| dc.description.abstract | Among the global agricultural sectors, livestock production is one of the most developed and dynamic. Breeding and domestication of livestock for food production is an enterprise that promotes economic stability at a global level. However, the southern cattle fever tick (SCFT) a.k.a the tropical cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini), causes large economic losses in cattle production, particularly in tropical and subtropical parts of the world. In the United States losses were estimated to be ~$130.5 million in the late 1800’s before the eradication program began. Ectoparasites develop easily and abundantly in tropics and subtropics and are responsible for large economic losses in the dairy and meat industry through weight loss, hide damage, and death from anemia. The southern cattle tick R. microplus is a one-host tick species considered the most important ectoparasite of livestock in the world because of its association with high financial loss due to direct feeding (tick burden) and in the transmission of the hemoparasites Babesia bovis, B. bigemina, and Anaplasma marginale, the causative agents of babesiosis and anaplasmosis, respectively. Rhipicephalus microplus has a high potential for population growth due to its relatively short life cycle and preference for cattle, reared in large numbers throughout the tropics and subtropics. Unfortunately, ticks in many parts of the world have evolved resistance to all pesticides available on the market, driving the development of new technologies to control this species. Vaccination against ticks using the gut protein Bm86 has been shown to be effective against acaricide-resistant ticks. This technique has been successfully implemented in Puerto Rico for the control of R. microplus on dairy and beef cattle. Observations from Puerto Rico indicate a potential interaction between anti-tick vaccination in conjunction with systemic acaricide use. Controlled animal studies were completed directly comparing efficacy of vaccination with and without systemic acaricide. Additionally, in vitro feeding of ticks with immunoglobulin-G (IgG) from vaccinated animals with several combinations of acaridides was used to screen antigen/acaricide combinations and to confirm results of field tests using animals. The results show that the vaccine had a synergistic interaction with the acaricide. Better and longer control was achieved with the combination than when either treatment was applied alone. | |
