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This article presents the clinical and laboratorial findings in an outbreak of abortions and high neonatal mortality attributable to Trypanosoma evansi infection in camels. A total of 16 females were diagnosed, 2 of which showed moderate signs of chronic form, particularly hyporexia and intolerance to exercise. The main laboratorial findings were regenerative anemia (hemolytic anemia), lymphocytic and monocytic leukocytosis, hyperproteinemia, hyperglobulinemia, hypoglycemia, serum urea increased, and serum iron decreased. The most characteristic finding in the examined females would be the uremia, probably due to the higher protein metabolism.

Toxicity and therapeutic trials using Cymelarsan (an arsenical compound) against Trypanosoma evansi infection were carried out using chronically infected goats. For the toxicity trial, 40 goats were divided into four groups of 10 animals each; the first three groups received s.c. injections of 5, 10, and 15 mg/kg bw of Cymelarsan, respectively, and the last one served as control. No systemic reaction was observed in any goat throughout the experiment. For the therapeutic trial, 15 adult female goats were inoculated intravenously with at least 1 x 10(5)T. evansi isolated in the Canary Islands. Six months after inoculation, the animals were treated with Cymelarsan at single dose of 0.3 mg/kg (5 animals), 0.5 mg/kg (5 animals), and 0.625 mg/kg (5 animals). At 4 and 6 weeks after treatment, two goats belonging to 0.3 mg/kg group showed recurrence of trypanosomes. Parasitemia, however, was negative in all animals belonging to 0.5 and 0.625 mg/kg groups until the end of the experiment (6 months after treatment). Thus, it can be concluded that Cymelarsan is a safe trypanocidal drug for goats and that the curative dose is 0.5 mg/kg or above.

Trypanosoma theileri (Laveran, 1902) has been diagnosed in many countries and is commonly considered as a nonpathogenic hemoparasite, although some authors have described clinical signs in cattle infected with T. theileri. In April and May, 2005, 12 blood samples were received at the Exopol Diagnostic Laboratory (Zaragoza, Spain) from a Spanish bull-fighting farm located at Seville province. Clinical exploration of the animals revealed fever, progressive weight loss, anemia, and frequent recumbent position. Microscopic examination showed Theileria spp. in all cases (12), and in four of them, T. theileri was also observed. The clinical picture observed in the animals could be compatible with T. theileria infection. However, the contribution of T. theileri to the clinical signs seen at least in four cases is unknown. Further studies are necessary to determine the pathogenicity of T. theileri in the different animal species. To our knowledge, this is the first isolation of T. theileri in Spain.

Trypanosomosis is a major constraint on ruminant livestock production in Africa, Asia, and South America. The principal host species affected varies geographically, but buffalo, cattle, camels, and horses are particularly sensitive. Natural infections with Trypanosoma congolense, T. vivax, T. brucei, and T. evansi have been described in goats. Trypanosomosis in goats produces acute, subacute, chronic, or subclinical forms, being T. vivax, T. congolense, and T. evansi, the most invasive trypanosomes for goats. However, the role of goats in the epidemiology of trypanosomosis is largely discussed and not well understood. Thus, it has commonly been assumed that trypanosomosis presents a subclinical course and that goats do not play an important role in the epidemiology of the disease. This can partially be due to parasitemia caused by trypanosomes which has been considered low in goats. However, this assumption is currently undergoing a critical reappraisal because of goats may also serve as a reservoir of trypanosome infection for other species, including the human beings in the case of T. brucei rhodesiense. The present article describes the current status of trypanosomosis in goats in Africa, Asia, and South America. Pathogenesis, clinical features, diagnosis, and treatment of the different trypanosomes are also described. The possible role in the epidemiology of the disease in the different areas is also discussed.

A cross-sectional study has been carried out in order to determine the prevalence of Trypanosoma evansi infection in susceptible hosts in the Punjab region (Pakistan). A total of 170 equines and 150 dromedary camels were examined. Five (3.3%) and 6 (4%) camels were positive at parasitological and serological examination, respectively. None of the equines tested positive at any method. These results seem to indicate that T. evansi infection has a relatively low prevalence in the Punjab region. However, efforts must be done in order to establish control measures in affected herds and avoid dissemination of the disease.