Annual estimates of the number of livestock producing operations in the US continue to show steadily declining numbers, but surprisingly little impact from last year’s drought event.

There remain 734,000 beef cow operations in the US, according to US Department of Agriculture survey figures, down 8000 from 2010.

The 2011 number is just over 160,000 lower than a comparative survey conducted in 1993, however. The land-extensive nature of cow-calf operations and the fact that there are few other uses of grasslands were major reasons put forward by analysts for the large number of beef cow operations.

When it comes to number of operations, small herds still dominate the US beef cow sector. There were still 583,000 herds with inventories of 1-49 cows last year. That’s down 5000 from the 2010 count, but is generally on the same trend line that has existed since 2004.

The next two smallest categories (50-99 head and 100-499 head) also lost numbers in 2011, declining by 1000 to 81,000 producers and 2100 to 64,200 producers respectively.

Large beef cow operations are still rare in the US. Across the entire country, there were only 50 operations with 5000 or more cows and only 280 with 2000-4999 cows. An estimated 5,470 operations had 500-1999 beef cows last year. Numbers for all of those size categories have been stable since 1998 when they were first estimated by USDA.

Operations with fewer than 500 cows held 83 percent of all of the cows in US inventory in 2011, little changed from 86 percent in 1993. Those three smallest categories accounted for 99pc of all calf producing operations in the US.

Analysts suggest the figures signal that barely half of the US national herd is in hands that ‘depend upon those cows for a living’, suggesting there is a substantial portion of the beef supply chain that might not respond predictably or quickly to economic signals.