Dietary supplementation with postbiotics from Bifidobacterium animalis in adult beagle dogs: effects on immunity, oxidative stress, bone metabolism, and coat quality
Bifidobacterium animalis postbiotics (0.05% and 0.1%) favorably shifted immune, antioxidant, and coat quality markers in adult beagle dogs without altering growth performance or routine hematological parameters.
| Outcome | Grade | Direction | Effect | Studies |
|---|---|---|---|---|
| Serum immunoglobulins (IgA, IgM, IgG) | C | ▲ Favorable | aumento significativo IgA (LDP+HDP), IgM+IgG (HDP); IC 95% NR | 1 |
| Pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) | C | ▲ Favorable | reducao TNF-α+IL-6 (LDP+HDP), IL-1β (HDP); IC 95% NR | 1 |
| Oxidative stress markers (MDA, SOD, GSH-Px, CAT) | C | ▲ Favorable | MDA menor HDP; SOD aumentou LDP+HDP; GSH-Px+CAT aumentaram HDP; IC 95% NR | 1 |
| Bone formation markers (PINP, OC) | C | ▲ Favorable | aumento PINP+OC em HDP; IC 95% NR | 1 |
| Coat quality (cuticle, amino acids) | C | ▲ Favorable | melhora cutícula+aminoácidos (LDP+HDP); IC 95% NR | 1 |
| Growth performance and routine hematological parameters | C | — Neutral | sem diferença entre grupos; IC 95% NR | 1 |
| Gut microbiota and fecal short-chain fatty acids | C | ▲ Favorable | aumento Limosilactobacillus/Lactobacillus; reducao Peptoclostridium/Streptococcus; aumento acidos acetico+propionico+isovalerico (LDP+HDP); IC 95% NR | 1 |
Context
Postbiotics — preparations of inactivated microorganisms or their components — offer greater stability and safety than live probiotics. Evidence on their effects in companion dogs is scarce. Controlled studies in canine models are needed before clinical extrapolation.
What the study showed
Postbiotic supplementation increased serum IgA in both dose groups (LDP and HDP); IgM and IgG increased only in HDP. TNF-α and IL-6 decreased in both groups; IL-1β decreased only in HDP; IL-10 increased only in LDP. MDA was lower in HDP; SOD increased in both groups; GSH-Px and CAT increased significantly only in HDP. Bone markers PINP and OC increased in HDP. Coat quality improved (smoother cuticle, higher glutamic acid, cysteine, proline) in both groups. No differences were observed in growth or routine blood counts. Absolute values, effect sizes, and 95% CIs were not reported in the available extract, preventing precise quantification.
How it was done
Controlled trial in adult beagle dogs with three groups (CONT, LDP, HDP) over 42 days. Exact animal numbers per group and detailed demographic characteristics were not provided in the available extract. Assessments included immune serology, oxidative markers, bone biochemistry, coat amino acid analysis, fecal short-chain fatty acids, and gut microbiota sequencing.
Effect magnitude
Effect sizes (RR, MD, SMD) and 95% CIs were not reported in the available text; magnitude of effects cannot be quantified from the data provided.
Limitations
Sample size was not stated in the available extract and is likely small (typical for laboratory beagle studies), reducing statistical power and generalizability. Absence of 95% CIs and effect sizes prevents GRADE assessment. A 42-day duration is insufficient for long-term outcomes (bone health, adaptive immunity). The study used healthy animals, limiting applicability to dogs with established diseases. No risk-of-bias tool (e.g., RoB 2, SYRCLE) was mentioned or applied.
In clinical practice
This single study does not support clinical recommendation of B. animalis postbiotics for dogs in clinical settings. Clinicians should await replication with larger samples and clinically relevant outcomes (morbidity, infection recurrence, disease remission). The absence of adverse effects over 42 days provides preliminary safety data only.
What is still missing
Trials with adequate sample sizes, longer durations, and dogs with established conditions (dermatitis, osteoarthritis, immunodeficiency) are required to establish clinical efficacy. Mechanistic pathways via microbiota modulation require validation with dedicated mechanistic designs.