Extensive Rearing Systems in Poultry Production: The Right Chicken for the Right Farming System. A Review of Twenty Years of Scientific Research in Perugia University, Italy

Abstract

The demand for poultry meat, being cheaper than red meat, will drive worldwide production of this product. Accordingly, an increase in production up to 16% is expected in 2025, most of which will occur in developing countries. Most poultry meat production is realized with intensive production systems, and extensive rearing systems (ERS) of poultry (organic, free-range, and low-input) represent only a small portion of poultry production in the EU (about 5%). However, there is an increasing interest in such rearing systems to maintain the good image of product and environmental sustainability, improved animal welfare, and meat quality with an annual trend of growth of about 10%. The aims of this work were to summarize the activities and the viewpoint of the researchers of the Department of Agricultural, Food, and Environmental Science of the University of Perugia (Italy). One of the most important goals of the research unit was the challenge of identifying the best poultry genotypes for ERS, which are important not only for the food industry but also for the improvement of human nutrition. Only the definition of the best genotypes adapted to ERS through the measurement of a wide panel of traits—genetic, physiologic, and behavior—and not only relying on daily weight gain will allow us to achieve this goal.

Soybean vs. Pea Bean in the Diet of Medium-Growing Broiler Chickens Raised under Semi-Intensive Conditions of Inner Mediterranean Areas: Growth Performance and Environmental Impact

“…Furthermore, a negative correlation between birds’ BW and active behaviours is also reported [ 30 ]. Regarding the physical activity, under the same farm and feeding conditions, medium- and slow-growing birds have a more active behaviour and higher adaptability to the natural environment compared to fast-growing genotypes [ 30 , 32 ]. This can explain the observed BW values being lower than those reported by commercial information on the selected genotypes [ 33 ].…”

The Assessment of a Multifactorial Score for the Adaptability Evaluation of Six Poultry Genotypes to the Organic System

“…The choice of suitable genotypes for the organic system is still an open question, and currently, the DWG is considered the main aspect to be considered. This approach paradoxically allows the use of FG genotypes submitted to specific rearing strategies (feed restriction, use of female chickens) to reduce the DWG [8]. It is well known that FG chickens reach the commercial weight in 35-42 days, which corresponds to roughly half the time requested by organic system regulations in Europe (81 days).…”

“…According to the above-mentioned findings, the use of outdoor areas by the chickens depends on DWG, which affects the kinetic characteristics of birds, but it also relies on the innate behavior expressed by the chicken (i.e., exploratory attitude, use of outdoor space, etc.). Thus, considering that the organic system provides 4 m 2 /chicken of outdoor space, not all poultry genotypes are suitable to fully exploit outdoor areas, and therefore, the productive potential (grazing as a feed supplement, improvement of the immune system, and meat quality) of this system [8].…”

Biomolecules, Fatty Acids, Meat Quality, and Growth Performance of Slow-Growing Chickens in an Organic Raising System

“…Chickens raised in OR have a high nutritional value in terms of protein, total collagen, and total omega-3 polyunsaturated fatty acid (n-3 PUFA) contents in meat [ 1 , 5 , 6 , 7 ]. However, the breeds suitable for OR need to be tolerant, resilient, adaptable, capable of utilizing quality balanced feed [ 8 , 9 , 10 ], and incur a low cost of production. Therefore, not all breeds are adaptable, but the slow-growing chickens seem to be suitable for the OR.…”