Biomedical subjects

C A Wolf

Publications and source records attributed to C A Wolf.

3 recordsLinked to original sources

PubMed2006

Dairy cattle culling patterns, explanations, and implications.

Culling patterns in the Upper Midwest and Northeast regions were examined from Dairy Herd Improvement records from 1993 through 1999. There were 7,087,699 individual cow lactation observations of which 1,458,936 were complete. A probit regression model was used to determine how individual cow and herd characteristics affected the likelihood of a cow being culled. The model predicted whether individual cows were culled each month. With a combination of observable cow and herd characteristics, as well as variables to capture state, year, and farm effects, the model was able to explain, with a 79.5 and 79.9% accuracy rate, individual cow cull decisions in the Upper Midwest and Northeast regions, respectively. Summer (- 11.5% in the Upper Midwest; - 6.4% in the Northeast) and fall (- 18.7% in the Upper Midwest; - 7.9% in the Northeast) calving vs. spring calving, higher than average milk production (- 1.7% per hundredweight in the Upper Midwest; - 0.5% in the Northeast), higher than average protein content (- 0.2% per additional percentage milk protein in the Upper Midwest; - 0.1% in the Northeast), higher milk production persistency (- 2.1% per additional percent persistent in the Upper Midwest; - 1.8% in the Northeast), and expansion (during the early years following the expansion) were associated with a reduced likelihood of a cow being culled. Lower than average fat content (0.04% per additional percentage butterfat in the Upper Midwest; 0.02% in the Northeast), and higher than average somatic cell count (8.8% for each unit increase in somatic cell count score in the Upper Midwest; 7.8% in the Northeast) were associated with an increased likelihood of a cow being culled. The study results are useful in describing patterns of culling and relating them to cow, herd, geographic, and time variables and can act as a benchmark for producers.

Animals↗

PubMed2003

Custom dairy heifer grower industry characteristics and contract terms.

This study examines a national survey of professional custom heifer growers. Sixty-five respondents from 23 states provided information on operation size and characteristics, management practices, and contract terms. Responding operation current heifer inventories ranged from 30 to 20,000 heifers and the average operation had more than 1200 heifers on-farm. The regional pattern of operation size was similar to the regional pattern of dairy farm size with heifer grower operations in the West and South regions being larger, on average, than those in the Midwest and Northeast regions. On average, 71% of total income was derived from the heifer-growing enterprise. Operations in the Northeast region derived the highest percentage of income from heifer growing while operations in the South region derived the least income from heifer growing activities. Many operations entered business to utilize excess facilities, labor, or feed. A majority of the operations had two to five dairy farm clients. Sixty-nine percent of respondents used some form of written contract. Just over 50% of the respondents indicated that a set daily charge per heifer per day was the primary type of contract payment. Although the most common charge was dollars 1.50 per heifer per day, average daily charge was dollars 1.52/heifer. Operations that took heifers from prior to weaning through to prefresh charged a weighted average daily charge of dollars 1.60 per heifer. Explaining price charges as a function of characteristics and contract terms revealed that size and number of clients were negatively related to price while specialization in heifer growing was positively related to price charged.

Agriculture↗

PubMed2002

Managerial and financial implications of major dairy farm expansions in Michigan and Wisconsin.

This study examines the experiences and results of major dairy farm expansions in Michigan and Wisconsin. Twenty dairy farms that had one-time herd size increases of at least 20% between 1988 and 1998 were selected, surveyed, interviewed, and analyzed. A case study format reveals individual experiences and problem solutions. On average, studied dairy farms increased herd size from 296 to 569 cows. The most commonly cited reason for expansion was increased profits. On average, net farm income and return to operator management and capital improved following expansion. The most profitable expansions were highly correlated with modernizing facilities. In addition, a decline in return on assets was, in several cases, due to taking on too many new partners relative to the increase in herd size. Dairy farms were able to increase milk production and experienced a significant decrease in labor and management expense per hundredweight of milk produced through expansion. Outsourcing and the use of consultants increased with expansion. Public relations problems were not substantial impediments for producers who took a proactive approach. Reflecting on the expansion experience, managers indicated that human resource, financial, operations, herd management, and strategic management skills were the most important skills to achieve a successful expansion.

Administrative Personnel↗