Date Full Report Received06/08/2009
Date Abstract Report Received06/08/2009
Funded ByNational Pork Board
Marketing and transportation stress not only costs the industry due to fatigued, injured and dead pigs, but has a direct impact on the quality of pork delivered to the consumer. The loading process in particular has been reported to be the most stressful part of the whole marketing process due to the pigs having to navigate tight corners, narrow incline, temperature and climate changes, and movement from light to dark areas. By understanding basic big biology (that they move from dark to light areas, they will move better with another pig, that they do better walking up inclines that are less steep) we designed a state of the art loading gantry system that was constructed of an aluminum covered chute and measured 91.4 cm in width, 3.1 m in height, and 9 m in overall length, including a 7.9 m sloped section and two dual pivoting extension systems that allowed for proper positioning to both the barn and trailer. A cushioned bumper dock system was incorporated into the loading gantry design to completely eliminate gaps from the barn to the loading gantry. The flooring material consisted of metal coated with epoxy (designed to mimic the feel of concrete on the pigs feet) and had an inverted stair step design with cleats 2.5 cm in height and spaced 20.3 cm apart. The gantry slope was approximately 7 degrees to the bottom deck and 18 degrees to the upper deck of the trailer. The state of the art loading gantry system utilized an industrial rope lighting system designed to provide a soft, continuous light source that minimized shadowing. This state of the art loading gantry system was compared back to a traditional metal covered chute. This chute was 76.2 cm in width, 2.3 m in height, and 4.6 m in length, and used square stock (2.5 cm) metal cleats which were spaced 20.3 cm apart. The traditional chute included a flat pivot section on each end to accommodate the angle that the trailers were positioned relative to the finishing facility. The slope of the chute used to load the pigs onto the trailer was approximately 19 degrees to the bottom deck. The trailer included an internal ramp raised 23 degrees for access to the upper deck. One incandescent lamp fixture (60 watts) was placed at the entrance to the traditional chute.
Pigs loaded using the state of the art loading gantry system experienced fewer electric prods, slips, falls, vocalizations, and pile ups. The state of the art loading gantry system lowered total losses (total crippled + total stressed + total dead) in first pull pigs. The state of the art loading gantry system influenced several pork quality attributes. Loins taken from pigs from the first pull loaded with the state of the art loading gantry system had higher initial and 24 h pH and tended to have higher Japanese Color Score cut values, but lower loin L* values. The higher JCS cut values and lower L* values indicate a darker, redder color meat. Among loins collected from pigs loaded with the state of the art loading gantry system that came from the close out pull loins had higher 24 h pH and JCS rib values, but lower L* values. This investigation has provided data to support changes in loading system design that may ultimately lead to the improvement of performance, welfare, and pork quality.
Corresponding author: Anna Johnson E-mail Johnsona@iastate.edu