Cognosco, AnexaFVC, Morrinsville 3300, New Zealand.
Cognosco, AnexaFVC, Morrinsville 3300, New Zealand.
J Dairy Sci. 2019 May;102(5):4376-4386. doi: 10.3168/jds.2018-15141. Epub 2019 Mar 14.
The objectives of this study were to evaluate the efficacy of therapy of clinical mastitis following intramammary infusion of 2 durations of intramammary antibiotic therapy and to analyze clinical and microbiology data at enrollment or within 4 d of commencement of treatment as potential predictors of subsequent clinical and bacteriological cure. A total of 304 glands were randomly assigned to intramammary treatment with a combination of amoxicillin, clavulanic acid, and prednisolone either 3 times at 12-h intervals (3×12, n = 156) or 5 times at 12-h intervals (5×12 hourly, n = 148). At enrollment (d 0), assessments were made of the cow's demeanor, rectal temperature, teat-end hyperkeratosis, presence of heat or swelling of the gland, presence of clots in the milk, and California Mastitis Test (CMT) score. Cows were revisited on d 4, 14, and 21 and assessed for rectal temperature, the presence of clots in milk, heat or swelling of the gland, and CMT score. Milk samples were collected from enrolled glands for bacteriology (d 0, 4, 14, and 21) and for somatic cell count (d 14 and 21). Data were analyzed using generalized linear models. Treatment group was the key independent variable, but herd was included in the models. Other potentially confounding variables were included where associated at the bivariate level. A second series of analyses were undertaken to predict likelihood of clinical and bacteriological cure using the clinical signs cow age and days in milk, as well as bacteriological results at d 0 and 4. Although we found a higher clinical failure rate in the 3×12 than 5×12 hourly treatment group (28.2 ± 5.0 vs. 13.4 ± 3.6%, respectively), we noted no difference in bacteriological cure percentage (73.3 ± 7.8 vs. 72.0 ± 7.4%, respectively). The presence of heat or swelling at d 4, days in milk at initiation of treatment, age of the cow, and change in CMT score between d 0 and 4 were predictive of clinical and bacteriological cure. We concluded that increasing the duration of treatment resulted in significantly fewer clinical failures, but had no effect on cure proportion, somatic cell count, or new infection rate. Knowledge of cow age and days in milk and clinical signs were predictive of clinical and bacteriological cure proportion and may provide guidance for producers, under veterinary direction, as to when to extend or recommence therapy.
本研究的目的是评估在临床乳腺炎中通过两种不同时间间隔的乳房内抗生素治疗方案进行治疗的疗效，并分析在入组时或治疗开始后 4 天内的临床和微生物学数据，以作为后续临床和细菌学治愈的潜在预测指标。共 304 个腺体被随机分配到阿莫西林、克拉维酸和泼尼松龙的乳房内治疗中，治疗方案为 12 小时间隔 3 次（3×12，n=156）或 12 小时间隔 5 次（5×12 小时，n=148）。在入组时（d0），评估牛的行为、直肠温度、乳突末端过度角化、腺体发热或肿胀、乳中存在凝块以及加利福尼亚乳房炎测试（CMT）评分。在 d4、14 和 21 时对奶牛进行回访，并评估直肠温度、乳中凝块、腺体发热或肿胀以及 CMT 评分。从入组的腺体中采集奶样进行细菌学（d0、4、14 和 21）和体细胞计数（d14 和 21）。使用广义线性模型进行数据分析。治疗组是关键的独立变量，但同时考虑了畜群。在二元水平上存在关联的其他潜在混杂变量也被包括在内。进行了第二次分析，以使用临床体征（牛的年龄和泌乳天数）以及 d0 和 d4 的细菌学结果来预测临床和细菌学治愈的可能性。尽管我们发现 3×12 小时治疗组的临床失败率高于 5×12 小时治疗组（分别为 28.2%±5.0%和 13.4%±3.6%），但我们没有发现细菌学治愈率的差异（分别为 73.3%±7.8%和 72.0%±7.4%）。d4 时的发热或肿胀、治疗开始时的泌乳天数、牛的年龄以及 d0 至 d4 之间 CMT 评分的变化是临床和细菌学治愈的预测指标。我们得出结论，增加治疗时间会显著减少临床失败，但对治愈率、体细胞计数或新感染率没有影响。牛的年龄和泌乳天数以及临床症状的知识可以预测临床和细菌学治愈率，并可能为生产者提供指导，以在兽医指导下决定何时延长或重新开始治疗。
