Serum protein concentration and protein fractions in clinically healthy Lacaune and Sarda sheep using agarose gel electrophoresis

Background: Serum protein electrophoresis (SPE) provides useful information in ruminants, but reference intervals (RI) are different from other species. There have been no reports of SPE RI for dairy sheep using agarose gel electrophoresis (AGE). Objective: The purpose of the study was to evaluate the serum concentration of total protein (TP) and protein fractions determined by AGE in mid-lactating dairy ewes, to establish RI, and to assess potential differences between Lacaune (L) and Sarda (S) sheep breeds. Methods: Blood samples were collected from healthy, mid-lactating ewes. SPE was assessed using a semi-automated AGE system. Reference intervals (90% confidence intervals) for TP and each protein fraction were determined using the nonparametric method for combined data, and the robust method for data from the single breeds. Data from S and L sheep were compared using the Mann-Whitney U test. Results: The 172 sheep included 116 L and 56 S ewes, 2-6 years old. There were significant differences between S and L breeds, and RI were calculated for TP, albumin, α1-globulin, α2-globulin, β1-globulin, β2-globulin, γ1-globulin, and γ2-globulin concentrations, and for the Albumin/Globulin ratio. Group S showed higher concentrations of TP, α2-, β1-, β2-, and γ1-globulins, whereas L was higher for albumin and γ2-globulin concentrations, and A/G ratio (P < .05). Conclusions: The resolution with AGE was excellent, allowing standardization of 7 protein fractions, detection of differences between S and L ewes, and determination of RI for French (Lacaune) and Italian (Sarda) dairy sheep. © 2015 American Society for Veterinary Clinical Pathology.