The Effects of Bacillus licheniformis-Fermented Products on the Microbiota and Clinical Presentation of Cats with Chronic Diarrhea

Abstract

Bacillus licheniformis-fermented products (BLFP) are probiotics with antibacterial, antiviral, and anti-inflammatory properties that can improve growth performance. This study aimed to compare the fecal microbiota of diarrheal cats with chronic diarrhea (n = 8) with that of healthy cats (n = 4) from the same household using next-generation sequencing, and evaluate the effectiveness of oral administration of BLFP in relieving clinical signs and altering the intestinal microbiota in diarrheal cats. Six out of eight diarrheal cats showed clinical improvement after BLFP administration for 7 days, and the stool condition of the other two was normal. A higher Firmicutes/Bacteroidetes ratio was noted in the feces of diarrheal cats without clinical improvement as compared with those in the healthy cats and in the diarrheal cats with clinical improvement after receiving BLFP. The phylum Bacteroidetes and class Bacteroidia decreased significantly in diarrheal cats regardless of BLFP administration. Blautia spp., Ruminococcus torques, and Ruminococcus gnavus, which belong to the Clostridium cluster XIVa and have been reported as beneficial to intestinal health, increased significantly in feces after treatment. Furthermore, Clostridium perfringens also significantly decreased in diarrheal cats after BLFP administration. Overall, BLFP could be a potential probiotic to relieve gastrointestinal symptoms and improve fecal microbiota in cats with chronic diarrhea.

Keywords: Bacillus licheniformis-fermented products; chronic feline diarrhea; fecal microbiota; next-generation sequencing; probiotics.

Figure 1

Alpha diversity indices, including Chao1, Shannon, and Simpson. (A): All of the samples. (B): Alpha diversity of microbial communities before (red) and after (blue) the treatment of Bacillus licheniformis-fermented products (BLFP) in the diarrheal cats.

Figure 2

Beta diversity based on principal coordinate analysis (PCoA). (A): diarrheal cats (red dots) and control cats (blue dots). (B): diarrheal cats before (red dots) and after (blue dots) the treatment of Bacillus licheniformis-fermented products (BLFP).

Figure 3

(A) Relative distribution of the bacterial phyla of the fecal microbiome in the eight cats (No. 1–8) of the treatment group and the four cats (No. 9–12) of the control group before and after the treatment of Bacillus licheniformis-fermented products (BLFP). (B) Comparisons of the dominant phyla and class component between in the treatment (No. 1–8) group before and after the treatment with BLFP and in the control group (No. 9–12) without BLFP treatment. Black bar: before having BLFP in the treatment group or first sampling of feces in the control group. Grey bar: after having BLFP in the treatment group or second sampling of feces in the control group. * indicates p < 0.05.

Figure 4

(A) Relative distribution of the bacterial classes in fecal microbiome of eight cats (1–8) from the treatment group and four cats (9–12) from the control group before and after the Bacillus licheniformis-fermented products (BLFP) treatment. The list of the represented bacterial classes of other color bars is provided in Figure S1. (B) Bar chart of the selected bacterial class components in cats having diarrhea before (1–8C) and after (1–8T) BLFP treatment and in non-diarrheal cats without having BLFP (9–12C1 and C2). C: before the BLFP treatment; T: after the BLFP treatment; C1: first sampling of feces in the control group; C2: second sampling of feces in the control group.

Figure 5

Changes in the percentage of selected bacterial phylum and class components in diarrheal cats having clinical improvement (cats: 1, 2, 3, 6, 7, and 8) before and after Bacillus licheniformis-fermented products (BLFP) treatment and diarrheal cats (cats: 4 and 5) without clinical improvement. C: before the BLFP treatment; T: after the BLFP treatment.

Figure 6

The linear discriminant analysis (LDA) scores based on linear discriminant analysis effect size (LEfSe) results before (red) and after (green) Bacillus licheniformis-fermented products (BLFP) administration in diarrheal cats. C: before the BLFP treatment; T: after the BLFP treatment.