Usefulness of Measuring Serum Amyloid A Concentration in Japanese Black Cattle in Clinical Practice.

This study investigated the concentration of serum amyloid A (SAA), an acute phase protein, in Japanese Black cattle. Four practical trials were performed to evaluate the transition of SAA and sialic acid before and after dehorning, the relationship between the SAA concentration and other blood test parameters, the SAA dynamics in the diseased cattle, and the blood test results, including the SAA concentrations, of the two cases with a follow-up. The SAA concentration increased with dehorning but decreased 7 days after dehorning. The SAA concentration is positively correlated with the α-globulin, sialic acid, and fibrinogen concentrations and negatively correlated with the serum iron concentration. The SAA concentration in the deceased herd was significantly higher than that in the cured outcome herd. In addition, the SAA concentration in the cured group decreased significantly from the first test to retesting but increased significantly in the disuse group. Thus, SAA is a sensitive index of inflammation and a monitoring tool in Japanese Black cattle, and its measurement is considered useful in clinical practice.

Serum Amyloid A Concentrations of Healthy and Clinically Diseased Japanese Black Breeding Cattle-Preliminary Measurements for Determining the Cut-Off Concentrations.

The present study aimed to compare serum amyloid A (SAA) concentrations of Japanese Black (JB) breeding cows in both clinically normal and diseased cows diagnosed by veterinarians using modified latex agglutination turbidimetric immunoassay (LATIA) to determine the cut-off values for healthy and diseased JB cows. For the comparison, a total of 289 serum samples of healthy cows without any clinical symptoms intended for the metabolic profile test and 66 serums from diseased cows clinically diagnosed by veterinarians were measured for the SAA concentrations. A significant difference (p-value = 6.68 × 10-29) was observed in the mean SAA concentrations between the healthy (2.8 ± 3.2 mg/L) and diseased (54.8 ± 76.8 mg/L) groups, and the median concentrations of the healthy and diseased groups were 1.5 mg/L and 31.2 mg/L, respectively. Finally, the cut-off SAA concentrations at each probability were 2.9 mg/L (p = 0.05), 5.7 mg/L (p = 0.1), 13.7 mg/L (p = 0.5), and 21.8 mg/L (p = 0.9), respectively, and 6.5 mg/L (p = 0.122) based on evaluation performed using the receiver operating characteristic curve. The results indicated that, with the practical application of the obtained cut-off value, the measurement of SAA concentrations for JB breeding cows with LATIA could be potentially beneficial in the early evaluation of inflammatory diseases in JB breeding cows and possibly useful in the prevention of not only metabolic diseases but also non-nutritional diseases during the perinatal period of JB breeding cows.