The occurrence of Chlamydiaspp. in pigs with and without clinical disease

Abstract

BackgroundWithin the genera Chlamydia, the development of refined diagnostic techniques has allowed the identification of four species that are capable of infecting pigs. The epidemiology, clinical, and zoonotic impacts of these species are however largely unknown. The study aimed to investigate the presence of Chlamydia spp. in the intestines of growing pigs and in conjunctival swabs from finisher pigs, and relate the findings to clinical signs.ResultsBy histology, 20 of 48 pigs had intestinal lesions that may be consistent with chlamydial infection. By PCR, forty-six of the pigs were positive whereas two samples were inhibited. Sequencing of 19 DNA extracts identified these as Chlamydia suis. By immunohistochemistry, 32 of 44 samples were positive and a significant relationship was detected between macroscopically visible intestinal lesions and a high degree of infection. By real-time PCR, a significant difference was detected between pigs with and without conjunctivitis when a Ct value of 36 was employed but not when a Ct value of 38 was employed.ConclusionsChlamydia suis was demonstrated in most samples and overall, no correlation to clinical signs was detected. However, a correlation was noted between samples with a high degree of infection and the presence of clinical signs. It is possible, that the intensive pig production systems studied might predispose for the transmission and maintenance of the infection thus increasing the infectious load and the risk for disease in the pig.

Chlamydia felis exposure in companion dogs and cats in Lanzhou, China: a public health concern

“…In addition to in cats, a high prevalence of Chlamydia has been found in growing pigs with or without clinical diseases [22], and chlamydial infections occur frequently in German sheep flocks, even in the absence of elevated abortion rates [23]. Reports of canine chlamydiosis are not common, possibly because C. felis is rarely considered to be a disease-causing pathogen in dogs.…”

Development of aChlamydia suis-specific antibody enzyme-linked immunosorbent assay based on the use of a B-cell epitope of the polymorphic membrane protein C

“…Chlamydia suis is currently considered to be the most prevalent chlamydial species in pigs but pigs also can become infected by C. pecorum , C. abortus and C. psittaci (reviewed by Schautteet & Vanrompay, ). Chlamydia suis in pigs has been associated with asymptomatic infections but also with a variety of clinical symptoms such as conjunctivitis, rhinitis, pneumonia, enteritis, reproductive disorders such as irregular return to oestrus, early embryonic dead in inseminated sows and inferior semen quality in boars (decrease in sperm cell motility and death of sperm cells) (reviewed by Chahota et al., ; Englund, Segerstad, Arnlund, Westergren, & Jacobson, ; Hoffmann et al., ; Rypula et al., ; Schautteet, & Vanrompay, ; Schautteet et al., ). Differences in clinical symptoms and pathology caused by C. suis are thought to be due to a high degree of genetic diversity in C. suis .…”

Occurrence of reproductive disorders in pig herds with and withoutChlamydia suisinfection – statistical analysis of breeding parameters

“…Of these, the species detected in pigs include C. suis, C. abortus, C. psittaci, C. pecorum, and C. trachomatis (Kaufhold et al., ; Rypuła et al., ). These pathogens can cause clear manifestations of infections, as well as clinically asymptomatic disorders, which are only revealed during adverse environmental conditions and declining immunity (Englund, Af Segerstad, Arnlund, Westergren, & Jacobson, ; Rypuła, Niemczuk, Kumala, Płoneczka‐Janeczko, & Pejsak, ; Schauttet & Vanrompay, ). C. suis and C. abortus are primarily isolated in cases of reproductive disorders.…”