Caracterización de IgM, IgG Total, IgG1 y anticuerpos de cadena pesada en calostro de llamas ("Lama glama") mediante Elisa

Objectives : to determine the levels of IgM, total IgG, IgG1 and HCAbs (IgG2 and IgG3) in colostra of llamas and to evaluate the concentration of HCAbs in relation to total IgG and the conventional isotype IgG1. Methods : Fifteen pregnant llamas were used in this study, which were milked within the first 24 hours after delivery. Sandwich ELISAs were designed for the quantification of IgM, total IgG and IgG1. The HCAbs concentration was calculated by difference between total IgG and IgG1 (HCAbs = total IgG – IgG1). Results : The levels of Igs were found to be: IgM= 17.02 mg/ml (SD= 9.85), total IgG= 42.54mg/ml (SD=27.79), IgG1=24.34mg/ml (SD=13.96) and HCAbs (IgGtotal-IgG1) = 18.19 mg/ml (SD=15.49). Results regarding total IgG are consistent with those described in other species with similar type of placentation. HCAbs represented 43% of colostral IgG and IgM concentration presented values that were much higher (two and three times respectively) than those described for species with similar type of placentation. Conclusions : This study is the first which evaluate amounts of each immunoglobulin isotype in colostra of llamas. We described a higher value of IgM in in comparison with species with similar placentation type. The IgG1 isotype, which represents the conventional isotype, is the more abundant antibody in colostra, being the HCAbs the second important fraction. This information may be useful in the management of neonates with failures in the transference of maternal passive immunity by colostra.