جستجوی مقالات مرتبط با کلیدواژه « Leptospira interrogans » در نشریات گروه « دامپزشکی »

Environmental and hosts risk factors are considered as two essential elements in epidemiological studies of infectious diseases. The severity of the infection and also the chance of transmission of pathogenic Leptospira interrogans bacteria from herbivores to humans have always been exposed to environmental and hosts risk factors. This study aimed to investigate the presence of serum reaction in the equid's population of Lorestan province and the determination of native serovars as well as evaluation of the role of environmental and host factors on seroprevalence. A total of 327 equids including 223 horses, 46 mules, and 58 donkeys were sampled and sera samples evaluated against 7 different Leptospira interrogans serovars. Geographical location and environmental conditions of sampled areas were recorded to be used in statistical surveys. The results showed that the serum positive reaction rate in horses, mules, and donkeys was 18.38, 10.87 and 3.45%, respectively. Host risk factors such as sex, age, and breed were effective on serum response rate and a significant difference was found. Canicola serovar with 46.34, 100 and 60% infection in horses, donkeys, and mules, respectively was the most common infective serovar; but a significant difference was not observed between animal species. Also, the results indicated that annual temperature of the environment and altitude at sea level of sampled location have a significant effect on seroprevalence of leptospirosis, but relative humidity and annual rainfall did not have a significant effect. Results of the current study proved that infection with Leptospira interrogans, although in Lorestan province is less severe than in other parts of the country, the most important native serovar of this region is canicola.

Leptospira interrogans is the cause of leptospirosis, a common disease among humans and animals. One of the most important recommendations of international associations concerned with laboratory animals, is the use of defined animals. Based on the recommendation of the FELASA, the diagnostic monitoring is required to evaluate the contamination of animals to different microbial agents. In this study, the prevalence of this bacteria was investigated in a colony of NIH strain laboratory mice of laboratory animal breeding unit at the Razi Institute in 1396.74 adult mice (in the range of 30-35g and age 6-8 weeks) were randomly selected from both sexes in breeding colony and 6 wild mice were selected by means of live traps from the outside of facility. After ethical euthanasia and autopsy, samples were taken from their kidney tissues and after preparation, the PCR method was performed using Leptospira interrogans specific primers. Designing and preparing the positive control was carried out using plasmid (pGEM -T easy vector) transformation containing the pathogenic of Leptospira interrogans gene (LipL32) in E.coli for gene amplification and extraction. No positive cases were observed from the examined samples. According to FELASA instructions, it can be concluded that with 99.9% confidence, the Leptospira interrogans infection in breeding salons of Razi Institute NIH mice was discarded.

In order to evaluate the seroprevalence of Leptospira interrogans infection in horses, blood samples were taken from 152 horses from 7 horse clubs in Tehran. Serum samples were examined using a microscopic agglutination test to detect the presence of antibodies against five live serotypes of Leptospira interrogans (grippotyphosa, pomona, icterohaemorrhagiae, canicula and hardjo). Of the tested samples, 23 horses (15/13%) were positive to one or more serotypes. Titer levels ranged from 1:100 to 1:200. Icterohaemorrhagiae (44/44%) was the most frequently detected serovar followed in descending order by gripotyphosa (29/62%), canicula (22/22%), pomona (3/7%) and serotype hardjo was negative. Statistical analysis using the chi-squared test showed there was no significant correlation differences between Leptospira interrogans infection and factors such as sex and age. The serum titers of infected horses ranged from 1:100 (n=19) to 1:200 (n=78). These results suggest that the icterohaemorrhagiae serovar may be the most prevalent serovar in the horse population Tehran.

Leptospirosis is the most important zoonosis disease that is caused by Leptospira interrogans serovars. Leptospirosis is relatively mild and without any specific clinical signs in the horse, except for blindness due to recurrent uveitis. However, horses plays potential zoonotic role in human health. The aim of this study was to determination of seroprevalence of anti-leptospiral antibodies against six Leptospira serovars in stallions of Tabriz area. Examination of sera obtained from forty male horses were examined using MAT, revealed that 85 percent of animals were seropositive. The highest number of reactors in horses (65%) were due to serovar tarasovi, followed in descending order by australis (50%), icterohaemorrhagiae (25%), pomona (10%) and grippothyphosa (5%) and hardjo (5%). Eight horses had antibodies against one serovar, eighteen horses had against two serovar and six horses had specific antibodies against three serovars. Basis on age grouping of the horses, seropositive animals were 100 percent in 5-10 years, 80 percent in 10-15 years and 77.7 percent in 15-20 years old group. This differences was statically significant (P<0.05). Only four horses had specific antibodies against Leptospira in the aqueous humor of the eyes, which all belong to right eyes. In these positive animals, antibodies were against Leptospira interrogans serovar tarasovi with 1:100 titers. All four horses were seropositive, too. Five horses had signs of ocular involvement and blindness; only two and three horses had specific antibodies against Leptospira serovars in the aqueous humor of the eye and serum, respectively. Result of this study suggested that there were leptospiral infections in horse populations of Tabriz area, which is an important zoonotic and is an occupational hazard to horse owner, farmers, and veterinarians.