Successful ram semen cryopreservation with lyophilized egg yolk-based extender

Effect of Propolis Ethanolic Extract Supplementation to Ram Semen Extenders on Sperm Characteristics, Lipid Peroxidation and some Enzymatic Activities in Seminal Plasma in Chilled Semen

“…In this respect, EY in Tris (hydroxymethylaminometahne) extenders achieved less sperm damage during preservation (Khumran et al, 2017). Egg yolk contains some effective antioxidants like phosvitin and α-tocopherol, which have a possibility to reduce chain reactive oxidation and lipid peroxidation of the sperm membrane, (Alcay et al, 2015). Although the favorable effects of egg yolk in extender, but used egg yolk facing many protests mainly attributed to hygiene concerns and risk of bacterial contaminations (Aires et al, 2003).…”

Current status and advances in ram semen cryopreservation

“…Lyophilized or fresh egg yolk Similar cryoprotective effects Alcay et al, 2015 Natural or lyophilized low density lipoproteins Total and progressive motility Moustacas et al, 2011 Casein, palm oil, coconut oil or egg yolk Egg yolk is superior Del Valle et al, 2013 Different species' egg yolk Sperm quality by 15% chucker egg yolk Kulaksiz et al, 2010 -Egg yolk concentration -Bioexcell ® or egg yolk -Optimal concentration: 5-10% -Bioexcell ® may be an alternative Gil et al, 2003 Soybean concentrations between 1-1.5% Motility, viability, membrane integrity - Emamverdi et al, 2013-Forouzanfar et al, 2010 Soybean lecithin or egg yolk 1% soybean lecithin similar with 20% egg yolk extenders Masoudi et al, 2016 Soybean lecithin concentration -Soy lecithin > 1% : semen quality -Soy lecithin > 3.5% : no significant effect on motility -Soy lecithin 3.5% : mitochondrial activity One-step or at 5° C two-steps glycerol addition No effect on motility and viability Morrier et al, 2002 4% glycerol in a two-step dilution (to 2% at 35 o C and to 4% at 5 o C) Good field fertility rate Anel et al, 2003 Osmolality of glycerol based extenders in a two-step dilution High osmotic pressure (400 mOsm) Soylu et al, 2007 Glycerol alone or in combination with trehalose 5% glycerol and 100 mM trehalose: post-thawing sperm quality Najafi et al, 2013 -100 mM trehalose with 5% glycerol -100 mM trehalose and 8% LDL High post-thawing semen quality - Jafaroghli et al, 2011-Tonieto et al, 2010 Trehalose in combination with fructose Motility and viability Matsuoka et al, 2006 Trehalose, sucrose, raffinose, hypotaurine High ram semen cryo-protection - Bucak et al, 2013-Jafaroghli et al, 2011 Cyclodextrins pre-loaded with cholesterol Binding capacity to zona pellucida Mocé et al, 2010 Seminal plasma -Semen quality and fertility rate -No beneficial effect on sperm quality Uysal and Bucak (2007) observed that the addition of lycopene, a natural carotenoid which occurs in certain fruits and vegetables, in a Tris-based extender exhibited high protection of all tested ram semen parameters after thawing. Similar results were obtained by the supplementation of soybean lecithin extender with 4 or 6% rosemary aqueous extract (Motlagh et al, 2014).…”

“…A recent alternative investigation (Alcay et al, 2015) indicated that a modified extender containing lyophilized egg yolk provided similar cryoprotective effects with the fresh egg yolk extender. Additionally, Moustacas et al (2011), who evaluated the suitability of using natural or lyophilized low density lipoproteins, concluded that in terms of post-thaw kinetics, total and progressive sperm motility, natural but not lyophilized LDL were appropriate for cryopreservation of ram semen.…”

Positive effect of BSA supplemented soybean lecithin based extender on liquid storage of ram semen at 5C

“…After incubation, mixture was dropped on a microscope slide and covered with coverslip. At least 200 spermatozoa were evaluated with phase-contrast microscope (Olympus BX51) with a warm slide (38 °C) and sperms that have swollen or coiled tails were counted (5).…”

“…Semen preservation requires a depression or interruption of spermatozoa metabolism which is performed by cryopreservation or liquid storage (29). Ram sperm is more sensitive to cryopreservation than those of other mammalian species because of the polyunsaturated phospholipid membrane structure (5). Liquid storage can be an alternative to cryopreservation of ram semen to avoid detrimental effects of freezing-thawing processes for short time preservation (29).…”