title: Effect of chilling temperature on the long-term survival of rabbit spermatozoa held either in a tris-based or a jellified extender.
abstract: As the preservation of the fertilizing capacity of rabbit spermatozoa for several days after semen collection remains a major target for the artificial insemination programs of rabbit breeding, a study was conducted to compare the efficacy of 5 or 15°C as holding temperature in lengthening the preservability of rabbit semen quality during 192 h of storage both in a solid (Cunigel) and a liquid (Tris-Citric acid-Glucose; TCG) extender. Six pooled semen samples (two ejaculates/male; two-three males/pool) were taken and made four aliquots: two aliquots were tenfold diluted with the TCG extender, whereas the other two were tenfold diluted with the Cunigel extender. One aliquot per diluent was stored at 5°C and the second one at 15°C. Sperm motility (light microscope), viability (SyBr-PI staining), plasma membrane functional integrity (Hypo-osmotic swelling test) and acrosome integrity (PSA-FITC staining) were recorded at 0, 48, 120 and 192 h of storage. In liquid-stored spermatozoa, mass motility and viability were significantly higher (p ≤ 0.05) in samples stored at 5°C than at 15°C at all the storage times; at 5°C resulted also higher (p ≤ 0.05) the percentages of both forward motility at 48 h and sperm functional integrity at 120 and 192 h of storage, whereas chilling temperature did not affect acrosome integrity. With the Cunigel extender, all the semen qualitative parameters were significantly higher in sample stored at 5 than 15°C over storage time (p ≤ 0.05); only acrosome integrity at 192 h was not different according to the chilling temperatures. In conclusion, 5°C were better than 15°C for the long-term storage of rabbit semen both in the TCG and Cunigel extender.
authors.affiliation: Department of Animal, Vegetable and Environmental Sciences, University of Molise, via De Sanctis snc, Campobasso, Italy.
authors.forename: Mp
authors.initials: M
authors.lastname: Rosato
authors.forename: N
authors.initials: N
authors.lastname: Iaffaldano
mesh_terms: D020101:Acrosome Reaction; D000818:Animals; D003080:Cold Temperature; D008297:Male; D011817:Rabbits; D055101:Semen Analysis / Q000662:veterinary; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013081:Sperm Motility; D013094:Spermatozoa / Q000502:physiology*