Protective effects of fennel (Foeniculum vulgare) extract on frozen-thowed sperm of Ghezel ram

Long term sperm storage is major factor of artificial insemination in animal improvement. Nevertheless recovered fertility of frozen–thawed sperm is very important. This experiment was carried out in order to study of antioxidant effects of fennel (Foeniculum vulgare) aqueous extract on the quality of frozen–thawed Ghezel ram semen. After extraction procedure, different levels of fennel extract (0, 2, 4, 6, 8, 10 and 12 ml as experimental groups) were added per deciliter (dl) of extender. After chilling, diluted semen were packaged in 0.5 ml straws and stored in liquid nitrogen for 3 weeks. This experiment was performed with 5 replications (with 10 straws in each replicates) per experimental groups. Evaluation of live sperm using of eosin-nigrosin staining showed addition of 6 ml Fennel extract had higher live sperm than other experimental groups (P<0.05). Plasma membrane integrity was carried out by Hypo Osmotic Test (HOST) that declared the healthiest membrane was observed in 6 ml extract group (P<0.05). There were significant differences among experimental groups in plasma membrane integrity and lowest value was observed in 12 ml extract group (P<0.05). Sperm motility evaluation by CASA declared significantly higher motility in 6 ml extract group versus other groups (P<0.05). Study of oxidative damage showed lower amount of Malondialdehyde (MDA) in 12ml extract group than other groups (P<0.05). Although the results declare the substantial differences among experimental groups but base on this experiment, It seems, use of 6 ml fennel aqueous extract per dl extender, lead to positive effects on frozen-thawed sperm quality.