Experimental infection of Toxoplasma gondii in specific pathogen-free and commercial broiler chicks

Xiao Chen; Junpeng Chen; Qianqian Tan; Jinxuan Li; Xiaomei Liu; Qianqian Xiao; Hongmei Li; Xiaomin Zhao; Xiao Zhang

doi:10.1016/j.cimid.2022.101890

Experimental infection of Toxoplasma gondii in specific pathogen-free and commercial broiler chicks

Comp Immunol Microbiol Infect Dis. 2022 Nov-Dec:90-91:101890. doi: 10.1016/j.cimid.2022.101890. Epub 2022 Oct 1.

Authors

Xiao Chen¹, Junpeng Chen¹, Qianqian Tan¹, Jinxuan Li¹, Xiaomei Liu¹, Qianqian Xiao¹, Hongmei Li², Xiaomin Zhao², Xiao Zhang³

Affiliations

¹ Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Shandong Agricultural University, Tai'an, China.
² Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Shandong Agricultural University, Tai'an, China; Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Tai'an, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Tai'an, China.
³ Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Shandong Agricultural University, Tai'an, China; Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Tai'an, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Tai'an, China. Electronic address: tzhangxiao@126.com.

PMID: 36215765
DOI: 10.1016/j.cimid.2022.101890

Abstract

Toxoplasma gondii is an intracellular protozoan parasite that infects most warm-blooded animals, including humans, and causes toxoplasmosis. In this study, the pathogenicity of RH strain of T. gondii in broiler chicks was investigated and the susceptible tissues of chicks were clarified. Fourteen-day-old broiler chicks were injected intraperitoneally with 1 × 10⁷, 1 × 10⁶, and 1 × 10⁵ tachyzoites of T. gondii, respectively. The results showed that the spleen and lungs were frequently positive for T. gondii DNA. Moreover, in chicks, infection with only 1 × 10⁷ tachyzoites resulted in clinical symptoms, with lower weight gain, higher body temperature, anorexia and apathy, indicating that chicks are insusceptible to T. gondii infection. Then, this study investigated the relationship between T. gondii survival and chick body temperature. In the experiment, the invasion and proliferation of T. gondii were evaluated at 37 °C and 41 °C, respectively, and the survival of the parasites was significantly inhibited at 41 °C. In conclusion, broiler chicks are insusceptible to T. gondii infection, and the higher body temperature compared to other susceptible animals is a key factor in the reduction of T. gondii pathogenicity.

Keywords: Chicks; Infection; Susceptibility; Toxoplasma gondii.

MeSH terms

Animals
Chickens
Humans
Specific Pathogen-Free Organisms
Spleen / parasitology
Toxoplasma* / genetics
Toxoplasmosis* / parasitology