When your bulk tank volume takes a plunge through the last bout of heat, do you ever wonder exactly WHY? What is it in the udder that changes to cause the decline? Why do we also commonly see elevated SCC in our tanks too?To best understand the why, the Virgina Tech dairy team collected tissue samples from the mammary gland of cows in controlled environmental chambers. This month we invite Dr. Ben Corl to explain the cellular changes observed in the alveoli, epithelial and even immune cells of the mammary gland of cows undergoing a controlled heat stress challenge.  Additionally, he’ll describe the changes in gene expression in those same tissue samples that controls protein production and mammary health.This continuation of our heat stress series features two papers titled: (1) Cyclical heat stress during lactation influences the microstructure of the bovine mammary gland(2) 2022: Heat stress increases mammary epithelial cells and reduces viable immune cells in milk of dairy cowsTopics of discussionBackground Information:Temperature Humidity Index (THI)#2xAg2030; #journalofdairyscience; #openaccess; #MODAIRY; #heatstress; #alveoli; #milk; #mammarydevelopment; #mammary; #dairysciencedigest; #ReaganBluel;