Streptococci and enterococci as animal pathogens

Chanter, N.

doi:10.1046/j.1365-2672.83.s1.11.x

Cited by 45 publications

(36 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…S. zooepidemicus is a significant secondary pathogen in the horse (12), and it was isolated from the trachea of 66% of horses with IAD, with samples in 30% of cases having Ն10 3 CFU/ml. Disease (51), including pneumonia (61), has been reproduced experimentally in the horse, although we are unaware of any reports in the literature of experimental reproduction of IAD.…”

Section: Discussionmentioning

confidence: 99%

Association between Respiratory Disease and Bacterial and Viral Infections in British Racehorses

et al. 2005

Self Cite

View full text Add to dashboard Cite

Respiratory disease is important in horses, particularly in young Thoroughbred racehorses, and inflammation that is detected in the trachea and bronchi (termed inflammatory airway disease [IAD]) is more significant in this population in terms of impact and frequency than other presentations of respiratory disease. IAD, which is characterized by neutrophilic inflammation, mild clinical signs, and accumulation of mucus in the trachea, may be multifactorial, possibly involving infections and environmental and immunological factors, and its etiology remains unclear. This 3-year longitudinal study of young Thoroughbred racehorses was undertaken to characterize the associations of IAD and nasal discharge with viral and bacterial infections. IAD was statistically associated with tracheal infection with Streptococcus pneumoniae (capsule type 3), Streptococcus zooepidemicus, Actinobacillus spp., and Mycoplasma equirhinis and equine herpesvirus 1 and 4 infections, after adjustment for variation between training yards, seasons, and age groups. The association with S. pneumoniae and S. zooepidemicus was independent of prior viral infection and, critically, was dependent on the numbers of organisms isolated. S. pneumoniae was significant only in horses that were 2 years old or younger. The prevalence and incidence of IAD, S. zooepidemicus, and S. pneumoniae decreased in parallel with age, consistent with increased disease resistance, perhaps by the acquisition of immunity. The study provided evidence for S. zooepidemicus and S. pneumoniae playing an important etiological role in the pathogenesis of IAD in young horses.Respiratory disease is common in racehorses in training (10,15,29), as it is in most young domestic animals species. Both the incidence and prevalence of respiratory disease in racehorses vary widely between yards and between years (38, 46, 58), but the reasons underlying this variation, including the causes of the disease, are not defined.Inflammatory lower airway disease (IAD), which is usually associated with increased amounts of mucus visible in the trachea after exercise and increased proportions of inflammatory cells (44), is common in young racehorses around the world, despite marked differences in management and climate. Clinical signs associated with IAD include coughing (10, 16) and poor performance in racing (30,37,44,45). IAD is considerably more common than signs of upper respiratory disease and in young racehorses has a mean monthly prevalence of around 12% and an incidence of around 10 cases/100 horses/month (10, 58). The mean duration of each incident is around 8 weeks, and the disease is often recurrent in individuals. The monthly prevalence and incidence of signs of upper respiratory disease are around 5% and 5 cases/100 horses/month (10, 38, 58).The etiology and pathogenesis of IAD are poorly defined, but the etiology is probably multifactorial (10, 44). Studies focusing on individual agents suggest the possible involvement of viral infection (59), bacterial infection (10,14,16,42,43,56), and...

show abstract

Section: Discussionmentioning

confidence: 99%

Association between Respiratory Disease and Bacterial and Viral Infections in British Racehorses

et al. 2005

Self Cite

View full text Add to dashboard Cite

show abstract

“…Streptococci have been isolated from a wide range of environments and can be found as part of the normal flora of the skin and alimentary, respiratory and genito-urinary tracts of humans and different animals (Kilian, 1998). Some Streptococcus species have been implicated as the causes of different diseases in humans and animals, such as endometritis, respiratory infections, endocarditis, meningitis, arthritis and mastitis (Chanter, 1997;Köhler, 2007).…”

mentioning

confidence: 99%

Streptococcus porci sp. nov., isolated from swine sources

Vela

Zamora²,

Palacios³

et al. 2010

International Journal of Systematic and Evolutionary Microbiology

View full text Add to dashboard Cite

Two unidentified Gram-positive, catalase-negative, coccus-shaped organisms were recovered from pigs and subjected to a polyphasic taxonomic analysis. Based on cellular morphology and biochemical criteria, the isolates were tentatively assigned to the genus Streptococcus, although the organisms did not appear to correspond to any recognized species. Comparative 16S rRNA gene sequence studies confirmed this identification and showed that the nearest phylogenetic relatives of the unknown cocci were

show abstract

“…Nearly 30% of all reported equine infections worldwide may be attributable to this organism (8). Strangles is so called because of the pharyngeal constriction which occurs as a consequence of lymph node swelling (often accompanied by abscess formation) in the upper respiratory tract of the horse following the spread of infection from the nasopharynx.…”

mentioning

confidence: 99%

Mutation of the Maturase Lipoprotein Attenuates the Virulence ofStreptococcus equito a Greater Extent than Does Loss of General Lipoprotein Lipidation

et al. 2006

View full text Add to dashboard Cite

Streptococcus equi is the causative agent of strangles, a prevalent and highly contagious disease of horses. Despite the animal suffering and economic burden associated with strangles, little is known about the molecular basis of S. equi virulence. Here we have investigated the contributions of a specific lipoprotein and the general lipoprotein processing pathway to the abilities of S. equi to colonize equine epithelial tissues in vitro and to cause disease in both a mouse model and the natural host in vivo. Colonization of air interface organ cultures after they were inoculated with a mutant strain deficient in the maturase lipoprotein (⌬prtM 138-213 , with a deletion of nucleotides 138 to 213) was significantly less than that for cultures infected with wild-type S. equi strain 4047 or a mutant strain that was unable to lipidate preprolipoproteins (⌬lgt 190-685 ). Moreover, mucus production was significantly greater in both wild-type-infected and ⌬lgt 190-685 -infected organ cultures. Both mutants were significantly attenuated compared with the wild-type strain in a mouse model of strangles, although 2 of 30 mice infected with the ⌬lgt 190-685 mutant did still exhibit signs of disease. In contrast, only the ⌬prtM 138-213 mutant was significantly attenuated in a pony infection study, with 0 of 5 infected ponies exhibiting pathological signs of strangles compared with 4 of 4 infected with the wild-type and 3 of 5 infected with the ⌬lgt 190-685 mutant. We believe that this is the first study to evaluate the contribution of lipoproteins to the virulence of a gram-positive pathogen in its natural host. These data suggest that the PrtM lipoprotein is a potential vaccine candidate, and further investigation of its activity and its substrate(s) are warranted.

show abstract

Streptococci and enterococci as animal pathogens

Cited by 45 publications

References 5 publications

Association between Respiratory Disease and Bacterial and Viral Infections in British Racehorses

Association between Respiratory Disease and Bacterial and Viral Infections in British Racehorses

Streptococcus porci sp. nov., isolated from swine sources

Mutation of the Maturase Lipoprotein Attenuates the Virulence ofStreptococcus equito a Greater Extent than Does Loss of General Lipoprotein Lipidation

Contact Info

Product

Resources

About