Short communication: Subtyping of Staphylococcus haemolyticus isolates from milk and corresponding teat apices to verify the potential teat-skin origin of intramammary infections in dairy cows.

Coagulase-negative staphylococci (CNS) are a major cause of intramammary infections (IMI) in dairy cows and they colonize the teat skin. Staphylococcus haemolyticus, one of the more common CNS, has been identified as a highly versatile opportunistic species. The aim of the present study was to gain better insight into the adaptation of S.

Antibacterial activities of coagulase-negative staphylococci from bovine teat apex skin and their inhibitory effect on mastitis-related pathogens.

Aims: To explore antibacterial activities of coagulase-negative staphylococci (CoNS) from teat apices of dairy cows towards mastitis-causing pathogens.

Methods And Results: Of 254 CoNS, 38 displayed bacteriocin-like activity after a first screening. Seven of these strains displayed activity against at least one mastitis-related pathogen (Streptococcus uberis, Streptococcus dysgalactiae and Staphylococcus aureus).

Unraveling the microbiota of teat apices of clinically healthy lactating dairy cows, with special emphasis on coagulase-negative staphylococci.

Swab samples (n=72) obtained from the teat apex of lactating dairy cows without visual signs of inflammation (n=18) were gathered on 2 well-managed Flemish dairy herds (herds 1 and 2) during the same month to assess the bacterial diversity of teat apices before milking. A combination of both culture-dependent [plating and (GTG)(5)-PCR fingerprinting of the colonies] and culture-independent [denaturing gradient gel electrophoresis (PCR-DGGE)] techniques indicated that the teat apices contain a wide diversity of bacterial genera. Despite a low bacterial load, 20 bacterial genera of 3 phyla (Actinobacteria, Firmicutes, and Proteobacteria) were present.

Characterization of coagulase-negative staphylococcus species from cows' milk and environment based on bap, icaA, and mecA genes and phenotypic susceptibility to antimicrobials and teat dips.

The aim of this study was to investigate whether the main coagulase-negative staphylococci (CNS) species involved in bovine intramammary infections (IMI) possess specific characteristics that promote colonization of the udder. Virulence markers associated with biofilm formation, antimicrobial resistance, and biocide tolerance were compared between typically contagious CNS species (Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus haemolyticus, and Staphylococcus simulans) and those rarely causing IMI (Staphylococcus sciuri, Staphylococcus equorum, and others) to find possible associations with pathogenicity. Coagulase-negative staphylococci isolates (n=366) belonging to 22 different species were analyzed by PCR for the presence of the biofilm-associated genes bap and icaA, and the methicillin resistance gene mecA.

Culture-independent exploration of the teat apex microbiota of dairy cows reveals a wide bacterial species diversity.

Due to their close proximity to the mammary gland tissue, the bacterial communities lining the teat apex of the udders from lactating cows influence udder health. Denaturing gradient gel electrophoresis of the amplified V3 variable region of the 16S rRNA gene was used as a culture-independent method to reveal the bacterial composition of 48 samples originating from the teat apices of twelve Friesian-Holstein dairy cows suffering from clinical mastitis in one quarter. The microbiota belonged to four bacterial phyla: the Actinobacteria (32% of all genera), the Bacteroidetes (1%), the Firmicutes (42%), and the Proteobacteria (25%), encompassing 17 bacterial genera.