The aims of this prospective and descriptive study were to: (a) characterize treatment profile and quantify antimicrobial consumption for treatment of clinical mastitis (CM) in dairy herds of Brazil; and, (b) determine the association of antimicrobial use (AMU) for treatment of CM and herd-level descriptors, such as herd size, average milk yield, bulk milk somatic cell count (BMSCC), bulk milk total bacterial count (BMTBC), season and housing type. Data on treatment practices were obtained from 19 of 20 dairy herds selected for the study for a period of 12 months per herd. Treatment protocols were recorded in each case of CM by the farm personnel using a form that included information at the cow- and treatment-level. The frequency of antimicrobial consumption for treatment of CM was determined monthly in units of defined daily dose (DDD) and expressed as antimicrobial treatment incidence (ATI; the number of DDD per 1,000 lactating cow-days). Mixed linear regression models were used to determine the association between log-transformed ATI and herd level descriptors. The overall monthly mean ATI was 21.9 DDD per 1,000 lactating cow-days (15.4 DDD per 1,000 lactating cow-days for intramammary compounds, and 6.4 DDD per 1,000 lactating cow-days for systemically administered antimicrobials). Among intramammary drugs, aminoglycosides had the highest ATI (11.7 DDD per 1,000 lactating cow-days), followed by a treatment with a combination of tetracycline, aminoglycoside and polypeptide (10.3 DDD per 1,000 lactating cow-days). For systemically administrated antimicrobials, fluoroquinolones (6.1 DDD per 1,000 lactating cow-days), penicillin combinations (3.9 DDD per 1,000 lactating cow-days), and the combination of sulfonamide and pyrimidine (3.6 DDD per 1,000 cows per day) were the most frequently used antimicrobials. The use of combination therapy (i.e., association of intramammary and systemically administered antimicrobials) was reported for 64.3 % of treatments at the cow-level. The AMU tended to be higher in herds with highest BMSCC. In addition, a higher AMU for treatment of CM was observed during the rainy season compared to the dry season in Brazil. This seasonal effect was mostly characteristic in herds housing cows in outdoor housing systems (i.e., paddocks).

中文翻译：

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抗菌药物用于治疗巴西乳牛群中的临床乳腺炎及其与牛群水平指标的关联。

这项前瞻性和描述性研究的目的是：（a）表征治疗概况并量化用于治疗巴西乳牛群临床乳腺炎（CM）的抗生素消耗量；（b）确定用于治疗CM的抗微生物药物（AMU）的相关性和牛群水平的描述因素，例如牛群大小，平均产奶量，散装牛奶体细胞计数（BMSCC），散装牛奶总细菌数（BMTBC） ，季节和房屋类型。从为研究选择的20个乳牛群中的19个获得了有关治疗实践的数据，每个牛群为期12个月。农场工作人员在每种CM情况下都使用包括奶牛和治疗级别信息的表格记录了治疗方案。每月以确定的日剂量（DDD）为单位确定用于治疗CM的抗菌药物消耗的频率，并表示为抗菌药物治疗的发生率（ATI；每1000头泌乳牛日的DDD数量）。混合线性回归模型用于确定对数转换的ATI和畜群水平描述符之间的关联。总体月平均ATI为每1000头泌乳牛天21.9 DDD（对于乳房内化合物，每1000头泌乳牛天15.4 DDD，而每1000头泌乳牛天6.4 DDD对于系统施用的抗菌剂）。在乳内药物中，氨基糖苷类药物的ATI最高（每1000头泌乳牛天11.7 DDD），随后是四环素，氨基糖苷和多肽的组合治疗（每1000头泌乳牛天10.3 DDD）。对于全身给药的抗菌药物，氟喹诺酮类药物（每1000头奶牛日6.1 DDD），青霉素组合（每1000头奶牛日3.9 DDD）和磺酰胺和嘧啶的组合（每1000头奶牛3.6 DDD）是最常见的用过的抗菌药。据报道，在奶牛水平上，联合治疗（即乳内和全身施用抗菌药物的联合使用）占治疗的64.3％。BMSCC最高的牛群中的AMU往往较高。另外，与巴西的旱季相比，在雨季期间观察到较高的ACM用于治疗CM。这种季节性影响在室外住房系统（即牧场）的牛群饲养中最为典型。000泌乳牛日）和磺酰胺和嘧啶的组合（每天每1000头母牛3.6 DDD）是最常用的抗微生物剂。据报道，在奶牛水平上，联合治疗（即乳内和全身施用抗菌药物的联合使用）占治疗的64.3％。BMSCC最高的牛群中的AMU往往较高。另外，与巴西的旱季相比，在雨季期间观察到较高的ACM用于治疗CM。这种季节性影响在室外住房系统（即牧场）的牛群饲养中最为典型。000泌乳牛日）和磺酰胺和嘧啶的组合（每天每1000头母牛3.6 DDD）是最常用的抗微生物剂。据报道，在奶牛水平上，联合治疗（即乳内和全身施用抗菌药物的联合使用）占治疗的64.3％。BMSCC最高的牛群中的AMU往往较高。另外，与巴西的旱季相比，在雨季期间观察到较高的ACM用于治疗CM。这种季节性影响在室外住房系统（即牧场）的牛群饲养中最为典型。据报道，在奶牛水平上，有64.3％的患者接受了乳内和全身给药的抗菌药物联合治疗。BMSCC最高的牛群中的AMU往往较高。另外，与巴西的旱季相比，在雨季期间观察到较高的ACM用于治疗CM。这种季节性影响在室外住房系统（即牧场）的牛群饲养中最为典型。据报道，在奶牛水平上，有64.3％的患者接受了乳内和全身给药的抗菌药物联合治疗。BMSCC最高的牛群中的AMU往往较高。另外，与巴西的旱季相比，在雨季期间观察到较高的ACM用于治疗CM。这种季节性影响在室外住房系统（即围场）的牛群饲养中最为典型。