title: Blood and colostrum/milk serum gamma-glutamyltransferase activity as a predictor of passive transfer status in lambs.
abstract: The importance of blood and colostrum/milk serum gamma-glutamyl transferase (gamma-GT) enzyme activity was evaluated to assess passive transfer status in healthy lambs. Thirty Akkaraman sheep (3-6 years old) were used which had normal pregnancy period and the same conditions, and the age of the lambs ranged between 0 and 15 days. Blood and colostrum/milk samples were collected from sheep and lambs after birth, before suckling (0) and after on 1st, 3rd, 7th and 15th days. Serum immunoglobulin G (IgG) concentration was determined by the use of Single Radial Immunodiffusion method. Serum gamma-GT activity was measured, using a commercially available kit in blood and colostrum/milk samples. Correlations were carried out between immunoglobulin and gamma-GT levels. Regression models (simple and multiple) were calculated with significant data. Linear correlation was determined between colostrum/milk gamma-GT activity and IgG concentrations and between serum gamma-GT activity and IgG concentrations in lambs on the 0 day. (r: 0.607, P: 0.001), 1st (r: 0.768, P: 0.001) and the 3rd (r: 0.603, P: 0.001) days and on the 1st (r: 0.637, P: 0.001) and 3rd (r: 0.478, P: 0.012) days in the experiment, respectively. Multivariate regression models were developed to estimate sample IgG concentration. Serum and colostrum/milk IgG concentration could be predicted using the formula: lamb serum IgG = 825 + 0.688 (lamb gamma-GT) + 52 (days); colostrum/milk IgG = 832 + 0.505 (colostrum/milk gamma-GT) - 167 (days). The regression models were moderately accurate in predicting serum IgG concentration (R2 = 0.51) and colostrum/milk IgG concentration (R2 = 0.55). Test sensitivity and positive predictive values for serum gamma-GT enzyme activity were found to be 96 and 100% and for colostrum/milk gamma-GT enzyme activity were found to be 100 and 68% to prediction IgG concentration. Serum and colostrum/milk gamma-GT activity can be used to assess passive transfer status of lambs. Along with this, regression models used to calculate serum and colostrum/milk gamma-GT activities found to be useful to estimate sample IgG concentration. The use of serum and colostrum/milk gamma-GT enzyme activity was found useful especially after birth on the 0, 1st and 3rd days.
authors.affiliation: Department of Veterinary Internal Medicine, Faculty of Veterinary Medicine, Selcuk University, 42031, Campus, Konya, Turkey. mmaden@selcuk.edu.tr
authors.forename: M
authors.initials: M
authors.lastname: Maden
authors.forename: V
authors.initials: V
authors.lastname: Altunok
authors.forename: F M
authors.initials: FM
authors.lastname: Birdane
authors.forename: V
authors.initials: V
authors.lastname: Aslan
authors.forename: M
authors.initials: M
authors.lastname: Nizamlioglu
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000097:blood / Q000276:immunology; D000833:Animals, Suckling / Q000097:blood / Q000276:immunology; D003126:Colostrum / Q000201:enzymology / Q000276:immunology*; D005260:Female; D007112:Immunity, Maternally-Acquired; D007074:Immunoglobulin G / Q000097:blood*; D011237:Predictive Value of Tests; D011247:Pregnancy; D012044:Regression Analysis; D012680:Sensitivity and Specificity; D012756:Sheep / Q000097:blood / Q000276:immunology*; D005723:gamma-Glutamyltransferase / Q000097:blood / Q000378:metabolism*
chemical_list: D007074:Immunoglobulin G; D005723:gamma-Glutamyltransferase