Determinação do número de gerações anuais e do período de desenvolvimento das formas imaturas de Haematobia irritans (Diptera: Muscidae) em massas fecais de bovinos Sindi no Semiárido Paraibano.

Abstract

Among the problems that affect bovine culture are the parasitic infestations caused by the horn fly, Haematobia irritans. The bite of this hematophagous insect causes stress to the animal, decreased the production of meat and or milk and the quality of the skin. Due to the importance of the parasite for Brazilian cattle breeding as a cause of great economic and productive losses, this dissertation, composed of two chapters, discusses a literature review about the horn-fly in Brazil and a scientific article on the population dynamics of the nonphase parasite of the fly in the semi-arid Paraiba. The first chapter aimed to characterize the epidemiology, susceptibility and control of the horn-fly in Brazilian livestock. A search was made in the Scielo, Lilacs, dissertations and theses of the official universities' websites with the terms "ectoparasites" and "damages caused", "H. irritans "," susceptibility "," control "and" epidemiology ", restricted to studies in Brazil. It was observed the necessity of studies on the dynamics of the parasite in the animal and fecal masses (MFs). In addition, MDC's resistance to conventional insecticides used in the market is a problem that affects parasite control. In the second chapter, the objective was to determine the number of annual generations and the period of development of the horn-fly in cattle in the semi-arid region of Paraíba. The experiment was carried out with the Sindi cattle MFs (kept without antiparasitic treatment) from the Research Nucleus for the Semi-Arid Tropic (NUPEÁRIDO) of the Federal University of Campina Grande (UFCG) Patos campus. During the period from July 2016 to July 2017, 620 MFs were collected and placed in emergency traps. The development period of H. irritans in MFs occurred from day 7 to day 11, a total of 11.390 MDC samples were collected and the sex ratio was 0.9: 1 between males and females, respectively. It can be concluded that the short period of development of H. irritans in bovine MFs determined the occurrence of 30 annual generations in the Paraíba semi-arid region. The climatic factors of temperature and rainfall are important for the emergence of MDC throughout the year, however, the frequency of rainfall decreases the emergence of the parasite. Control strategies should be tackled in order to reduce the economic losses caused by the horn-fly from the knowledge about its dynamics in the semi-arid.