Effects of Se supplementation on growth rate and blood parameters in lambs

摘要

Abstract Forty-eight Appenninica lambs 30 d old received during a 63 d period the same diet (dry unifeed) supplied 4 different mineral premixes differing for their Se sources and levels to obtain the following 4 treatments (on an as fed basis): Control group (T1) - 0mg/kg Se; T2 – 0.30mg/kg Se as sodium selenite; T3 – 0.30mg/kg and T4 – 0.45mg/kg Se as Se yeast ( Saccharomyces cerevisiae). Biweekly all the animals were weighed and feed consumption recorded. Moreover, at start (t₀) and successively each two weeks (t₁₄, t₂₈, t₄₂, t₅₆), all the animals were blood sampled in order to evaluate plasma and whole blood Se concentration and blood glutathione peroxidase (GSH-Px) and creatine phosphokinase (CPK) activities. Daily weight gain (averaging 166±6g/d) never differed between treatments. Se supplementation increased Se concentration in blood in relation to dietary level (p<0.05) and, compared to selenite, Se yeast seemed more effective to obtain higher concentration in whole blood (P<0.05) but not in plasma. Blood GSH-Px activity was higher in lambs receiving Se supplementation but was not influenced by Se dietary level or source. No effects could be find on blood CPK activity.