Investigations on the degradation of starch in the equine stomach using proteome and microbiome analyses, as well as functional and structural analysis of important digestive enzymes

• Applicant: Professorin Dr. Annette Zeyner, since 1/2024
• Subject Area: Animal Breeding, Animal Nutrition, Animal Husbandry
• Term: from 2020 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 434510792

Knowledge on the effects of high-starch diets on the gastrointestinal and metabolic health of horses is essential regarding the common use of concentrates in equine practice. Previous studies have shown that a significant amount of starch is already fermented by microbes in the stomach followed by enzymatic digestion in the small intestine and, as the case may be, also in the large intestine. Detailed investigations on gastric starch degradation in vivo are limited due to the necessity of invasive (nasogastric tubes) or post mortem sampling methods. The objective of the purposed project is to characterise the endemic microbiome and proteome of the equine stomach, with a main focus on bacteria and yeasts that are associated with either the chymus or the mucosa, and to identify plant and microbial enzymes that are playing a major role for the degradation of starch in the stomach. Information on type and origin of abundant enzymes in the stomach of horses, as well as on the interrelationship among them and their pH dependency, will enable a much better assessment of high-starch concentrates, and suitable recommendations for the feeding practice. Details on the stomach's environment, and its dependency from different feeding regimens, can be aquired with this project.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Martin Bachmann, until 12/2023