Natural infestation of Boophilus microplus Canestrini, 1887 (Acari: Ixodidae) in two cattle genotypes in the humid tropic of Veracruz, Mexico.

The aim of this study was to determine the annual dynamic population of Boophilus microplus in two cattle genotypes. The study was carried out in Martinez de la Torre, Veracruz, Mexico (tropical humid region). Twenty steers of 10 months of age, 185 kg of body weight and naturally infested with B. microplus ticks were used. Two groups of 10 animals were used according to their genotype (¾ Bos taurus [½ Holstein, ¼ Simmental, ¼ Zebu], and ½ Bos taurus [½ Holstein, ½ Zebu]). Animals grazed together in a pasture of five hectares. No ixodicidal treatment was used during the experiment. The number of B. microplus female ticks (> 4.5 mm length) was assessed every 28 days. Temperature (T), relative humidity (RH) and pluvial precipitation (PP) were registered during the study. The U Mann Whitney test was used to analyze differences between both animal genotypes (P < 0.05). Correlations between the number of B. microplus of both genotypes, PP accumulated and average of T (minimum and maximum) regis tered four weeks prior measurement were determined. Throughout the studied period, tick infestation in both animal genotypes was registered. The genotype ¾ Bos taurus had higher B. microplus infestation in nine of the 12 evaluated months (P < 0.05). PP accumulated and minimum T were correlated with the number of ticks in both genotypes. Natural infestation of Boophilus microplus Canestrini, 1887 (Acari: Ixodidae) in two cattle genotypes in the humid tropic of Veracruz, Mexico. [ABSTRACT FROM AUTHOR]