title: Prediction of serum IgG1 concentration in beef calves based on age and serum gamma-glutamyl-transferase activity.
abstract: This study examined the relationship between serum gamma-glutamyl-transferase (GGT) activity and passive transfer status in beef calves less than 18 days of age. Immunoglobulin G1 (IgG1) concentrations were measured in 69 commercial beef calves between the ages of 24 and 72 hours. GGT activities were then measured in these same calves at various ages between 3 and 18 days of age. Models were developed predicting serum IgG1 concentration as a function of calf age and serum GGT activity. Minimal association was present between initial serum IgG1 concentration and serum GGT activity when all calves less than 18 days of age were considered (r2 = 0.065). When the study population was restricted to calves less than 8 days of age, the fit of the developed model was greatly improved (r2 = 0.438). Serum GGT activity has no apparent advantage relative to other assay procedures for predicting passive transfer status in beef calves. If serum GGT activity is to be used to assess passive transfer status in beef calves, application of this procedure should be restricted to calves less than 8 days of age.
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, USA.
authors.forename: L K
authors.initials: LK
authors.lastname: Wilson
authors.forename: J W
authors.initials: JW
authors.lastname: Tyler
authors.forename: T E
authors.initials: TE
authors.lastname: Besser
authors.forename: S M
authors.initials: SM
authors.lastname: Parish
authors.forename: R
authors.initials: R
authors.lastname: Gant
mesh_terms: D000375:Aging / Q000097:blood / Q000276:immunology*; D000818:Animals; D000831:Animals, Newborn / Q000097:blood / Q000276:immunology; D002417:Cattle / Q000097:blood / Q000276:immunology*; D007116:Immunization, Passive / Q000662:veterinary*; D007074:Immunoglobulin G / Q000097:blood*; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012016:Reference Values; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D007074:Immunoglobulin G; D005723:gamma-Glutamyltransferase