Early and accurate pregnancy diagnosis is one of the most valuable tools in dairy and beef herd management, directly affecting calving intervals, feed allocation, and culling decisions. This colloidal gold lateral flow test detects Pregnancy-Associated Glycoproteins (PAGs) in bovine serum or plasma, offering a simple, visual, on-farm alternative to rectal palpation or ultrasound. Results develop within minutes and require no specialized equipment, making it practical for use directly at the farm gate or in a field vet's kit. Regular pregnancy screening using tools like this helps reduce the average days-open per cow, a key driver of dairy herd profitability. Shelf life is 18 months when stored at 2-30°C.