Growth performance of local pig breeds – analytical review in the project TREASURE

<p>evaluate performance and growth potential of local pig breeds involved in H2020 project TREASURE (www.treasure.kis.si), data on average daily gain (ADG) was collected from the literature. Average growth rates reported for local pig breeds are generally lower than those of modern, selected breeds used in intensive farming. In the postnatal phase (lactation), ADG of local pig breeds is comparable with values of modern breeds (217±47 g/day); however it should be noted that lactation is longer (47.2±9.9 days) and birthweight lower (1.2±0.2 kg). The reported ADG in the growing phase (<30 kg) is somewhat lower compared to modern pigs (336±89 g/day), whereas fattening phases are characterised by considerably lower ADG (449-567 g/day depending on phase), but also by big heterogeneity (spanning from 85-1085 g/day), in line with different systems and feeding levels. Typically Iberico and Alentejano pigs have smaller ADG in early than late fattening which corroborates with their typical production system, i.e. restricted (recría) in early and ad libitum feeding in late fattening (montanera). However, in other local pig breeds similar or higher ADG in early than late fattening has been observed, implying restricted feeding in the later phases. As shown for several local pig breeds, relatively high ADG can be attained (≈1000 g/day) but leading also to substantial fat deposition. As growth is directly related to energy and nutrient supply, data on average daily feed intake (ADFI) was analysed and showed that reported ADFI roughly matched the expected/theoretical values in growing and early fattening phase, whereas ADFI was lower than expected in the late fattening phases. With ad libitum feeding high ADFI could be observed (late fattening ≈6 kg/pig/day) denoting high intake capacity of these non-selected breeds, a trait which seems to be reduced in modern breeds selected for lean growth. The survey (over 200 references) revealed great variability in terms of the availability and quality of information. A big part of collected studies simulated practical conditions of the production systems used, and only a small part of them allows a rough estimation of growth potential (and consequently infer nutritional requirements) which is important for developing and optimising the production systems for sustainable use of local pig breeds in agricultural production.