Dietary inclusion of almond hull on growth performance, nutrient digestibility, faecal microbiome, faecal score, and noxious gas emissions in weaning pigs

Abstract

In a 42-day study, 195 [(Landrace × Yorkshire) × Duroc)] piglets, weighing 6.52 ± 0.59 kg, were randomly assigned to three treatment groups with 13 replicates and 5 pigs (3 barrows and 2 gilts) per pen, and used to evaluate the impact of weaning pig diets containing almond hulls (AHs) on growth performance, nutrient utilization, faecal microbiome, noxious gas emissions, and faecal score. The following dietary treatment groups were applied: basal diet as control, basal diet + 3% AH as TRT1; basal diet + 6% AH as TRT2. At the end of the experiment, the average daily gain and gain-to-feed ratio showed an increasing trend. However, despite these changes, the average daily feed intake remained constant, as did nutrient digestibility, faecal microbiome (Salmonella, Escherichia coli, and Lactobacillus), and faecal score. Among the noxious gases, only NH3 tended to decrease, while other gases (CO2, H2S, methyl mercaptans, acetic acid) remained stable. These findings indicated that the inclusion of AHs in the diet could improve growth performance and reduce NH3 gas production without negative impact on nutrient absorption, microbial populations, and faecal score in weaned piglets.