Sato Kaoru, Ohashi Eiichi, Tsukano Kenji, Ikeda Keiko, Ajito Tadaharu, Suzuki Kazuyuki
Large Animal Technical Services Team, Nippon Zenyaku Kogyo Tokyo Branch Office, 1-2-5 Kandasurugadai, Chiyoda, Tokyo 101-0062, Japan.
School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan.
J Vet Med Sci. 2021 May 17;83(5):814-818. doi: 10.1292/jvms.20-0716. Epub 2021 Mar 26.
The aims of studies were to estimate the withdrawal period of antibiotic from milk after the intramammary infusion of cefazolin sodium (CEZ) in cows with difficulties in frequent milk discharge due to disease such as teat injury. The period was compared among cows milked twice a day after 150 or 450 mg of CEZ were administered to all quarters (Study 1, 2) and the cows in which milking of front-right quarter was ceased for five days after administration of these infusions to only that quarter (Study 3). In Studies 1 and 2, the median of 17.66 µg/ml and 83.18 µg/ml of CEZ were detected in the samples of first milking after intramammary administration, respectively; however, there was no residual antibiotic by 72 hr in all cows. In Study 3, the median of 1.96 µg/ml of CEZ was detected in the sample after the resumption of milking at 120 hr, and the residual was eliminated by 174 hr. The withdrawal period may be prolonged by the cessation of milking after administration, and the period is the total time from cessation to 72 hr after the resumption of milking.
研究目的是评估在患有诸如乳头损伤等疾病导致频繁排乳困难的奶牛中，经乳房内注入头孢唑林钠（CEZ）后牛奶中的抗生素停药期。在所有乳区分别给予150或450毫克CEZ后，对每天挤奶两次的奶牛进行该停药期比较（研究1、2），以及仅对右前乳区给予这些注入剂后停止该乳区挤奶五天的奶牛进行比较（研究3）。在研究1和2中，乳房内给药后首次挤奶的样本中分别检测到CEZ的中位数为17.66微克/毫升和83.18微克/毫升；然而，所有奶牛在72小时时均无抗生素残留。在研究3中，在120小时恢复挤奶后的样本中检测到CEZ的中位数为1.96微克/毫升，并且在174小时时残留被清除。给药后停止挤奶可能会延长停药期，该停药期是从停止挤奶到恢复挤奶后72小时的总时长。
