Incorporating the carbon sub index into Irish sheep breeding program
Abstract
Background
Efforts to reduce greenhouse gas (GHG) emissions have intensified in agricultural sector. Despite these efforts CH4 emissions have not been part on any sheep breeding program. In Ireland sheep breeding goals currently focus on production, maternal, lambing, and health traits. Incorporating carbon in the selection index could facilitate genetic selection of GHG. This study aims to add a carbon sub index into the existing national sheep breeding Index.
Methods
A Teagasc sheep life cycle assessment model was used for calculation of GHG for traits which impact GHG. The economic value of carbon was calculated as a change in total GHG emissions per unit change in the trait holding all other traits constant. Selection indexes were developed to access the impact of carbon on both terminal and replacement indices.
Results
The carbon economic value was: - €0.19 lamb surviving at birth, €20.08 number of lambs born, € 0.03 ewe mature weight (replacement), € 0.17 ewe mature weight (maintenance), € 0.09 days to slaughter (per day), € 0.15 carcass fat (per score). Carbon constitutes 9.96% in terminal index and 17.86% in replacement index.
Conclusion
Positive economic values for carbon shows that improving specific traits can increase GHG emissions. However, other traits are complementary, suggesting it is possible to strike a balance between reducing emissions and enhancing profitability. The replacement index places higher emphasis on carbon emissions than terminal index as it aims to produce ewes that will remain in the flock for the next breeding season.
Incorporating the carbon sub index into Irish sheep breeding program
Background
Efforts to reduce greenhouse gas (GHG) emissions have intensified in agricultural sector. Despite these efforts CH4 emissions have not been part on any sheep breeding program. In Ireland sheep breeding goals currently focus on production, maternal, lambing, and health traits. Incorporating carbon in the selection index could facilitate genetic selection of GHG. This study aims to add a carbon sub index into the existing national sheep breeding Index.
Methods
A Teagasc sheep life cycle assessment model was used for calculation of GHG for traits which impact GHG. The economic value of carbon was calculated as a change in total GHG emissions per unit change in the trait holding all other traits constant. Selection indexes were developed to access the impact of carbon on both terminal and replacement indices.
Results
The carbon economic value was: - €0.19 lamb surviving at birth, €20.08 number of lambs born, € 0.03 ewe mature weight (replacement), € 0.17 ewe mature weight (maintenance), € 0.09 days to slaughter (per day), € 0.15 carcass fat (per score). Carbon constitutes 9.96% in terminal index and 17.86% in replacement index.
Conclusion
Positive economic values for carbon shows that improving specific traits can increase GHG emissions. However, other traits are complementary, suggesting it is possible to strike a balance between reducing emissions and enhancing profitability. The replacement index places higher emphasis on carbon emissions than terminal index as it aims to produce ewes that will remain in the flock for the next breeding season.