Effects of d-aminolevulinic acid, and lactulose supplements in weaning piglets

Abstract Text: δ -aminolevulinic acid (ALA) is a non-protein amino acid that plays a rate limiting role in the process of heme biosynthesis. Lactulose (LAC) is a kind of non-digestible oligosaccharides which has been shown to improve growth performance in weaning pigs through prebiotic actions. This study evaluated the efficacy of ALA, and LAC on growth performance, nutrient digestibility, blood profile, and fecal microbiota in weaned piglets. The study was conducted with one hundred seventy five [(Yorkshire × Landrace) × Duroc] weaned piglets in a 33 d feeding trial, and one of five diets: 1) CON (basal diet, no antibiotic); 2) ALA05 (CON + 0.5 g ALA/kg of diet); 3) ALA10 (CON + 1 g ALA/kg of diet); 4) LAC05 (CON + 0.5 g LAC/kg of diet); 5) LAC10 (CON + 1 g LAC/kg of diet). All pigs were fed diets mixed with 2 g/kg of chromium oxide (Cr₂O₃) to calculate apparent total tract digestibility of nutrients. Non-heparinized tubes and vacuum tubes containing K₃EDTA were used to determine the blood profiles. Fecal sample (1 g) from each pen was diluted with 9 mL of 10 g/L peptone broth to evaluate fecal microbiota. All data were statistically analyzed using the PROC MIXED procedure of SAS. Orthogonal contrasts were used to the effects of treatments. Piglets fed diets with ALA, and LAC had higher feed efficiency (G:F; 0.662, 0.691 vs. 0.624, and 0.675, 0.691 vs. 0.645) compared with piglets fed CON diet during phase 2 (d 6-19), and overall (d 1-33), respectively (P < 0.05). Besides, LAC diets improved ADG (447 vs. 421g; P = 0.037), and G:F (0.691 vs. 0.662; P = 0.024) compared with ALA diets during phase 2. Weaned piglets fed LAC increased dry matter (DM; 83.98 vs. 80.36%, 82.46 vs. 79.52%; d 19, and 33, respectively), and nitrogen (N; 81.70 vs. 77.06; d 33) digestibility compared with CON diet (P < 0.05). Piglets fed with ALA diet increased serum total iron-binding capacity (TIBC), and hemoglobin (Hb) compared with CON diet (714 vs.655 μg/dL, and 8.1 vs. 7.2 g/dL; P < 0.05) on d 33. Piglets fed with the LAC diet increased fecal Lactobacillus (7.58 vs. 7.38 ^log₁₀ cfu/g), and reduced E. coli (6.41 vs. 6.51 ^log₁₀ cfu/g) counts when compared with CON diet on d 33 (P < 0.05). In conclusion, results indicated that dietary supplementation of ALA, and/or LAC improved performance, and/or gut health in weaned piglets. 

Keywords: average daily gain, E. coli, hemoglobin