Effects of a multi-strain probiotic on growth performance and faecal microflora in weaner pigs

Weaning stress leads to pigs being susceptible to gastrointestinal disorders and digestive disturbances, thus resulting in a high incidence of diarrhoea and depressed growth rate (Lallès et al. 2007). It has been suggested that probiotics could promote intestinal health and alleviate weaning stress in young pigs (Lan et al. 2016). Therefore, the objective of the present study was to evaluate the effect of a multi-strain probiotic (Bacillus subtilis 1.0 × 10⁹ cfu/g and Bacillus lichenformis 1.0 × 10⁹ cfu/g) on growth performance and faecal microflora in weaner pigs.

A total of 120 weaner pigs ((Landrace × Yorkshire) × Duroc) with an average bodyweight (BW) of 7.84 ± 1.75 kg (28 days of age) were randomly allocated to four experimental diets: (1) CON, basal diet; (2) CON + 0.1% multi-strain probiotics; (3) CON + 0.2% multi-strain probiotics; and (4) CON + 0.3% multi-strain probiotics. All data were statistically analysed using the GLM procedure of the SAS v9 (SAS Institute Inc., Cary, NC, USA). Orthogonal comparisons were conducted using polynomial regression to determine linear, quadratic and cubic effects. Feed consumption was recorded on a pen basis during the experiment, and individual pig BW was recorded at initial, d 7, 14 and 42 of the experimental period to calculate average daily gain (ADG), average daily feed intake (ADFI), and gain : feed (G : F). Lactobacillus, E. coli were determined by serial dilution (10⁻¹ to 10⁻⁷) on selective media. The results are shown in Table 1.

Table 1.  Effect of probiotics on growth and faecal microflora in weaner pigs

In this study, during d 1 to 7, dietary supplementation of three concentrations of a multi-strain probiotic increased (linear effect, P < 0.05) the G : F. During d 14 to 42 and d 1 to 42, increasing the level of the dietary multi-strain probiotic improved (linear effect, P < 0.05) the ADG and G : F. At the end of experiment, dietary supplementation with the multi-strain probiotic decreased (linear effect, P < 0.05) the faecal E. coli counts.

In conclusion, dietary supplementation of a multi-strain probiotic (B. subtilis and B. licheniformis) exerted a positive influence on growth rate and faecal microflora in weaner pigs.