In his attack on PETA and defense of Rubashkin, Rabbi Avi Shafran of Agudath Israel of America writes:
The Jewish religious tradition forbids causing animals unnecessary pain.… But the Jewish faith expressly permits the killing of animals for human needs, including food. Which animals may be eaten and how to dispatch them are topics dealt with at considerable length in Jewish legal literature.
Richard Schwartz of the Jewish Vegetarians of North America, in a response to Rabbi Shafran wants to know why the minutia of kosher laws are observed and safeguarded, while the laws of tzaar baalei hayyim (cruelty to animals) seem to be ignored:
But, why then do Jewish leaders fail to speak out against the many abuses of animals on factory farms? For example, the killing almost immediately after birth of 250 million male chicks [every year] in the U.S. alone at egg-laying hatcheries because they can’t lay eggs and they are not of the breed (broilers) that have been genetically programmed to provide much meat; taking calves from their mothers after one day to raise them as veal; the force feeding of ducks and geese to produce foie gras; raising hens in spaces so small that they can’t raise even one wing, and then debeaking them to prevent them from pecking other hens in their very crowded, unnatural conditions; and much more.
Of course, Mr. Schwartz's question applies equally well to the OU, KAJ and other kosher supervising agencies as well as to the leaders of Agudath Israel, the RCA, Igud HaRabbonim, Agudas HaRabbonim, etc.
Perhaps our rabbinic leaders will answer this important question for us.