Trematode infections in cattle in Arumeru District, Tanzania are associated with irrigation

Abstract

BackgroundThe relationship between the environment and infection of cattle with trematodes was studied at Arumeru District, Arusha Region, northern Tanzania. Randomly selected villages were grouped into three cattle management strata, (i) zero-grazing (ZZ) (ii) communal grazing without irrigation (ZC) and (iii) communal grazing with irrigation (ZCI).MethodsFaecal samples were collected from 241 cattle, and processed using the Flukefinder® method. Snail intermediate hosts were collected with a snail scoop from the water bodies in the study villages and identified morphologically.ResultsThe overall prevalence of F. gigantica, paramphistomes and S. bovis were 33%, 37% and 2% respectively. Prevalence for F. gigantica, paramphistomes, and S. bovis for each stratum were, zero-grazing (ZZ) (29.7%, 36.0% and 0%), communal grazing without irrigation (ZC) (6.3%, 15.0% and 3.8%) and communal grazing with irrigation (ZCI) (57.7%, 56.7% and 1.0%) respectively. The differences between strata were significant for F. gigantica (p < 0.001) and paramphistomes (p < 0.05) but not for S. bovis. Irrigation could account for the high prevalence of F. gigantica and paramphistomes in the ZCI stratum as compared to the ZZ and ZC strata. The higher prevalences of F. gigantica and paramphistomes in the ZZ stratum compared with the ZC stratum were unexpected and attributed to the practice of farmers in some ZZ stratum villages buying fodder for their cattle obtained from pastures in ZCI villages.ConclusionTrematode infections in cattle are prevalent in Arumeru District. Fasciola gigantica and paramphistomes are associated with grazing in areas with irrigation of crops. Zero-grazing of cattle does not necessarily prevent the risk of infection.

Helminths and Protozoa of the Gastrointestinal Tract of Ruminants in Tanzania

“…This seasonality is in agreement with other investigators who suggested that heavy mortality as a result of fasciolosis occurred during the dry season [49,51]. Cattle grazing in irrigation areas are most susceptible to infection [39].…”

“…Liver fluke transmission is dependent on the presence of its snail intermediate host so distribution of the parasite is limited to geographic areas where the appropriate snail species is present [39]. A high prevalence of fasciolosis has been shown towards the end of the dry season and the early part of the rainy season [21,41].…”

“…They cause significant economic losses due to reduction in production efficiency by 5 per cent in mild infestations to 10 per cent in more severe ones and in weight loss and abattoir condemnations [21,41,[43][44][45][46][47][48]. The most prevalent species in Tanzania are Fasciola gigantica and F. hepatica [35,39,41]. Several researchers using slaughterhouse surveys have studied the infection rates of trematodes in domestic animals [19,36,38,48].…”

A review of bovine fasciolosis and other trematode infections in Nigeria

“…Tropical fasciolosis due to F. gigantica Cobbold 1855 has been reported in several parts of Africa , Phiri et al, 2005a, Abebe et al,2010, Nzalawahe et al, 2014 and is likely to be a problem throughout the continent.…”

“…The convergence of cattle in common graze land during dry season as well as irrigation practices has been implicated in high prevalence of paramphistomosis (Nzalawahe et al, 2014). In a cross-sectional study in Ethiopia, 51.8% of cattle slaughtered were positive for paramphistomosis with peak prevalence rates observed during October to November (Ayalew et al, 2016).…”