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Seroprevalence and Molecular Study of Toxoplasma Infection in Domestic Chickens from Khorramabad, Iran
2020
Ahmadi, Seyed Foad | Zarifi, Ozra | Shokrani, Hamidreza | Norouzian, Hassan
BACKGROUND: Toxoplasma gondii is an intracellular protozoan parasite that can infect most species of warm-blooded animals, including birds and humans. Because of feeding habits of domestic chickens, prevalence of Toxoplasma infection in free-range chickens is considered as a suitable indicator of environmental distribution of oocysts. OBJECTIVES: The present study was designed to investigate the seroprevalence of Toxoplasma infection in domestic chickens from Khorramabad and compare the results obtained from serological and molecular methods. METHODS: In total, 97 serum samples were randomly obtained from domestic chickens and examined for the presence of anti-Toxoplasmaantibodies using modified agglutination test (MAT). Fifty grams of muscles (mixture of breast and heart) and whole brain from seropositive chickens were separately homogenized and examined by PCR which targets the repeated element (RE) of the parasite. RESULTS: Anti-Toxoplasma antibodies were observed in 21 of 97 (21.64%) sera. T. gondii DNA was detected in 10 out of 21 (47.61%) seropositive chickens (with titres of ≥1:20). The low agreement between serological and molecular results can be explained by several factors such as possibility of cross-reactions in MAT and/or limited sample size in PCR. CONCLUSIONS: These results indicate that domestic chickens may have an important role as a source of infection for cats and individuals living in rural areas.
Afficher plus [+] Moins [-]Molecular detection of congenital toxoplasmosis in fetuses of slaughtered ewes in Khorramabad
2018
Taghizadeh, Zahra | Shokrani, Hamidreza | Sookhtehzari, Ali | Nayebzadeh, Hassan
BACKGROUNDS: Toxoplasma gondii is an intracellular parasite, which is widely prevalent in sheep throughout the world. Parasite infection can occur pre- or post-natally. Congenital ovine toxoplasmosis occurs following a primary infection in a pregnant ewe and leads to abortion and stillbirth of the fetus causing important economical losses to sheep industry. OBJECTIVES: The present study was conducted to evaluate the presence of T. gondii DNA in brain samples from fetuses of slaughtered ewes in Khorramabad, west of Iran. METHODS: In total, 60 brain samples of ovine fetuses were collected. Examined fetuses were categorized in three age groups (4 months). Fifty grams of each sample was homogenized by mortar and pestle. DNA extraction was performed using a DNA isolation kit (MBST, Iran). A polymerase chain reaction (PCR) which targets the repeated element (RE) of the organism was used for tissue samples. Brain samples were considered T. gondii-positive if the expected band size (529 bp) appeared. RESULTS: T. gondii was detected in 4 out of 60 (6·7%) examined fetuses. No case was recorded in the age group
Afficher plus [+] Moins [-]A Survey of Toxoplasma Gondii Infection in Aborted Fetuses of Sheep Using ELISA Method in Different Cities of North Khorasan Province
2019
Salehi, Mitra | Nezami, Hosein
BACKGROUND: Toxoplasma gondii is a zoonotic obligate intracellular protozoan parasite that infects all warm-blooded animals as well as human worldwide. Human is infected with Toxoplasma parasites by eating half-cooked meat of livestock or oocyte. OBJECTIVES: The purpose of this study was to determine the presence of Toxoplasma in aborted fetuses of sheep using the serological method in North Khorasan province. METHODS: In this study, from 2015 to 2017, 133 samples of the thoracic fluid in aborted fetuses of sheep from different cities of North Khorasan Province were collected and sent to the central laboratory of Bojnourd. For each sample, a questionnaire was prepared for gathering information such as age and city, and then, the antibody level was determined in each sample by ELISA method. RESULTS: In this study, the age of 133 aborted fetuses of sheep was more than 120 days. Also, of the 133 aborted fetuses of sheep, 14 samples (10.53%) were infected with Toxoplasma parasites. The highest and lowest rate of Toxoplasma infection was observed in 2016 and 2017, respectively. Also, the most infection was found in Shirvan and Faroj cities. Results of chi-square test showed that there was a significant difference between year and abortion in sheep due to infection with Toxoplasma parasite (P<0.05). There was not significant difference between the frequency of this parasite infection and aborted fetuses in different areas (P> 0.05). CONCLUSIONS: The results of this study indicate that Toxoplasma gondii infection is one of the causes of abortion of sheep in North Khorasan province, and sheep is one of important sources of meat and dairy products in this area, Therefore, observance of public health tips and the complete cooking of meat and boiling milk is emphasized.
Afficher plus [+] Moins [-]Correlation of tissue infection and serologic findings in pigs fed Toxoplasma gondii oocysts.
1985
Prickett M.D. | Dreesen D.W. | Waltman W.D. | Blue J.L. | Brown J.
On the distribution of Toxoplasma antibodies in Chejudo [Korea Republic]. 1: Distribution of Toxoplasma antibodies in swine, cats and butchers.
1989
Kim S.H. | Kim Y.J.
Effect of raising types and environmental conditions on the infection of Toxoplasma in the swine, the cat and the man were studied in Cheju Island from Sept. 1987 to Aug. 1988. Blood samples were taken from 214 conventionally raised swine in 6 villages and 506 swine raised in swine specialized farms, 122 cats raised under free moving or restrained conditions in 8 locations, 113 butchers, and 210 villagers. Toxoplasma antibody values of the blood sera were determined using the enzymelinked immunosorbent assay (ELISA). The eating type of viscera was also investigated by using questionnaires. When ELISA method was used, the percentage of Toxoplasma infect swine among the conventionally raised and of those raised in swine specialized farms were 60.7 % and 21.3 %, respectively. The respective antibody values (+- SD) were 0.589 (+- 0.310) and 0.385 (+- 0.237) and differed very significantly (p<0.01). A significant difference was also found in antibody values among 6 villages (p<0.05). The mean infection percentage of Toxoplasma in the cat was 38.2 %, the infection percentage for cats raised under free-moving and restrained condition were 37.0 % and 38.2 % respectively. The respective antibody values (+- SD) for Toxoplasma were 0.600 (+- 0.614) and 0.637 (0.645), and did not differ significantly. The infection percentage of Toxoplasma in villagers and butchers were 26.2 and 38.3 % respectively. The respective antibody values (SD) for toxoplasma were 0.429 (+- 0.195) and 0.341 (+- 0.236), and differed very significantly (p<0.01). There were also highly significant differences Pyo-sun and other village (p<0.01). Analysis of the questionnaires showed that 26.0 % of 392 villages ate liver and some villagers ate other viscera.
Afficher plus [+] Moins [-]Scanning electron microscopy on proliferative forms of Toxoplasma gondii and Sarcocystis species.
1988
Kang Y.B.
For the comparison of surface fine structures in the proliferative forms of two major protozoan parasites, Toxoplasma gondii and Sarcocystis species in mammalian hosts, isolated from the artificially infected mice and from the naturally infected cattle, respectively, an SEM(Hitachi S-570) was applied to the fixed, dried and coated with gold ion on the microslide glasses. The tachyzoites of T. gondii from the peritoneal cavity of the mouse showed the crescent-like feature and measured as 5.57 micro m in length and 2.33 micro m in width, while the bradyzoites of Sarcocystis species from the heart muscle of slaughtered cattle was banana-shaped and measured 14.18 micro m in length and 2.85 micro m in width. On the surface of Sarcocystis species bradyzoite, a distinct elliptical micropore was identified in the high magnification observation of 60,000X, and it measured as 0.35 micro m in length and 0.18 micro m in width.
Afficher plus [+] Moins [-]Zoonotic diseases diagnosed from Jan 2016 to Aug 2017 in Regional Veterinary Laboratories, Department of Veterinary Services, Malaysia
2018
Zulkifli A. | Santhi M. | Marzuki Z. | Rohana A. B. | Norasyikin A. | Tariq J. | Chandrawathani P. | Saira Banu M. R. | Faizah Hanim M. S.
Infectious diseases of livestockare a major threat to global animal health and welfare and their effective control is crucialfor agronomic health, for safeguarding and securing national and international food supplies and for alleviating rural povertyin developing countries. Some devastating livestock diseases are endemic in many parts of the world and threats from old and new pathogens continue to emerge, with changes to global climate, agricultural practices and demography presenting conditions that are especially favourable for the spread of arthropod-borne diseases into new geographical areas. Zoonotic infections that are transmissible either directly or indirectly between animals and humans are on the increase and pose significant additional threats to human health and the current pandemic status of new influenza A (H1N1) is a topical example of the challenge presented by zoonotic viruses (Tomley and Shirley, 2009). Malaysia, being one of the members of the World Organisation forAnimal Health (OIE) which is responsible for setting standards for control of animal diseases. For year 2017, the list included 116 animal diseases, infections and infestations, many of which are zoonotic in nature. As such, this paper discusses the commonzoonotic infections diagnosed in the five Regional Veterinary Laboratories which are spread across the country and entrustedto carry out diagnostic tests to aid in the treatment and control of animal diseases. A total of almost half a million samples weretested comprising more than a million tests to help the Department of Veterinary Services control and eradicate economically important diseases to safeguard the animal population. Of these, zoonotic diseases comprise a small but significant entity which needs careful attention (Chandrawathani et al., 2017) Dora Tan (1981) reported that among the many zoonotic diseases prevalent in Malaysia, are leptospirosis, rabies, influenza, Japanese encephalitis, toxoplasmosis,ornithosis, Q fever and monkeypox which have been investigated at the lnstitute for Medical Research, Kuala Lumpur. The regional laboratories have full capability to conduct tests to confirm parasitic, viral and bacterial infections except for rabies andavian influenza, which was diagnosed in the Veterinary Research Institute. However, preliminary tests for avian influenza wascarried out in regional laboratories.
Afficher plus [+] Moins [-]Comparison of methods for estimation of Toxoplasma gondii-specific antibody production in the aqueous humor of cats
1995
Hill, S.L. | Lappin, M.R. | Carman, J.
Intraocular production of Toxoplasma gondii-specific antibody in cats has been estimated by comparing the ratio of T gondii-specific antibody in aqueous humor and serum with the ratio of total immunoglobulins in serum and aqueous humor (Goldmann-Witmer coefficient; aqueous antibody coefficient; C value). It has been proposed that in human beings, comparison of the ratio of T gondii-specific antibody in aqueous humor and serum with the ratio of antibodies against a nonocular pathogen in serum and aqueous humor is more accurate than methods using total immunoglobulin quantification. We developed an ELISA for detection of calicivirus-specific antibodies in the serum and aqueous humor of cats. By evaluating calicivirus-specific antibody concentrations in the aqueous humor of healthy and diseased cats, calicivirus was assessed as a nonintraocular pathogen. The ratio of T gondii-specific antibodies in the aqueous humor and serum and the ratio of calicivirus-specific antibodies in serum and aqueous humor were evaluated as a means of estimating intraocular T gondii-specific antibody production. A field strain of feline calicivirus was isolated, cultured, and purified. A calicivirus-specific IgG ELISA was developed for detection of feline calicivirus-specific IgG in serum and aqueous humor. Calicivirus-specific IgG was measured in the serum and aqueous humor from 3 groups of control cats. Results suggested that calicivirus is a nonintraocular pathogen in cats and that calicivirus IgG detected in aqueous humor is attributable to leakage across a damaged blood-ocular barrier. Intraocular production of T gondii-specific antibodies was estimated, using 2 formulas. The C value was calculated by multiplying the ratio of T gondii-specific IgM or IgG in aqueous humor and serum by the ratio of total immunoglobulins (using the corresponding IgM or IgG class) in serum and aqueous humor. The Ctc value (Toxoplasma-calicivirus Goldmann-Witmer coefficient) was calculated by multiplying the ratio of T gondii-specific IgM or IgG in aqueous humor and serum by the ratio of calicivirus-specific IgG in serum and aqueous humor. Serum and aqueous humor samples were obtained from 41 client-owned cats with uveitis, and T gondii-specific C values and Ctc values were calculated. Toxoplasma gondii-specific IgM or IgG C values of 10 or greater or T gondii-specific IgM or IgG Ctc values of 1 or greater were considered to be suggestive of intraocular T gondii-specific antibody production. Of the 41 cats, 20 (48.7%) had evidence of intraocular production of T gondii-specific antibody on the basis of either an IgM or IgG C value of 10 or greater. A Ctc value could not be calculated in 3 cats because calicivirus-specific IgG was not present in aqueous humor. Of the 38 cats for which Ctc values could be calculated, 25 (65.8%) had evidence of intraocular production of T gondii-specific antibody on the basis of either an IgM or IgG Ctc value of 1 or greater. The C values and Ctc values were in agreement for 75.9% of IgM containing samples and 75% of IgG containing samples. Sensitivity, specificity, predictive value of a positive test result, and predictive value of a negative test result for an IgM or IgG C value, when compared with the corresponding IgM or IgG Ctc value were determined. The results indicate that use of the C value for estimation of intraocular T gondii-specific antibody production will result in 28.6 (IgM) to 50% IgG) false-negative results and 12.5% (IgM and IgG) false-positive results, when compared with the Ctc value.
Afficher plus [+] Moins [-]Detection of Toxoplasma gondii-specific IgA in the aqueous humor of cats
1995
Toxoplasma gondii-specific IgA, IgM, and IgG were measured by ELISA in the serum and aqueous humor of 29 client-owned cats with indigenous aviates and 7 specific-pathogen-free cats tested sequentially for 20 weeks after inoculation with T. gondii. Local antibody production in aqueous humor was estimated by multiplying the aqueous humor-to-serum T gondii-specific antibody ratio by the serum-to-aqueous humor total IgG (C value) or IgG (C value) ratio. Evidence for local production of antibody in aqueous humor was defined as C value greater than 8 or CTC value greater than 1. Toxoplasma gondii-specific IgM CTC values, IgG CTC values, or IgA CTC values greater than 1 were detected in the aqueous humor of 18 of 29 (62.1%) client-owned cats with endogenous uveitis; 2 cats had IgA CTC values greater than 1 without detectable IgM or IgG in aqueous humor. Toxoplasma gondii-specific IgM was not detected in the aqueous humor of experimentally inoculated cats before or after inoculation. Immunoglobulin G C values greater than 8 were detected in all 7 experimentally inoculated cats and ranged from 10.4 to 145.5. Immunoglobulin G C values greater than 8 were first detected 4 to 8 weeks after T gondii inoculation and were undetectable by week 16 after inoculation. Immunoglobulin A C values greater than 8 were detected in 4 of 7 cats and ranged from 12.7 to 264.3. Immunoglobulin A C values greater than 8 were first detected 4 to 8 weeks after inoculation, and were detected in 2 cats during week 20 after inoculation. It was concluded that some cats infected with T gondii develop detectable concentrations of T gondii-specific IgA in aqueous humor.
Afficher plus [+] Moins [-]Persistence of immunity to toxoplasmosis in pigs vaccinated with a nonpersistent strain of Toxoplasma gondii
1994
Dubey, J.P. | Baker, D.G. | Davis, S.W. | Urban, J.F. Jr | Shen, S.K.
Persistence of the vaccine RH strain of Toxoplasma gondii was studied by bioassay and histologically in 14 pigs. Pigs were euthanatized 2, 4, 7, 8, 14, 15, 21, 29, 36, 42, 52, 57, and 76 days after IM inoculation with 100,000 T gondii tachyzoites. Viable T gondii tachyzoites derived from the RH strain were isolated by bioassay in mice inoculated with tissues of pigs euthanatized up to 14 days after vaccination. Except for fever, pigs vaccinated IM with the RH strain remained clinically normal. Two other pigs inoculated IV with 100,000 T gondii tachyzoites of the RH strain became ill, and 1 pig was comatose by 4 days after inoculation. These findings indicate that route of inoculation may influence the response of pigs to T gondii. To evaluate protective immunity in pigs vaccinated with the RH strain, 16 age-matched pigs were allotted to 4 groups (A-D) of 4 pigs each. Eight pigs (groups A and C) were vaccinated IM with 100,000 RH strain tachyzoites and 8 pigs (groups B and D) were nonvaccinated controls. Pigs of groups A and C were challenge-inoculated orally with a lethal dose of T gondii oocysts (100,000 oocysts) 81 days after vaccination, pigs of groups B and D were inoculated similarly 220 days after vaccination. The concentration of T gondii at 3 days after challenge inoculation of pigs vaccinated 81 days earlier was reduced 100,000-fold in mesenteric lymph nodes, compared with that in a nonvaccinated pig euthanatized at 3 days after challenge inoculation. Another nonvaccinated pig became comatose and had to be euthanatized at 7 days after challenge inoculation, numerous tachyzoites were in its mesenteric lymph nodes, intestines, and liver. The vaccinated pigs generally remained clinically after challenge inoculation with oocysts. Toxoplasma gondii was not isolated by bioassays from tissues of 5 of 8 vaccinated pigs, but was recovered from all nonvaccinated pigs. Results indicate that protective immunity persisted in pigs for at least 7 months after vaccination with the nonpersistent RH strain of T gondii.
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