The temporal relationship of fecal shedding of Lawsonia intracellularis and seroconversion in field cases
نویسنده
چکیده
The use of the immunoperoxidase monolayer assay (IPMA) has been limited to challenge model investigations10–11 and a few field studies. Guedes et al12 reported 100% specificity and 89% sensitivity at a serum dilution of 1:30 for the IPMA serological test. Guedes et al13 also determined that there was 98.6% agreement between the IFAT and the IPMA tests in experimentally infected pigs, concluding that both serological tests provide similar results. These studies show that the IPMA is a good herd level test to identify exposure to LI, but the period of fecal shedding has not been related to the time of seroconversion in field studies. To improve control strategies, practitioners must be able to use serological tests to estimate when LI is being shed in a herd, which requires an understanding of the interval between fecal shedding and seroconversion under field conditions.
منابع مشابه
Efficacy of gallium maltolate against Lawsonia intracellularis infection in a rabbit model.
Antimicrobial efficacy against Lawsonia intracellularis is difficult to evaluate in vitro, thus, the effects of gallium maltolate's (GaM) were investigated in a rabbit model for equine proliferative enteropathy (EPE). Juvenile (5-6-week-old) does were infected with 3.0 × 10(8) L. intracellularis/rabbit and allocated into three groups (n = 8). One week postinfection, one group was treated with G...
متن کاملTemporal detection of Lawsonia intracellularis using serology and real-time PCR in Thoroughbred horses residing on a farm endemic for equine proliferative enteropathy.
The goals of this study were to evaluate titers of antibodies against Lawsonia intracellularis in 68 resident broodmares from a farm known to be endemic for equine proliferative enteropathy (EPE) and to evaluate maternal antibodies, occurrence of seroconversion and fecal shedding in their foals. Serum samples collected from mares at delivery and from foals pre- and post-colostrum ingestion and ...
متن کاملEvidence of host adaptation in Lawsonia intracellularis infections
BACKGROUND Lawsonia intracellularis is the causative agent of proliferative enteropathy, an endemic disease in pigs and an emerging concern in horses. Enterocyte hyperplasia is a common lesion in every case but there are differences regarding clinical and pathological presentations among affected species. We hypothesize that host susceptibility to L. intracellularis infection depends on the spe...
متن کاملEffect of oral tiamulin on the development of porcine proliferative enteropathy in a pure-culture challenge model
Methods: Thirty-two pigs were allocated to two replications of four treatments, each replication with four pigs per treatment; 1) noninfected and nonmedicated (CONTROL); 2) infected and nonmedicated(I-NM); 3) infected and medicated with feed containing tiamulin hydrogen fumarate (thf ) at 35 g per ton (I-35); and 4) infected and medicated with feed containing thf at 50 g per ton (I-50). These d...
متن کاملEvaluation of the humoral immune response and fecal shedding in weanling foals following oral and intra-rectal administration of an avirulent live vaccine of Lawsonia intracellularis.
Equine proliferative enteropathy (EPE) caused by Lawsonia intracellularis has recently been recognized as an emerging disease in foals. Whilst the clinical entity, diagnostic evaluation and treatment of affected foals have been well established and described, preventive measures for EPE have remained largely unaddressed. The objectives of this study were to investigate the humoral immune respon...
متن کامل