Effects of Plane of Nutrition on Growth Performance and Meat Quality Traits in Finishing Pigs

Abstract

The present study was performed to investigate the effects of the plane of nutrition on growth performance and meat quality traits, especially marbling and PSE(pale, soft, and exudative), in finishing pigs. One hundred and four barrows and 102 gilts born to Yorkshire×Landrace dams and Duroc sires were randomly allocated to 16 pens at approximately 80-kg body weight, with 13 animals housed per pen except for two pens. Each eight pens received a diet containing either 3.4 Mcal ME/kg and 0.98% total lysine(high plane) or 3.1 Mcal ME/kg and 0.81% total lysine(medium plane). All animals were slaughtered at approximately 112 kg BW on an average, after which the Longissimus muscle(LM) was analyzed physicochemically. The ADG, ADFI, gain:feed as well as marbling score did not differ between the two dietary groups, whereas backfat thickness was greater in the high-plane group than in the medium-plane group(24.1 vs. 22.5 mm P<0.05). No LM exhibited PSE, i.e. L*(lightness)>50, pH<6.0 and drip loss>5.0%, nor were these PSE-related variables influenced by the dietary treatment. Contents of crude protein and fat in LM did not differ between the two dietary groups. In conclusion, the present results suggest that growth performance and the occurrence of the PSE or ‘watery’ carcass are not influenced significantly by increasing the plane of nutrition in finishing pigs when the finisher is adequate nutritionally for supporting maximal lean growth. However, increasing the plane of nutrition is likely to result in an increase in fat deposition.