Economic losses related to the handling of pigs are well known throughout the industry (Tarrant, 1989). Handling effects on pig stress are complicated and few studies have quantified stress responses in common handling situations. In times of stress, the HPA (hypothalamic pituitaryadrena axis) axis is activated and glucocorticoids are released into the blood of the pig. Stress also causes changes in measures of the immune system (McGlone et al., 1993; Morrow-Tesch et al., 1994; Hicks et al., 1998; Salak-Johnson and McGlone, 2007). Alongside endocrine and immune responses to stress, stressed animals may undergo physiological changes such as increased heart and respiration rates that lead to an increase in body core temperature. Heart rate can be determined by use of telemetry to obtain undisturbed responses within experimental groups (Von Borell, 2001; Von Borell et al., 2007; Marchant-Forde et al., 2003a,b). The main hypothesis for this study was that when pigs are exposed to a novel environment they would have a higher heart rate and an overall stress response compared with those pigs that were habitualized with the environment. We also sought to determine if minimal training to remove novelty would reduce the stress experience for pigs destined for transport to slaughter. The ultimate goal is to reduce or eliminate stress-induced problems with pig losses during transportation and handling. Ten test subject pigs were selected per treatment. The first (trained) group was trained to navigate a course including a ramp. Testing was daily for seven days. Once training was completed, the trained and control (naïve) groups were exposed to a fixed course, the course and ramp (both up and down) while heart rates, time, handling difficulty, and blood were collected to determine the innate responses. It was concluded that heart rates of trained pigs were reduced significantly compared to naïve pigs travelling the same course. Both handling ease and handling time were significantly improved for the trained pigs compared to naïve pigs. Blood immune measures indicated reduced stress among trained pigs that had lower neutrophil numbers and lower total and average phagocytosis compared with naïve pigs. This study demonstrated that the exposure of pigs to a novel environment clearly causes a mild physiological response. Alleys and ramps do not inherently stress pigs, but rather novel experiences cause handling problems and a stress response and minimal training can reduce the stress experience for the pig.

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