Plasma insulin concentration is affected by body condition in Icelandic horses
© Jansson et al. 2015
Published: 25 September 2015
Little is known about the variation in plasma insulin levels in Icelandic horses and factors that influence it.
The aim was to describe the variation in plasma insulin levels in a group of healthy Icelandic horses showed at a breed evaluation field test (evaluation of gaits under rider and conformation) and to document possible relationships between insulin levels and sex, age, body weight, height, body condition score (BCS) and management such as subjective level of fitness, travel time and daily forage and concentrate allowance.
Data from 201 horses were collected (4-11 years). Body condition score was assessed using a 5-degree scale. A venous blood sample was taken before the gait test. Plasma insulin were analysed in duplicates by ELISA and between samples variation was <10%. ANOVA (mixed model) was used (effects considered significant at p<0.05).
Plasma insulin levels ranged from 0.01 to 0.60 µg/L. Concentrate allowance and BCS had a significant effect on the plasma insulin level. BCS ranged from 2.3 to 4.0 (approximately 4 to 7 on a 9-degree scale) and concentrate allowance from 0 to 4 kg. For one degree of increase in BCS, log-insulin increased with 0.45 µg/L and for every kilo of increase in the concentrate allowance, log-insulin increased with 0.26 µg/L.
In Icelandic horses considered to be fit for a breed evaluation field test, plasma insulin levels increased not only due to increased concentrate intake as could be expected, but also to a considerable extent due to an increase in BCS.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.