Effects Of CMH On Growth Performance, Carcass Composition, Meat Quality And Approach To The Mechanism Of The Effects On Finishing Pigs

This study was conducted to evaluated the effect of dietary Cretine Monohydrate(CMH) on growth performance, carcass composition, meat quality of finishing pigs and it effects mechanism have been inquired.48 pigs (Duroc X Landrace X Yorkshine ternary crossed pigs) averaging 70kg in initial body weight were sorted by weight, gender and ancestry in a randomized complete block design and allotted to one of two dietary treatments, each group was replicated three times with eight pigs per replicate. Pigs were allotted to consume feed and water on ad libitum basis. The groups received the same basal diet (maize-soybean meal diet), supplemented with 0, 2500 ppm CMH respectively.The total experiment period was thirty-seven days, included seven preliminary trial days and thirtyformal trial days. By the end of the raising test period, weights were obtained from every pig, and feed intake was recorded prior to slaughter to calculate average daily gain(ADG), average daily feed intake(ADFI) and feed efficiency(F/G).Twelve pigs from each treatment were selected based on similar live weight (finial weight were 100 kg) to be slaughtered. Feed was withheld for 24 h prior to slaughter. Blood samples were collected at the time of slaughter to determine serum creatinine levels. Serum was separated and frozen(-30℃)until analyzed. Muscle samples from each pig were collected for color spectrophotometry, ultimate PH, the drip loss and laboratory analysis. At the same time, the skeletal muscles (Longissmus dorsi, Semimembranosus muscle, Semitenolinosus, Quadriceps femoris and biceps femoris) were separated from the carcass of the pigs to investigate the response of different muscles to CMH.The results of supplementing finishing pigs with CMH raise the daily gain (ADG) 2.87%(P>0.05), but did not affect ADFI, or F/G during the 37-day treatment period.The results of slaughter trial indicated that supplementing CMH in finshing pigs raised the eye muscle area by 9.12%(P<0.01), longissmus dorsi ratio raised 11.94%(P<0.01), biceps femoris ratio raised2.26(P>0.05); but did not affect carcass composition, the results of feeding CMH showed the increase of dissected lean ratio by 2.28%(P>0.05), decreased the dissected fat ratio by 5.44% (P>0.05), average backfat decreased 3.87%(P>0.05) and leaf fat weight decreased 1.37%(P>0.05).The slaughter trial also showed that CMH increase meat quality. Percentages drip loss of longissimus and semimembransus at 24 h postmortem decreased 27.69%(P<0.05) and 31.42%(P<0.05) respectively; meat color spectrophotometry suggested feeding CMH improve the meat color by 8.12%(P>0.05) and 12.92%(P>0.05) of the longissimus and semimembransus at postmortem, and it was consistent with the myoglobin content of this trial test; the ultimate PH at postmortem of the semimembransus increased 3.58%(P<0.05), but it seemed have a little effect on the longissimus.The muscle sample analysis indicated: adding CMH increased the inosinic acid (IMP) content by 29.44%(P<0.05) , the creatinine content increased 22.58%(P<0.05); the analysis of collagen showed that feeding CMH decreased the collagen content by 10.99%(P<0.05); CMH also made intramuscle fat content increased 34.15%(P<0.05), the moisture decreased 3.18%(P<0.05); it also found thar there was no difference in the content of DNA between the control and test groups, but adding CMH increased the RNA content and RNA/DNA ratio by23.91%(P<0.01) and 30.18%(P<0.01) respectively; it was found that supplementing CMH decreased the content of lactic of longissimus and semimembransus by 3.15%(P>0.05) and 4.93(P<0.05) respectively, and glycogen showed an increase trend of longissimus and semimembransus by 8.61%(P<0.05) and 9.61%(P<0.05) respectively; in addition, the analysis of the activity of CK showed CMH increases the skeletal muscle CK activity by 8.69%(P<0.05).The serum sample analysis indicated that CMH increased the activity of CK by 18.45%(P<0.01), but had no effect on the serum creatinine and other data.All o...