Rabbi Yossi Feintuch is the rabbi of Congregation Beth Shalom in Columbia, Mo. He is a vegetarian and often discusses a plant-based diet as a Jewish ideal.

Mike Jaynes is a lecturer in the humanities and English at the University of Tennessee at Chattanooga. He has written for About.com about animal rights, including a rebuttal of Christianity’s idea of dominion over the animals.

The Religious Order of the New Compassionests is an interfaith animal ministry in Perryville, Ark., that accepts members and monks.

Chaplain of Pets is an interfaith ministry to pets and their people. It’s based in Stone Mountain, Ga.

James Serpell is a professor of humane ethics and animal welfare at the University of Pennsylvania’s school of veterinary medicine. He directs the Center for the Interaction of Animals and Society.

Andrew Isenberg is a history professor at Temple University in Philadelphia. He is an expert on the history of American environmentalism, especially in the American West. He contributed a chapter on the moral ecology of wildlife to the book Representing Animals.

Katherine C. Grier is professor of material culture studies in the University of Delaware’s Winterthur Program in Early American Culture. She has studied the relationships between humans and animals, and her books include Pets in America: A History (2006).

David Dion DeGrazia is a philosophy professor at George Washington University in Washington, D.C. He has written about the ethics of animal research and is the author of Animal Rights: A Very Short Introduction.

The Rev. Victoria Weinstein is pastor of First Parish Church of Norwell, Mass., a Unitarian Universalist congregation. In May 2006, she delivered a sermon on the spiritual value of animals.