Protein supplementation reduces non-grass foraging by a primary grazer

Area of Science:

• Ecology
• Animal Nutrition
• Rangeland Management

Background:

• Wildlife and livestock compete for limited forage in semiarid savannas.
• Livestock grazing seasonally impacts protein-rich forbs crucial for wildlife.
• Previous assumptions about livestock protein needs lacked experimental validation.

Purpose of the Study:

• To experimentally test if protein supplementation alters cattle diet selection in a mixed wildlife-livestock rangeland.
• To evaluate the effects of dietary changes on cattle behavior, nutrition, and performance.
• To assess the potential of protein supplementation for managing wildlife-livestock competition.

Main Methods:

• Compared forage selection in protein-supplemented vs. un-supplemented cattle during dry and wet seasons.
• Analyzed diet quality (crude protein, digestible organic matter), intake, and live mass change.
• Monitored biting and movement rates to assess behavioral impacts.

Main Results:

• Supplemented cattle significantly reduced forb consumption by 76% during the dry season.
• Cattle shifted to selecting more abundant grasses (Brachiaria lachnantha) and less preferred grasses (Bothriochloa insculpta) when supplemented.
• No significant negative effects on cattle behavior, nutrition, or performance were observed.

Conclusions:

• Protein supplementation can modify cattle foraging behavior, reducing competition for forbs with wildlife.
• Cattle can substitute protein-rich forbs with grasses without adverse consequences.
• Protein supplementation offers a viable strategy for enhancing coexistence between livestock and wildlife in savanna ecosystems.