Molecular survey of pathogenic trypanosomes in naturally infected Nigerian cattle

• Published in: Research in veterinary science 2013-06, Vol.94 (3), p.555-561
• Main Authors: Takeet, Michael I., Fagbemi, Benjamin O., Donato, Marcos De, Yakubu, Abdulmojeed, Rodulfo, Hectorina E., Peters, Sunday O., Wheto, Matthew, Imumorin, Ikhide G.
• Format: Article
• Language: English
• Subjects: Age; Animals; Anticoagulants; Cattle; Cattle - parasitology; Coinfection - parasitology; Coinfection - veterinary; Female; hematocrit; Infections; Male; microscopy; mixed infection; Molecular diagnostics; Nigeria; Nigeria - epidemiology; Parasites; PCR; polymerase chain reaction; Polymerase Chain Reaction - veterinary; Prevalence; Sequence Analysis, DNA - veterinary; surveys; Trypanosoma - genetics; Trypanosoma brucei; Trypanosoma brucei brucei - genetics; Trypanosoma congolense; Trypanosoma congolense - genetics; Trypanosoma evansi; Trypanosoma vivax; Trypanosoma vivax - genetics; Trypanosomes; Trypanosomiasis, African - epidemiology; Trypanosomiasis, African - veterinary; Trypanosomiasis, Bovine - epidemiology; Trypanosomiasis, Bovine - parasitology; Veterinary medicine; White Fulani
• ISSN: 0034-5288; 1532-2661
• DOI: 10.1016/j.rvsc.2012.10.018

Microscopy and polymerase chain reaction (PCR) were used to survey pathogenic trypanosome infection in naturally infected Nigerian cattle. In 411 animals sampled, microscopy detected 15.1% positive infection of at least one of Trypanosoma brucei, Trypanosoma congolense or Trypanosoma vivax, while PCR detected 63.7% positive infections of at least one of those species and Trypanosoma evansi. PCR detected 4.4%, 48.7%, 26.0% and 0.5% respectively of T. brucei, T. congolense, T. vivax and T. evansi infections. All of the T. congolense detected were savannah-type, except for two forest-type infections. Prevalence of mixed infections was 13.9%, being primarily co-infection by T. congolense and T. vivax while prevalence of mixed infections by T. evansi, T. vivax and T. congolense was 1.5%. Microscopy showed poor sensitivity but specificity greater than 94%. Infection rates were much higher in Southern than in Northern Nigeria. Infections were lowest in N’dama compared to Muturu, Sokoto Gudali and White Fulani breeds. Animals with T. vivax monoinfection and mixed infections showed significantly lower packed cell volume (PCV) values. Those infected with any Trypanosoma species with 200 parasites/μl. The new finding of savannah- and forest- type T. congolense in Nigeria and the relatively high abundance of mixed infections are of significant clinical relevance. This study also suggests that T. congolense is the most prevalent species in Nigeria.