Dietary concentrate level affects the feed sorting behaviour of lambs

Area of Science:

• Animal Science
• Nutritional Physiology
• Ruminant Nutrition

Background:

• Feed sorting behavior in lambs influences nutrient intake.
• Understanding how forage concentration affects feed sorting is crucial for optimizing lamb diets.

Purpose of the Study:

• To investigate the impact of varying concentrate levels on feed sorting, nutrient intake, and feeding behavior in growing lambs.
• To determine how dietary forage concentration influences particle selection by lambs.

Main Methods:

• A crossover design study involving twelve growing lambs fed two diets: lower-concentrate (LC; 40%) and higher-concentrate (HC; 60%).
• Feed sorting was quantified by analyzing particle size distribution in feed and orts.
• Nutrient intake and feeding behaviors (intake per visit, eating rate, chewing time) were monitored.

Main Results:

• Lambs sorted against long particles (>19 mm) and for fine particles (<1.18 mm) on both diets.
• The preference for fine particles was greater on the LC diet compared to the HC diet.
• Dry matter intake increased with higher concentrate levels, while eating rate increased and chewing time decreased on the HC diet.

Conclusions:

• Growing lambs exhibit selective feed sorting, primarily avoiding long particles and consuming fine particles.
• Dietary forage level significantly influences feed sorting behavior in lambs.
• Lambs on lower concentrate diets demonstrate a more pronounced sorting behavior for fine particles.