Department of Animal Science, Aarhus University Campus at Foulum, DK-8830 Tjele, Denmark.
Livestock, SEGES Innovation, DK-8200 Aarhus N, Denmark.
J Anim Sci. 2022 Apr 1;100(4). doi: 10.1093/jas/skac054.
The aim of the study was to investigate whether increased inclusion of sugar beet pulp (SBP) alters retention of fat, protein, and energy when backfat (BF) is restored in early- and mid-gestation. In total, 46 sows were fed one of four treatments with increasing inclusion of SBP with dietary fiber (DF) levels of 119, 152, 185, and 217 g/kg; sows were assigned to one of three feeding strategies (FS; high, medium, and low) depending on BF thickness at mating and again at day 30 for the following month. On days 0, 30, 60, and 108, body weight (BW) and BF thickness were measured, and body pools of protein and fat were estimated using the deuterium technique. On days 30 and 60, urine, feces, and blood samples were collected to quantify metabolites, energy, and N balances. On days 15 and 45, heart rates were recorded to estimate the heat production. At farrowing, total born and weight of the litter were recorded. In early gestation, BW gain (P < 0.01) and body protein retention increased (P < 0.05) with increasing fiber inclusion, while body fat retention increased numerically by 59%. Increase in BF was the greatest for sows fed the high FS, intermediate when fed the medium strategy, and negligible for sows fed the lowest FS. N intake, N loss in feces, and N balance increased linearly, whereas N loss in urine tended to decrease with increasing inclusion of fibers in early gestation. Concomitantly, fecal energy output and energy lost as methane increased linearly (P < 0.001), while energy output in urine declined linearly, and total metabolizable energy intake, therefore, increased from 40.5 MJ ME/d in the low-fiber group to 43.5 mega joule (MJ) metabolizable energy (ME)/d in the high-fiber group (P < 0.001). Changing the metabolizable energy toward more ketogenic energy was expected to favor fat retention rather than protein retention. However, due to increased intake of metabolizable energy and increased N efficiency with increasing fiber inclusion, the sows gained more weight and protein with increasing fiber inclusion. In conclusion, increased feed intake improved both fat and protein retention, whereas increased DF concentration increased protein retention.
本研究旨在探讨在早期和中期恢复背膘（BF）时，增加甜菜浆（SBP）的摄入量是否会改变脂肪、蛋白质和能量的保留。共有 46 头母猪分别饲喂 4 种不同 SBP 添加水平的日粮（SBP 添加量分别为 119、152、185 和 217g/kg，同时含有不同膳食纤维（DF）水平）；母猪根据配种时和随后一个月的第 30 天的 BF 厚度分为 3 种不同的饲喂策略（FS；高、中、低）。在第 0、30、60 和 108 天测量体重（BW）和 BF 厚度，使用氘技术估计体蛋白和体脂肪的蓄积量。在第 30 和 60 天收集尿液、粪便和血液样本，以量化代谢物、能量和氮平衡。在第 15 和 45 天记录心率，以估计产热量。在分娩时，记录总产仔数和仔猪体重。在早期妊娠，BW 增重（P<0.01）和体蛋白保留增加（P<0.05）与纤维添加量呈正相关，而体脂肪保留增加了 59%。高 FS 组母猪的 BF 增加最大，中 FS 组次之，低 FS 组最小。氮摄入量、粪便中氮损失和氮平衡线性增加，而尿液中氮损失有减少的趋势。与此同时，粪便中能量输出和甲烷作为能量损失线性增加（P<0.001），尿液中能量输出线性下降，因此，总可代谢能摄入量从低纤维组的 40.5MJ ME/d 增加到高纤维组的 43.5 兆焦耳（MJ）可代谢能（ME）/d（P<0.001）。向生酮能转化更多可代谢能预计有利于脂肪保留而不是蛋白质保留。然而，由于增加了可代谢能的摄入和增加了纤维添加量时的氮效率，随着纤维添加量的增加，母猪增加了体重和蛋白质的沉积。总之，增加采食量可改善脂肪和蛋白质的保留，而增加 DF 浓度可增加蛋白质的保留。
