Narasin Supplementation Enhances Growth Performance in Grazing Cattle

Area of Science:

• Animal Science
• Ruminant Nutrition
• Beef Cattle Production

Background:

• Grazing beef cattle productivity is influenced by nutritional strategies.
• Optimizing growth performance is crucial for economic viability in beef production.

Purpose of the Study:

• To evaluate the impact of narasin inclusion in supplements on the growth performance of grazing beef cattle.
• To determine if narasin supplementation affects supplement intake in beef cattle.

Main Methods:

• Three randomized complete block design experiments were conducted with Nellore calves and yearlings.
• Animals received mineral or protein supplements with varying levels of narasin (0, 1400, 2100 mg/kg) or a specific level (250 mg/kg).
• Growth performance (average daily gain, final body weight) and supplement intake were monitored over 84-112 days.

Main Results:

• Narasin inclusion consistently increased average daily gain and final body weight across all experiments.
• Significant improvements in average daily gain ranged from 0.048 to 0.082 kg/d.
• Narasin supplementation did not significantly affect supplement intake in any of the trials.
• No dose-dependent effects were observed between 1400 and 2100 mg/kg narasin inclusion.

Conclusions:

• Narasin inclusion in mineral and protein supplements is an effective nutritional strategy to enhance growth performance in grazing beef cattle.
• The benefits were observed across different seasons and production stages without compromising supplement intake.
• This approach offers a means to improve productivity on tropical pastures.