Extensive Iberian pig production grazing systems Benito J. 1 , Albarrán A. 1 and García Casco J. M. 2 1Escuela de Ingenierías Agrarias, Universidad de Extremadura, Carretera de Cáceres sin, 06071 Badajoz, Spain. 2Asociación Española de Criadores de Cerdo Ibérico, CI San Francisco 51 1° D, 06300 Zafra (Badajoz), Spain. Abstract The Iberian native pig breed from the south west of the Iberian Peninsula is characterized by its full use of the natural meadowland resources of pastures and acorns. Its evolution has developed to make full adaptation to an extensive management system under unfavourable climatic conditions. Feeding in the late fattening phase, a long productive cycle under extensive management (with slaughter at over 15 months old), and the lipid characteristics of its meat have combined to enable the production of a high quality meat, especially for cured meat products: hams, fillet and shoulder of pork. The Iberian pig is a unique animal of the dehesa that has capacity for the transformation of feed to high value fat and muscle. The objective valuation of this quality and its consequences for commercial transactions between breeders and meat processors, and the application of a specific quality designation for these meat products, are two of the main challenges for this breed and its fundamental link with meadowland. At present, the Iberian pig is the most important agrarían production of the dehesa and it is exceptional in having recently shown increased prices for producers at a time when the profitability of cattle and sheep production has fallen. Key words: montanera, quality, dehesa, meat regulation, fat. Origin and distribution In many respects the Iberian pig breed can be regarded as probably the most successful of the native pigs whose breeding is restricted to particular geographic areas, not only in terms of the size of its population, but al so for commercial or economic reasons. This breed, the result of Sus scrofa mediterraneous evolution, which has an historical antecedent of African origin, is widespread in the whole southwest Iberian Peninsula, in the Spanish autonomous regions such as Extremadura (Cáceres and Badajoz), the west of Andalucía (Sevilla, Córdoba, Huelva, with important herds of pigs in Cádiz and Málaga), the south west of Castilla and León (mainly in Salamanca, with extensions in Zamora, Valladolid or Ávila), and Castilla - La Mancha (Toledo and Ciudad Real). In addition, its Portuguese version, known as Porco alentejano, whose origin and characteristics are similar to the Spanish one, is abundant in the whole Alentejo region, from Algarve (in the south) to Beira (in the north). For readers familiar with the environmental resources of the Iberian Peninsula, the peculiarities and distribution of fauna and flora in the different ecosystems provides the first clue to understanding the reasons for the success of this breed: the ecological area of the Iberian pig coincides with the large areas of meadowland of Spain and Portugal. Nevertheless, although the breed's traditional geographical distribution was valid until the middle of the 1990s, it is now undergoing serious changes. As a consequence, in areas where the Iberian pig was previously almost negligible (existing only thanks to some breeders who wanted to keep them for sentimental reasons), the numbers of Iberian pigs have now greatly increased. In areas where people raise mainly early maturating white pigs such as Barcelona, Lérida (both in Cataluña), Murcia, provinces of Castilla and León like Segovia, purchase of Iberian sows is now increasing as breeders want to participate in the production of Iberian pigs, while retaining their normal intensive production systems. This trend, instead of stopping, is still tending to increase, and now inc1udes some other Spanish regions such as Galicia and Aragón. Sustainable Grassland Productivity 635 Census and evolution When people talk about Iberian pigs, it is necessary to explain the changing circumstances that this breed has suffered, because the production systems which are really favourable have been underestimated. However, work and perseverance by some breeders, industrialists and authorities, have allowed, to a certain extent, restoration of the situation. Various historical references exist showing the connection between the Iberian pig and its environment, such as its presence in Montánchez and Trujillo's charters in XVI century, the regulations of Carlos V, etc., which confirm the old Iberian pig breeding and its use of environmental resources. The following paragraphs consider the events of the last 50-60 years. At the beginning of the twentieth century, the status of the Iberian pig was considered as being protected because its breeding and consumption were basic components of human diets across a large area of the peninsula. Then, at the beginning of the 1970s, several factors plunged the Iberian pig breed into a deep crisis. As a result, a there was a drastic reduction in its numbers, which put the breed's survival in danger. This disaster in the population led to a big loss in the previously abundant genetic variability. It is of interest to mention some of the economic, social and animal health factors that converged to cause the crisis. One aspect was the demand for other kinds of animal products, which caused a decrease in consumption and a reduction in the traditional family production of pigs for home slaughter. Moreover, at that time, having overcome the enormous nutritional deficiencies caused by the conflicts of the 1930s and 40s, there began several national and international campaigns, sometimes unfounded, against the consumption of meat with high fat content. The growing worry about health caused a change in meat quality objectives and the main objective at that time was reducing the amount of fat in meat products. This second aspect provoked a high selection process towards white breeds for intensive production. The proposed objective of decreasing the fat in Iberian pigs, and also increasing the growth rate and muscle yield, caused the beginning of crossbreeding out with foreign breeds, which had a leaner constitution; all of which contributed to an important fall in the amount of pure Iberian breeding stock. With this crossbreeding, people want to shorten the long productive cycle associated with the meadowland farming, thereby increasing their low economic profitability. From all of this crossbreeding that was tried out during these years, we keep one, made with the Duroc breed, even though more controlled and being aware of the current quality requirements. The animal health aspects related to the Iberian pig population crisis deserve a special mention. The most unfortunate chapter of this story occurred in 1960, when there was an outbreak of African Swine Fever (ASF) in Badajoz, a border town with Portugal. The later virus infection, and its rapid extension to the rest of the pig population, resulted in the total destruction of many herds and al so in a gradual change in breeders' customs, with very little exchange of breeding stock. This reduction stressed the population structure further and led to genetic isolation of some herds of pigs. Two further aspects contributed to the decline in Iberian pig breeding. One was the exodus of rural people during the 1950s-1970s, which affected the Andalusian, Castilian and Extremeños populations, with movements from their towns to the big urban Spanish centres that had important industrial developments (Madrid, Barcelona, País Vasco), as well as emigration to other European countries where there was a need for labour (Switzerland, Germany, France), and to Latin American countries with emerging economies (Argentina, Venezuela). The other aspect, and probably the most unfortunate one, was the transformation of thousands hectares of botanically diverse meadowland on farms to crops that were more profitable at that time (sown grass, vines, etc.) or for tree planting of species with a rapid growth rate (e.g. pine, eucalyptus). Thus the native trees, Quercus rotundifolia and Quercus suber, were extracted, the meadowlands were lost, and with them everything related to the traditional land-use systems, including the Iberian pigs. Authors who have given figures for this population fall have indicated that the numbers of female Iberian pigs decreased from more than half a million in the 1950s to 53,000 by 1982. From 1985 we have seen a re-emergence of the Iberian pig herds as a result of five basic effects. First, there was the important work done by breeders, veterinarians and animal health authorities from the various state and autonomous organizations, resulting in the gradual decrease of the effects of ASF. By 1995, this disease had been totally eradicated. Secondly, the greatly improved socio-economic conditions in Spain during in the last 30 years have increased the demand for quality food products, in spite of the higher market 636 Grassland Science in Europe, Vol. 11 price of such products. Iberian acorn ham is the one of the best examples of this trend. The third factor is related to the environmental concerns by some sections of the population, and the recognition that the meadowland is a unique ecosystem in the world. The meadowland is an example of how it is possible for an interaction between man and the environment, and provision of economic resources for the populations that settle in it being associated with an enormous biodiversity. Another element that has increased the Iberian pig value, and of its products, has been the recent accreditation of the beneficial dietary effects of unsaturated fats, compared with saturated fats. Olive oil and Iberian pig meat consumption have benefited from the return to a Mediterranean diet. As has been noted, many pig producers are replacing part of their female pigs by Iberian female pigs, or going directly into Iberian pig production and in its curing products. This has been in response to the progressive deterioration in the price for early maturing pig carcasses.