title: Prevalence of megabacteria in budgerigar colonies.
abstract: OBJECTIVE
  To measure the prevalence of megabacteria in budgerigar-breeding colonies and to evaluate possible methods to reduce the prevalence.
  
  
  METHODS
  A monitoring study over several years.
  
  
  METHODS
  Two budgerigar (Melopsittacus undulatus) colonies with over 300 birds each.
  
  
  METHODS
  The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
  
  
  RESULTS
  The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
  
  
  CONCLUSIONS
  The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled.
authors.affiliation: School of Veterinary Science, University of Queensland.
authors.forename: L J
authors.initials: LJ
authors.lastname: Filippich
authors.forename: J K
authors.initials: JK
authors.lastname: Hendrikz
mesh_terms: D000666:Amphotericin B / Q000627:therapeutic use; D000818:Animals; D000935:Antifungal Agents / Q000627:therapeutic use; D001715:Bird Diseases / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D015331:Cohort Studies; D005243:Feces / Q000382:microbiology*; D005260:Female; D005500:Follow-Up Studies; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy / Q000453:epidemiology / Q000662:veterinary*; D016987:Gram-Positive Rods / Q000302:isolation & purification*; D008297:Male; D010311:Parrots / Q000382:microbiology*; D015995:Prevalence
chemical_list: D000935:Antifungal Agents; D000666:Amphotericin B