RESEARCH IN PIG BREEDING, 11, 2017 (1) ACORNS AND CHESTNUTS AS IMPORTANT COMMODITIES IN ORGANIC PIG FARMING Bělková J., Václavková E., Rozkot M., Kuchařová S. Institute of Animal Science, Prague Uhrineves, Czech Republic Abstract Recent years have seen an increasing trend toward organic pig farming within the Czech Republic and many other countries. One impetus for this development is probably a shifting orientation among consumers from product price to product quality accompanied by growing interest in organic quality meat. Another important factor is the effort to create more humane conditions for farmed animals and to meet welfare requirements. Last but not least, such farming methods are also more environmentally friendly and support transforming agriculture and food systems to sustainability. The essence of organic farming is a return to nature and historic tradition. For pigs, this means pasture farming systems based on collecting such foods as acorns and chestnuts. In some regions, these farming methods have been maintained as ancient traditions and are still used to this day. In many other places, including the Czech Republic, however, these methods represent a return to a forgotten tradition. We have decided to determine the nutritional value of chestnuts and acorns occurring in the local environment. This information is instrumental in optimizing feeding rations for pigs reared through alternative methods as well as evaluating the effects these feeds have on the quality of meat produced. Key Words: Acorns; chestnuts, pig nutrition, organic farming, nutritional value Domesticated pigs are bred around the world pastures. In Central Europe, year-round farming and comprise one of the most important areas of in sties began only with the introduction of agricultural production. In addition to highly improved crop rotation in the mid-19th century productive intensive farms, the number of (Muzikářová 2011). Extensive farming including extensive farming operations has recently begun pasturing of pigs was partially maintained, and to increase again, which is a welcome alternative today it is returning in the form of alternative for supporters of ecological agriculture and farms due to efforts to protect animals from abuse organic production as well as animal rights and maintain biodiversity as well as the economic activists. These farms use pasture systems which opportunity associates with increasing demand mark a return to historical farming practices and for meat produced naturally or of organic quality. more natural lives for pigs that are based on such Advantages to farming pigs through pasturing natural sources as collecting the likes of acorns are lower costs of entry and improved animal and chestnuts. health and welfare. In contrast, negative The wild boar (Sus scrofa) is a typical omnivore economic effects ensue from the lower fertility of without very rigorous food requirements and the breeds used and reduced weight gains due to which eats grass, tubers, seeds, carrion, roots, pastured animals’ genotypes, increased rubbish, insects, small vertebrates, and frequently thermoregulatory requirements, and greater also agricultural crops. While most of its diet activity. Within intensive farming, year-round (90%) consists of vegetative materials, it always confinement without the possibility to run about consumes at least one type of energy-rich plant and long-term breeding selection has caused pigs such as acorns, chestnuts, beechnuts, olives, or to lose their resistance to adverse environmental other crops (depending on its range) (Schley and effects while also diminishing their ability to Roper 2003). For this reason, it primarily prefers adapt to unfavorable conditions. Pasture farming, to live in mature deciduous or mixed forests. This therefore, uses autochthonous breeds, as these are lifestyle led to historical pig farming that involved hardier and accustomed to the given environment, pasturing in forests and later on designated and for most such breeds pasture farming has been 7 RESEARCH IN PIG BREEDING, 11, 2017 (1) maintained as an ancient tradition. Examples of As noted above, pasture fattening affects the such breeds can be seen in the Iberian pig in quality of meat and fat produced due to the feed Spain, the Alentejano pig in Portugal, the Cinta composition. The meat’s physical and Senese in Italy, and the Mangalica in Hungary. organoleptic properties change and its Such traditions have not been maintained in the composition are influenced substantially in terms Czech Republic, but such breeds as the native of fatty acids. Pigs fed with chestnuts and acorns Přeštice Black-Pied can be used for these produce fat and meat with significantly different purposes. The Přeštice Black-Pied is very fatty acids, in particular with increased oleic acid, adaptable, undemanding and capable to utilize which further affects sensory properties (Pugliese pasturing. et al., 2008). At the same time, technical When pasturing, feedstuffs composition and properties also change in the same manner such environmental conditions are substantially that the meat and fat is suitable for traditional reflected in the quality of the meat and fat long-term curing and drying. Nutritional produced. When acorns are used for feeding or properties also differ, of course, inasmuch as the finishing, this meat and fat is used to produce proportion of fatty acids changes to become specific products from the aforementioned advantageous for human nutrition from a breeds. The best known of these products is cardiovascular perspective (Fallola et al., 1998). certainly the Spanish ham jamón ibérico de Pugliese et al. (2009) reported that Cinta Senese bellota from black Iberian pigs (cerdo negra) boars fed with chestnuts and acorns had increased farmed in southern Spain in oak forests known as monounsaturated fatty acid content in fat in dehesas. During a period of 6 months (each comparison to animals fed with a common autumn and winter), pigs in this region consume commercial concentrate (chestnuts 46.9%, acorns approximately 6.5–9 kg (15–20 pounds) of acorns 47.76%, concentrate 44.78%), primarily due to (bellotas) per day with weight gains of up to 0.9 increased oleic acid levels (chestnuts 44.2%, kg/day (Mast Tree Network 2009). Pigs are acorns 44.91%, concentrate 42.05%, P<0.05). The similarly pastured in the New Forest region of group fed with chestnuts also had a higher southern England, where the practice is known as percentage of PUFA-n3 (1.18%) than did the two “pannage” and pigs feed mainly on acorns and remaining groups (1.06% and 1.03%, P<0.05). beechnuts for at least 60 days from the start of Similarly, Petron et al. (2004) found more oleic autumn. During pasturing, chestnuts are often acid and less stearic and palmitic acids in the used for fattening, as along with oaks chestnut meat of Iberian pigs fed with acorns. Although trees are the most common tree species in the the resulting product has higher fat content than pasture areas. In Spanish dehesa regions, the most does that of commonly reared pigs, it is healthier common oaks are Quercus ilex (evergreen oak) for consumers due to its high content of beneficial and Quercus suber (cork oak). In the Czech omega-3 fatty acids and oleic acid, which, among Republic, the most common oaks are Quercus other effects, positively influence cholesterol robur (English oak), Quercus petraea (sessile levels. These pigs are therefore sometimes oak), and Quercus rubra (northern red oak), and referred to as “olive trees on four hooves” for the most common chestnuts are Castanea sativa their positive health effects which are similar to (sweet chestnut) and Aesculus hippocastanum those of olive oil. (horse-chestnut, which is not technically a true Although the tradition of pasturing was not chestnut). preserved in the Czech Republic as it was in Today, fattening on pastures generally is southern European countries, approximately 50 utilized most frequently on the Iberian Peninsula years ago pasturing was commonplace. This is and in the Mediterranean region. A feature reflected in nutrient value tables for feedstuffs common to these systems is the use of local from 1965 (Čvančara 1965), which in addition to genotypes of mostly high-fat pigs fattened until grasses and tree leaves also included beechnuts, they have reached a relatively advanced age (14– chestnuts, and acorns as common feedstuffs. In 18 months) and high slaughter body weight of the following decades, agriculture in the Czech 120–140 kg. At slaughter, they have a high Republic was intensified and so pasturing pigs percentage of body fat and a considerable level of became less common and farming systems and intramuscular fat (Nunes 2007). feedstuffs gradually changed. Information on 8 RESEARCH IN PIG BREEDING, 11, 2017 (1) alternative feeds also disappeared from the Results and Discussion literature due to efforts to unify agricultural production. Although we are now returning to The results of the analysis are presented in older traditions, we do not have sufficient Table 1. Considering their high starch content information properly to introduce them. Today’s (47.72%), horse-chestnuts can be classified as a farmers lack experience with alternative pig high-carbohydrate feed, which is also in farming as well as guidelines and expert accordance with their high sucrose content information on feeds, including their use and (12.65%). However, horse-chestnuts also had nutritional values. For this reason, we have relatively high content of nitrogen substances decided to update this information and determine (6.58%) in comparison to acorns. Acorns also had the nutritional value of horse-chestnuts and starch as a dominant component, and so these, acorns commonly occurring in the Czech too, constitute a high-carbohydrate feed, albeit landscape and evaluate the effects these feeds with substantially greater fiber content. These have on the quality of meat produced. values were compared with data found in the literature (i.e., with the nutrient value tables for Material and Methods feedstuffs from Čvančara 1965), which are presented in Table 2.