Effects of Palm Kernel Expellers on Growth Performance, Nutrient Digestibility, and Blood Profiles of Weaned Pigs

Feasibility insights into the application of Paenibacillus pabuli E1 in animal feed to eliminate non-starch polysaccharides

The goal of the research was to find alternative protein sources for animal farming that are efficient and cost-effective. The researchers focused on distillers dried grains with solubles (DDGS), a co-product of bioethanol production that is rich in protein but limited in its use as a feed ingredient due to its high non-starch polysaccharides (NSPs) content, particularly for monogastric animals. The analysis of the Paenibacillus pabuli E1 genome revealed the presence of 372 genes related to Carbohydrate-Active enzymes (CAZymes), with 98 of them associated with NSPs degrading enzymes that target cellulose, hemicellulose, and pectin. Additionally, although lignin is not an NSP, two lignin-degrading enzymes were also examined because the presence of lignin alongside NSPs can hinder the catalytic effect of enzymes on NSPs. To confirm the catalytic ability of the degrading enzymes, an in vitro enzyme activity assay was conducted. The results demonstrated that the endoglucanase activity reached 5.37 U/mL, while beta-glucosidase activity was 4.60 U/mL. The filter paper experiments did not detect any reducing sugars. The xylanase and beta-xylosidase activities were measured at 11.05 and 4.16 U/mL, respectively. Furthermore, the pectate lyase and pectin lyase activities were found to be 8.19 and 2.43 U/mL, respectively. The activities of laccase and MnP were determined as 1.87 and 4.30 U/mL, respectively. The researchers also investigated the effect of P. pabuli E1 on the degradation of NSPs through the solid-state fermentation of DDGS. After 240 h of fermentation, the results showed degradation rates of 11.86% for hemicellulose, 11.53% for cellulose, and 8.78% for lignin. Moreover, the crude protein (CP) content of DDGS increased from 26.59% to 30.59%. In conclusion, this study demonstrated that P. pabuli E1 possesses various potential NSPs degrading enzymes that can effectively eliminate NSPs in feed. This process improves the quality and availability of the feed, which is important for animal farming as it seeks alternative protein sources to replace traditional nutrients.

Effects of dietary protease on immune responses of weaned pigs

This experiment was conducted to investigate effects of dietary protease on immune responses of weaned pigs. Weaned pigs (n = 75; 7.06 ± 0.18 kg BW; 28 d old) were randomly assigned to 3 treatments (5 pigs/pen; 5 pens/treatment). Dietary treatments were positive control, a diet with required protein level (PC), negative control, a diet with lower protein level than PC (NC), and NC + 0.02% dietary protease (PRO). The dietary protease used in this experiment was a commercial product containing 75,000 protease units/g derived from Nocardiopsis prasina produced in Bacillus licheniformis. The dietary treatments did not contain any ingredients or additives that may provide antibacterial or physiological effects. Pigs were fed respective dietary treatments for 6 weeks. Blood was collected from randomly selected 2 pigs in each pen on d 1, 3, 7, and 14 after weaning. Measurements were number of white blood cells (WBC), tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), and C-reactive protein (CRP). Pigs fed PRO had lower WBC on d 7 (14.84 vs 20.42 × 10³/μL; p < 0.05) and TNF-α on d 7 (618 vs 889 pg/mL; p = 0.085) and 14 (437 vs 576 pg/mL; p = 0.069) than those fed NC, but there were no differences on WBC and TNF-α between PC and PRO. Pigs fed PRO had lower TGF-β1 on d 3 (630 vs. 1,588 and 1,396 pg/mL; p < 0.05) than those fed PC and NC. However, no differences were found on CRP among dietary treatments. In conclusion, addition of dietary protease reduced inflammatory immune responses of weaned pigs.

Effects of complex probiotic supplementation in growing pig diets with and without palm kernel expellers on growth performance, nutrient digestibility, blood parameters, fecal microbial shedding and noxious gas emission

In Experiment 1, a total of 100 growing pigs (Duroc × [Landrace × Yorkshire]) with an average initial body weight (BW) of 24.88 ± 1.57 kg were randomly allotted to 2 × 2 factorial arrangement with two concentrations of palm kernel expellers (PKE) in diets at 0% or 10%, and two concentrations of supplemental probiotics at 0 or 6.0 × 10⁷  colony-forming units/kg. There were five replicate pens per treatment with five pigs per pen. In Experiment 2, eight barrows with average initial BW of 25.78 ± 0.19 kg were allotted to a replicated 4 × 4 Latin square design with four diets and four periods per square. Four experimental diets were the same as Experiment 1. In Experiment 1, dietary probiotic supplementation improved (P < 0.05) the average daily gain (ADG), nutrient digestibility and the fecal Lactobacillus counts. Furthermore, interactive effects (P < 0.05) between PKE and probiotics were observed on ADG and growth-to-feed ratio. In Experiment 2, an interactive effect (P < 0.05) of PKE and probiotics was observed in apparent ileal digestibility of nitrogen and some amino acids. In conclusion, dietary probiotics did not improve PKE utilization and the use of probiotics in non-PKE-containing diet was more favorable than in PKE-containing diet.

Effects of mannan level and β-mannanase supplementation on growth performance, apparent total tract digestibility and blood metabolites of growing pigs

The exogenous enzymes are less consistent in their effects as their beneficial effects depend upon the types and level non-starch polysaccharides (NSP) present in the diets. Therefore, exogenous enzymes should be selected on the basis of types and amount of the NSP in the pig diets. The objectives of the present experiments were to investigate the effects of dietary level of mannan and β-mannanase supplementation on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, and blood metabolites of growing pigs. In Exp. 1, 96 barrows were randomly allotted to four treatments on the basis of BW. There were four replicates in each treatment with six pigs per replicate. The dietary treatments were a corn-soybean meal (SBM)-based control diet and three other diets consisted of the control diet supplemented with 400, 800 or 1600 U of β-mannanase/kg diet. The final BW, average daily gain (ADG) and blood glucose increased (linear, P0.05) on the concentrations of blood total cholesterol, triacylglycerides and blood urea nitrogen. These results indicate that supplementation of β-mannanase to low- or high-mannan diets have potential to improve the performance of growing pigs. In addition, palm kernel meal may partially replace corn and SBM without reducing pig performance if β-mannanase is added to diet.