Brucella blood agar with hemin and vitamin k1

Brain and liver tissues from all five birds were tested in-house for the presence of Usutu virus (Flavivirus) using a reverse transcription (RT) PCR proceeding according to Pisano et al. (in preparation). The same samples were tested using West-Nile Virus (Flavivirus) qPCR adapted from Eiden et al. (2010).
Skin, muscle, and liver samples of two nestlings (Colony B and C) were submitted to Laboklin GMBH & CO.KG (97688 Bad Kissingen, Deutschland) for Polyomavirus (Avipolyomavirus) and Beak and feather disease virus (Circovirus) detection using real-time PCR.
Skin, lung, and spleen samples from one nestling (Colony B) and liver, lung and spleen from a second nestling (Colony C) were submitted to the Institute of Bacteriology, University of Bern, Switzerland, for anaerobic, Salmonella spp. and Yersinia spp. cultures. BD™ Brucella Blood Agar with Hemin and Vitamin K1 (Becton Dickinson GmbH, Heidelberg, Germany), Brilliance™ Salmonella (Oxoid Limited, United Kingdom) and Yersinia Selective Agar (Oxoid Limited, United Kingdom) were used respectively.

Bacterial suspensions and MIC gradient stripes containing erythromycin, vancomycin, metronidazole, tetracycline and clindamycin (bioMérieux, Marcy l'Etoile, France; Oxoid; Himedia) were plated onto BD™ Brucella Blood Agar with Hemin and Vitamin K1 (Becton Dickinson) following the manufacturer's instructions. According to the recommendations of the Clinical and Laboratory Institute (CLSI), the following breakpoints for resistance were used: erythromycin and clindamycin 8 mg/L, tetracycline 16 mg/L, metronidazole 32 mg/L (CLSI, 2021 ; Spigaglia et al., 2011 (link)). CLSI‐approved clinical breakpoints for vancomycin were not available. The reference strain C. difficile ATCC®700057 was used as quality control strain.