Molecular detection and genotype identification of Toxoplasma gondii in domestic and industrial eggs

Abstract

Birds are important intermediated hosts of Toxoplasma gondii. Consumption of chicken meat and its infected products is one of the main sources of human infection with T. gondii. However, little information is available about T. gondii infection in egg. In this study, the contamination of industrial and local eggs with Toxoplasma was investigated by PCR method targeting the RE gene in two tropical cities of Iran. Genotypes of T. gondii were determined by PCR‐RFLP method targeting the SAG3 gene. T. gondii DNA was detected in 11% (22/200) of the eggs. Genotyping of 14 T. gondii isolates revealed that all of the isolates were belonged to genotype III of T. gondii. Sequencing of the isolates by the SAG3 gene showed 95%–100% similarity with the T. gondii isolates in GenBank. Practical applications The findings of this study suggested that consumption of raw or undercooked eggs might play a role in human infection with Toxoplasma. Hence, consumption of adequately cooked eggs should be considered for prevention of human toxoplasmosis.

Toxoplasma gondii in Slaughtered Sheep in High- and Low-Humidity Regions in the South of Iran: Molecular Prevalence and Genotype Identification

“…Our previous study on T. gondii infection in eggs carried out in the Hajiabad region showed no contamination. e facts indicate that humidity plays an important role in the spread of toxoplasmosis [18].…”

“…Our previous study on T. gondii infection in eggs carried out in the Hajiabad region showed no contamination. The facts indicate that humidity plays an important role in the spread of toxoplasmosis [ 18 ]. Genotyping of 57 isolates obtained from sheep in the USA resulted in 45.6 percent of type II, 15.7 per cent of type III, and 22 atypical isolates [ 27 ].…”

“…No. A170301), MgCl 2 , 2 mM, primers 2 μ L (pmol 10), DNA 2 μ L, and water [ 18 ]. The PCR reaction was carried out with an initial denaturation temperature of 94°C (30 sec), 35 cycles of 94°C (30 sec), annealing of 56°C (30 sec), and extension of 72°C (30 sec) followed by the final extension at 72°C (10 min).…”

“…To prevent evaporation, the material was completely covered with parafilm, and then, the tubes were placed in a bain marie at 65°C for 4 hours. The PCR product was then resolved on 3 percent agarose gel in TAE buffer [ 18 , 19 ]. To obtain the RFLP pattern of the GRA6 gene, sequences of three known types of RH type I, ME49 type II, and NED type III parasites were obtained from GenBank and enzyme online at nebcutter ( http://nc2.neb.com/NEBcutter2 ) [ 19 ].…”

“…To prevent evaporation, the material was completely covered with parafilm, and then, the tubes were placed in a bain marie at 37°C for 10 hours. The PCR product was then resolved on 3 percent agarose gel in TAE buffer [ 18 , 19 ].…”