Effects of live Bacillus pumilus or a Lacticaseibacillus paracasei postbiotic on apparent total tract nutrient digestibility and the fecal characteristics and metabolites, immunity, and microbiota of healthy adult dogs

Probiotics and postbiotics have the potential to shift the gut microbiota, support gastrointestinal health, and enhance immune function, but must be tested for safety and efficacy in the target species. The Bacillus and Lacticaseibacillus genera have been shown to positively influence microbial balance and enhance immune response in humans and livestock. The objective of this study was to determine the effects of live Bacillus pumilus SG-154 and a Lacticaseibacillus paracasei 327 postbiotic on dietary apparent total tract digestibility and the hematology, serum metabolites, fecal characteristics, metabolites, and microbiota, and skin and nasal microbiota of healthy adult dogs. Twelve healthy adult English pointer dogs (age = 6.38 ± 2.75 yr; body weight = 23.98 ± 4.61 kg) were used in a replicated 3x3 Latin square design to test the following treatments administered via gelatin capsules: 1) placebo (control; 250 mg maltodextrin/day); 2) live B. pumilus [5 x 109 colony-forming units (CFU)/day]; 3) L. paracasei postbiotic (derived from 2 x 109 CFU/day). Each experimental period was 28 days in length, including a 22-day adaptation phase, 5-day fecal collection phase, and 1 day for blood collection, nasal swabs, and skin swabs. Data were analyzed using the Mixed Model procedure of SAS, with P<0.05 being significant and P<0.10 being trends. Neither B. pumilus nor L. paracasei influenced nutrient digestibility, food intake, fecal output, or fecal characteristics. Based on 16S rRNA gene sequencing, the relative abundance of fecal Actinobacteriota tended to be higher (P<0.10) and the relative abundance of fecal Collinsella spp. was higher (P<0.05) in dogs given B. pumilus than those given L. paracasei and controls. Treatments appeared to shift skin bacteria as well, with the relative abundance of skin Erysipelotrichaceae UCG-003 being higher (P<0.05) in dogs given L. paracasei than dogs given B. pumilus. Skin Ligilactobacillus relative abundance was lower (P<0.05) in dogs given B. pumilus than controls. The relative abundance of skin Peptoclostridium was higher (P<0.05) in dogs given L. paracasei than controls. Most hematology measures were within the reference ranges for adult dogs and unaffected by treatment. Overall, our results demonstrate that consumption of the B. pumilus SG-154 and L. paracasei 327 tested are well-tolerated and do not influence nutrient digestibility or fecal characteristics in healthy adult dogs. Further studies testing their potential benefits on host health are required.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Animal Sciences

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Wren, Jocelyn Faith

Contributors dc:contributor

• Swanson, Kelly S
• Fahey, George C.
• de Godoy, Maria R. C.
• Loman, Brett R.

• Canine nutrition
• canine health
• probiotic
• postbiotic

Statement dc:rights

• Copyright 2025 Jocelyn Wren

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/129208

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F129208