Cross-sectional study to identify the prevalence of and factors associated with laminitis in UK donkeys

Equine Vet J. 2021 Sep 3. doi: 10.1111/evj.13505. Online ahead of print.

Abstract

Background: Laminitis causes lameness in donkeys, but its prevalence and factors associated with disease remain uncertain.

Objectives: To determine the prevalence of and identify factors associated with laminitis in donkeys.

Study design: Retrospective cross-sectional study.

Methods: All donkeys at the Donkey Sanctuary, UK, October 2015 to March 2019 were included. For animals that had laminitis during this period, age, sex, weight, body condition score, and the onset date and type of each episode (first or recurrent, acute or chronic) were recorded. Additionally, management data, foot lesion score, endocrine data, other medical conditions, occurrence of foot trimming, surgical procedures, diagnostic imaging, behavioural modification therapy or movement between farms within the month prior were noted. Controls were animals that did not experience laminitis during this period and similar data were recorded. Multivariable logistic regression modelling assessed the differences between the control group and laminitis outcome groups (first, all laminitis, acute and chronic episodes).

Results: Altogether, 707 animals were included; 364 were control animals; 343 had a first episode of laminitis during the study period, of which 200/343 had no further episodes and 143/343 had recurrent episodes resulting in a total of 512 laminitis episodes and the period prevalence was 48.5% over 42 months. Overall, 180/512 (35%) laminitis episodes were acute and 332/512 (65%) were chronic. Compared with control animals, the laminitic outcome groups were significantly (P < .05) more likely to be younger (first episode), less likely to get extra feed (all four groups) or have an additional medical problem (first episode), and less likely to have undergone dental work, movement, imaging (all four groups) or surgery (first; all laminitis, chronic episodes) in the month preceding the episode.

Main limitations: These results may not be applicable to the wider donkey population.

Conclusions: Laminitis commonly affects donkeys, but factors associated with donkey laminitis differ from those reported in horses.

Keywords: PPID; donkey; endocrinopathy; horse; laminitis; risk factor.