PhD from Ohio State University
Graduate fields: Animal Science
Area(s) of interest: dairy cattle management
Teaching:
- Dairy Cattle Production- AS 250
- Dairy Cattle Selection - AS 251
- Dairy Herd Management - AS 351
- Dairy Management Fellowship - AS 456
Current Research:
During the past ten years, my research program has been designed to question the traditional dairy management recommendations in order to continue to improve productivity and profitability. The research areas have been the long-term use of bST on dairy herd performance; optimum lactation and calving interval lengths on herd performance and profitability for herds using bST; calving heifers earlier in life for greater profitability by achieving accelerated body growth without detrimental effects on lactation performance; and use of prostaglandin during the postpartum period to improve reproductive performance and associated profitability.
The bST field studies focused on monitoring herd performance relative to management level. Six cooperating herds were utilized over five years as case farms for developing management recommendations for producers and consultants. The experiences gained from these studies helped New York dairy producers to widely adopt the use of bST.
Upon the commercialization of bST, a field study was implemented to determine the optimum reproductive management strategies for maximizing profit per day of productive life. With the use of bST technology, lactation curves are altered, with higher peak milk yields with greater persistency. Thus, the potential may exist for recommending different reproductive management strategies, mainly calving interval lengths. Treatments in the current field study of ten herds, include delayed breeding of cows in order to lengthen calving intervals, and not to breed cows again after the second lactation. The preliminary data indicate that extended calving intervals of up to 18 months increased profitability per life. The profitability is associated with greater milk income over feed costs, reduced heifer costs, and lower annual health costs. The cattle that were not bred back were not persistent in their lactations.
With the availability of excellent quality and quantity of roughages on farms and the ability to grow heifers well, a long-term research project was developed to determine the effects of the interaction of varying level of energy and quality of protein sources relative to daily rate of body gain and body condition, especially prior to puberty, on subsequent lactation milk yields. Accelerated body growth, with no detrimental effects on lactation performance, may be profitable for dairy producers in decreasing age at first calving, thus decreasing variable costs of raising heifers and capital investment requirements, and increasing percent days of productive life. Results indicate that heifers can gain 1 kg per day prior to puberty without detrimental effects on lactation milk yield. Subsequent studies will investigate the interrelationship of rate of body gain, age at first calving and body weight at first calving in relation to mature body weight on profitability per cow.
Recent research has indicated that traditional postpartum reproductive therapy does not improve overall reproductive performance. With the mode of action of prostaglandin known, it may be of value in improving reproductive performance, especially when used during the postpartum period and for estrus synchronization. Thus, a three herd (1,400 cows) study was carried out to compare the use of prostaglandin for postpartum therapy and estrus synchronization, with rectal palpation and traditional therapy practices. The recently completed study indicated that the use of prostaglandin (compared with traditional practices) increased pregnancy rate and d ecreased reproductive costs. Currently, field studies are being conducted to examine the potential of various heat detection methods in conjunction with prostaglandin to further improve overall herd reproductive performance and reduce costs.