Today, Shaye welcomes Jonathan Wells of the Cargill Animal Nutrition Team to discuss fly control strategies for pasture cattle, focusing on horn flies’ economic impact and how to choose tools for an operation. Wells says horn flies drive about $2 billion in annual losses and can spread diseases like mastitis and anaplasmosis while reducing performance through increased heart rate, higher water intake and urinary nutrient loss, reduced nitrogen retention, and about a 15% drop in average daily gain.  

They compare adult-killing topicals and ear tags (and resistance concerns) with feed-through IGRs like Altosid (methoprene) that break the fly life cycle in manure. Wells explains the Altosid XRB extended-release bolus, given once at season start and releasing IGR for about 195 days, dosing guidance for cows and calves, application tips, compatibility with other controls, and visual signs of adequate control. 

Learn more about Cargill here: https://bit.ly/4e1qygS 

01:33 Why Fly Control Matters 

03:12 Hidden Performance Losses 

05:04 Fly Control Options 

07:24 Breaking The Fly Cycle 

08:24 Altosid XRB Bolus 

10:57 Bolus Release Science 

12:27 Dosing Cows And Calves 

14:08 Safety And Application Tips 

18:17 How To Judge Control 

20:36 Producer Field Experience