A DEMONSTRATION PROJECT OF INTERDISCIPLINARY DAIRY-HERD EXTENSION ADVISING FUNDED BY INDUSTRY AND USERS .2. IMPACT ON HERD PERFORMANCE

The objectives of this 24-herd, demonstration project of extension adv ising were to measure the impact of integrated problem solving on meas ures of DHI performance for 2 yr during and 2 yr after the project. Du ring project advising, increases in rolling herd average milk and fat yields and 3.5% FCM were similar for project and state herds. When rol ling herd average for milk yield for state herds was adjusted for two USDA milk reduction programs, milk yield of project herds was estimate d to have increased 434 lb more per cow than that of DHI state herds. Compared with state DHI trends, project producers significantly improv ed in percentage of low SCC, days open, and age at first calving. Two years postproject, DHI milk yield declined for project and state herds , probably because of drought. Demonstration herds did not outperform state DHI herd average in milk yield or in other efficiency parameters during the 2-yr postproject. The extension advising in the demonstrat ion project had the most positive impact on management of low ranking herds. Only low ranking herds had an advantage in rate of improvement, compared with high ranking herds, in rolling herd average for milk yi eld during and after the project and in SCC and days open during the p roject. Gains by managers of herds ranking low and in the middle in DH I parameters were generally lost or declining postproject.