8.14: Livestock Production Applications

Transgenic livestock production is rapidly developing, with both current applications and promising future uses.

• Enhanced growth rates and improved feed efficiency
• Improved carcasses with better meat quality
• Modified milk production and composition
• Resistance to diseases such as mastitis in dairy cows
• Production of environmentally friendly animals (e.g., enviropigs that produce less phosphorus waste)

• Animals producing omega-3 fatty acids in meat and milk
• Livestock with enhanced heat tolerance for climate adaptation
• Cattle resistant to trypanosomiasis for African agriculture
• Pigs producing organs suitable for human transplantation
• Chickens resistant to avian influenza

Recombinant bovine somatotropin (rBST) provides an important example of biotechnology in livestock. BST is produced commercially by:

1. Isolating the bovine growth hormone gene
2. Inserting it into E. coli bacteria using plasmid vectors
3. Growing bacteria in large fermentation tanks
4. Extracting and purifying the BST protein
5. Formulating it for injection into dairy cows

The value of rBST includes:

• Increased milk production (10-15% more milk per cow)
• Improved feed efficiency
• Reduced environmental impact per unit of milk produced
• Lower production costs for dairy farmers
• Reduce the need for additional cows to meet milk demand

Image credit: Wikimedia Commons contributors, Link to bovine growth hormone image [commons.wikimedia.org]

---