half of the B. microplus and 6. annulatus larvae that hatch on 

 a given day will attach and feed on the host 



Knowledge of fundamental aspects of the genetics of 

 Boophilus Wcks are critical steps in development of genetic 

 control approaches. Tick isozymes serve as genetic markers 

 for research on these ticks and several recent investigations 

 have involved the analysis of enzyme characteristics. A 

 number of isozymes have been characterized and used as 

 genetic markers in an investigation of genetic similarity and 

 variability between natural populations of North American 

 Boophilus species. The results demonstrate a high degree of 

 similarity between populations of B. microplus irom Puerto 

 Rico, Mexico, and south Texas. These data indicate that 

 implementation of any genetic control method developed in 

 the future would not be limited by the occurrence of 

 genetically divergent populations of cattle fever ticks. 

 Additional genetic research has documented linkage 

 relationships among 12 enzyme loci in cattle fever ticks, and 

 cytogenetic investigations are using chromosome staining 

 techniques to elucidate details of the morphology of individual 

 chromosomes. These cytogenetic data will be useful in a 

 number of ways, including efforts to implement and improve 

 the sterile hybrid male Soop/7;7us technology. 



Proposed Model State Regulation for Control of Zoological 

 Animals 



The increased trade and interstate movement of zoological 

 animals in recent years resulted in problems in control and 

 dissemination of diseases and parasites in these animals. 

 Many diseases of zoological -type animals also affect common 

 domesticated food-type animals. Some of these economically 

 important diseases and parasites include tuberculosis, 

 brucellosis, exotic Newcastle disease, lethal avian influenza, 

 and exotic ticks. Zoological animals also may produce 

 environmental damage, crop destruction, and public safety 

 ahd health concerns, as well as creating situations where 

 there are violations of animal welfare laws. Because of the 

 concern of livestock industry and animal health officials, the 

 U.S. Animal Health Association requested that APHIS, USDA, 

 develop a model State Regulation for Control of Zoological 

 Animals. With the assistance of the Southeastern Wildlife 

 Disease Study, University of Georgia, APHIS is currently 

 developing the model regulation. The first draft was completed 

 in October 1986 and has been sent for comment to over 150 

 organizations, agencies, and individuals. This proposed 

 regulation is not intended to be passed into Federal law. It is to 

 serve as a model for the various States to use to draft laws 

 and regulations where a need exists. The revised draft of the 

 model regulation should be completed in early 1987 after 

 receiving input from the various interested parties involved 

 with zoological animals. 



