Evaluation of the sustainability of contrasted pig farming systems: the procedure, the evaluated systems and the evaluation tools

Review: The challenge to integrate Animal Welfare indicators into the Life Cycle Assessment

The transition to a more sustainable livestock sector represents one of the major challenges of our time. Life Cycle Assessment (LCA) is recognised as the gold standard methodology for assessing the environmental impact of farming systems. Simultaneously, animal welfare is a key component of livestock production and is intrinsically related to human and environmental well-being. To perform an overall on-farm sustainability assessment, it would be desirable to consider both the environmental impact and the welfare of the animals. The present work aimed to summarise and describe the methodologies adopted in peer-reviewed papers published to date, that combine animal welfare evaluation with LCA. Citations, retrieved from four bibliographical databases, were systematically evaluated in a multi-stage approach following the JBI and PRISMA scoping review guidelines. The searches identified 1 460 studies, of which only 24 were compliant with the inclusion criteria. The results highlighted how the environmental LCA was undertaken with a much more homogenous and standardised method than animal welfare assessment. When studies were grouped based on the type of animal welfare assessment performed: 16.7% used single welfare indicators, 45.8% multiple indicators, 8.3% applied existing validated protocols (i.e., TGI-200 and TGI-35L), 16.7% used non-validated protocols and 12.5% employed other methods. The papers were further classified with respect to the "5 Animal Welfare Domains Model": the most assessed domain was "environment" (90.5% of the papers%), followed by "health" (52.4%), "nutrition" (33.3%), "behavioural interactions" (28.6%) and "mental state" (9.5%). None of the studies assessed all the domains simultaneously. In addition, 66.7% of papers (n = 16) aggregated the animal welfare indicators into a final score. Within these, only four papers proposed to associate the animal welfare scores with the LCA functional unit. An overall sustainability score, calculated with several different approaches to summarise the information, was provided by 46% of the papers. In summary, despite the topic's relevance, to date, there is neither a consensus on the animal welfare assessment approach to be carried out (indicators selection and their aggregation) nor on the standardisation of an integrated animal welfare-LCA evaluation. The present review provides a basis for the development of common future guidelines to carry out a comprehensive, true-to-life and robust farm sustainability assessment.

Review: Quality of animal-source foods

This article critically reviews the current state of knowledge on the quality of animal-source foods according to animal production and food processing conditions, including consumer expectations-behaviours and the effects of consumption of animal-source foods on human health. Quality has been defined through seven core attributes: safety, commercial, sensory, nutritional, technological, convenience, and image. Image covers ethical, cultural and environmental dimensions associated with the origin of the food and the way it is produced and processed. This framework enabled to highlight the priorities given to the different quality attributes. It also helped to identify potential antagonisms and synergies among quality attributes, between production and processing stages, and among stakeholders. Primacy is essentially given to commercial quality attributes, especially for standard commodity animal-source foods. This primacy has strongly influenced genetic selection and farming practices in all livestock commodity chains and enabled substantial quantitative gains, although at the expense of other quality traits. Focal issues are the destructuration of chicken muscle that compromises sensory, nutritional and image quality attributes, and the fate of males in the egg and dairy sectors, which have heavily specialised their animals. Quality can be gained but can also be lost throughout the farm-to-fork continuum. Our review highlights critical factors and periods throughout animal production and food processing routes, such as on-farm practices, notably animal feeding, preslaughter and slaughter phases, food processing techniques, and food formulation. It also reveals on-farm and processing factors that create antagonisms among quality attributes, such as the castration of male pigs, the substitution of marine-source feed by plant-based feed in fish, and the use of sodium nitrite in meat processing. These antagonisms require scientific data to identify trade-offs among quality attributes and/or solutions to help overcome these tensions. However, there are also food products that value synergies between quality attributes and between production and processing phases, particularly Geographical Indications, such as for cheese and dry-cured ham. Human epidemiological studies have found associations between consumption of animal-source foods and increased or decreased risk for chronic non-communicable diseases. These associations have informed public health recommendations. However, they have not yet considered animal production and food processing conditions. A concerted and collaborative effort is needed from scientists working in animal science, food process engineering, consumer science, human nutrition and epidemiology in order to address this research gap. Avenues for research and main options for policy action are discussed.

A Systematic Mapping of Research on Sustainability Dimensions at Farm-level in Pig Production

We systematically mapped the scientific literature on the sustainability of pig production at farm-level. Sustainability was considered holistically, covering its economic, environmental, and social dimensions, each consisting of a broad range of different aspects that may contradict or reinforce each other. Literature published between January 2000 and March 2020 with a geographical focus on Europe, North America, Australia, and New Zealand was included. A standard template with predefined keywords was used to summarise aspects of each sustainability dimension covered in identified papers. We found that papers analysing environmental sustainability were more frequent than papers analysing economic or social sustainability. However, there are many different aspects within each dimension of sustainability, hampering comparisons between studies. In addition, each dimension of sustainability has many sides, making it difficult to compare different studies, and different dimensions and aspects may have complex interrelations. Our systematic literature review revealed that these interrelations are not well understood and that possible trade-offs or synergies between different aspects of sustainability dimensions remain unidentified. This systematic mapping of the current literature on farm-level sustainability in pig production can support a more informed discussion on knowledge gaps and help prioritise future research at farm-level to enhance sustainability in pig production.

Production parameters and pig production cost: temporal evolution 2010-2014

Background

The assessment of the cost of production and the relative weight of the different production parameters is very important in pig farming. The goals of the present work were 1) to describe reliable reference values for production parameters and pig production cost from 2010 to 2014, 2) to describe their temporal evolution and 3) to determine the influence of the pig company size on them. Between 61 and 107 pig production companies from Spain were included in this study from 2010 to 2014. These companies sent data on feed consumption, number of pig produced, expenses and census every month. Sip consultors SL standardized collected data and calculate cost and production parameters to obtain values comparables between the different pig production companies. The collected data each month were merged to obtain a yearly average value taking into account the pig production flow each month. A suitable statistical analysis was carried out to tackle the goals.

Results

The production performance has been continuously improving in the piglet production and fattening phase from 2010 to 2014. Thus, the number of piglets by sow and year will increase 0.5 pigs by year and the total feed conversion rate will decrease approximately 0.03 kg feed/kg gain by year in the future if the same tendency continues. However, feed price has been steadily increasing from 2010 to 2012 and decreasing afterwards and the total cost per kilogram produced has followed a similar pattern. This result highlights the relevance of the feed price in the final cost in spite of continuous improvement in production performance across years. Finally, pig company size affected most of the production parameters studied. Thus, the best technical parameters were obtained for companies with less than 5000 sows. However, the opposite tendency is observed for feed price where the highest value was observed for the smallest companies.

Conclusions

Pig production parameters have generally improved in the last five years but this improvement did not directly imply a reduction in pig production cost due to the high feed prices during the period 2010–2013.

Electronic supplementary material

The online version of this article (doi:10.1186/s40813-016-0027-0) contains supplementary material, which is available to authorized users.