甘孜藏猪与合作猪SLA-DQA基因的群体遗传研究

对甘孜藏猪和合作猪SLA-DQA基因的第1和第2内含子部分序列以及完整的第2外显子进行了PCR-RFLP分析,结果表明:经EcoRⅠ酶切后,BB基因型频率(0.5537)分别高于AB型(0.3719)和AA型(0.0744); B为优势等位基因(0.7397).经AluⅠ酶切后,MM基因型频率(0.4380)分别高于MN型(0.3637)和NN型(0.1983);M为优势等位基因(0.6198).2品种中Alu I酶切基因型在合作猪中未达到Hardy-Weinberg平衡,且群体间M、N的基因频率和NN基因型频率差异分别达极显著(P＜0.01)和显著水平(P＜0.05).共鉴别了9种组合基因型,甘孜藏猪和合作猪分别为6和8种组合基因型, BBMM、BBNN组合基因型频率在两群体间差异显著(P＜0.05).两酶切位点均表现为中度多态,AluⅠ位点多态信息含量均高于EcoRⅠ位点,合作猪杂合性高于甘孜藏猪,两群体间的遗传距离为0.0389.     

用于人工血管的功能聚氨酯的迟发型超敏反应研究

聚氨酯原料如二异氰酸酯的皮肤致敏性已有大量报道,而聚氨酯材料本身的致敏研究的报道却很少。采用豚鼠最大剂量实验(ISO 10993-10)研究了3种用于人工血管的聚氨酯材料的迟发型超敏反应。PCUL2为赖氨酸扩链的聚碳酸酯聚氨酯,PCUL2-PO和PCUL2-PN分别为接枝聚乙二醇二缩水甘油醚以及接枝聚乙二醇二胺的梳形聚氨酯。3种材料均为多孔材料,且含有可反应的官能团,便于进一步接枝生物分子以提高血管的原位内皮化。测试组为(70±2)℃浸提(24±2)h的生理盐水浸提液(0.1 g/mL),生理盐水为阴性对照组,二硝基氯苯为阳性对照组。结果显示,3种受试材料致敏率很低(PCUL2-PO∶2/12;其余1/12)。3种聚氨酯的迟发型超敏反应的结果均为阴性,值得进一步进行体内研究。     

Quinoxaline-2-carboxylic acid in pigs: criteria to distinguish between the illegal use of carbadox and environmental contamination

Carbadox cannot be used in food-producing animals within the European Union following the adoption of Commission Regulation EC 2788/98/EC. Monitoring of the longest remaining residue—quinoxaline-2-carboxylic acid (QCA)—is the most effective way of enforcing the prohibition on its use. The study was under taken to determine if QCA could be passed from pig to pig following the exposure of unmedicated animals to housing that had previously contained medicated animals. Drug-withdrawal studies were also carried out on medicated animals. Distinction between treated animals and those exposed to QCA might be required by competent national authorities to determine whether a positive result for QCA in tissue is truly 'violative'. Comparison of the ratio concentrations of QCA in tissues and body fluids was made to determine if they could be used as criteria for discrimination between illegally treated animals and environmental contamination.     

青海八眉猪及其杂交猪肉挥发性成分分析

通过固相微萃取和气相色谱-质谱联用仪对青海八眉原种、二元长八、三元约长八及杜长大(对照)猪肉的挥发性风味成分进行检测分析。结果表明:八眉原种猪肉中挥发性风味化合物种类繁多、成分复杂,相对含量最高,且各风味成分以醛类物质为主;八眉原种、二元长八、三元约长八猪肉中壬醛(清香气味)、癸醛(甜香和柑橘香)、2,4-癸二烯醛(油脂香)、十二醛(皂香、柑橘香)、十四醛(脂肪香)、十六醛(花和蜡的弱香气)等醛类物质较杜长大猪肉丰富;1-辛醇(油脂香味、橘柑和玫瑰香味)、1-辛烯-3-醇(蘑菇香、青香、蔬菜香)、2-庚醇(淡芳香、脂肪香)等醇类物质分别在八眉原种、二元长八、三元约长八猪肉中有不同程度检出,3组猪肉的醇类物质种类及相对含量也高于杜长大猪肉;同时,十二烷酸(月桂油香)、十四碳酸(微弱的蜡香和乳香)、苯酚类(甜香)等化合物的相互作用叠加使八眉原种猪及其杂交猪肉形成独特风味,与杜长大猪相比肉质细腻、味道鲜美、风味醇香浓郁、肉品质量上乘。     

Degradation and physicochemical changes of barley and pea fibre along the gastrointestinal tract of pigs

The degradation of barley and pea fibres along the gastrointestinal tract (GIT) of pigs and its relation to changes in some of their physicochemical properties were investigated. Ileal and caecal digesta containing pea cotyledon fibre showed the highest (P < 0.05) swelling (33.1–36.7 ml g^?1 DM) and water retention capacity measured by centrifugation (17.9–21.2 g g^?1 DM) and by osmotic pressure (9.0–9.1 g g^?1 DM). The particle size of barley hull did not change along the GIT (160–207 µm), whereas that of pea cotyledon and pea hull was drastically reduced in faeces (62–65 µm) compared with the ileum and caecum (198–415 µm). The digestibility of non‐starch polysaccharides (NSP) was lowest for barley hull in the ileum (5% of intake), caecum (0% of intake) and faeces (26% of intake). The digestibility of NSP was highest for pea cotyledon fibre and dehulled barley in the proximal hindgut and for pea cotyledon fibre in faeces (96% of intake for pea cotyledon vs 74–82% of intake for dehulled barley and pea hull). In conclusion, hydration properties and particle size add valuable information when describing the fermentation of fibres in the GIT. However, they cannot be used alone as indicators of the extent of fermentation of different fibres. The results also suggested that the fibre source and the organisation and lignification of the cell walls lead to different fermentation processes along the GIT of pigs. © 2001 Society of Chemical Industry     

不同生长月龄下有机山黑猪背最长肌肉营养成分和食用品质的分析比较研究

以有机山黑猪为研究对象,分析其在不同生长月龄下的背最长肌肉营养成分及食用品质,以最终确定其最佳屠宰月龄。结果表明:月龄对水分、肌内脂肪、pH值、肉色、嫩度、滴水损失率、熟肉率均有显著(P<0.05)或极显著(P<0.01)影响;随着月龄的不断增长,山黑猪背最长肌肉水分含量逐渐降低,在7月龄最高为74.55%;蛋白质含量差异不显著(P>0.05),在8月龄最高为19.56%,其平均值为18.63%;肌内脂肪含量呈现递增趋势,有极显著(P<0.01)的影响,在10月龄最高为5.24%;有机山黑猪宰杀后45min,在4个不同生长月龄下肌肉亮度L1*平均值为44.26、肌肉红度a1*平均值为7.49,嫩度(剪切力)平均值为57.05N。结果表明:有机山黑猪肉色红润富有光泽、蛋白质及矿物质含量丰富、肌内脂肪含量适中且分布均匀等,具有肉质优良的宝贵特性,最终确定最佳屠宰月龄为8月龄。     

Food intake and live growth performance of pigs measured automatically and continuously from 25 to 115 kg live weight

Continuous automatic measurement and electronic recording provided data for individual pig live weight and food intake on a daily basis for a total of 74 pigs representing three commercially available crossbred types of mixed genetic origin, which were kept under commercial farming conditions to determine practical expectations for food intake and performance characteristics over the whole of the growth range from 25 to 115 kg live weight. The pig types were named as ‘Landrace’ type, ‘Pietrain’ type and ‘Meishan’ type, having been chosen to represent ‘lean’, ‘meaty’ and ‘fatty’ types. The pigs were fed ad libitum and serially slaughtered in groups at 32, 42, 63, 82 and 112 kg live weight (W). Results are presented in the order of pig type as above. Daily live weight gains at 80 kg live weight were 0.93, 0.94 and 0.91 kg day^?1 and at 100 kg were 1.04, 0.81 and 0.75 kg day^?1. Food intake curves differed with respect to both position and shape, with ‘Pietrain’ type pigs showing a lower increase with increasing live weight. Significant differences were found in the levels of fatness, as measured by P2 backfat depth, of the three pig types across the weight range examined (P < 0.001), in order of fatness ‘Pietrain’ type < ‘Landrace’ type < ‘Meishan’ type. Copyright © 2003 Society of Chemical Industry     

A comparison of the nutrient digestibility of Desi and Kabuli chickpeas fed to swine

An experiment was conducted to compare the nutritional composition of 16 varieties of chickpeas (Kabuli and Desi) and to determine their nutrient digestibility for swine using the mobile nylon bag technique. The average crude protein content of the Kabuli chickpeas (226 g kg^?1) was lower than that of the Desi chickpeas (235 g kg^?1). Desi chickpeas were higher in acid detergent fibre (145 versus 50 g kg^?1) and neutral detergent fibre (264 versus 181 g kg^?1) than Kabuli chickpeas. Digestibility coefficients for dry matter (83.1 versus 72.5%), gross energy (83.5 versus 74.8%) and crude protein (83.7 versus 79.4%) were higher for Kabuli chickpeas than for Desi chickpeas. Based on chemical analysis and nutrient digestibility, Kabuli chickpeas would appear to have greater potential as a protein and energy source for use in swine rations than Desi chickpeas. © 2002 Society of Chemical Industry