Plant extracts in swine nutrition: Effects on some hematochemical parameters and sensory characteristics

There is an increasing public interest in the use of plant extracts in livestock feed. The objective of this study was to investigate the effects of inclusion of oregano (Origanum vulgare L) and chestnut wood (Castanea sativa) extract in pig diets, on some blood parameters, and chemical and sensory characteristics of the meat pork. Ninety Suffolk hybrids pigs were randomly divided into 6 groups (3 indoor and 3 outdoor; 15 animals/group) and, after the adaptation period, both indoor and outdoor pigs were assigned to one of the following iso-nitrogenous and iso-energetic diets: a) control, a commercial pellet diet (16.0% CP, 4.3% CF, 1.0% Lysine produced by Nuovo Molino, in Bastia Umbra, PG); b) control with 0.2% oregano essential oil; c) control with 0.2% oregano + 0.2% natural extract of chestnut wood. Diets were administered for 190 d until slaughter. Blood samples were taken at the beginning (s 1), after 120 (s 2) and at the end of the trial (s 3) to check the health status of animals by some minerals and hematochemical determinations (Ca, P, Zn, Cu, Mg, Fe, total protein, beta-hydroxibutyrate, free fatty acids, tryglicerids, cholesterol, LDLcholesterol) measured with an automatic analyzer (Hitachi 74); whereas the chemical characteristics and sensory quality of the pork were investigated, the first, on a mincemeat separately prepared from carcass (n. 3 animals) of each diet group and on derived matured salami, the second only on the derived matured salami. In conclusion, the diet integrated with plants extracts didn’t interfere with the animal health status or the minerals and hematochemical blood parameters investigated. However, the chemical parameters of the salami showed statistically significant differences especially as regards to the content of lipids and cholesterol, lower in outdoor pigs respectively for 20% and 40%. By contrast, the “consumer test” used to assess whether the consumer perceives sensory differences on the final products showed that the salami made from indoor pigs were significantly more appreciated by consumers (P0,05), regardless of the type of the diet followed by the animal. Then is possible concluded that the consumer “choice” not coincide with the healthy characteristics of meat.