Bovine piroplasmosis-anaplasmosis and clinical signs of tropical theileriosis in the plains of Djurdjura (north Algeria)

The study was conducted during tick activity season over a period of 5 years in the Djurdjura Plains, Algeria. A total of 299 cattle (Holstein, Montbeliard, Fleckvieh and crossbred animals) with clinical signs were included in this study. A total of 171 animals were found positive for at least one pathogen by Giemsa-stained blood smears examinationTheileria annulata(136/299, 45.5%),Babesia bovis(14/299, 4.7%),B. bigemina(3/299, 1.0%) andAnaplasma marginale(12/299, 4.0%) were identified. Six animals were co-infected byT. annulataandA. marginale. Although no ticks were collected from diseased animals, clinical signs in cattle were hyperthermia (120/136, 88.3%), gluttony followed by anorexia (113/136, 83.1%), lymph node enlargement (99/136, 72.8%), anaemia (82/136, 60.3%), icterus (58/136, 42.6%) and haemoglobinuria (36/136, 26.5%). Gluttony followed by anorexia was considered highly suggestive of an incubation of tropical theileriosis as shown by a higher receptivity index (IR = 0.89-1). This clinical sign is evident in young Montbeliard and young Holstein males with anaemia (IR = 1) and icterus (IR = 0.78-0.81) which is earlier than haemoglobinuria (IR = 0.51-0.54). The incidence ofT. annulatawas maximum in July (n = 57), as well asB. bovis(n = 6) andA. marginale(n = 13). These results highlight the preponderance of tropical theileriosis in north-central Algeria, where gluttony followed by anorexia is probably a prodromal symptom during the incubation period of the disease.