What Ann Barnhardt posted on her page was helpful and logic-driven also. Her background in cattle futures indicates that she's pretty knowledgeable on all things cattle-related. Article is the 2nd one down the page; title begins "Chart of Heat Stress in SW Kansas . . ."
Almost forgot: Her page is at www.barnhardt.biz
Sorry, my mistake — it’s actually the 3rd article down on Barnhardt’s page, titled “UPDATED: As a cattle person, I need to weigh-in on the “mass cattle die-off” video that’s going around”.