Procyanidin Boosts Turkey Sperm Quality in Cryopreservation

Key Findings

Procyanidin (PC) supplementation at 30 and 50 μg significantly improved post-thaw turkey semen quality and fertility outcomes compared to lower doses (10 μg) and control. Key improvements included enhanced sperm motility, viability, plasma membrane functionality (PMF), total antioxidant capacity (TAC), and superoxide dismutase (SOD) activity. Concurrently, PC at these concentrations reduced DNA damage, abnormal morphology, and lipid peroxidation (measured via MDA levels). Fertility rates after artificial insemination were notably higher with 30 and 50 μg PC, directly linking the antioxidant effects to improved reproductive success. The 10 μg dose showed minimal or no significant benefits.

Study Design

This in vitro study utilized pooled turkey semen diluted in a glucose-based extender. Semen samples were supplemented with procyanidin at 10, 30, or 50 μg concentrations before cryopreservation at -196°C. Post-thaw analysis assessed sperm motility (via CASA), viability (eosin-nigrosin stain), PMF (hypo-osmotic swelling test), DNA integrity (SCSA), morphology, TAC, GPx activity, SOD activity, and MDA levels. Fertility and hatchability were evaluated through artificial insemination of hens using thawed semen. The study design was comparative, testing multiple PC doses against a control extender (no PC). Specific sample size (number of toms/hens) and preservation duration details were not provided in the summary.

Dosage & Administration

Procyanidin was directly added to the semen extender at concentrations of 10, 30, or 50 μg per unit volume of the glucose-based diluent prior to the freezing process. It was not administered orally to the turkeys; supplementation occurred exogenously during semen processing for cryopreservation.

Results & Efficacy

Statistically significant improvements (p<0.05, though exact p-values not detailed in summary) were observed with 30 and 50 μg PC compared to control and 10 μg groups. These doses significantly increased:
- Motility parameters (specific metrics not quantified)
- Viability and PMF
- TAC and SOD activity
- Fertility rates (specific percentage increases not provided)
Concurrently, significant reductions occurred in:
- DNA fragmentation index
- Abnormal sperm morphology
- MDA levels (indicating reduced lipid peroxidation)
GPx activity results were mentioned but specific directional changes or significance were not detailed in the summary. The 10 μg dose generally did not yield significant benefits.

Limitations

Critical limitations include the lack of reported sample size (number of biological replicates/turkeys), absence of detailed turkey demographics (breed, age), and unspecified cryopreservation duration before assessment. Fertility/hatchability results lacked quantitative effect sizes (e.g., percentage points increase). The study focused solely on immediate post-thaw parameters and short-term fertility; long-term embryonic development effects were not evaluated. As an in vitro avian model, direct extrapolation to mammalian or human systems is invalid. No comparison to other common cryoprotectants or antioxidants was made.

Clinical Relevance

This research holds direct relevance for poultry reproduction specialists and artificial insemination programs, demonstrating that adding 30-50 μg procyanidin to semen extenders optimizes cryopreserved turkey sperm quality and fertility. It validates procyanidin's role in mitigating oxidative stress during freezing/thawing. For human supplement users, this study has no direct applicability. Procyanidin was administered exogenously to semen, not ingested orally by the animal. The findings do not support procyanidin or glutathione supplementation for improving human male fertility via oral intake. The relevance is strictly confined to optimizing turkey breeding protocols in agricultural settings.