Implementation of Feed Efficiency in Iranian Holstein Breeding Program.

Area of Science:

• Animal Science
• Agricultural Economics
• Genetics

Background:

• Feed efficiency is crucial for dairy cattle profitability.
• Economic evaluation of traits guides breeding programs.
• Iranian Holstein data is essential for accurate genetic assessments.

Purpose of the Study:

• To assess the economic impact of enhancing feed efficiency in Iranian Holstein breeding.
• To estimate economic values for key production and efficiency traits.
• To adapt international feed efficiency indices for Iranian conditions.

Main Methods:

• Utilized production and economic data from seven Iranian dairy herds.
• Calculated economic weights for traits like milk, fat, and protein yield, and feed intake.
• Conducted a meta-analysis to determine genetic correlations between traits.
• Revised the Iranian selection index and adopted the US Holstein Association's feed efficiency sub-index (FE$).

Main Results:

• Estimated economic values per cow/year: milk yield ($0.34/kg), fat yield ($6.93/kg), protein yield ($5.53/kg), dry matter intake (-$1.68/kg), residual feed intake (-$1.70/kg), productive life ($0.47/month), days open (-$2.71/day).
• Adopted FE$ but noted discrepancies with Iranian genetic coefficients due to differing parameters and economic valuations.
• Revised Iranian selection index to incorporate feed efficiency.

Conclusions:

• Improving feed efficiency is economically valuable for Iranian Holsteins.
• The FE$ requires adaptation with Iranian-specific data for accurate application.
• Further data collection on dry matter intake and genetic evaluations for residual feed intake are recommended for precise economic value estimation.