Des Moines Register 05-17-07 Extensive literature rebuts ISU sow study The article regarding the sow housing study at Iowa State University failed to mention a result far more important than the advantage in live-born pigs for the hoop-gestated sows ("ISU Study Stirs Debate About Crates for Sows," May 11). The stall-gestated sows weaned 0.1 more pigs than the hoop sows. The 11 percent supposed advantage [in production costs from using group housing] took into account the former fact (which has no value), not the fact that only live weaned pigs are marketable. An extensive study of all the literature published on research of sow gestation effects on sow welfare and performance, conducted by a task force on sow housing of the American Veterinary Medical Association, showed no advantage of group housing over stall housing, and the ISU study concurs. Further, the Humane Society of the United States and Farm Sanctuary have taken the position that economic considerations should never have any bearing on matters of animal welfare. This negates any perceived and/or imaginary advantages one might read into the ISU study. Every study that finds group housing to be preferable to stalled housing states that the level of human guidance (stockmanship) necessary for those systems to succeed must be superior to that in stalled systems. Unfortunately, no one has identified a source of these superior caretakers. Wayne Pacelle and his minions at the Humane Society certainly aren't willing to sully their hands for the wages available in agriculture. - D.P. Madsen, D.V.M., diplomate, American Board of Veterinary Practitioners, swine health management, Iowa Falls.