In the 1920s, the average broiler was harvested at 16 weeks and weighed 2.5 pounds. Today, a full grow-out cycle in broiler production can be accomplished in as little as seven weeks and it’s common to have birds weighing upwards of 9 to 10 pounds by eight weeks of age. There have been remarkable transformations in recent decades for increased speed and efficiency of growth rate in animal production. With increased production rates, body weight has also increased, which has translated into increased meat production. But there may be unintended consequences associated with these changes: muscle myopathies.
The term muscle myopathy is used to describe conditions associated with muscle weakness or changes in muscle mass in meat production. Fast growth rate is one of the many factors related to muscle myopathies in a multitude of farm production species. Muscle myopathies are also associated with nutritional composition, genetic abnormalities and management practices. In poultry, myopathies are highly correlated with birds that have been selected for increased growth. Woody Breast Syndrome, white striping and deep pectoral muscle disease are examples of the most common muscle myopathies related to commercial bird production.