Anaplasma marginale is the most important agent regarding cattle anaplasmosis. The main clinical signs of this disease are hemolitic anemia, jaundice, dyspnea, tachycardia, fever, fatigue, lacrimation, salivation, frequent urination, anorexia, weight loss, abortion and death. Antimicrobial therapy is the main therapeutic protocol. The aim of this paper was to assess the efficacy of this therapy frequently used in field conditions. In order to do so, 48 crossbred zebu cattle presenting suggestive clinical signs of the disease were assessed. The animals were submitted to blood sample collection to perform a CBC and DNA extraction to confirm the presence of A. marginale by the polymerase chain reaction (PCR) test. The animals were divided into three experimental groups to perform the therapeutic protocols, using imidocarb dipropionate, enrofloxacin and oxytetracycline. Thirty-six animals (75%) presented positive reaction to PCR. The positive animals do not present significant differences in the CBC and WBC when compared to the negative ones. However, the serum protein levels were lower in positive animals (P<0.05). All the treatments were able to reduce the infection throughout the treatment (P<0.01). However, in time 1, enrofloxacin presented greater effectiveness in relation to the other ones (P<0.01). After the end of the treatment no protocol was able to totally eliminate the infection by A. marginale in cattle naturaly infected and handled on the field.
Anaplasma spp; bovine; PCR; therapy