Roughage level and limited maximum intake regimens for feedlot steers

Area of Science:

• Animal Science
• Ruminant Nutrition
• Beef Cattle Production

Background:

• Optimizing finishing diets for beef cattle is crucial for economic viability.
• Feed intake and roughage levels significantly impact performance and cost of gain.
• Evaluating alternative feeding strategies can enhance cattle production efficiency.

Purpose of the Study:

• To evaluate the effects of restricted energy intake on finishing steer performance.
• To assess the impact of varying roughage inclusion levels and grain sources on steer growth and feed efficiency.
• To determine optimal feeding strategies for reducing roughage use and improving economic returns.

Main Methods:

• 280 Hereford steers were assigned to eight dietary treatments.
• Treatments included feed intake restricted to multiples of maintenance energy (2.1-2.9 MM) or varied roughage levels (2% or 10% RE) with steam-flaked sorghum grain (SFSG) or whole-shelled corn (WSC).
• Performance metrics including dry matter intake (DMI), average daily gain (ADG), gain efficiency, and carcass characteristics were measured.

Main Results:

• The 2.7 MM treatment showed a tendency to improve ADG and gain efficiency compared to ad libitum feeding.
• Steers fed WSC had higher DMI and ADG but lower gain efficiency than those fed SFSG.
• The 2/10 roughage regimen with SFSG improved gain efficiency and reduced roughage use, while the 10/2 regimen showed no significant differences from the 10/10 regimen.

Conclusions:

• Restricted energy intake, particularly at 2.7 MM, may enhance steer performance.
• Steam-flaked sorghum grain generally supports better feed efficiency than whole-shelled corn.
• Reducing roughage during mid-finishing (2/10 regimen) can decrease feed costs and improve gain efficiency, especially with SFSG diets.