Evaluation of pre-slaughter losses of Italian heavy pigs

Abstract

A retrospective observational study evaluated the risk factors for pre-slaughter losses (i.e. animal deaths occurring during transport and lairage) and their economic impact in Italian heavy pigs (~160 kg bodyweight). Of the 3 344 730 pigs transported, 1780 (0.053%) died before slaughter, with most losses occurring during transport (56.6%). The estimated economic impact was of 424 000 €. The percentage of batches with at least one animal lost pre-slaughter increased during summer (P < 0.001). The proportion of pre-slaughter losses was higher when journey lasted more than 90 min (P < 0.001) and was positively correlated with transport duration (P < 0.01). Losses were higher (P < 0.01) in batches transported at low stocking densities (i.e. when heavier pigs were transported). Batches with lower slaughtering order (i.e. longer lairage time) had higher proportions of losses (P < 0.001). Logistic regression analysis showed that the odds of a given batch to have at least one animal lost pre-slaughter were 1.32 times higher for batches slaughtered in summer, 1.54 times higher if journey durations exceeded 90 min, 1.25 times higher for batches with low slaughtering order, and not significantly influenced by stocking density during transport.Additional keywords: economic impact, pig welfare, transport.The identification of critical points during transport and slaughtering procedures may significantly improve animal welfare during transport. In heavy pigs, long travel duration, low stocking density and overnight lairage resulted in increased animal losses. The routine collection and analysis of animal-loss data at slaughterhouses could reduce the economic impact of animal losses and be of help in improving future legislation on the protection of pigs during transport.

A Retrospective Study after 10 Years (2010–2019) of Meat Inspection Activity in a Domestic Swine Abattoir in Tuscany: The Slaughterhouse as an Epidemiological Observatory

“…Additionally, analyzing the data per year, summer was always the season with the highest number of deaths, although a statistically significant difference in comparison with the winter season was observed only for two years (2016–2017). No statistically significant difference was observed when applying the two seasons proposed by Nannoni et al [ 27 ]. Overall, the months with a significantly higher number of deaths were August, September, and December.…”

“…As regards the seasonal mortality, the higher rate observed in summer (astronomically defined) and in August, September, and December seems to confirm the sensitivity of pigs to thermal stress [ 27 , 30 , 48 , 52 , 53 ]. In fact, although the actual temperatures of the investigated years were not collected, the average temperature in August, September, and December in the North and Centre of Italy are outside the thermal neutral range for pigs (15–25 °C) [ 30 ].…”

“…Loading and unloading are particularly critical moments [ 41 ]; mixing up different groups of animals can also cause severe stress and induce aggressive behavior [ 46 , 47 ]. In addition, the loading density and time, the truck structure, the environmental temperatures, the lack of a fasting period before transport, and the duration of transport may influence the welfare [ 27 , 42 ].…”

“…The chi-square test (significance for p < 0.05) was used to evaluate differences between the years, seasons, months, and geographical origin (region and province of the conferring farm) in terms of deaths during transport and whole carcass condemnations and, due to the larger amount of data, only between the years for partial condemnations. As regards the seasonal trend, this was calculated both among the four astronomical seasons (starting dates: spring, 20 March; summer, 20 June; autumn, 22 September; winter, 21 December) and also according to Nannoni et al [ 27 ] (summer: from April to September; winter: from October to March). The analyses were conducted on proportions to correctly compare samples of varying sizes.…”

Identification of Possible Pre-Slaughter Indicators to Predict Stress and Meat Quality: A Study on Heavy Pigs

“…Therefore, there is a considerable lack of knowledge regarding the handling of smaller and larger pigs, which may react differently to pre-slaughter stressors. Lighter and heavier pigs are more susceptible to heat stress, especially during transport of long (between 8 and 24 h [1]) and short duration (90 min [15]), respectively.…”