FORT COLLINS, Colo. – According to animal welfare expert Dr. Temple Grandin, who writes exclusively for Meat&Poultry, the lameness issues linked to the use of beta-agonists in cattle feed vary in severity based on many factors. Welfare issues such as sore and stiff feet among cattle fed beta-antagonists, including Zilmax, which has been removed from US and Canadian markets, are a negative result of what happens “when you push the biology of the animals too much.”

She tells Meat&Poultry that while makers of Zilmax, Merck Animal Health, are working to investigate links to the feed supplement and reports of lameness, there is an effective and objective method of scoring feedlot cattle currently being used by several beef processors. Based on this scoring system, if more than 10 percent of cattle would qualify as ‘mildly lame,’ “That’s a sign you have a major problem,” that shouldn’t be ignored, according to Grandin. “We don’t want to get to the point where bad is normal,” she adds. “Lame and stiff cattle can’t be accepted as normal.”


Based on her observations and research, Grandin says the lameness issues are more prevalent among larger animals and during hot weather. Scoring, she says, should be done at the plant level, after cattle have been shipped from feedlots. “Most of them look just fine at the feedyard,” she says, but symptoms seem to worsen after they go through the holding pen period and also the transporting process.

“If cattle on beta-agonists have lameness problems, they tend to get worse as they move through the handling and transport steps to get from the feedlot and through the plant,” she says.
“Therefore, it is essential to score lameness at both unloading at the packing plant and when the cattle move out of the holding pens for either ante-mortem inspection or to go to the stunner.”

The scoring system recommended by Grandin is below.

Reluctance to Move Scoring for Fed Cattle on Beta-Agonists

0 = Normal — Stands and walks normally, long confident strides, easy to move and vigorous

1 = Mildly Lame — Slightly stiff gait, sore footed, keeps up with normal cattle when the group is walking.

2 = Moderately Lame — Lags behind and fails to keep up with normal cattle when the group is walking. Head down, stiff gait, sore footed. When at rest, animal may shift weight back and forth between different feet.

3 = Severely Lame and Reluctant to Move — Does not want to move, no flight zone, has difficulty moving and handlers have to put their hands or driving aids on the animal to induce it to walk.

4 = Downed Cattle — Includes cattle that are down and not able to stand, dead or severe damage to hooves.