title: Selection and utilization of spermatozoa in the reproductive tract of the female zebra finch Taeniopygia guttata.
abstract: The numbers and proportion of spermatozoa reaching different parts of the female reproductive tract after a single natural insemination were investigated in zebra finches Taeniopygia guttata. The number of spermatozoa transferred during a single, natural copulation was estimated by comparing the number of spermatozoa in the seminal glomera of males that had performed a single copulation with control males. The mean number of spermatozoa per ejaculate was 5.8 x 10(6) +/- 1.80 x 10(6) SEM. The mean number of spermatozoa stored in the sperm storage tubules in the uterovaginal junction following a single, natural insemination was 6027 +/- 1874, 0.104% of those inseminated. The mean number of spermatozoa reaching the infundibulum and trapped on the perivitelline layer of all eggs of the clutch after a single copulation was 45.6 +/- 9.18 and a further 36 penetrated the perivitelline layer of the ovum, i.e. 82 in total (1.4% of the spermatozoa in the sperm storage tubules and 0.001% of spermatozoa in the ejaculate). Female zebra finches that completed a natural breeding cycle with a mean of 12 copulations had 404 +/- 111 spermatozoa trapped on the perivitelline layer of all eggs of the clutch, and an estimated further 173 spermatozoa penetrated the perivitelline layer. A smaller proportion of spermatozoa was trapped on the perivitelline layer of zebra finch eggs, than in chicken or turkey eggs.
authors.affiliation: Department of Animal and Plant Sciences, The University, Sheffield, UK.
authors.forename: T R
authors.initials: TR
authors.lastname: Birkhead
authors.forename: E J
authors.initials: EJ
authors.lastname: Pellatt
authors.forename: F
authors.initials: F
authors.lastname: Fletcher
mesh_terms: D000818:Animals; D001717:Birds / Q000502:physiology*; D005260:Female; D005836:Genitalia, Female / Q000166:cytology; D008297:Male; D013076:Sperm Count; D013083:Sperm Transport / Q000502:physiology*; D013084:Sperm-Ovum Interactions / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology*