WASHINGTON — Milk production in the 23 major producing states totaled 15.165 billion lbs in October, down slightly from 15.170 billion lbs in October 2011, the U.S. Department of Agriculture said in its latest Milk Production report.

Milk production for September was revised to 14.7 billion lbs, down 1% from September 2011 and a decrease of 19 million lbs from last month’s preliminary production estimate.

September production per cow in the 23 major states averaged 1,791 lbs, 1 lb above October 2011. There were 8.47 million dairy cows on farms during the month, 10,000 head less than October 2011 and 8,000 head less than September 2012.