Stability of total proteins and their electrophoretic fractions in goat serum (Capra hircus), maintained under different condition

- We assessed the influence of storage conditions on serum total protein of goat.
- We assessed storage influence on serum electrophoretic protein fractions of goat.
- Significant effect of storage conditions on serum total protein was found.
- Significant effect of storage conditions on serum protein fractions was found.
- Fresh caprine serum samples are suggested for protein electrophoretic analysis.

The aim of the present study was to evaluate the effect of different storage time and temperature conditions on the concentration of serum total proteins and their electrophoretic fractions in goats. Blood samples were collected from 12 female of Girgentana goats and the obtained serum was divided into 4 aliquots. The first aliquot was analyzed immediately after separation (T0); the second was refrigerated at 4 °C and analyzed after 24 (T1), 48 (T2), and 72 (T3) hours; the third was stored at −20 °C immediately after centrifugation and analyzed after 2 days (T4); and the last aliquot was stored at −20 °C after 24 h refrigeration and analyzed after 1 week (T5). The serum total proteins, serum protein electrophoretic fractions (albumin, α-, β1-, β2- and γ-globulins) and albumin/globulin ratio (A/G) values were determined. A significant effect of storage conditions on serum total proteins, albumin, α1-, β2- and γ-globulins values was found (P < 0.05). The concentration of serum total proteins was significantly higher at T1 and T4 than T0. Albumin showed higher concentrations at T1, T2, T3, T4 and T5 in respect to the values measured at T0. The concentration of α1-globulins was significantly higher at T4 than T0; the β2-globulins values were lower at T3 and T5 respect to T0, whereas the γ-globulins values were lower at T5 than T0. Together these results showed that temperature and time of serum storage are important pre-analytical factors which affect concentrations of serum total proteins and their electrophoretic fractions in electrophoretic analysis. The results of present study suggest that fresh serum samples or samples refrigerated for 24 h are recommended for electrophoretic analysis to obtain accurate data, which can help clinicians to differentiate between sick and healthy animals.