TY - JOUR N2 - A recent study found that an agarose gel electrophoresis (AGE) method yielded two distinct major bands corresponding to the hepatic and bone ALP isoenzymes (ALP2 and ALP3, respectively) in bovine serum treated with protease and neuraminidase (PN-treatment), although there were concerns that the intestinal ALP isoenzyme (ALP5) often overlapped with ALP3 in human serum treated with neuraminidase. Because ALP5 was separated from ALP3 in bovine serum treated with protease alone (P-treatment), we used a modified method employing both P- and PN-treated bovine sera to measure the activities of the three ALP isoenzymes in 53 lactating Holstein cows: 24 primiparous and 29 multiparous. Upon electrophoresis, 51 of 53 samples (96.2%) subjected to P-treatment yielded a distinct fraction corresponding to ALP5, as did the control serum. All PN-treated sera yielded a definite ALP2 fraction. The ALP3 fraction was calculated as the remainder after excluding ALP2 and ALP5. The activities of total ALP (t-ALP) and ALP3 in primiparous cows were higher than those in multiparous cows (p < 0.001) at early-to-peak [10–110 days in milk (DIM)] and mid (111–220 DIM) lactation. In the multiparous cows, the ALP3 activity at late lactation (221−477 DIM) was significantly higher than that at early-to-peak lactation. Thus, the modified AGE method described here is able to discriminate three fractions of ALP isoenzymes in the sera of lactating cows. The AGE pattern of circulating ALP isoenzymes will contribute to the understanding of the physiological bone metabolism status in lactating cows. L1 - http://www.czasopisma.pan.pl/Content/116778/PDF/20.pdf L2 - http://www.czasopisma.pan.pl/Content/116778 PY - 2020 IS - No 2 EP - 319 DO - 10.24425/pjvs.2020.133648 KW - agarose gel electrophoresis (AGE) KW - alkaline phosphatase isoenzyme KW - lactating cow A1 - Chiba, A. A1 - Hatate, K. A1 - Onomi, R. A1 - Moriyama, T. A1 - Goto, A. A1 - Yamagishi, N. PB - Polish Academy of Sciences Committee of Veterinary Sciences PB - University of Warmia and Mazury in Olsztyn VL - vol. 23 DA - 2020.06.29 T1 - Agarose gel electrophoresis pattern of serum alkaline phosphatase isoenzymes in Holstein cows during lactation SP - 317 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/116778 T2 - Polish Journal of Veterinary Sciences ER -