Factors determining milk quality and implications for production structure under somatic cell count standard modification

Abstract

Consumer and processor demand for high-quality milk has placed increasing pressure on US milk producers to achieve higher product standards. International standards for somatic cell count (SCC) are becoming more stringent, but in May 2011, the United States National Conference on Interstate Milk Shipments chose to retain the 750,000 cells/mL standard. Using ordinary least squares and quantile regressions on US Department of Agriculture Agricultural Resource Management Survey Dairy Costs and Returns Report data for 2005, we model producer and farm-level characteristics associated with SCC. Quantile regression analysis allows for a more parsed inquiry into statistical associations. Dairy Costs and Returns Report data provide cross-sectional information on the physical structure, input expenses, demographics, and outputs for farms in selected states. Location outside the Southeast, lower herd age, full-time farming status, use of biosecurity guidelines, good milking facilities and operations management, and application of related quality tests are all associated with lower SCC levels. Size of operation had little effect on SCC levels after controlling for other factors. Many of the operations that did not attain a more demanding SCC standard of 400,000 cells/mL had older operators, operators who expressed intention to exit within 10 yr, smaller size, and location in the Southeast when compared with those meeting the tighter standard. The results suggest that the stricter scheme favors larger farms that are more committed to production and are less likely to be sole or family proprietorships.