<i>Theileria annulata</i> seroprevalence among different cattle breeds in Rajshahi Division, Bangladesh

Abstract

An epidemiological survey of Theileria annulata infection was undertaken in a cattle population in Rajshahi Division, Bangladesh. The local cattle breeds from the area (North Bengal Gray and Deshi) and crosses between the local breeds and Holstein cattle were predominantly screened. In total, 192 cattle serum samples were collected in two areas of Rajshahi Division, the Rajshahi District (n=147) and Natore District (n=45). The samples were screened with an enzyme-linked immunosorbent assay using T. annulata surface protein (TaSP) as the antigen. The seroprevalence was 80.0% (36/45) in Natore and 20.4% (30/147) in Rajshahi. A logistic regression analysis showed that the sampling location was significantly associated with seropositivity, whereas age, sex and breed were not. Although the logistic regression analysis did not show a linear dependence on age, we considered age-specific seroprevalence separately in the two districts. Seroprevalence did not differ significantly among age categories in the Natore District. In contrast, all the cattle <1 year old in the Rajshahi District were seronegative (11/11). Seroprevalence in the 1- and 2-year-old cattle was significantly lower in the Rajshahi District than in the Natore District. In the older age categories (3, 4 and >5 years), seroprevalence did not differ significantly between the Natore and Rajshahi Districts. These results suggest that the cattle in the Rajshahi District were sporadically exposed to T. annulata, whereas most cattle in the Natore District became infected during an early phase of life.

Molecular detection of Babesia and Theileria from crossbred cattle in Sirajganj and Rangpur districts of Bangladesh

“…Limited studies also have performed serological examination to confirm the tentative diagnosis of infections (Ali et al, 2016;Rahman, Sumon et al, 2015). However, these studies are only reliable for the diagnosis of acute cases but have limited value in subclinical cases due to low parasitaemia (Alim et al, 2012;Hosen et al, 2020;Samad et al, 1983).…”

“…Several researchers identified bovine piroplasms using microscopic examination for epidemiological investigation (Al Mahmud et al., 2015 ; Chowdhury, Hossain et al., 2006 ). Limited studies also have performed serological examination to confirm the tentative diagnosis of infections (Ali et al., 2016 ; Rahman, Sumon et al., 2015 ). However, these studies are only reliable for the diagnosis of acute cases but have limited value in subclinical cases due to low parasitaemia (Alim et al., 2012 ; Hosen et al., 2020 ; Samad et al., 1983 ).…”

First Molecular detection of <i>Theileria annulata</i> in Bangladesh

“…In Bangladesh, it has been reported that approximately 22% of asymptomatic cattle showed seropositive for T. annulata [15]. We also recently reported that approximately 80 and 20% of asymptomatic cattle in Natore and Rajshahi district, Bangladesh, showed seropositive for T. annulata [1]. These reports suggested that asymptomatic infection of T. annulata is common among Bangladesh cattle.…”

“…To determine whether T. annulata infected cattle exists in Bangladesh, blood samples of fifty-nine asymptomatic cattle, 10 local breeding and 49 mix breeding, were randomely collected from a village in Singra Upazila (a subunit of a district) in the Natore District, Rajshahi Division of Bangladesh from February to April, 2017. There, farmers graze a few dozen local breeding and mix cattle in one place, and we recently reported that some cattle in the village have antibodies reacting with T. annulata surface protein [1]. However, it has not yet confirmed whether these cattle harbor the parasite.…”

“…Seroepidemiological surveys had suggested that asymptomatic infection of T. annulata is common, and it might be an infectious source to other host animals in Bangladesh [1]. However, existence of T. annulata in asymptomatic cattle had not been proven yet.…”