Shearer J K, Brown M B, Reed P A
Department of Preventive Medicine, College of Veterinary Medicine, University of Florida, Gainesville 32610.
Am J Vet Res. 1988 Feb;49(2):198-200.
Effects of source and washing of RBC on quantitative growth and hemolytic zone sizes of common bacterial pathogens of the bovine mammary gland were evaluated. Blood samples used to prepare the blood agar media were obtained from 10 adult dairy cows, 10 dairy calves, and 10 sheep. Hemolytic zone sizes produced by Staphylococcus aureus were significantly (P less than 0.01) larger on blood agar prepared with washed RBC than on blood agar prepared with nonwashed RBC, regardless of RBC source. With the exception of Corynebacterium bovis, growth of all bacteria was equivalent or significantly higher on medium prepared with washed RBC, compared with that on medium prepared with nonwashed RBC, regardless of RBC source. Significantly higher numbers of C bovis (P less than 0.01) and Streptococcus agalactiae (P less than 0.01) were isolated on medium prepared with washed cow RBC. Significantly higher numbers of Str uberis (P less than 0.01) and S aureus (P less than 0.05) were isolated on medium prepared with washed sheep RBC and washed calf RBC, respectively. Growth of Escherichia coli was not affected by the RBC source. Seemingly, RBC used in the preparation of medium should be washed. The source of RBC, as well as inter-animal variation, also should be considered in the quality control of medium.
评估了红细胞来源及洗涤对牛乳腺常见细菌病原体定量生长和溶血区大小的影响。用于制备血琼脂培养基的血样取自10头成年奶牛、10头犊牛和10只绵羊。无论红细胞来源如何，用洗涤过的红细胞制备的血琼脂上，金黄色葡萄球菌产生的溶血区大小显著（P<0.01）大于用未洗涤红细胞制备的血琼脂。除牛棒状杆菌外，无论红细胞来源如何，在以洗涤过的红细胞制备的培养基上，所有细菌的生长与用未洗涤红细胞制备的培养基相比相当或显著更高。在用洗涤过的奶牛红细胞制备的培养基上，分离出的牛棒状杆菌（P<0.01）和无乳链球菌（P<0.01）数量显著更多。在用洗涤过的绵羊红细胞和洗涤过的犊牛红细胞制备的培养基上，分别分离出显著更多的乳房链球菌（P<0.01）和金黄色葡萄球菌（P<0.05）。大肠杆菌的生长不受红细胞来源的影响。看来，制备培养基所用的红细胞应进行洗涤。在培养基的质量控制中，还应考虑红细胞来源以及动物个体差异。
