Browse Items (1 total) Browse All Browse by Tag Search Items Browse Map Tags: Advertisement Sort by: Title Creator Date Added Pure Bred Bulls Increase Milk & Butter Fat Production Glass plate negative: Summary of Iowa Experiments. "Pure Bred Bulls Increase Milk & Butter Fat Production". The slide compares milk production of scrub cows and the offspring of a pure bred bull. Tags: Advertisement, Agriculture, Cattle Output Formats atom, dc-rdf, dcmes-xml, json, omeka-xml, rss2