A systematic review and meta-analysis of the prevalence of parasitic infections in equids in Ethiopia

Abstract

We performed this review to determine the weighted prevalence of equids parasitic infections in Ethiopia. Article searches on parasites of equids were conducted using PubMed, PubMed Central, Google Scholar, Science Direct, Web of Sciences, Scopus, AJOLs and Research Gate. A random effects model was used to estimate the weighted prevalence and to study heterogeneity. The primary searches generated, 3082 potential studies, of which 66 reports met the inclusion criteria and were included in the meta-analysis. There were 32 reports involving two or more equids species, eighteen on donkeys, and sixteen on horses. Moreover, fifty of the reports mentioned helminth infections in equids, thirteen on protozoans, and three on ectoparasites. The estimated weighted prevalence of parasitic infections in equids was 58.3% (95% CI 50.8-65.4%, I² = 99%). Helminths were the most prevalent parasites in equids, accounting for 77.1% (95% CI 71.4%, 82%, I² = 98.5%), followed by ectoparasites at 35.4% (95% CI 33.4-37.52%, I² = 88.2%) and haemoparasites (protozoans) at 10.84% (95% CI 6.6%, 17.3%, I² = 98.1%). Furthermore, with a prevalence of 82.3% (95% CI 75.9-87.3%, I² = 97.4%), donkeys were the most affected equids with helminth parasites. From the reports, we found forty-three species of helminth parasites affecting equids, including thirty-four nematode species (Strongylus, Cyathostomum, Coronocyclus, Cylicocyclus, Cylicostephanus, Trichostrongylus, Oesophagodontus, Strongyloides, Triodontophorus, Gyalocephalus, Poteriostomum, Dictyocaulus, Oxyuris, Habronema, Draschia, Parascaris, Setaria, and Probstmayria species), three trematodes (two Fasciola and one Gastrodiscus species), three cestodes (two Anoplocephala and one Anoplocephaloides species) and three botfly larvae (one Rhinoestrus and two Gasterophilus species). Trypanosoma species (T. congolense, T. vivax, T. brucei, T. equiperdum, and T. evansi), piroplasms (Theileria equi and Babesia caballi), and Eimeria species have also been reported to affect equids. Ticks (Amblyomma variegatum, A. gemma, Rhipicephalus decoloratus, R. evertisi evertisi, R. pulchellus, R. muhsame, R. sanguineus, Hyalomma rufipes, and Hy. truncatum) and lice (Bovicola equi and Haematopinus asini) were the ectoparasites recorded to affect equids. The risk of publication bias across studies was likely to be high due to differences in publication year and diagnostic techniques. In conclusion, parasitic infections of equids are common in Ethiopia and are caused by a variety of parasite species, putting the performance and well-being of these packing animals at risk. Therefore, more research is needed to identify infection risk factors and raise awareness of the consequences of parasitism in order to provide strategies to mitigate the problems in equids.

Supplementary information: The online version contains supplementary material available at 10.1007/s12639-023-01598-3.

Keywords: Equids; Ethiopia; Meta-analysis; Parasites; Prevalence; Systematic review.

Fig. 1

PRISMA flow chart describing the selection process (Moher et al. 2015)

Fig. 2

Distribution of studies performed on equids parasites in Ethiopia

Fig. 3

Trendline and equation depicting the growing trend of published articles over years

Fig. 4

Forest plot of the logit event rate (lp) of parasitic infections in equids in Ethiopia

Fig. 5

Galbraith plot for the prevalence of parasitic infections in equids in Ethiopia

Fig. 6

Funnel plot with 95% confidence limits of the prevalence of parasitic infections in equids in Ethiopia

Fig. 7

Egger’s publication bias plot (A) and Begg’s funnel plot (B) reports on equids parasites

Fig. 8

Pooled prevalence of parasitic infections of equids by geographic locations