Local host response following an intramammary challenge with Staphylococcus fleurettii and different strains of Staphylococcus chromogenes in dairy heifers. (December 2016)

• Record Type: Journal Article
• Authors: Piccart, Kristine; Verbeke, Joren; De Visscher, Anneleen; Piepers, Sofie; Haesebrouck, Freddy; De Vliegher, Sarne
• Is Part Of: Veterinary research. Volume 47:Number 1(2016)
• Page Start: 1
• Page End: 11
• Publication Date: 2016-12
• Subjects: Veterinary medicine -- Periodicals; Veterinary medicine -- France -- Periodicals; 636.089
• DOI: 10.1186/s13567-016-0338-9
• Languages: English
• ISSNs: 0928-4249

Abstract

Abstract Coagulase-negative staphylococci (CNS) are a common cause of subclinical mastitis in dairy cattle. The CNS inhabit various ecological habitats, ranging between the environment and the host. In order to obtain a better insight into the host response, an experimental infection was carried out in eight healthy heifers in mid-lactation with three different CNS strains: aStaphylococcus fleurettii strain originating from sawdust bedding, an intramammaryStaphylococcus chromogenes strain originating from a persistent intramammary infection (S. chromogenes IM) and aS. chromogenes strain isolated from a heifer's teat apex (S. chromogenes TA). Each heifer was inoculated in the mammary gland with 1.0 × 106 colony forming units of each bacterial strain (one strain per udder quarter), whereas the remaining quarter was infused with phosphate-buffered saline. Overall, the CNS evoked a mild local host response. The somatic cell count increased in allS. fleurettii -inoculated quarters, although the strain was eliminated within 12 h. The twoS. chromogenes strains were shed in larger numbers for a longer period. Bacterial and somatic cell counts, as well as neutrophil responses, were higher after inoculation withS. chromogenes IM than withS. chromogenes TA. In conclusion, these results suggest thatS. chromogenes might be better adapted to the mammary gland thanS. fleurettii . Furthermore, not allS. chromogenes strains induce the same local host response.