The Research Of Guanzhong Black Pig Performance And Yorkshire Pigs Hybrid Performance

Guanzhong Black Pig (GBP) is one of the Shaanxi local best varieties pigs. GBP are mainly fed in Xianyang, Xingping, Zhouzhi, Wugong, Yangling, etc. in Shaanxi province. GBP is famous for the high ability of enduring crude feed, disease resistance, good fertility performance, wonderful meat quality and other characteristics. It is not only an important raw material for pig meat production, but also the excellent maternal for goods lean pig. This study was conducted on the comparison of growth performance for the age of two, four, and six-month of Guanzhong Black Pig (GBP) and Yorkshire xGuanzhong Black Pig (YG) in Shaanxi Animal Husbandry CO., Ltd. The YG is hybridized combination with GBP as a female parent and with White pig as a male parent. Around30kg with the similar birth conditions,40GBP and20YG were selected for comparison for the fattening test. Six and four with the average weight92kg GBP and average weight90kg YG, respectively which were in the fattening period, were selected for the slaughter tests. The study focused on analysis of carcass and meat quality. The slaughtered muscle samples were further taken to lab for studying intramuscular fatty acids, intramuscular amino acids, and muscle fiber diameter and distribution density. The results showed in four perspectives.1、Growth and Development Performance:The body weight, body length, and circumference of YG at four and six months were42.7kg,90.8cm,92.2cm and82.9kg,112.2cm,112.2cm respectively. The heterosis rate of body weitht at four-month age was3.26%, and rates of circumference of chest both four-month and six-month age were4.71%and2.89%. However, the heterosis rates of body length and circumference of chest at four-month age as well as at six-month were negative, which all presented near-0.5%.2、Finishing performance:The finishing performance of YG was significantly higher than GBP. The average daily weight, feed conversion ratio for YG was591.60g and3.35:1, Compared with GBP, increase17.57%and14.33%;.respectively. Fattening period of YG was longer than that of GBP. The average gaining weight for YG in100days was60.44kg, while average weight of GBP63.97kg in130days. Results showed that the fattening speed of YG is higher than of GBP with less forage consumption.3、Carcass quality:The dressing-out percentage and lean meat percentage of GBP is74.61%and48.96%, respectively, which were not significantly different from YG (P>0.05). The GBP’s fat thickness is37.46mm, and fat percentage and suet percentage are33.96%,5.98%respectively, which were higher than that YG (P<0.05). The area of YG eye muscle is26.86cm2and hind legs ratio is27.71%. Both are higher than GBP. It indicated that capacity of fat deposition of YG is lower than that of GBP.4、Meat quality:(1) Meat Quality Traits:The marbling of GBP was3.75, which was significantly higher than the YG (P<0.05). The cooked meat percentage of GBP is higher (P<0.05) water loss percentage is lower (P<0.05) than YG The cooked meat rate and shear forces of GBP are7.18%and7.9%, respectively higher than YG (P>0.05). It indicated that the cooking loss of GBP is low and muscle is more solid.(2) For the fatty acid, saturated fatty acid of the GBP is41.44%(P>0.05), with higher (P<0.05) monounsaturated and lower (P<0.05) polyunsaturated fatty acids compared with the YG.(3) The proportions of total amino acids, flavor amino acids, proportion of essential amino acids in total amino acids for GBP were higher than YG with the non-significant difference (P>0.05). The proportion of flavor amino acid over the total amino acid is slightly higher (P>0.05). However, the content of four amino acids, which are threonine, alanine, glutamic acid and lysine, for GBP are higher than YG The four amino acids also play key roles in flavor of the meat of role.(4) For GBP, the muscle fiber diameter for GBP and YG are53.25and59.78um, respectively. The longissimus muscle fiber for GBP is thinner than that of YG (P>0.05). In addition, distribution of muscle fibers is loose and number for unit area is small. GBP has compact muscle fibers and in a good bundle.Overall, the growing and finishing pig performance for YG was significantly better than GBP. The meat quality for YG is worse than GBP but better than that of purebred white pig.