Review: Towards the agroecological management of ruminants, pigs and poultry through the development of sustainable breeding programmes. II. Breeding strategies

Agroecology uses ecological processes and local resources rather than chemical inputs to develop productive and resilient livestock and crop production systems. In this context, breeding innovations are necessary to obtain animals that are both productive and adapted to a broad range of local contexts and diversity of systems. Breeding strategies to promote agroecological systems are similar for different animal species. However, current practices differ regarding the breeding of ruminants, pigs and poultry. Ruminant breeding is still an open system where farmers continue to choose their own breeds and strategies. Conversely, pig and poultry breeding is more or less the exclusive domain of international breeding companies which supply farmers with hybrid animals. Innovations in breeding strategies must therefore be adapted to the different species. In developed countries, reorienting current breeding programmes seems to be more effective than developing programmes dedicated to agroecological systems that will struggle to be really effective because of the small size of the populations currently concerned by such systems. Particular attention needs to be paid to determining the respective usefulness of cross-breeding v. straight breeding strategies of well-adapted local breeds. While cross-breeding may offer some immediate benefits in terms of improving certain traits that enable the animals to adapt well to local environmental conditions, it may be difficult to sustain these benefits in the longer term and could also induce an important loss of genetic diversity if the initial pure-bred populations are no longer produced. As well as supporting the value of within-breed diversity, we must preserve between-breed diversity in order to maintain numerous options for adaptation to a variety of production environments and contexts. This may involve specific public policies to maintain and characterize local breeds (in terms of both phenotypes and genotypes), which could be used more effectively if they benefited from the scientific and technical resources currently available for more common breeds. Last but not least, public policies need to enable improved information concerning the genetic resources and breeding tools available for the agroecological management of livestock production systems, and facilitate its assimilation by farmers and farm technicians

Effects of rearing system on performance, animal welfare and meat quality in two pig genotypes

Abstract The effects of an alternative rearing system (O) for growing-finishing pigs (sawdust-shave bedding with free outdoor access, 2.4 m²/pig) compared to a conventional (C) one (slatted floor, 0.65 m²/pig) were evaluated for performance, animal welfare and meat quality in two (Duroc or synthetic line crossbreds) genotypes. Trials were conducted in spring and winter, each involving one pen of 10 pigs / genotype / system (a total of 40 pigs / season). No significant interactions between rearing system and genotype were observed on any of the traits evaluated. On the whole, the O pigs spent 40% more time on exploratory activities, in particular towards the bedding, suggesting an improved animal welfare with the O system. Urine levels of cortisol and catecholamines in the O were similar with those in C pigs at 70kg. The O pigs exhibited a 6% increase in growth rate and were 5kg heavier at slaughter at the same age. Back fat depth and lean meat content, as well as plasma ACTH and cortisol, and urine cortisol and catecholamines levels at slaughter were not significantly affected by the rearing system. The O pigs exhibited similar pH 1 and pHu values, higher drip losses, but also higher intramuscular fat contents. The O system improved loin juiciness, but did not influence other eating quality traits

Changes in the relative thickness of individual subcutaneous adipose tissue layers in growing pigs

<p>Abstract</p> <p>Background</p> <p>The thickness of the subcutaneous fat layer is an important parameter at all stages of pig production. It is used to inform decisions on dietary requirements to optimize growth, in gilts to promote longevity and finally to assist in the calculation of payments to producers that allow for general adiposity. Currently for reasons of tradition and ease, total adipose thickness measurements are made at one or multiple sites although it has been long recognized that up to three well defined layers (outer (L1), middle (L2), and inner (L3)) may be present to make up the total. Various features and properties of these layers have been described. This paper examines the contribution of each layer to total adipose thickness at three time points and describes the change in thickness of each layer per unit change in body weight in normal growing pigs.</p> <p>Methods</p> <p>A group of nine pigs was examined using 14 MHz linear array transducer on three separate occasions. The average weight was 51, 94 and 124 kg for each successive scan. The time between scanning was approximately 4 weeks. The proportion of each layer to total thickness was modeled statistically with scan session as a variable and the change in absolute thickness of each layer per unit change in body weight was modeled in a random regression model.</p> <p>Results</p> <p>There was a significant change in ratios between scans for the middle and inner layers (<it>P </it>< 0.001). The significant changes were seen between the first and second, and between the first and final, scan sessions. The change in thickness per unit change in body weight was greatest for L2, followed by L1 and L3.</p> <p>Conclusion</p> <p>These results demonstrate that subcutaneous adipose layers grow at different rates relative to each other and to change in body weight and indicate that ultrasound can be used to track these differences.</p

Influence de la réduction de lapport en nutriments sur les performances et les impacts environnementaux de lengraissement des porcs au Brésil.

Abstract: Sustainable low-carbon pork production is a priority in most pig meat producing countries. In Brazil the feed supplied to the animals is rich in nutrients and their reduction remains questioned. The objective of this study was to evaluate the effect of reducing dietary nutrient content for fattening pigs on their performance and environmental impact. The study addressed the growing-finishing phase of pig production including feed production, animal housing and manure management. Forty gilts and 40 barrows were distributed in a randomized block design with two treatments and 10 replicates per treatment. The treatments consisted in two feeding strategies with in four feeding phases in each. In the standard (ST) strategy, feed was formulated with standard Brazilian recommendations. In the low nutrient (LN) strategy, requirements were adjusted by using the InraPorc® model. Performance and excretion data were used to calculate, through life cycle assessment (LCA), the carbon emissions and the potentials of acidification and eutrophication. The functional unit was the kg of body weight gain (BWG). Both feeding strategies led to similar growth performance, with ADG of 919 g/d and FCR of 2.68 kg/kg. Carcass and meat quality were also not affected by treatments. Carbon footprint was reduced in the LN strategy in comparison with ST (2.57 versus 2.67 kg CO2-eq./kg BWG). Similar effects were observed for acidification (57.2 versus 62.3 g SO2-eq./kg BWG) and eutrophication (17.2 versus 19.0 g PO4-eq./kg BWG). Results suggest that nutritional adjustment based on prediction models is a valuable alternative to standard formulation in Brazil, which allows to improve economic results and to reduce environmental burdens without affecting technical performance. Resumo: A produção sustentável de carne suína de baixo carbono é uma prioridade na maioria dos países produtores de carne de suíno. No Brasil, a alimentação fornecida aos animais é rica em nutrientes e sua redução permanece questionada. O objetivo deste estudo foi avaliar o efeito da redução do teor de nutrientes na dieta de suínos de engorda em seu desempenho e impacto ambiental. O estudo abordou a fase de crescimento e terminação da produção de suínos, incluindo a produção de rações, alojamento de animais e manejo de dejetos. Quarenta leitoas e 40 machos foram distribuídos em delineamento de blocos casualizados com dois tratamentos e dez repetições por tratamento. Os tratamentos consistiram em duas estratégias de alimentação com quatro fases de alimentação em cada. Na estratégia padrão (ST), o alimento foi formulado com recomendações brasileiras padrão. Na estratégia de baixo nutriente (LN), os requisitos foram ajustados usando o modelo InraPorc®. Os dados de desempenho e excreção foram utilizados para calcular, através da avaliação do ciclo de vida (ACV), as emissões de carbono e os potenciais de acidificação e eutrofização. A unidade funcional foi o kg de ganho de peso corporal (GP). Ambas as estratégias de alimentação levaram a um desempenho de crescimento semelhante, com um GMD de 919 g / dia e FCR de 2,68 kg / kg. A qualidade da carcaça e da carne também não foi afetada pelos tratamentos. A pegada de carbono foi reduzida na estratégia do LN em comparação com o ST (2,57 versus 2,67 kg CO2eq./kg BWG). Efeitos semelhantes foram observados para a acidificação (57,2 versus 62,3 g SO2-eq / kg de peso corporal) e eutrofização (17,2 versus 19,0 g PO4- eq / kg de peso corporal). Os resultados sugerem que o ajuste nutricional baseado em modelos de previsão é uma alternativa valiosa para a formulação padrão no Brasil, o que permite melhorar os resultados econômicos e reduzir a carga ambiental sem afetar o desempenho técnico

ProPIG - Organic pig health, welfare and environmental impact across Europe

Organic production is perceived by consumers as being superior in animal welfare and sustainability and the demand for organic pork products is slowly increasing. Within the past ten years a variety of husbandry and management systems have been developed across the EU, ranging from farms with pigs outdoors all year round using local breeds to farms with housed pigs having concrete outside runs and using conventional breeds (CorePIG, Rousing et al, 2011). So far, mainly clinical parameters have been used to describe the health situation on organic pig farms, identifying some key problems, such as weaning diarrhoea and piglet mortality. Organic pig production is - amongst others - characterised through a holistic approach based on the EU Regulation (EC) No 834/2007 and the IFOAM principles: ‘health, ecology, fairness and care’. This clearly states that health is more than absence of clinical symptoms and, the relation between animals and their environment is identified: ‘Health’ is defined as ‘the wholeness and integrity of living systems. It is not simply the absence of illness, but the maintenance of physical, mental, social and ecological well-being’ (IFOAM; 2006). Concepts of animal welfare include physical and mental welfare as well as the concept of naturalness (Fraser 2003), which is often interpreted as the ability to perform natural behaviour. Verhoog et al (2003) describe three main approaches within organic agriculture’s concept of nature and naturalness: the no-chemicals approach, the agro-ecology approach and the integrity approach. Applying those concepts to organic pig production can highlight potential conflicts: outdoor systems are perceived as the optimal housing system for pigs, as they allow natural behaviour such as rooting. However, this behaviour can cause damage to the grass cover and furthermore the manure fate in outdoor areas needs to be considered. A few studies on outdoor pig production have shown a clear N and P surplus and a high degree of distribution heterogeneity in outdoor areas, increasing the risk of N and P losses (Watson et al. 2003). Robust and competitive organic pig production needs to encompass low environmental impacts and good animal health and welfare. So far few studies have quantified both aspects in different pig husbandry systems. In addition, the theory that improving animal health and welfare reduces environmental impacts through decreased medicine use, improved growth rate and feed conversion efficiency has still to be verified. The aim of the CoreOrganic2 project ProPIG (2011-2014; carried out in eight European countries) is to examine the relationship between health, welfare and environmental impact. On-farm assessment protocols will be carried out on 75 farms in three pig husbandry systems (outdoor, partly outdoor, indoor with concrete outside run). Environmental impact will be assessed using both Life Cycle Assessment and calculations of nutrient balances at farm and outdoor area level. Animal health and welfare will be evaluated from animal based parameters including clinical and selected behavioural parameters. Results will be fed back and used by the farmers to decide farm specific goals and strategies to achieve these goals. As an outcome, all farms will create their individual health, welfare and environmental plan, which will be reviewed after one year to allow continuous development. This will provide the opportunity not only to investigate, but also improve the influence of organic pig farming systems on animal welfare and environmental impact. This fulfils the fourth IFOAM principle of care: ‘Organic Agriculture should be managed in a precautionary and responsible manner to protect the health and well-being of current and future generations and the environment’ (IFOAM, 2006)

Computer tomographic investigation of subcutaneous adipose tissue as an indicator of body composition

<p>Abstract</p> <p>Background</p> <p>Modern computer tomography (CT) equipment can be used to acquire whole-body data from large animals such as pigs in minutes or less. In some circumstances, computer assisted analysis of the resulting image data can identify and measure anatomical features. The thickness of subcutaneous adipose tissue at a specific site measured by ultrasound, is used in the pig industry to assess adiposity and inform management decisions that have an impact on reproduction, food conversion performance and sow longevity. The measurement site, called "P2", is used throughout the industry. We propose that CT can be used to measure subcutaneous adipose tissue thickness and identify novel measurement sites that can be used as predictors of general adiposity.</p> <p>Methods</p> <p>Growing pigs (<it>N </it>= 12), were each CT scanned on three occasions. From these data the total volume of adipose tissue was determined and expressed as a proportion of total volume (fat-index). A computer algorithm was used to determined 10,201 subcutaneous adipose thickness measurements in each pig for each scan. From these data, sites were selected where correlation with fat-index was optimal.</p> <p>Results</p> <p>Image analysis correctly identified the limits of the relevant tissues and automated measurements were successfully generated. Two sites on the animal were identified where there was optimal correlation with fat-index. The first of these was located 4 intercostal spaces cranial to the caudal extremity of the last rib, the other, a further 5 intercostal spaces cranially.</p> <p>Conclusion</p> <p>The approach to image analysis reported permits the creation of various maps showing adipose thickness or correlation of thickness with other variables by location on the surface of the pig. The method identified novel adipose thickness measurement positions that are superior (as predictors of adiposity) to the site which is in current use. A similar approach could be used in other situations to quantify potential links between subcutaneous adiposity and disease or production traits.</p