This study was conducted to investigate the 
prevalence of blood protozoa infecting cattle, beside an invitro study of the efficacy of some common used acaricides i.e
(Chlorprifos, Deltamethrin and Ivermectin) against 
Rhipicephalus annulatus tick. Blood and tick samples were 
collected from 240 cattle, in addition to hemolymph smears 
from ticks were examined microscopically by using Giemsa's 
stained blood smear method. The study revealed that the 
overall prevalence of blood protozoa was 52%. Theileria
infection was the highest with rate of 44.58%, while, Babesia
infection was 2.5%, and Anaplasma infection was 2.9%. 
Blood protozoa infection was lower in young cattle, with 
41.67% in calves and 55.2% in adult cattle. Blood protozoa 
infection was higher in females (54.8%) than males (49.5%), 
however the mixed infection was found to be higher in males. 
Theileria spp. infection was the greatest among tick-borne 
parasites. The autumn season had the highest infection rate 
(21%), while the spring season had the lowest prevalence 
(15%). The highest tick's infestation rate was recorded in 
December (30%), and the lowest was in March (5%). The tick 
microscopically identified indicates only the presence of 
Rhipicephalus annulatus ticks. The microscopic examination 
of tick hemolymph revealed the presence of piroplasmic 
developmental stages in 37.2% of examined tick samples. The 
in-vitro results showed that chlorprifos had the highest 
efficacy of the tested acaricides, but deltamethrin and 
ivermectin demonstrated low efficacy. In conclusion, blood 
protozoa are still a threat on cattle in the study area and high 
restriction in using of deltamethrin and ivermectin is 
recommended due to low efficacy.