Effect of premolar and molar occlusal angle on feed digestibility, water balance, and fecal particle size in horses.

Objective: To determine whether occlusal angle of the premolar and molar teeth (ie, molar occlusal angle) was associated with feed digestibility, water balance, or fecal particle size in adult horses.

Design: Observational study.

Animals: 40 pregnant mares ranging from 3 to 19 years old.

Procedure: The horses were randomly allocated to 1 of 5 feeding groups with 8 horses/group. Horses were sedated, and molar occlusal angle was measured with 2 methods. An oral examination was performed, and total number of dental abnormalities was recorded. Feed digestibility, water balance, and fecal particle size were measured 7 and 16 weeks later.

Results: Molar occlusal angle ranged from 6.3 degrees to 19.3 degrees and was not significantly associated with feed digestibility, water balance, or fecal particle size. The number of dental abnormalities was not associated with feed digestibility. Molar occlusal angle did not vary significantly with horse age.

Conclusions And Clinical Relevance: Results indicate that molar occlusal angles between 6 degrees and 19 degrees do not adversely affect feed digestibility, water balance, or fecal particle size in adult horses. Additionally, there was no association between age and molar occlusal angle.