title: Cytogenetics of Dictyocaulus arnfieldi (Cobbod, 1884) Railliet and Henry, 1907.
abstract: A cytogenetic study of Dictyocaulus arnfieldi was made for the first time. The diploid chromosome number was 2n = 11 for males and 2n = 12 for females; there was an XO/XX sex determinism mechanism. Diplotene stage showed bivalents with 3, 2 or 1 chiasmata. The possible differences in the evolution of D. arnfieldi and Dictyocaulus filaria are discussed.
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002477:Cells; D002875:Chromosomes / Q000648:ultrastructure*; D004021:Dictyocaulus / Q000235:genetics* / Q000648:ultrastructure; D005260:Female; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D008938:Mitosis; D009867:Oogonia / Q000648:ultrastructure; D013094:Spermatozoa / Q000648:ultrastructure; D014251:Trichostrongyloidea / Q000235:genetics*