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31.
国内外猪胴体分级标准体系的现状与发展趋势 总被引:8,自引:0,他引:8
文中从探索建立适合我国国情的猪胴体分级体系,实现优质优价,促进我国商品猪品质提高的角度出发,较系统的概括了各国猪胴体分级标准的发展历史、现状及未来的发展方向。并且,根据我国的胴体分级现状提出了一些具体设想。 相似文献
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Almudena Soriano Rafael Quiles Cristina Mariscal Antonia García Ruiz 《Journal of the science of food and agriculture》2005,85(11):1914-1924
This study demonstrates that improvements in animal line selection by breeding enterprises exert a strong effect on carcass traits, meat quality and sensory characteristics of Serrano dry‐cured ham. A total of 461 pigs from the offspring of a Duroc (DU) × Landrace (LD) sow mated with two DU boars and a DU × Large White (LW) boar from three breeding enterprises were evaluated. The two DU terminal sires were significantly different (P < 0.05) in carcass conformation, backfat thickness, ham and loin yields, raw ham traits, myoglobin concentration and total pigments formed during the curing process; in addition, the two lines provided different percentages of hams (54 vs 91%) with sufficient subcutaneous fat and weight to manufacture dry‐cured Serrano hams using a slow ripening process (11 months). The DU × LW sire had the best carcass and ham traits from an economic standpoint and obtained highest scores for sensory characteristics of Serrano ham evaluated by a trained panel test; furthermore, this line provided 84% of total hams suitable for manufacturing Serrano hams by a slow process. When the sex effect was analysed, carcass and ham traits of females were more favourable, but females presented a higher incidence of pale, soft and exudative (PSE) meat and a lower percentage of hams with sufficient subcutaneous fat and weight to produce Serrano hams using a slow ripening process (61% for females and 91% for castrates). On the other hand, castrates provided Serrano hams cured by a slow procedure with better organoleptic characteristics than females. Right and left hams were similar. Copyright © 2005 Society of Chemical Industry 相似文献
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管道无损检测与评价技术 总被引:15,自引:0,他引:15
陈积懋 《石油化工设备技术》1997,18(1):59-62,58
为适应国内石油化工企业大量管道检测维护的急需,介绍了国际上有关管道在线无损检测、运行监视及泄漏检测的新技术、新设备和其应用情况与发展动态 相似文献
37.
Patrycja Witek Magorzata Grzesiak Marek Koziorowski Maria Slomczynska Katarzyna Knapczyk-Stwora 《International journal of molecular sciences》2022,23(5)
In this paper, we investigated the effects of neonatal exposure to methoxychlor (MXC), a synthetic organochlorine used as an insecticide with estrogenic, antiestrogenic, and antiandrogenic activities on ovarian follicles of adult pigs. Piglets were injected with MXC (20 μg/kg body weight) or corn oil (controls) from postnatal Day 1 to Day 10 (n = 5 per group). Then, mRNA expression, protein abundance and immunolocalization of growth and differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15), anti-Müllerian hormone (AMH) and cognate receptors (ACVR1, BMPR1A, BMPR1B, TGFBR1, BMPR2, and AMHR2), as well as FSH receptor (FSHR) were examined in preantral and small antral ovarian follicles of sexually mature gilts. The plasma AMH and FSH levels were also assessed. In preantral follicles, neonatal exposure to MXC increased GDF9, BMPR1B, TGFBR1, and BMPR2 mRNAs, while the levels of AMH and BMP15 mRNAs decreased. In addition, MXC also decreased BMP15 and BMPR1B protein abundance. Regarding small antral follicles, neonatal exposure to MXC upregulated mRNAs for BMPR1B, BMPR2, and AMHR2 and downregulated mRNAs for AMH, BMPR1A, and FSHR. MXC decreased the protein abundance of AMH, and all examined receptors in small antral follicles. GDF9 and BMP15 were immunolocalized in oocytes and granulosa cells of preantral follicles of control and treated ovaries. All analyzed receptors were detected in the oocytes and granulosa cells of preantral follicles, and in the granulosa and theca cells of small antral follicles. The exception, however, was FSHR, which was detected only in the granulosa cells of small antral follicles. In addition, MXC decreased the plasma AMH and FSH concentrations. In conclusion, the present study may indicate long-term effects of neonatal MXC exposure on GDF9, BMP15, AMH, and FSH signaling in ovaries of adult pigs. However, the MXC effects varied at different stages of follicular development. It seems that neonatal MXC exposure may result in accelerated initial recruitment of ovarian follicles and impaired cyclic recruitment of antral follicles. 相似文献
38.
Richard Howey Melvyn Quan Nicholas J. Savill Louise Matthews S?ren Alexandersen Mark Woolhouse 《Journal of the Royal Society Interface》2009,6(39):835-847
This paper investigates the early viral dynamics of foot-and-mouth disease (FMD) within infected pigs. Using an existing within-host model, we investigate whether individual variation can be explained by the effect of the initial dose of FMD virus. To do this, we consider the experimental data on the concentration of FMD virus genomes in the blood (viral load). In this experiment, 12 pigs were inoculated with one of three different doses of FMD virus: low; medium; or high. Measurements of the viral load were recorded over a time course of approximately 11 days for every 8 hours. The model is a set of deterministic differential equations with the following variables: viral load; virus in the interstitial space; and the proportion of epithelial cells available for infection, infected and uninfected. The model was fitted to the data for each animal individually and also simultaneously over all animals varying only the initial dose. We show that the general trend in the data can be explained by varying only the initial dose. The higher the initial dose the earlier the development of a detectable viral load. 相似文献
39.
周兴 《陕西科技大学学报》1994,(3)
针对猪皮纳帕服装革在国内外市场特别畅销受欢迎的发展趋势,旨在利用四川改良猪皮,采用国内化工材料,探讨生产具有天然粒纹,粒面细纹,清晰,光滑,车身丰满柔软而富有弹性。革身紧实而有适度的延伸性的高档猪皮纳帕服装革的工艺技术问题。根据多年的生产实践经验,将目前生产猪皮纳帕服装革的有关工艺技术问题进行初步探讨,需要在工艺技术上着重研究讨论的要点可以概括为:多步脱脂;多次膨胀且加强臀部处理,在复探中加入少量的助剂;脱灰完全;采用复合酶制剂(胰酶和蛋白酶),软化;无机酸,有机酸相结合的大浸酸且过夜平衡州值;助禁,准制中期加65”助剂后再碱化,注重复效,中和,加脂;轻涂饰,突出真皮感。 相似文献
40.
冯立志 《武汉工业学院学报》1994,(2)
选择体重65千克左右的杜洛克×大约克×长白杂种肥育猪180头,随机分配到三个饲粮营养水平,在炎热环境(白天平均温度27.82℃)饲养。结果表明,在炎热环境条件下,采用含3.2兆卡消化能/千克、16%粗蛋白、0.79%赖氨酸的饲粮饲养,可取得较好的生产性能和经济效益。 相似文献