigs (initial BW 26.5 ± 3.03 kg) were fed either 0SBH or 22.5SBH continuously until marketing (-0d) or switched from 22.5SBH to 0SBH either 27 (-27d) or 13 (-13d) days before marketing. Pig body weight (BW) and feed disappearance were measured to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). A balance study was conducted on 32 gilts (n = 8 pigs/treatment) of Exp. 1 beginning on d 56 to determine ATTD of nutrients. Hot carcass weight (HCW), back fat depth (FD), loin depth (LD), and carcass yield were recorded at the processing plant. Data were analyzed using ANOVA, with linear and quadratic contrasts applied for Exp. 1. Pen served as the experimental unit for live performance and carcass characteristics and pig as the experimental unit for ATTD analyses in Exp. 1. In Exp. 1, increasing SBH levels linearly decreased G:F ( < 0.05) and tended to reduce ADG ( = 0.059), without affecting ADFI ( > 0.10), resulting in a 4 kg reduction of final BW ( = 0.067). Inclusion of SBH up to 22.5% decreased HCW, yield, FD, and LD ( < 0.05). In Exp. 2, although 22.5SBH had no effect on ADG and ADFI ( > 0.10), pigs fed 22.5SBH (-27d, -13d, or -0d) had a 6.5% reduction in G:F compared to 0SBH ( < 0.05). Pigs in the -13d and -0d treatment groups had reduced HCW compared to 0SBH ( < 0.05), while yield was reduced by 2% and 5% in the -27d and -0d groups, respectively ( < 0.05). Pigs fed 22.5SBH (-0d) had a 30.7% reduction in FD and a 6.4% reduction in LD compared to 0SBH ( < 0.05). These data suggest that increasing SBH levels in the diet of grow-finish pigs negatively affects feed efficiency, carcass weight and yield, fat and loin depth. However, carcass yield, HCW, FD, and LD loss may recover if pigs are transitioned back to a diet without soybean hulls, depending on the timing of withdrawal before marketing.
在两种实验方法中，本研究旨在评估增加大豆皮（SBH）水平（实验1）以及在上市前从日粮中撤去高含量SBH（实验2）对生长育肥猪生长性能、胴体特性和养分表观全肠道消化率（ATTD）的影响。在实验1（每个处理12个栏）中，192头猪（初始体重21.99±2.75千克）被饲喂以玉米-豆粕为基础的日粮，其中含有0%（0SBH）、7.5%（7.5SBH）、15%（15SBH）或22.5%（22.5SBH）的SBH。在实验2（每个处理15个栏）中，240头猪（初始体重26.5±3.03千克）被连续饲喂0SBH或22.5SBH直至上市（-0天），或者在上市前27天（-27天）或13天（-13天）从22.5SBH转换为0SBH。测量猪的体重（BW）和饲料消耗量以计算平均日增重（ADG）、平均日采食量（ADFI）和饲料效率（G:F）。对实验1的32头后备母猪（每个处理8头猪）从第56天开始进行平衡研究，以确定养分的ATTD。在加工厂记录热胴体重（HCW）、背膘厚（FD）、腰肉厚（LD）和胴体产率。数据采用方差分析进行分析，实验1应用线性和二次对比。在实验1中，栏作为生长性能和胴体特性的实验单位，猪作为ATTD分析的实验单位。在实验1中，增加SBH水平使G:F呈线性下降（P<0.05），并倾向于降低ADG（P=0.059），而不影响ADFI（P>0.10），导致最终体重降低4千克（P=0.067）。添加高达22.5%的SBH会降低HCW、产率、FD和LD（P<0.05）。在实验2中，虽然22.5SBH对ADG和ADFI没有影响（P>0.10），但与0SBH相比，饲喂22.5SBH（-27天、-13天或-0天）的猪G:F降低了6.5%（P<0.05）。与0SBH相比，-13天和-0天处理组的猪HCW降低（P<0.05），而-27天和-0天组的产率分别降低了2%和5%（P<0.05）。与0SBH相比，饲喂22.5SBH（-0天）的猪FD降低了30.7%，LD降低了6.4%（P<0.05）。这些数据表明，在生长育肥猪日粮中增加SBH水平会对饲料效率、胴体重和产率、脂肪和腰肉厚度产生负面影响。然而，如果猪在上市前转回不含大豆皮的日粮，根据撤料时间，胴体产率、HCW、FD和LD的损失可能会恢复。
