Effects Of Various Levels Of Dietary Digestible Energy On Meat Quality Of CRP Complete Set Line's Commercial Hogs

The commercial hogs were selected from China Rongchang Pig (CRP) complete set line to study the effects of different diets' digestible energy level on performance and meat quality characteristics in finishing period. The results may offer some useful data for improving the pork quality by change the digestible energy level of diet, promoting the further selection and generalization of CRP complete set line.Feeding experiment and slaughter experiment were involved in the study. A single factor trial design was applied to the feeding experiment. Thirty six commercial hogs of CRP complete set line with initial average weight about 50kg were selected as the research object, which were divided into three diets' digestible energy level groups, each group containing three repeat and every repeat containing four pigs. This experiment was divided into two stages, the early finishing period(50-80kg) and the late finishing period (80-120kg). When the average weight of a repeat was close to slaughter weight, one pig of each repeat and each stage were selected to slaughter. Pigs with similar average weight and fed the same diet were selected to substitute the pigs slaughtered at the early finishing period. The results are as follows:(1) In the stage of 50-120kg , as the DE increase, daily gain has no significant difference (P>0.05); the feed intake in the 15.00MJ/kg control decreased obviously(0.010.05), but embody a rise trend; in the latter finishing period, the average back fat thick in the pigs that fed 15.00MJ/kg of DE are decreased significantly (P<0.01), but lean meat rate increased (0.050.05).(3) In the early finishing period, as the DE increase, except the marbling score, meat quality characteristics has no significant difference in other controls (P>0.05), the marbling score has a increase trend as the DE rising, 15.00MJ/kg of DE is highest(0.010.05).(4) From the index of muscle histology, in the latter finishing period, the muscle fiber area of semimembranosus in the pigs that fed 14.20MJ/Kg of DE is higher than pigs fed 13.00MJ/kg (0.010.05), they are all have a parabola shape change in different groups.(5) From the muscles of nutritional compositions, the muscles of nutritional compositions for the rest index has no significant difference among other controls (P>0.05) in the total finishing period, except that the contents of phosphonium in the pigs fed 13.00MJ/Kg of DE are lower than pigs fed 14.20MJ/kg and 15.00MJ/kg in the early finishing period(0.010.05). palmitoleic acid contents of the group added 2.00% soybean oil is higher than that added 5.43% soybean oil(0.05