Production performance of pigs reared in different systems and fed increased energy content diets with or without green alfalfa
The objective of this study was to determine the effects of various feeding and housing systems on fattening performance, slaughter value and biochemical serum parameters in growing-finishing pigs. The experimental material comprised 90 growing-finishing pigs, divided into six groups of 15 animals that were diverse in terms of rearing (with or without free access to outdoor runs) and feeding systems (fed increased metabolizable energy (ME) content diets with or without green alfalfa). Different feeding regimes and rearing systems had no significant effects on most fattening results and the carcass traits of the pigs except for daily water and diet intake and feed/gain ratio. Daily water intake was lower in pigs fed complete diets plus green alfalfa forage. Low-density lipoprotein (LDL) cholesterol concentrations were statistically lower in the blood serum of Groups 3 and 6 than in Groups 2 and 4. High-density lipoprotein (HDL) cholesterol levels were significantly higher in the serum of Group 6, compared with other groups. Group 3 had significantly higher triglycerides levels compared with Groups 1, 2, 4, 5 and 6. Taking into consideration all these dependencies, it could be assumed that feeding regime and rearing with access to outdoor runs might improve not only blood lipid profile, but also the dietetic value of pork. It seems that feeding a complete diet with increased ME, plus green alfalfa forage and rearing indoors with free access to outdoor runs, gave the best results.
Keywords: Carcass quality, finishing system, lipids, pig nutrition, production system