Effects of grazing on grassland or wood-pasture, slaughtering age and ageing time on meat production and quality in Podolian young bulls

: Podolian cattle is an autochthonous breed well adapted to the harsh semi-arid environments of the Southern Italy regions; the extensive rearing system used for these indigenous animals is based on grazing on spontaneous pastures, such as grasslands or wood pastures These grazing systems respect animal welfare and enrich animal products with characteristics closely related to the feeding system and the farming environment. The aim of the present study was to characterize the nutritional value of a forage crop and a wood-pasture and to evaluate the effects of grazing by Podolian young bulls on the performances and meat quality in relation to the age at slaughter (14 or 18 months) and to the ageing time of meat (3, 9 or 14 days). The metabolizable energy and the gas production were greater in April and June for both pasture systems. Young bulls raised on the grassland showed greater slaughter weights (p < 0.05) as compared to those fed on the woodland system, at both the slaughtering ages. The Warner Bratzler Shear (WBS) force values for raw and cooked meat were not influenced by the pasture system but they significantly (p < 0.01) decreased in relation to the ageing time in all the groups. Ageing markedly (p < 0.05) increased the malondialdehyde (MDA) concentration from 3 to 14 days of storage, regardless of the pasture system and the slaughtering age. The n-6/n-3 polyunsaturated fatty acid ratio of meat was markedly lower in grassland animals, regardless of the age of slaughter. In conclusion, 18 months old grassland beef showed better performances and yield of meat cuts. Ageing for 9 days positively affected meat WBS without increasing MDA concentration.