Risk factors identified on arrival associated with morbidity and mortality at a grain-fed veal facility: A prospective, single-cohort study

摘要

High levels of morbidity, mortality, and antimicrobialuse are common in the veal industry. For the sustainabilityof the industry, it is important to address thesechallenges and determine factors that can be used toimprove animal health and welfare. The objectivesof this prospective observational cohort study wereto describe the health status of calves on arrival ata grain-fed veal facility and determine characteristicsthat were associated with morbidity and mortality.On arrival, the calves were assessed for health abnormalities,weighed, measured for hip height and lengthfrom withers to lumbosacral junction, and had bloodcollected to determine serum total protein level. Bodymass index (BMI) was calculated using weight on arrivaldivided by the sum of the calf’s length from withersto lumbosacral junction and hip height. The calveswere observed for 77 d after arrival, during which theproducer was responsible for recording all antibiotictreatments and mortality. We built Cox proportionalhazard models for morbidity and mortality variables.We created 2 morbidity models: 1 for calves that weretreated <21 d after arrival at the facility, and 1 forcalves that were treated during the 11 wk at the facility.From January to December 2017, 998 calves wereevaluated on arrival at the veal rearing facility. A largeproportion (68%) were treated with antibiotics in thefirst 21 d after arrival. The only explanatory variablein the final <21 d morbidity model was BMI: calveswith a higher BMI had a lower hazard of being treatedfor disease in the first 21 d after arrival. A total of 872calves (87%) were treated at least once over the 11-wkhousing period. A calf arriving with a BMI >371.46g/cm or a serum total protein between 5.8 and 6.2 g/dL had a lower level of morbidity during the observationperiod. Over the 11-wk housing period, 74 calves(7.5%) died. Calves that arrived at the facility with afecal score of 2 or a rectal temperature between 38.9and 39.1°C had a higher hazard of dying; calves thathad a BMI of >371 g/cm were less likely to die thancalves that had a BMI <330 g/cm. These results pointto the importance of assessing calves on arrival at aveal facility as a measure of identifying those at highrisk for morbidity and mortality.