Background: There is little scientific data about the effects of continuous supplementation with nutraceuticals over horse’s
health and performance. Horse owners and veterinarians are still using supplements for horses without any kind of evaluations.
At the Brazilian market is possible to buy hundreds of different products, but there is not private or state regulation over
production and quality of these products. The absence of information about quality and efficacy of these products may
contribute to mistakes in horse’s nutrition program. The objective of this research was to determine the effect of supplementation
with a combination of nutraceuticals over some blood parameters (red cell count, total plasma proteins, free plasma glutamine
and glutamate) and components of body composition in working horses.
Materials, Methods & Results: There were 19 gelding horses, divided in two groups: nutraceutical (NUTR; n=10) and placebo
(PLAC; n=9). Both groups received equivalent feeding regimens in regard to concentrate and grass, and did similar exercise
program. NUTR group received their pellets with nutraceuticals, and PLAC group received a placebo during the morning meal.
There is no visual difference between nutraceutical and placebo pellets. Body composition determination and blood collection
were taken in three periods: pre-test, after 4 and 12 weeks of supplementation. Body composition was determined after evaluation
of horse’s body mass by electronic scale associated with measurement of rump fat by ultrasound. Results showed that there were
no significant changes in body composition during 12 weeks of supplementation in both groups, which had percentage of body
fat around 13%. However, supplementation with nutraceutical produced significant changes (P <0.05) in some blood parameters
in NUTR group. This group had large red cell count, hematocrit and blood glutamine concentration when compared with PLAC
group after 12 weeks of supplementation. Blood glutamate concentration did not change in both groups.
Discussion: Supplementation with nutraceutical or placebo did not produce illness or other nutritional problem in the
experimental horses during 12 weeks. Also, because the nutraceutical and placebo pellets were visually similar to horse’s grain,
the experimental animals did not have problems to eat all feed during 12 weeks. During this period it was observed that NUTR
group had some improvement of the blood parameters when compared with PLAC group (P <0.05), without adaptation or
changes in body mass. Frequently supplement’s advertises use improvement in the body mass as major effects of their
products, but some of these effects are subjective because they use body score to show supplementation’s results. Increase in
hematocrit (>16%), total plasma protein (>7%) and free plasma glutamine (>20%) observed in NUTR group will contribute to
horse’s performance since it is positive action on red blood indexes and plasma amino acid concentration, contributing to the
well-being of this horse group. Increase in blood glutamine concentration observed in NUTR group without improvement of
body composition was not expected because this amino acid is produced mainly by skeletal muscle. Increase in fat-free mass
frequently is associated with improvement of blood glutamine concentration. Finally, initial elevation in few parameters in
PLAC group at 4 weeks of supplementation probably was associated with improvement of general management practices. In
conclusion, supplementation with a nutraceutical combination, for 12 weeks, produces changes in the concentration of some
blood parameters, but it didn’t modify the corporal composition. The elevation of those components can favor the transport of
oxygen and nutrients in tissues leading to improvement in the horse performance.
