Survey on pre-slaughter handling and skin damages on pig carcasses

Various stages during pre-slaughter handling, such transportation, lairage, and stress immediately before slaughter can negatively affect animals welfare and quality of carcasses. Rough practices at loading and unloading and inappropriate driving style of trucks and pigs may lead to serious skin damages. They represent a relevant economic losses, especially if are located on the most valuable cuts such as hams, loins and shoulders. In order to study the relationship between pre-slaughter handling and skin damages, a survey was carried out from January to June 2014 at one abattoir located in the Lombardia region. Data were collected from 1680 heavy pigs delivered from one farm to the slaughterhouse in 12 batches, each containing 140 subjects. Double trailer lorries with three hydraulic deck were used. At unloading of each deck, vocalizations, slips, falls, overlapping, balking and reversal were recorded. Resting duration and time requested to drive pigs to the stunning cage were measured. During this latter procedure, the same behavioural occurrences considered at the unloading were also recorded. Before evisceration, skin damages on regions of ham, loin, shoulder and head of each carcass were assessed by one trained inspector assigning for each region a score from 1 (absent) to 5 (serious). Score’s averages were found higher on carcasses of pigs transported into the trailer with respect to those transported into the lorry. Scores were affected by deck of the lorry, the upper showing the higher score. Behavioural occurrences, resting time and driving showed weak relationships with the damage scores. Probably, the handling carried out by the staff of slaughterhouse could be responsible of this result. This research highlights that some stages before and during transport could be more involved in skin damages than handling at the slaughterhouse. However, additional research is necessary to understand the role of pre-slaughter handling on the presence of skin damages on pig carcasses. Acknowledgments The Authors thanks for assistance the Quality Assurance staff of the abattoir. This research was supported by Regione Lombardia, Programma di Sviluppo Rurale 2007-2013, Misura 124.