Preservability of rabbit semen after chilled storage in tris based extender enriched with different concentrations of Propolis ethanolic extract (PEE)

Objective:To maintain semen quality of male rabbits during chilled storage by enrichment the tris based diluent with different concentrations of propolis ethanolic extracts.Methods: Total phenolic and total flavonoid contents, as well as antioxidant activity was determined in propolis ethanolic extract (PEE). The extract was analysed by HPLC for separation and identification of target metabolites. Semen was collected from 10 rabbit bucks, pooled, then divided into five aliquots (each of 500 μL) and diluted each in 5 mL Tris-citric acid-glucose-egg yolk extender (TCGY). The 1st aliquot served as control while PEE was added at concentration of 0.8, 1.2, 1.6 and 2.0 mg/5 mL tris extender in the aliquot 2, 3, 4 and 5 respectively. Diluted semen samples were subjected to cooling at 4℃ for 72 h. Sperm motility, sperm viability, sperm abnormality, sperm membrane integrity and acrosome integrity were evaluated in chilled semen allover the chilling period.Results:The resluts revealed presence of a considerable amount of total phenolic compounds (98.67 mg GAE/g extract) and total flavonoids (70.16 mg CE/g extract) which were parallel to an antioxidant activity assessed as ABTS, DPPH and FRAP (198.65, 180.18 and 306.17 mM TE/g extract respectively). The dominant phenolic acid was chlorogenic acids (3.959 mg/g extract). Other compounds were found in less amounts rosmarinic acid (3.959 mg/g extract), myrcetin (1.946 mg/g extract), kaempferol (1.089 mg/g extract) and apeginin-7-glucoside (1.113 mg/g extract). Obtained results clearly demonstrated that the addition of (1.2-1.6) mg PEE in the chilled extended rabbit semen proved to be beneficial for maintaining semen characteristics compared to control and the addition of 0.8 and 2 mg PEE.Conclusions: The enrichment of rabbit semen tris-basic extender with (1.2-1.6) mg PEE/5 mL tris-extender (as the best and safe concentrations) maintain the sperm characteristics in good condition all over 72 h of chilling.

Cryopreservation of cattle semen using coconut water extender with different glycerol concentrations

Objective:To investigate the effect of coconut water with a lone concentration and different concentrations of glycerol on chilled and cryopreserved cattle semen characteristics.Methods: Semen was collected from five mature cattle bulls, at weekly intervals for 5 weeks. The ejaculates were pooled and evaluated for dilution processing. Tris citrate egg yolk fructose was used as control treatment for semen, while 50% (V/V) coconut water, 25% (V/V) bi-distilled water and 25% (V/V, 5% anhydrous monosodium citrate) to 20 mL egg yolk and three different concentrations of glycerol (4%, 6% and 8%) were used as coconut water (CW)-glycerol-yolk extenders (CWCG-4, CWCG-6 and CWCG-8). Extended semen was cooled and cryopreserved. Sperm motility%, sperm membrane integrity%, normal acrosome%, live sperm% and total sperm abnormalities% were recorded after equilibrium and after freeze-thawing.Results:The addition of 4% glycerol to coconut water enriched media (CWCG-4) revealed the most effective addition of glycerol on all parameters after equilibrium and after freeze-thawing.Conclusions:Coconut water enriched media with 4% glycerol addition is safe to be used as an extender in bull semen preservation because it is a sterile liquid. So, it can be used without addition of antibiotics to the extender, as antibiotics have to some extent hazardous effect on spermatozoa.