Control of anaplasmosis and babesiosis in young cattle : a thesis /
| Main Author: | |
|---|---|
| Format: | Thesis Book |
| Language: | English |
| Published: |
[College Station, Tex.] :
[Texas A&M University],
[1972]
|
| Subjects: |
| Abstract: | ABSTRACT: A study was conducted on the control of anaplasmosis and babesiosis in young cattle in Colombia. Three groups of 10 calves were used at each of 3 different climatic and geographic areas. One group was vaccinated with an attenuated Anaplasma marginale vaccine and a killed Babesia bigemina, Babesia argentina vaccine. A second group was injected with infected Anaplasma marginale, Babesia bigemina and Babesia argentina blood that originated from donor cattle from the eastern plains. Five days post inoculation the induced infection was treated by injection of compounds 356C61 (alpha-ethoxyethylglyoxal dithiosemicarbazone) and 4A65 (3,3-Bis-(2-imidazolin-2-yl) carbanilide dihydrochloride). The third group of calves was used as a control. Calves selected for use at Monteria were not native to that area. All calves were subjected to natural exposure. Ticks were collected and identified at each site. There was no apparent significant difference in weight gains and resistance to anaplasmosis and babesiosis between groups at any site. At Bugalagrande and Girardot the absence of death losses from anaplasmosis and babesiosis in the control groups inidcates that the calves had a preexisting natural immunity, an acquired non-sterile immunity at the beginning of the study, or no challenge during the study. At Monteria, it is apparent that the vaccinated and premunized calves did not develop resistance to anaplasmosis and babesiosis due to the use of antigenically different organisms; the simultaneous injection of the premunization drugs at 5 days post inoculation; the lack of sufficient sterile immunity to suppress tick-borne infection; or the inability of the very young calves to develop sufficient resistance. The identification of Boophilus microplus ticks at all 3 sites confirms reports of this vector in anaplasmosis and babesiosis enzootic areas of Colombia. The significance of Anocentor nitens ticks on Anaplasma and Babesia spp. infected cattle is not apparent at this time. As a result of this study, it is concluded that the control of bovine anaplasmosis and babesiosis in tropical areas is more complex than previously recognized. More investigation is needed to obtain information on strain antigenicity of Anaplasma marginale, Babesia bigemina and Babesia argentina; mechanisms of coinfectious immunity; sterile immunity; and the action of chemical compounds tested in this study. |
|---|---|
| Item Description: | Vita. "Major Subject: Veterinary Microbiology". "Submitted to the Graduate College of the Texas A&M University partial fulfillment of the requirement for the degree of Master of Science December 1972". |
| Physical Description: | xi, 72 leaves : charts ; 28 cm |
| Bibliography: | Includes bibliographical references. |