Sperm characteristics following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins in the collared peccary ( Pecari tajacu )

• Published in: Reproductive biology Vol. 15; no. 4; pp. 223 - 228
• Main Authors: Souza, Ana Liza Paz, Lima, Gabriela Liberalino, Peixoto, Gislayne Christianne Xavier, de Souza Castelo, Thibério, Oliveira, Maria Glaucia Carlos, de Paula, Valéria Veras, Silva, Alexandre Rodrigues
• Format: Journal Article
• Language: English
• Published: Poland Elsevier Urban & Partner Sp. z o.o 01-12-2015
• Subjects: Animals; Collared peccary; Cryopreservation - methods; Cryopreservation - veterinary; Cryoprotective Agents - pharmacology; Egg Yolk; Electroejaculation; Freezing; Lipoproteins, LDL; Low density lipoproteins; Male; Obstetrics and Gynecology; Semen cryopreservation; Semen Preservation - methods; Semen Preservation - veterinary; Spermatozoa - physiology; Swine - physiology; Collared peccary; Semen cryopreservation; Electroejaculation; Low density lipoproteins
• ISSN: 1642-431X; 2300-732X
• DOI: 10.1016/j.repbio.2015.10.006

Abstract The aim of the current study was to compare sperm quality characteristics of the collared peccary ( Pecari tajacu ) following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins (LDL). Semen from 11 adult males was obtained by electroejaculation and evaluated for sperm motility, vigor, morphology as well as membrane integrity analyzed by the hypo-osmotic swelling (HOS) test and a fluorescent staining. Moreover, the semen was diluted in a Tris-based extender containing 20% egg yolk (control group) or 5, 10 or 20% LDL (treatment groups). The semen samples were frozen in liquid nitrogen and thawed in a water bath for 60 s at 37 °C. The treatments did not affect ( p > 0.05) sperm vigor, morphology or membrane integrity analyzed by the HOS test. However, post-thaw sperm motility was significantly higher ( p < 0.05) in the extender supplemented with 20% LDL (36.4 ± 5.3%) compared with the egg yolk extender and extender supplemented with 10% LDL. Furthermore, the percentage of membrane-intact frozen-thawed spermatozoa analyzed by the fluorescent staining was significantly higher ( p < 0.05) in the extender supplemented with 20% LDL (27.4 ± 6.5%) than in the other groups. In conclusion, 20% LDL can be used to substitute the whole egg yolk as a cryoprotective additive for freezing semen of the collared peccary.