title: Semen characterization, seasonality of production, and in vitro sperm quality after chilled storage and cryopreservation in the king penguin (Aptenodytes patagonicus).
abstract: Research was conducted to examine seasonal seminal traits and to establish short-term and long-term sperm preservation methods in the king penguin (Aptenodytes patagonicus) for use in genome banking and artificial insemination (AI). Spermic ejaculates (n = 87) obtained using a cooperative method were collected across multiple (n = 6, Male 1) and a single (Male 2) breeding season(s). Non-contaminated ejaculates (n = 69) were 0.36 ± 0.32 ml at 56.3 ± 62.7 × 10(7)  sperm/ml with 85.3 ± 10.6% total motility (TMot), 52.5 ± 12.9% progressive motility (PMot), 86.6 ± 24.3 µm/sec average path velocity (VAP) and 92.3 ± 3.7% plasma membrane intact. In vitro quality of chilled semen was best maintained over 48 hr at 5°C than 21°C, with decreased (P < 0.05) motility and morphology parameters observed by 24 and 6 hr, respectively. A comparison of two freezing methods (straw [STR] vs. directional [DF]) demonstrated similar effects on post-thaw quality at 0 and 3 hr, with the exception of plasma membrane integrity which was higher (P < 0.05) at 0 hr for DF (48.7 ± 6.5%) than STR (41.2 ± 7.0%). At 0 hr post-thaw, DF samples retained 46%, 69%, and 52% of their initial PMot, VAP, and plasma membrane integrity, respectively. Normal morphology of motile cells was reduced (P < 0.05) during freeze-thawing from 84% post-collection to 37% and 34% at 0 and 3 hr post-thaw, respectively. Results indicate that chilled and cryopreserved semen from the king penguin has potential for use in AI.
authors.affiliation: SeaWorld and Busch Gardens Reproductive Research Center, SeaWorld Parks and Entertainment, San Diego, California.
authors.forename: Justine K
authors.initials: JK
authors.lastname: O'Brien
authors.forename: Todd R
authors.initials: TR
authors.lastname: Robeck
mesh_terms: D000818:Animals; D003080:Cold Temperature; D015925:Cryopreservation / Q000662:veterinary*; D008297:Male; D012621:Seasons; D055101:Semen Analysis / Q000662:veterinary*; D012662:Semen Preservation / Q000662:veterinary*; D013081:Sperm Motility; D046429:Spheniscidae / Q000502:physiology*
keywords: CASA; avian; directional freezing; genome bank, penguin, morphology, sperm cryopreservation