Pattern of serum protein fractions in goats and ewes during different physiological stages

A deep knowledge on the specific changes taking place during pregnancy and lactation is necessary in clinical practice since, at this time, all metabolic functions vary to satisfy the demands of the foetus/newborn. Therefore, the aim of this study was to analyze the modifications of serum total proteins, albumin, α-globulins, β1-globulins, β2-globulins and γ-globulins during different physiological stages in healthy goats and ewes. Five Girgentana goats (3 years old, mean body weight 41.0±5.0 kg) and five Comisana ewes (3 years old, mean body weight 46.1±3.2 kg) were used. Blood samples were collected from each animal at week 18 of pregnancy (late pregnancy, LP), within 2 day post-partum (PP), and at week 5 (early lactation, EL) and 20 (advanced lactation, AL) post-partum. All samples were analyzed for serum proteins profile with routine methods. Two-way ANOVA showed a significant effect of different reproductive stages on all serum parameters considered in booth species. No species-related effect was detected in all studied parameters. In particular, total proteins, β1-, β2- and γ-globulins showed highest values during LP and PP. Starting from PP, α-globulins increased reaching a peak in AL. EL is characterized by low γ-globulins values. A significative increase in albumin/globulin ratio (A/G) was found during EL and AL, which is due to higher serum albumin concentration and to the drop in some globulin fractions. Our results contribute to better understand how serum protein profile change during different reproductive stages and provide useful tools for the evaluation of the management practice, nutrition and diagnosis of small ruminant.