PREVALENCE OF Blastocystis sp. IN CATTLE, GOAT AND SHEEP REARED BY DIFFERENT FARM MANAGEMENT SYSTEMS IN PAHANG, MALAYSIA

Epidemiology of Blastocystis in farm animals: A review

Blastocystis is a ubiquitous gastrointestinal protozoan parasite found both in humans and animals. The purpose of this review is to look at the prevalence and genetic diversity of Blastocystis in farm animals, including cattle, sheep, goats, pigs, and poultry, and discuss the potential evidence of transmission between animals and humans, as well as highlight the related risk factors and public health significance. Significant differences have been found in the prevalence of Blastocystis in different hosts worldwide. The global prevalence of Blastocystis infection was 13.6 % in cattle (1219/8961), 15.9 % in sheep (675/4233), 31.7 % in goats (837/2640), 44.57 % in pigs (2589/5808), and 26.29 % in poultry (892/3392). Blastocystis is mainly transmitted through fecal-oral routes. The existence of the same subtypes of the parasite in both animals and humans indicates potential zoonotic transmission. Subtypes ST10 (43.39 %) and ST14 (19.99 %) were most frequently found in cattle, sheep, and goats, while ST5 (62.57 %) was predominantly observed in pigs, and ST6 (16 %) and ST7 (36.6 %) were commonly recorded in poultry. Analysis of risk factors suggests that age, sex, close contact with animals, geographical location, farm management system, and season were the significant risk factors reported in many studies. Although epidemiology and subtype distribution of Blastocystis in different hosts have been described in several studies, understanding the possible transmission pathway from farm animals to humans and the public health impacts of Blastocystis requires more extensive studies.

Prevalence, potential risk factors and genetic diversity of Blastocystis in ruminant livestock animals from Penang, Malaysia

Blastocystis is a unicellular, anaerobic protist inhabiting the intestinal tract of diverse animal hosts, including human. Information regarding Blastocystis in small ruminants, namely goats and sheep, is limited globally; thus, this study was carried out to investigate the distribution and determinants of Blastocystis in ruminant livestock animals from Penang, Malaysia. Fecal samples from 127 cattle, 149 goats, and 100 sheep were examined for Blastocystis by in vitro cultivation using modified Jones' medium, while DNA barcoding was used for subtyping. Overall, 23.1% (87/376) of animals screened were positive for Blastocystis sp. The prevalence of infection was significantly higher in goats than in cattle and sheep, while the female gender, semi-intensive farming system, and the Northeast Penang Island district were identified as potential risk factors for Blastocystis infection. Blastocystis sp. ST5, ST14, and ST25 were identified in cattle; ST5, ST10, ST13, and ST14 in goats; and ST4, ST5, ST14, and ST15 in sheep. ST5 and ST14 were found to be the most abundant and widespread subtypes in the study area. To the best of our knowledge, this is the first report of ST4 from sheep and ST13 from goats, thus serving as an update to the host range of Blastocystis sp. ST4 and ST13. The isolation of ST4 and ST5 in this study suggests that ruminant livestock animals could serve as reservoirs of human infection.