Prevalence, Associated Risk Factors, and Phylogenetic Analysis of Toxocara vitulorum Infection in Yaks on the Qinghai Tibetan Plateau, China

Abstract

Toxocara vitulorum has been rarely reported in yaks at high altitudes and remote areas of Sichuan Province of Tibetan Plateau of China. The current study was designed to investigate the prevalence, associated risk factors, and phylogenetic characteristics of T. vitulorum in yak calves on the Qinghai Tibetan plateau. Fecal samples were collected from 891 yak calves and were examined for the presence of T. vitulorum eggs by the McMaster technique. A multivariable logistic regression model was employed to explore variables potentially associated with exposure to T. vitulorum infection. T. vitulorum specimens were collected from the feces of yaks in Hongyuan of Sichuan Province, China. DNA was extracted from ascaris. After PCR amplification, the sequencing of ND1 gene was carried out and phylogenetic analyses was performed by MEGA 6.0 software. The results showed that 64 (20.1%; 95% CI 15.8–24.9%), 75 (17.2; 13.8–21.1), 29 (40.9; 29.3–53.2), and 5 (7.6; 2.5–16.8) yak calves were detected out to excrete T. vitulorum eggs in yak calve feces in Qinghai, Tibet, Sichuan, and Gansu, respectively. The present study revealed that high infection and mortality by T. vitulorum is wildly spread on the Qinghai Tibetan plateau, China by fecal examination. Geographical origin, ages, and fecal consistencies are the risk factors associated with T. vitulorum prevalence by logistic regression analysis. Molecular detection and phylogenetic analysis of ND1 gene of T. vitulorum indicated that T. vitulorum in the yak calves on the Qinghai Tibetan plateau are homologous to preveiously studies reported.

Genetic Characterization of Toxocara vitilorum in Turkey by Mitochondrial Gene Markers (cox1)

“…Even though T. vitulorum is one of the least discussed parasites on the determination of helminthic fauna of domestic animals in Turkey, previous epidemiological studies have indicated that infection rate is 0.3-29.0%. This prevalence rate recorded in Turkey ruminants is not negligible compared with the rate of prevalence rates recorded in other countries [1,9].…”

“…The genetic analysis of parasites is a crucial factor in terms of determining epidemiology and the control parasitic diseases of humans and animals [9]. Toxocara vitulorum is the most common gastrointestinal helmints infecting ruminants particularly in tropical regions [18].…”

“…using polymerase chain reaction (PCR)-based techniques [16]. Li et al [9] showed that for the ND1 gene, T. vitulorum was homologous to T. vitulorum ( no. AJ937266) as previously reported by the same authors [10].…”

Besnoitiosis: An Emerging Parasitic Disease in Yaks (Bos grunniens) and Tibetan Sheep (Ovies aries) on the Qinghai Tibetan Plateau, China

“…With growing economic and social reforms in China, the meat products demands especially of beef and mutton types have increased during the last decade (Li et al, 2016;Li et al, 2017). According to census 2016, about 106 and 16 million heads of cattle and sheep respectively have been counted in China (National Bureau of Statistics of China: http://data.stats.gov.cn/easyquery.htm?cn=C01).…”

A Report on the Multivariable Sites of the Mitochondrial Genome of a Bamboo Rat, Rhizomys pruinosus from Wenzhou, China

“…The mitochondrial (mt) DNA have been widely utilized as molecular markers in the study of taxonomy, population genetics, phylogenetic and evolutionary analyses due to its maternal inheritance (Li et al, 2008(Li et al, , 2016a(Li et al, , b, 2017aYan et al, 2018). The mt DNA was reported to have a higher mutation rate than that of nuclear DNA (Zhao et al, 2014) and it was reported to be highly related to various diseases due to the alteration of mt DNA content (Zong et al, 2016;Chen et al, 2016).…”