title: Flow cytometric analysis of nuclear DNA for sex identification in three psittacine species.
abstract: OBJECTIVE
  To evaluate flow cytometric analysis for sex identification in 3 psittacine species, establish reference values for blood cell DNA content for each species, and determine effects of sample storage on DNA content.
  
  
  METHODS
  36 orange-winged Amazon parrots, 41 budgerigars, and 39 cockatiels.
  
  
  METHODS
  Blood samples were stained and analyzed by use of flow cytometry to measure cellular DNA content. Samples were analyzed immediately after collection and after being stored at 4 C for 48 and 72 hours.
  
  
  RESULTS
  Mean DNA content (picograms per cell) was 3.248 for Amazon parrots, 2.702 for budgerigars, and 2.946 for cockatiels; DNA concentrations in samples analyzed immediately overlapped in a male and a female Amazon parrot and among 19 cockatiels. For budgerigars, DNA overlap between sexes was not detected in samples analyzed immediately or after storage for 72 hours. Sex was identified correctly in 94.4% of Amazon parrots, 100% of budgerigars, and 51.3% of cockatiels. For both sexes, DNA content in samples analyzed immediately was significantly different from that of stored samples.
  
  
  CONCLUSIONS
  Flow cytometric analysis was accurate for sex identification of Amazon parrots and budgerigars. Sample storage at 4 C for 48 or 72 hours caused variability in DNA content.
authors.affiliation: Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis 95616, USA.
authors.forename: N R
authors.initials: NR
authors.lastname: Canon
authors.forename: L A
authors.initials: LA
authors.lastname: Tell
authors.forename: M L
authors.initials: ML
authors.lastname: Needham
authors.forename: I A
authors.initials: IA
authors.lastname: Gardner
mesh_terms: D000818:Animals; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary*; D008297:Male; D010311:Parrots / Q000235:genetics; D012150:Polymorphism, Restriction Fragment Length; D011563:Psittaciformes / Q000235:genetics*; D012016:Reference Values; D012732:Sex Determination Analysis / Q000379:methods / Q000662:veterinary*
chemical_list: D004247:DNA