OBESITY, UREA, URIC ACID: DONKEYING AROUND WITH SUBCLINICAL METABOLIC
IMBALANCES (PILOT STUDY)
Abstract
Background – Obesity is a key precipitating factor in
laminitis development and frequent problem in many donkey farms across
Europe. Stoic nature of donkeys makes laminitic changes often going
unnoticed or mistakenly attributed to hoof neglect. Objectives
– To investigate link between obesity, metabolic profile, inflammation,
and laminitis, focusing on physical examination and serum biomarkers.
Study design – Cross-sectional observational study.
Methods – Ten randomly chosen lactating jennies over four
years of age, from one farm, being fed with hay and bran, were enrolled
in the study. Body condition score (BCS) was assessed using Pearson’s
system. Grading scales for fat accumulations and laminitic hoof
deformities were developed. Welfare was assessed using AWIN protocol.
Blood samples for biochemistry analysis were collected after fasting.
Data were presented as median [minimum, maximum] and analysed with
MedCalc® software, with p<0.05 considered significant.
Results – Laminitic hoof deformities (0.5 [0, 1]), were in
strong positive correlation with BCS (7 [4, 8], p=0.008) and
fat accumulations (1.5 [0, 2.5], p=0.017). The category of
jennies with BCS≥7 had higher insulin than group with BCS<7 (
p=0.044). Insulin (34.86 pmol/L [8.33, 75]) showed positive
correlation with glucose (4.12 mmol/L [3.8, 5.4],
p<0.001), cholesterol (1.92 mmol/L [1.53, 2.38],
p=0.008), and AST (461.6 U/L [379.1, 1037.6],
p=0.023). Uric acid (0.20 mmol/L [0.09, 0.62]) showed
positive correlation with BCS ( p=0.033) and urea (6.46 mmol/L
[3.84, 8.68], p=0.048). Urea levels exceeded reference range
in eight, and globulins in all the jennies. Main limitations –
Small sample size, unknown gestational state, unawareness of individual
food intake. Conclusions – In lactating, normoinsulinaemic and
normoglycaemic jennies, over-conditioning is linked to subclinical
laminitis. However, clear metabolic link is missing. Increased globulins
suggest subclinical chronic inflammation, while the increase in urea and
variable levels of UA suggest the need for thorough assessment of proper
feeding management.