Submitted to: Annals of the New York Academy of Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/15/1997
Publication Date: N/A
Interpretive Summary: Morocco has a policy of importing improved dairy cattle to meet their growing need for dairy products. One source of improved breeds is the U.S. However, imported breeds are very susceptible to tick infestations and the diseases that they transmit. Among the diseases is babesiosis, caused by protozoa that reside in the red blood cells. While two species of Babesia (Babesia bovis and B. bigemina) are found in Moroccan cattle, there is no information on the extent of infections throughout the country, and as a consequence, there is inadequate information to assess the economic impact. Also, this disease is often confused with two other diseases, since there has not been good diagnostic tests available which can discriminate among the three diseases. Diagnostic assays developed in our laboratories were transferred to Morocco, and used to identify the prevalence of the disease in two regions of the country, where the most imported dairy cattle are found. The study confirmed the presence of both species, provided evidence that B. bovis is more prevalent than B. bigemina, and identified the most likely tick species involved in transmission. With this information, further tick transmission studies can be proposed, and a larger study to assess the distribution throughout the country developed.
Technical Abstract: A total of 475 bovine sera collected in 1995-1996 from 10 areas belonging to two different bioclimatic strata were tested for antibody activity to Babesia bigemina and Babesia bovis using the indirect fluorescent antibody test (IFAT). In the Gharb, the B. bovis seroprevalence was 21.7% and for B. bigemina, 10.8%. The infection rate for either or both species as determined microscopically with Giemsa-stained blood films was 18.9%. The Tiflet area was considered an endemic focus, and the seroprevalence was 42.2% for B. bovis and 40% for B. bigemina. The infection rate by stained blood film microscopy was 66.6%. In the Haouz region, only B. bovis was found, and the seroprevalence was 10.1% with 9.4% microscopically positive blood films. More than 80% of the cattle surveyed were infested by ticks and the mean infestation rate was 36 ticks per animal and 21 ticks per animal in the Gharb and Haouz, respectively. Six species were identified Hyalomma marginatum, Hyalomma detritum, Hyalomma anatolicum Rhipicephalus bursa, Rhipicephalus sanguineous and Boophilus annulatus. Boophilus annulatus was found in both regions with high prevalence in the Gharb (31.3%). No further correlation was made between the identified species as vectors and the presence of B. bovis and B. bigemina in these areas.