含不同比例莱芜猪血缘杂交猪胴体品质及 肉质特性的研究

摘 要： 以莱芜猪、3/4莱芜猪、1/2莱芜猪、1/4莱芜猪和大约克夏猪（共60头）为研究对象,在同样条件下饲养至90kg屠宰,研究比较不同比例莱芜猪血缘对肥育猪胴体品质和肉质特性的影响。结果表明：不同血缘结构的试验猪间在胴体重、胴体长、后腿比例和背膘厚方面存在显著的差异（P<0.05）;眼肌面积和瘦肉率方面则存在极显著的差异（P<0.01）,并且是随莱芜猪血缘含量的减少,其胴体长、后腿比例、眼肌面积和瘦肉率逐渐增高,而其背膘厚逐渐降低。在肉质特性方面,不同血缘结构的试验猪间肌肉的大理石纹、肉色、干物质和粗蛋白含量存在显著的差异（P<0.05）;而肌肉失水率、滴水损失及肌内脂肪含量存在极显著的差异（P<0.01）。在同样体重下,莱芜猪及其杂交猪与大约克夏猪相比,其肌肉具有鲜红的肉色、良好的持水性能和较丰富的肌内脂肪。研究结果提示：为兼顾产肉性能与肉质特性而进行的优质肉猪生产,莱芜猪有其独特的利用价值,其适宜的血缘比例应控制在1/4左右。Abstract: Sixty pigs, including pure Laiwu Black (LL), pure Large Yorkshire (YY), 1/2 Laiwu (Y♂×L♀), 3/4 Laiwu (L♂×YL♀) and 1/4 Laiwu (Y♂×YL♀), were housed in groups with the same diet until 90kg for slaughter. The objectives were to investigate the effects of graded proportions of Laiwu Black genes on carcass and meat quality performance. Results indicated that different consanguinity had significant effect on carcass weight, carcass length (CL), ham percentage (HP) and backfat thickness (BT) (P<0.05), and had highly significant effect on eye muscle area (EMA) and lean percentage (LP) (P<0.01). Furthermore, CL, HP, EMA and LP tended to increased gradually, but BT tended to decreased gradually as Laiwu Black genes decreased. For meat quality properties, different consanguinity had significant effect on meat color, marbling score, dry matter and crude protein content of muscles (P<0.05), and had highly significant effect on water loss, drip loss and intramuscular fat content of muscles (P<0.01). Compared with the muscle of Large Yorkshire, that of Laiwu Black and its crossbred pigs were bright red in meat color, high in water holding capacity and abundant in intramuscular fat. Results implied that to give attention to both quantity and quality, Laiwu Black surely has usable precious value in superior pig production. Commercial crossbred pigs should have about 1/4 of Laiwu Black genes.     

3个猪品种黑素皮质素受体1(MC1R)基因变异研究

利用测序、PCR-RFLP和PCR-SSCP等技术对杜洛克、长白、大白猪MC1R基因进行研究发现了5个多态位点。其中,668位点G→C突变发生在5′UTR,其余4个多态位点nt894insCC(894位点CC插入),1318C→T,1554G→A和1197G→A发生在编码区。nt894insCC导致编码蛋白过早终止。1318C→T,1554G→A和1197G→A突变分别导致a164Val,Ala243Thr和Asp124Asn氨基酸的改变。所有长白、大白猪个体在894位点均存在CC插入,其余多态位点基因型分别为668GG,1197AA,1318CC,1554GG。所有杜洛克个体在894位点均不存在CC插入,其余多态位点基因型分别为668CC,1197GG,1318TT,1554AA。所有突变位点无杂合子出现。由此可以推测,668G→C,1318C→T和1554G→A可能与杜洛克的红毛色存在相关,导致1197G→A突变无意义的894位点CC插入可能与长白、大白猪白毛色存在相关。     

改良大鼠子宫内膜异位症模型的建立及微血管密度观察

目的对皮下筋膜层与腹壁肌层之间移植自体子宫内膜制作的子宫内膜异位症（endometriosis,EMs）模型进行评估。方法取10只雌性未交配性成熟大鼠,术前雌激素诱导,手术开腹取右侧子宫,将自体子宫内膜种植于双侧皮下筋膜层与腹壁肌层之间,术后第29天取出异位组织,进行组织形态学观察,免疫组织化学染色观察微血管密度（Microvessel density,MVD）。结果异位内膜在腹壁内生长,呈隆起囊状小包块,内有黏液,具有正常子宫内膜基本组织结构。异位内膜中微血管密度较在位内膜和正常子宫内膜高。结论此手术方法建立的大鼠子宫内膜异位症模型异位内膜病理改变与EMs患者类似,可以作为子宫内膜异位研究的动物模型。