PhD in Veterinary Sciences for Animal Health and Food Safety

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Curriculum vitae

Phd thesis

PhD Thesis Title

Improving Gastrointestinal Health and Wellbeing in Dogs under Breeding Conditions: Efficacy of a Natural Dietary Supplement

Summary

This three-year PhD project focused on the development and evaluation of a novel natural dietary supplement composed of bromelain, quercetin, and Lentinula edodes (shiitake mushroom) to improve gastrointestinal (GI) health and overall wellbeing in dogs kept under stressful breeding (kennel) conditions. The supplement was tested through a combination of in vitro and in vivo studies, assessing its antioxidant potential, effects on inflammatory markers, and influence on gut microbiota composition.

Study 1

Aim: Select suitable natural compounds and assess their antioxidant properties individually and in combination.
Outcome: Identified a synergistic combination with strong antioxidant activity, effective in reducing oxidative stress-related GI inflammation.

Study 2

Aim: Formulate the supplement and evaluate its effects on GI health in vivo.
Outcome: Supplementation improved intestinal barrier function and reduced biomarkers of stress and inflammation in American Staffordshire Terrier dogs.

Study 3

Aim: Analyze the impact of the supplement on gut microbiota composition and diversity.
Outcome: Observed a significant increase in beneficial bacteria (e.g., Lactobacillus, Bifidobacterium, Pediococcus) and a reduction in taxa linked to harmful fermentation, supporting improved GI health.

Conclusion

The study demonstrates the potential of natural antioxidant-based dietary supplements as a safe and effective alternative for managing gastrointestinal health in dogs, especially in high-stress kennel environments. The supplement improved gut health markers, modulated the microbiota favorably, and maintained body condition, offering promising applications for canine wellbeing.

Research activities

Study 1:  Initial Investigations and In Vitro Antioxidant Chemical Analyses

1. Objective: To evaluate the antioxidant properties of bromelain, quercetin, and Lentinula edodes (shiitake mushroom).
2. Activities:
   • I conducted extensive literature review to select natural ingredients with potential antioxidant properties.
   • I performed in vitro assays to measure Total Phenolic Content (TPC), DPPH Free Radical Scavenging Activity, and ABTS Radical Cation Decolorization.
   • I formulated a dietary supplement based on the results of the individual and combined antioxidant capacities of the selected ingredients.

Study 2:  In Vivo Trials and Initial Analysis

1. Objective: To assess the safety and efficacy of the formulated dietary supplement on GI health in dogs under breeding conditions.
2. Activities:
   • I conducted a double-blind, placebo-controlled trial involving 30 dogs, divided into treated and control groups.
   • I collected fecal samples at weekly intervals over a 35-day period.
   • I measured fecal markers including calprotectin, histamine, indole/skatole, pH, and Short-Chain Fatty Acids (SCFA).

Study 3:  Microbiota Analysis and Advanced Insights

1. Objective: To investigate the impact of the dietary supplement on the gut microbiome and its broader implications.
2. Activities:
   • I extracted and quantified microbial DNA from fecal samples.
   • I conducted 16S rRNA sequencing and bioinformatics analysis using QIIME 2 and R software.
   • I analyzed microbial community richness and evenness (Alpha diversity) and community composition (Beta diversity).
   • I identified specific taxa significantly affected by the supplement.

Publications