Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis at calving in dairy herds with suboptimal udder health

Abstract

Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis are common causes of bovine mastitis. To study these pathogens in early lactation, a 12-mo longitudinal, observational study was carried out in 13 herds with suboptimal udder health. The aims of the study were to investigate the occurrence of these pathogens and to identify if presence of the 3 pathogens, and of genotypes within the pathogens, differed with respect to herd, season, and parity. Quarter milk samples, collected at calving and 4 d in milk (DIM), were cultured for the 3 pathogens. Genotyping of staphylococcal and streptococcal isolates was performed using spa typing and pulsed-field gel electrophoresis, respectively. For each of the 3 pathogens, cows with an udder infection at calving or 4 DIM were allocated to 1 of 4 infection types: cleared (pathogen present only at calving), persistent (pathogen present in the same quarter at calving and 4 DIM), new (pathogen present only at 4 DIM), or cleared/new (pathogen present in 1 quarter at calving and in another quarter at 4 DIM). Associations between season or parity and overall occurrence of pathogens or infection types were determined using univariable mixed-effect logistic-regression models and the Fisher's exact test, respectively. The most commonly occurring pathogen was Staph. aureus, followed by Strep. dysgalactiae and Strep. uberis. Persistent infections were the most common infection type among Staph. aureus-infected cows, whereas cleared infections were the most common among Strep. dysgalactiae- and Strep. uberis-positive cows. The proportion of cows with persistent Staph. aureus infections and the proportion of cows having a Strep. uberis infection at calving or 4 DIM were higher in the multiparous cows than in primiparous cows. Infections with Strep. dysgalactiae were less common during the early housing season than during the late housing or pasture seasons, whereas persistent Strep. uberis infections were less common during the pasture season than during the late housing season. The relative occurrence of the 3 pathogens, infection types of each pathogen, and genotype diversity of each pathogen throughout the year or in different seasons and parities varied among the herds, indicating that underlying factors predisposing for udder infections at calving differ between herds. Genotyping of bacterial isolates gave important insight into how such infection patterns differed within and between herds. These findings emphasize the need to choose preventive strategies for each individual herd.

Characterization of Microbial Communities in a Dairy Farm Matrix in Ningxia, China, by 16S rDNA Analysis

“…The abundance of Staphylococcus in manure was higher than that in fresh feces and soil, the most important member of this genus being S. aureus . S. aureus is still described as one of the most frequently isolated etiological agents associated with bovine intramammary infections [51, 52], and some studies have shown a high incidence of S. aureus with genomic variation in resistance genes, which may pose a threat to public and animal health in Ningxia Province, China [53]. These pathogens displayed differences in antimicrobial resistance and could serve as carriers introducing antibiotic resistance genes into the food chain.…”

Genotypes of Staphylococcus aureus: On-farm epidemiology and the consequences for prevention of intramammary infections

“…In addition, this method is characterized by high resolution and is associated with the virulence gene pattern of bovine strains (Fournier et al, 2008;Graber et al, 2009;Cremonesi et al, 2015;. Besides RS-PCR, other subtyping methods have been used to further characterize staphylococcal IMI isolates such as spa typing (e.g., Boss et al, 2016;Lundberg et al, 2016), multilocus sequence typing (e.g., Hata et al, 2010;Boss et al, 2016), pulsed-field gel electrophoresis (e.g., Capurro et al, 2010;Cremonesi et al, 2015), and amplified fragment length polymorphism (Sakwinska et al, 2011). Their suitability for large clinical investigations, however, is mainly limited by low throughput or high cost.…”

Identification of staphylococci causing mastitis in dairy cattle from Algeria and characterization ofStaphylococcus aureus

“…Influences from breed, age and lactation stage of the animal have been described (Haftu et al ; Oliveira et al ). Staphylococcus aureus is one of the most important bacterial pathogens causing bovine mastitis (Tenhagen et al ; Wang et al ; Lundberg et al ; Srednik et al ). Mastitis caused by this bacterium has a lower cure rate than for most of the other bacteria (Sartori et al ; Srednik et al ).…”