regional model are appropriate, but the committee has concerns about the analysis for reasons noted below.


Descriptions of the model and scenarios in the uSSRA are sometimes inaccurate. The partial equilibrium model is described as temporal and spatial; the latter is inaccurate. The model is temporal in that it solves dynamically to capture the lags inherent in animal and crop production. The model is not spatial inasmuch as it treats the United States as a point in space, so the uSSRA text incorrectly implies that the model handles regional differences in production and consumption and hence regional trade, which the model is not capable of handling.

The uSSRA also states that observed values are used for the 2009–2018 model baseline (p. 546), but observed values are only possible for 2009 and 2010 and not future timeframes. For 2011–2018, the model baseline is the annual U.S. Department of Agriculture (USDA) baseline from February 2011 converted into quarterly values. That means that there is more fluctuation in the 2009 and 2010 results because the USDA baseline tends to smooth out. The FMD supply shocks are introduced into the more variable baseline values. The inclusion of farm programs based on the 1996 and 2002 farm bills is mentioned on p. 545 of the uSSRA, but this version of the model incorporates the 2008 farm bill and the Average Crop Revenue Election (ACRE) program. Given the baseline crop prices, the only change in government payments to crop producers is via ACRE unless reduced feed consumption causes crop prices to fall enough to trigger traditional commodity program payments. Thus, the timeframe of 2009–2018 matters for the results because changes in U.S. government payments will not buffer losses in returns to crop growers except for the small share of production enrolled in ACRE.

In the uSSRA, there is a tendency for the text to refer to cattle, and this leaves the situation for other species vague. For example, it is unclear whether the vaccinate-to-live strategy applies to swine and sheep as well as to cattle. The uSSRA should have described the domestic demand shocks as percentage reductions in domestic demand rather than as consumers dropping meat consumption, because consumers could reduce consumption without completely avoiding red meats.


The quality of the estimates of economic impacts depends on input from the North American Animal Disease Spread Model, correct operation of the economic models, and decisions on scenario design. The magnitudes of livestock depopulation are estimated in the epidemic modeling. Those

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