Intestinal microbiota modulation and improved growth in pigs with post-weaning antibiotic and ZnO supplementation but only subtle microbiota effects with Bacillus altitudinis.

The objective was to evaluate the effect of dietary Bacillus altitudinis spore supplementation during day (D)0-28 post-weaning (PW) and/or D29-56 PW compared with antibiotic and zinc oxide (AB + ZnO) supplementation on pig growth and gut microbiota. Eighty piglets were selected at weaning and randomly assigned to one of five dietary treatments: (1) negative control (Con/Con); (2) probiotic spores from D29-56 PW (Con/Pro); (3) probiotic spores from D0-28 PW (Pro/Con); (4) probiotic spores from D0-56 PW (Pro/Pro) and (5) AB + ZnO from D0-28 PW. Overall, compared with the AB + ZnO group, the Pro/Con group had lower body weight, average daily gain and feed intake and the Pro/Pro group tended to have lower daily gain and feed intake. However, none of these parameters differed between any of the probiotic-treated groups and the Con/Con group. Overall, AB + ZnO-supplemented pigs had higher Bacteroidaceae and Prevotellaceae and lower Lactobacillaceae and Spirochaetaceae abundance compared to the Con/Con group, which may help to explain improvements in growth between D15-28 PW. The butyrate-producing genera Agathobacter, Faecalibacterium and Roseburia were more abundant in the Pro/Con group compared with the Con/Con group on D35 PW. Thus, whilst supplementation with B. altitudinis did not enhance pig growth performance, it did have a subtle, albeit potentially beneficial, impact on the intestinal microbiota.

Porcine Digestible Peptides (PDP) in Weanling Diets Regulates the Expression of Genes Involved in Gut Barrier Function, Immune Response and Nutrient Transport in Nursery Pigs.

This study was conducted to investigate the effects of dietary supplementation of porcine digestible peptides (PDP), spray-dried plasma (SDP), or a combination of both, on growth performance and the expression of genes related to intestinal function of weaned pigs. A total of 180 piglets (trial 1) and 198 piglets (trial 2) were used to evaluate the partial substitution of soybean ingredients with 2% SDP or 2% PDP (trial 1), and with 3% SDP or the combination of 1% SDP and 2% PDP (SDP-PDP; trial 2) during the pre-starter period (0-14 days). The gene expression of 56 genes was quantified in a qPCR platform in jejunum and ileum samples obtained from piglets 14 d after weaning (trial 2). Piglets fed SDP, PDP and SDP-PDP had a higher body weight (BW), average daily gain (ADG) and feed efficiency (G:F) than the soybean control on day 14 (p < 0.05). In addition, the combination of SDP and PDP upregulated ten genes in jejunum samples (p < 0.05) related to intestinal function. More research is needed to confirm that gene expression upregulation by PDP in combination with SDP has an impact on intestinal function and to elucidate its underlying mechanisms.

Effect of Feeding Glycerin on Ruminal Environment and In Situ Degradability of Feedstuffs in Young Bulls.

This work studied the effect of feeding glycerin in bulls that were fed high levels of concentrate on the ruminal environment and in situ degradability of feedstuffs. Four ruminally cannulated young bulls were assigned to a 4 × 4 Latin square arrangement of treatments. The diets consisted of 15% barley straw and 85% concentrate in dry matter (DM). There were four different concentrates: without glycerin, and with 20, 40 or 80 g of glycerin per kg of DM. Each diet was offered for 24 days, the ruminal fluid was sampled to evaluate the ruminal metabolism and to determine the ruminal bacterial population by quantitative real-time polymerase chain reaction analysis, and the in situ degradability of six different feedstuffs was measured. The treatment with the highest level of glycerin provided the lower pH (p < 0.001), and the acetic/propionic molar ratio decreased (p < 0.001) as glycerin increased. The incorporation of glycerin in the diet did not affect the DNA copies/µL of the total bacteria, Butyrivibrio fibrisolvens and Butyrivibrio proteoclasticus (p > 0.05) in the DNA extract of rumen fluid, but at high levels increased Selenomonas ruminantium (p < 0.01). Very few effects of glycerin incorporation were found for the in situ degradability. In young bulls that were fed high levels of concentrate, glycerin at 20 or 40 g/kg of feed could be included without affecting the ruminal pH and raising the propionic acid, but at 80 g/kg the ruminal pH dropped, despite the increase of Selenomonas ruminantium.