Date Published: March 7, 2018
Publisher: Public Library of Science
Author(s): Mikael Frisk, Annie Jonsson, Stefan Sellman, Patrik Flisberg, Mikael Rönnqvist, Uno Wennergren, Mauro Villarini.
Each year, more than three million animals are transported from farms to abattoirs in Sweden. Animal transport is related to economic and environmental costs and a negative impact on animal welfare. Time and the number of pick-up stops between farms and abattoirs are two key parameters for animal welfare. Both are highly dependent on efficient and qualitative transportation planning, which may be difficult if done manually. We have examined the benefits of using route optimization in cattle transportation planning. To simulate the effects of various planning time windows and transportation time regulations and number of pick-up stops along each route, we have used data that represent one year of cattle transport. Our optimization model is a development of a model used in forestry transport that solves a general pick-up and delivery vehicle routing problem. The objective is to minimize transportation costs. We have shown that the length of the planning time window has a significant impact on the animal transport time, the total driving time and the total distance driven; these parameters that will not only affect animal welfare but also affect the economy and environment in the pre-slaughter logistic chain. In addition, we have shown that changes in animal transportation regulations, such as minimizing the number of allowed pick-up stops on each route or minimizing animal transportation time, will have positive effects on animal welfare measured in transportation hours and number of pick-up stops. However, this leads to an increase in working time and driven distances, leading to higher transportation costs for the transport and negative environmental impact.
Meat production has increased rapidly around the world in the past decades. This increase has had a major impact on the environment, animal welfare and global trade [1–3]. In Sweden the meat industry produces 133 100 tons of beef, 233 500 tons of pig meat and 5 100 tons of sheep and lamb meat per year , representing more than three million animal transports from farms to abattoirs per year. Transportation and handling are essential factors in the pre-slaughter production chain, playing an important role in animal welfare, meat quality and the risk of disease transmission . The pre-slaughter logistics chain comprises the transport operations and includes scheduling, management and control of animals transported from farms to slaughterhouse [5–7]. As described in Ljungberg et al. , animals are often collected from many farms. The logistic process include potentially stressful factors such as road conditions, climate, traffic conditions, number of pick-up farms, transportation time, and distance and queuing at abattoir. The factors expose the animals to various stimuli such as increased human contact, transportation, unfamiliar environments, food and water deprivation, social structure changes and climate changes that may lead to fear, dehydration, hunger, increased physical activity, fatigue and injury .
In the analysis we compare key figures in animal transportation related to animal transport time, distance and number of pick up stops in each route for six scenarios. The base scenario is the first of six that uses real 2008 data on cattle transports to the five largest abattoirs in Sweden. The data includes daily information about the amount of cattle that have been transported from a specific farm to a specific abattoir. We denote each date, farm and abattoir combination as a transport occasion. For example, if the data reports that fifteen cattle were transported from farm X to abattoir Y on January 1, 2008, we have a transport occasion. Five simulated scenarios are defined from the base scenario. These scenarios are formed using different combinations of two transport constraints: maximum number of pick-up stops along each route and maximum animal transportation time. Both are directly associated to animal welfare. All scenarios must include all transport occasions. That is, the fifteen cattle in the example must be transported from farm X to abattoir Y in one transport occasion in each scenario.
We have further developed a pre-slaughter transport route optimization model combined with a large dataset of information covering one year of cattle transportation to five Swedish slaughterhouses. Transportation distance, working time, transportation work and number of farm stops along each route have significant impact on animal welfare.
Unlike today’s manual planning, we have developed and tested a computerized route optimization model for animal transportation capable of pointing out measures that substantially improve animal welfare with reduced transportation times and number of stops. We have shown that changes in regulations, such as minimizing the number of allowed stops along each route or reducing animal transportation time, will have positive effects on animal welfare. Further, this will result in increased working times and driving distances, leading to higher transportation costs and a negative environmental impact. Deciding which alternative is the most desirable in each case is difficult, but can be supported by the route optimization model that offers the possibility of testing different alternatives beforehand.