effect of monensin sodium on metabolic profile of ewes before and pospartum

The study was carried out to analyze the effect of monensin supplementation during 60 days prior to parturition, and 30 days postpartum, on the metabolic and hormonal profile of ewes. Pregnant ewes (n=13) were randomly divided into two groups: monensin group (n = 7; 30 mg/day) and control group (n = 6). Blood and ruminal fluid samples were collected 60, 50, 40, 30, 20 and 10 days prior to parturition, at the time of parturition and on 10, 20 and 30 days postpartum. The following variables were analyzed: glucose, fructosamine, non-esterfied fatty acids, ?-hydroxybutyrate, cholesterol, triglycerides, total protein, albumin, urea and ketone bodies in the urine. The hormonal determinations were cortisol and insulin. The analysis of the ruminal fluid involved pH and concentration of volatile fatty acids. The statistical analysis involved ANOVA and correlation studies (P<0,05). Monensin increased (P<0,05) the propionic acid concentration in the rumen and blood fructosamine and insulin. The administration of monensin improved some indicators of energy balance. Keywords: ionophor; profile energy; profile protein; sheep; volatile fatty acids.