The Effect of Feeding High Fiber and Fat Diet on Pig Meat Quality

The application of strategic finishing diets to reduce the muscle glycogen content at slaughter is considered a method to improve pork meat quality. The objective of this study was to assess the effects of feeding pigs with high fat and low digestible carbohydrate diets in the late finishing period (last 29 days) on meat quality. Four dietary treatments were applied: 1) a control diet (C: 67.2% corn, 15.5% soybean meal and 15.0% hard wheat), 2) a high fat and fiber diet (HFF: 38.0% corn, 17.9% soybean meal, 15.0% hard wheat, 20.0% oat hulls and 6.9% fat), 3) a blend of 50-50% C and HFF diets (MIX), and 4) pigs were fed the C diet for 11 days and transferred to the HFF diet for 11 days after 7 days diet transition (C/HFF). A total of 160 pigs (119.2 ± 6.2 kg), balanced by gender (barrows and gilts), were raised in 20 pens of 8 pigs each (5 pens per treatment). At the end of the finishing period, pigs were weighed and fastened between 16 and 19 h preslaughter. Whole blood lactate level was assessed at exsanguination using a hand-held Lactate Scout Analyzer (EKF Diagnostic GmbH, Magdeburg, Germany). On the slaughter day, hot carcass weight was recorded and pH was measured at 1 h post-mortem in the longissimus (LM) and semimembranous (SM) muscles. Meat quality was also assessed at 24 h post-mortem by measuring pHu in the LM, SM and adductor muscles, color (Minolta L*, a* and b*) in the LM and SM muscle, and EZ-drip loss in the LM. Analyses were performed using the mixed procedure of SAS, with the pen as the experimental unit, using treatment, sex and their interactions in the model. Results neither indicated differences between treatments nor an interactive effect (P>0.05) between sex and treatment for final live weight and any of the post-mortem measured variables. These results may either indicate the inefficiency of the applied dietary treatments for meat quality improvement or, based on the low exsanguination blood lactate values (mean and confidence interval of 5.2 mmol/L [5.8-6.7 mmol/L], respectively), that the stress imposed on pigs preslaughter in this study might not have been sufficiently high to result in meat quality variation.