Evaluation of a rapid specific test for detecting colostral IgG1 in the neonatal calf

A commercially available latex agglutination test was used to measure the concentration of IgG1 in bovine plasma and the results were compared with radial immunodiffusion and zinc sulphate turbidity methods. For concentrations of IgG1 up to 80 g/litre there were highly significant (P less than 0.001) correlation coefficients between the latex agglutination test and radial immunodiffusion, and between the latex agglutination test and zinc sulphate turbidity method (0.93 and 0.74 respectively). The coefficient of variation for the latex agglutination test ranged from 8.1 per cent to 17.9 per cent. IgG1 concentration was measured using the latex agglutination test in whole blood on a farm, in whole blood at a laboratory and in plasma at a laboratory. The correlation coefficients were highly significant (P less than 0.001) in all cases. The latex agglutination test is easy to use, rapid and specific. It is suitable for checking the colostral status of young calves on commercial farms.