摘要：An easily performed test that can provide accurate, rapidly available results for quantitation of horse IgG has been developed using nephelometry. This test is expected to be used for diagnosis of such immunological diseases as failure of passive transfer of colostral immunoglobulin from mares, which is the most common immunodeficiency disorder in foals. Correlation coefficient and p value among results for single radial immunodiffusion test and the nephelometry in 58 half-bred horses were 0.850 and < 0.0005. The test was applied to quantitation of serum IgG from 100 race horses. The mean value was 1, 603 mg/dl, with a standard deviation of 294.8 mg/dl, a minimum value of 1, 004 mg/dl, and a maximum value of 2, 391 mg/dl. The test was also utilized to clinical practice in a farm. A relationship between IgG quantity at seven days after birth and the period from birth to the first day of therapy for clinical illness was observed for 16 foals of a farm until 180 days after birth. The IgG quantities at seven days after birth was 140 to 1, 700 mg/dl, and 12 foals were treated for common cold, bronchitis or pneumonitis within 135 days after birth. This result suggested that foals have the same possibility for clinical illness, regardless of their IgG quantities at seven days after birth. However, treated foals with lower IgG quantities tended to show clinical illness earlier after birth.
