Characteristics of cattle in chronic pens at 17 North American feedlots

Ill and injured cattle in feedlot chronic pens are an understudied population, and the limited information on this vulnerable population has implications for animal health, welfare, and operational viability. The objective of this study was to describe demographics, diagnoses, and final dispositions of cattle in chronic pens. Seven years of chronic cattle records from 17 United States (High Plains) and Canadian (Alberta) feedlots were retrospectively retrieved from a feedlot veterinary consulting and data-management service. Chronic cattle ("chronics," n = 52,886) were defined as those assigned to a designated chronic pen. Cattle records were evaluated using descriptive statistics. Chronicity rates varied across all feedlots (median 1.1%, range 0.1 to 5%). Across all feedlots, the top three discrete predominant diagnoses were respiratory (median 45.2%, range 19.1 to 99.1%), lameness (median 23.9%, range 0.1 to 50.5%), and bullers (median 2.7%, range 0 to 24.3%). Across all feedlots, the most common final disposition was shipped to slaughter at market weight (median 62%, range 20.1 to 94.1%). Some feedlots shipped (railed) chronics before reaching market weight (median 9.4%, range 0 to 49%). Mortality events consisted of unassisted (median 18.6%, range 5.7 to 37.5%) and euthanasia (median 3.1%, range 0 to 16%) mortalities. Increases in railed and respiratory cattle were seen over the study years, and there was variation in the distribution of respiratory, lameness, and buller Predominant Diagnosis Groups by feedlot arrival season. This is the first large-scale descriptive study of chronic cattle across multiple diagnosis groups, which establishes descriptive reference values that can be used for comparison to better understand chronic pen populations and welfare at similar feedlots.