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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.

The objective of this study was to determine if increasing the energy and protein intake of heifer calves would affect growth rates, age at puberty, age at calving, and first lactation milk yield. A second objective was to perform an economic analysis of this feeding program using feed costs, number of nonproductive days, and milk yield data. Holstein heifer calves born at the Michigan State Dairy Cattle Teaching and Research Center were randomly assigned to 1 of 2 dietary treatments (n=40/treatment) that continued from 2 d of age until weaning at 42 d of age. The conventional diet consisted of a standard milk replacer [21.5% crude protein (CP), 21.5% fat] fed at 1.2% of body weight (BW) on a dry matter basis and starter grain (19.9% CP) to attain 0.45 kg of daily gain. The intensive diet consisted of a high-protein milk replacer (30.6% CP, 16.1% fat) fed at 2.1% of BW on a dry matter basis and starter grain (24.3% CP) to achieve 0.68 kg of daily gain. Calves were gradually weaned from milk replacer by decreasing the amount offered for 5 and 12 d before weaning for the conventional and intensive diets, respectively. All calves were completely weaned at 42 d of age and kept in hutches to monitor individual starter consumption in the early postweaning period. Starting from 8 wk of age, heifers on both treatments were fed and managed similarly for the duration of the study. Body weight and skeletal measurements were taken weekly until 8 wk of age, and once every 4 wk thereafter until calving. Calves consuming the intensive diet were heavier, taller, and wider at weaning. The difference in withers height and hip width was carried over into the early post-weaning period, but a BW difference was no longer evident by 12 wk of age. Calves fed the intensive diet were younger and lighter at the onset of puberty. Heifers fed the high-energy and protein diet were 15 d younger at conception and 14 d younger at calving than heifers fed the conventional diet. Body weight after calving, daily gain during gestation, withers height at calving, body condition score at calving, calving difficulty score, and calf BW were not different. Energy-corrected, age-uncorrected 305-d milk yield was not different, averaging 9,778 kg and 10,069 kg for heifers fed the conventional and intensive diets, respectively. However, removing genetic variation in milk using parent average values as a covariate resulted in a tendency for greater milk from heifers fed the intensive diet. Preweaning costs were higher for heifers fed the intensive diet. However, total costs measured through first lactation were not different. Intensified feeding of calves can be used to decrease age at first calving without negatively affecting milk yield or economics.

The 2003 blackout in the northern and eastern U.S. and Canada which caused a $6 billion loss in economic revenue is one of many indicators that the current electrical grid is outdated. Not only must the grid become more reliable, it must also become more efficient, reduce its impact on the environment, incorporate alternative energy sources, allow for more consumer choices, and ensure cyber security. In effect, it must become "smart." Significant investments in the billions of dollars are being made to lay the infrastructure of the future Smart Grid. However, the authors argue that we must take great care not to sacrifice consumer privacy amidst an atmosphere of unbridled enthusiasm for electricity reform. Information proliferation, lax controls and insufficient oversight of this information could lead to unprecedented invasions of consumer privacy. Smart meters and smart appliances will constitute a data explosion of intimate details of daily life, and it is not yet clear who will have access to this information beyond a person's utility provider. The authors of this paper urge the adoption of Dr. Ann Cavoukian's conceptual model 'SmartPrivacy' to prevent potential invasions of privacy while ensuring full functionality of the Smart Grid. SmartPrivacy represents a broad arsenal of protections, encapsulating everything necessary to ensure that all of the personal information held by an organization is appropriately managed. These include: Privacy by Design; law, regulation and independent oversight; accountability and transparency; market forces, education and awareness; audit and control; data security; and fair information practices. Each of these elements is important, but the concept of Privacy by Design represents its sine qua non. When applying SmartPrivacy to the Smart Grid, not only will the grid be able to, for example, become increasingly resistant to attack and natural disasters-it will be able to do so while also becoming increasingly resistant to data leakage and breaches of personal information. The authors conclude that SmartPrivacy must be built into the Smart Grid during its current nascent stage, allowing IDIS (2010) 3:275-294

Animal welfare concerns are having dramatic impacts on food and livestock markets. Here we examine consumer preferences for pork products with a focus on use of gestation crates. We examine underlying consumer valuations of pork attributes while considering preference heterogeneity as well as voluntary and legislative alternatives in producing gestation crate-free pork. Our results suggest that prohibiting swine producers from using gestation crates fails to improve consumer welfare in the presence of a labeling scheme documenting voluntary disadoption of gestation crates. Consumers are found to implicitly associate animal welfare attributes with smaller farms. Preference heterogeneity drives notably diverse consumer welfare impacts when pork produced with use of gestation crates is no longer available for consumption.

We use a two-state linear control model to examine the socially optimal management of disease in a valuable wildlife population when diseased animals cannot be harvested selectively. The two control variables are nonselective harvests and supplemental feeding of wildlife, where feeding increases both in situ productivity and disease prevalence. We derive a double singular solution which depends on the initial state and does not require bang-bang controls. The case of bovine tuberculosis among Michigan white-tailed deer is analyzed. In the base model, the disease is optimally maintained at low levels, with intermittent investments (via feeding) in deer productivity. Copyright 2005, Oxford University Press.

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