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This experiment assessed the effects of different quality and quantity of handling and quality of the holding yard environment on the productivity and physiological parameters indicative of stress in beef cattle. One-hundred-and-forty-four steers were given one of three human handling and yarding experiences on six occasions during a 12-month grazing period post-weaning (backgrounding): Good handling/yarding, Poor handling/yarding and Minimal handling/yarding. At the end of this phase the cattle were lot-fed for 78 days, with no handling/yarding treatments imposed, before being transported for commercial slaughter. Temperament was assessed by flight speed (FS) and a fear of humans (FOH) test, which measured the proximity to a stimulus person (ZA), the closest approach to the person (CA) and the amount the cattle moved around the test arena (TT). Mid-way through backgrounding, the Minimal treatment group was heavier than the Good, which was heavier than the Poor (mean weights 207, 201 and 194 kg, respectively; P = 0.05; LSD = 5.4), but by the end of backgrounding there was no difference between treatments and treatment did not affect liveweight during lot-feeding. At the end of backgrounding, plasma cortisol levels were significantly lower (P < 0.001) in the Good treatment group compared to the Poor and Minimal groups but at the end of lot-feeding there was no significant difference between the groups. Treatment affected plasma non-esterified fatty acid levels in backgrounding (P = 0.060) and lot-feeding (P = 0.046) with levels being higher in the Minimal than the Good and Poor groups (backgrounding: 0.52, 0.44 and 0.47 nmol/L, respectively; SE 0.02; lot-feeding: 0.46, 0.41 and 0.41 mmol/L, respectively; LSD = 0.05). Significant weak to moderate (r-value |
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