Effect of Calsporin® (Bacillus subtilis C-3102) addition to the diet on faecal quality and nutrient digestibility in healthy adult dogs

This study evaluated the effect of Bacillus subtilis C-3102 (Calsporin ® ) addition to the diet on faecal characteristics and nutrient digestibility in healthy adult dogs. Sixteen Beagles received either a low-energy control diet (CON; 3.35 Mcal metabolisable energy (ME)/kg with 21.8, 27.9, and 50.3% ME as protein, fat, and nitrogen-free extractives (NFE), respectively) or the same diet supplemented with Bacillus subtilis at 1 × 10 9 CFU/kg diet as probiotic (PRO) for four weeks in a parallel design (eight dogs per diet). In the prior two weeks, all dogs received a high-energy diet (Advance Medium Adult, Affinity Petcare ® , 3.81 Mcal ME/kg ME with 24.8, 41.2, and 34% ME protein, fat, and NFE, respectively). Faecal consistency, dry matter (DM), pH, and NH 3 were analysed on fresh samples collected at the start and weekly throughout the study. Additional samples were collected for the determination of lactate and short-chain fatty acids (SCFA) on days 0 and 21. In week four, a five–day total faecal collection was conducted in six dogs from each diet for the determination of nutrient apparent digestibility. Dogs fed the PRO diet had more firm faeces (P = 0.011) than control dogs and a higher faecal DM content in the first two weeks (P 3 over four weeks (P = 0.05) and in faecal pH in the first two weeks (P 0.10). Dogs fed the PRO diet showed a higher apparent digestibility of fat (P = 0.031) and NFE (P = 0.038) compared to control dogs. Dog food supplementation with Calsporin ® at 1 × 10 9 CFU/kg improved faecal quality, enhanced fat and carbohydrate digestibility, and contributed to the gut health of dogs by reducing gut ammonia and increasing SCFA content.