Effects Of Protein Sources In Rations And Cysteamnie On Production Performance And Meat Quality In Finishing Swine

With the improvement of quality of life, more attention had been paid for dietaryquality, especially for food flavor. Conversely, food quality was increasingly poor inreality including pork quality. It was a challenging subject for researchers that how toimprove the pork quality by means of nutritional regulation and control. Effects of proteinsources in rations and addition of cysteamine on production performance and meat qualityin finishing swine in the paper, and two experiments were conducted, experiment 1 andexperiment 2 respectively.Experiment 1: Effects of protein sources in rations on production performanceand meat quality in finishing swine. Eighty D×L×Y barrows and Eighty D×L×Y gilts(average 70±3.6 kg) were assigned into 16 pens with 10 a pen and 5 barrows and 5 giltsat random to investigate the effects of protein sources in rations on production performanceand meat quality in finishing swine in experiment 1. Experiment 1 adopted 4×4completely random design. To conduct the experiment 1, four types of rations weredesigned which were isoenergy and isonitrogen, mixture group, rapeseed meal group,cottonseed meal group and soybean meal group. The major difference between them wasthat different protein sources were included in each group, with soybean meal, rapeseedmeal and cottonseed meal were contained in the mixture group, soybean meal, rapeseedmeal and cottonseed meal were the main protein source in the soybean meal group,rapeseed meal group and cottonseed meal group respectively. After feeding for 40 days, 1barrow and 1 gilt chosen from each pen were slaughted in order to determine the carcassquality and meat flavor. Results showed that mixture protein source in ration would bemore favourable for finishing swine in ADG and F/G but not ADFI. There were little effectof different protein sources in rations on carcass traits and meat quality, but the content ofIMP in longissimus muscle was significantly influenced by them(P<0.05 )and the optimumprotein was cottonseed meal. Meanwhile, effects of protein sources in rations on thecontent of free Ser, Pro and tissue Cys, Met in longissimus muscle was detected(P<0.05).The content of free Ser in cottonseed meal group and soybean meal group weresignificantly higher than mixture group and rapeseed meal group, and the content of freePro was significantly higher than the other group. No effect of different protein sources inrations on fatty acid profile of IMF in longissimus muscle were found (P>0.05) . Theresults also showed that significant effect of protein sources in rations on meat flavor was detected, and the optium protein source in experiment 1 was cottonseed meal, whosearoma score and total flavor score were the best of all.Experiment 2: Effects of cysteamine on production performance and meatquality in finishing swine. Eighty D×L×Y barrows and Eighty D×L×Y gilts (average57.38±4.45 kg) were assigned into 16 pens with 10 a pen and 4 barrows and 6 gilts atrandom to investigate the effects of adding cysteamine (CS) on production performanceand meat quality in finishing swine in experiment 2. Experiment 2 also adopted 4×4completely random design. The basic diet was the control diet in eaperiment 1. Fourtreatments were control group with blank addition, treatment group 1 with adding CS for40 days, treatment group 2 with adding high-cysteamine(28% CS + 1. 5% V_C + 1. 5% V_E)from 1^th to 20^th day and adding CS(28%) from 21^th to 40^th day, and treatment group 3 withadding high-cysteamine from 1^th to 30^th day and adding CS from 31^th to 40^th day, and bothof the addition level was 200 g/t. After feeding 40 days, 1 barrow and 1 gilt chosen fromeach pen were slaughted in order to determine the carcass quality and meat flavor. Resultsshowed that cysteamine played an active role in improving the production performance offinishing swine, and ADG in three treatment groups were increased 5.6%, 5.1% and 6.3%respectively in contrast to control group. The tissue specificity was found in investigatingthe effect of cysteamine on carcass traits in finishing swine. The results also showed therewas a tendency to elevate the water-holding capacity due to the addition of cysteamine,and longissimus muscle area was significantly increased by the addition of cysteamine(P<0.05) .But cysteamine had no influence on pH value, meat colour, marbling, IMF andso on (P>0.05) . Meanwhile, cysteamine also had no influence on the content of IMP andamino acids in longissimus muscles (P>0.05) , further it had no influence on meat flavor,which could be concluded by the scoring results of the taste panel.In a word, we found that meat quality especially meat flavor could be regulated andcontrolled by the protein sources in rations and effects of different addition forms and waysof cysteamine on production performance and the normal indice of meat quality infinishing swine were detected when the effects of protein sources in rations and cysteamineon production performance and meat quality in finishing swine were determined.