Research

Background

Bovine respiratory disease (BRD) remains the most significant animal health issue facing feedlot cattle. While feedlot managers assess the risk of incoming cattle and determine if on-arrival antibiotic treatment may be necessary, there is increasing scrutiny on the use of antibiotics within the industry. While BRD is multi-factorial with many pathogens and stressors playing a role, some of the main bacteria implicated are Mannheimia haemolytica, Histophilus somni, and Pasteurella multocida. Previous work by this team developed a probiotic cocktail of six Lactobacillus strains administered intranasally at birth, and followed those calves through to the first few weeks of the feedlot feeding period when BRD risk is highest. Calves that received this probiotic had reduced Histophilus and Pasteurella colonization in the lungs after feedlot arrival and performed comparably to calves given antibiotics upon arrival and in-feed. However, this trial had only 14 calves involved per treatment. This project will replicate the previous trial with more animals to determine if the results hold true.

Objectives

The objectives of this project are to:

• Determine the optimal probiotic dose
• Compare the probiotic to antimicrobial treatment in a feedlot setting

Implications of the Research

If successful, this project may provide another tool in the toolbox for mitigating BRD in feedlot cattle.