In vitro fertilization of horse follicular oocytes matured in vitro.

The study investigates the in vitro fertilization capability of stallion sperm using horse follicular oocytes that also matured in vitro. This was done using various treatments on collected stallion sperm before co-incubating them with the oocytes.

Experimental Procedure

• The research sought to assess the effectiveness of in vitro (outside the body) fertilization performed by stallion sperm cells using horse follicle eggs that were matured in controlled laboratory conditions.
• Following collection, the stallion sperm cells went through different treatment procedures. These procedures comprised incubation in specific solutions and under predetermined conditions.

Treatment Procedures

• For the first treatment, the spermatozoa were washed and kept in TALP (Tyrode’s albumin lactate pyruvate) medium supplemented with 3 mg/ml bovine serum albumin (BSA) and 10 micrograms/ml of heparin for 4 hours.
• The second treatment procedure involved washing the spermatozoa and incubation in TALP with 3 mg/ml BSA for 3 hours. After this, it was cultured for an additional 1 hour with 1mM of caffeine and 5 mM of dbcAMP.
• The third method entailed washing the sperm and incubating them in a TALP medium containing 3 mg/ml BSA at a pH range of 7.9-8.2 for 2-4 hours.
• The fourth treatment process diluted the sperm and incubated it in a TALP medium with 10 mg/ml BSA and a calcium ionophore called A 23187 for 5-10 minutes. After this, the sperm was washed.

Results and Conclusion

• After the respective treatment, the sperm suspensions were diluted into a B2 medium to a concentration of 5×10(6) sperm/ml and co-incubated with the oocytes for varying timeframes -12 hours or 24-48 hours.
• The results showed successful fertilization in the ionophore-treated group, where 33% of oocytes were fertilized by 12 hours, and 24% of the fertilized oocytes had cleaved by 24-48 hours. This provides evidence of fertilization in the oocytes.
• However, the study couldn’t find any indicators of successful fertilization in oocytes exposed to spermatozoa from the other treatment procedures.