Dairy cows (IMAGE) Penn State Caption Limited histidine was not considered a challenge for dairy cows fed typical North American diets until research conducted in Alexander Hristov’s lab in the College of Agricultural Sciences at Penn State a few years ago revealed the problem. Now, the team has found that supplemental histidine may help milk production in cattle fed low-protein diets. Credit Penn State Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.