Towards a Sustainable Reproduction Management of Dairy Sheep: Glycerol-Based Formulations as Alternative to eCG in Milked Ewes Mated at the End of Anoestrus Period.
Authors: Sotgiu Francesca D, Porcu Cristian, Pasciu Valeria, Dattena Maria, Gallus Marilia, Argiolas Giuseppe, Berlinguer Fiammetta, Molle Giovanni
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Researchers at the University of Sassari explored whether glycerol-based oral supplementation could replace equine chorionic gonadotrophin (eCG) in oestrous synchronisation protocols for late-lactation dairy ewes, addressing both cost and sustainability concerns in reproductive management. Forty-eight Sarda ewes received either a glucogenic mixture (70% glycerol with propylene glycol) or water twice daily for four days before sponge withdrawal and ram introduction, with only the control group receiving the standard 200 IU eCG injection. Remarkably, reproductive outcomes were identical between groups, whilst the glycerol-treated ewes demonstrated significant metabolic shifts—elevated blood glucose, insulin and triglycerides alongside reduced cholesterol and non-esterified fatty acids—without compromising milk yield or composition (except expected changes in milk glycerol and urea concentrations). For practitioners managing seasonal breeding in dairy sheep, this work suggests that oral glycerol supplementation offers a practical, economical alternative to hormone administration during the critical synchronisation window, potentially reducing reliance on exogenous gonadotrophins whilst maintaining conception rates. The metabolic benefits observed—particularly improved insulin sensitivity and lipid profiles—may carry additional welfare advantages during the metabolically demanding late-lactation period.
Read the full abstract on PubMed
Practical Takeaways
- •Glycerol-based oral formulations may offer a cost-effective and sustainable alternative to eCG injections for reproductive synchronization in dairy sheep without compromising fertility outcomes
- •Metabolic parameters improve with glycerol supplementation during critical reproductive windows, which may support overall herd health management
- •This approach aligns with sustainable farming objectives by reducing hormone dependency while maintaining production efficiency
Key Findings
- •Glycerol-based formulation (70% glycerol, 20% propylene glycol, 10% water) produced equivalent reproductive outcomes to eCG treatment in synchronized ewes
- •GLU group showed significantly higher glycemia (p<0.001), insulinemia (p<0.05), plasma glycerol (p<0.001), and triglycerides (p<0.001) compared to controls
- •No differences in reproductive performance metrics between glycerol-treated and eCG-treated groups
- •Milk yield and composition unaffected by treatment except for elevated milk glycerol and reduced milk urea in GLU ewes