Effects of dietary vitamin E on muscle vitamin E and fatty acid content in Aohan fine-wool sheep

Background

Increasing the polyunsaturated fatty acid (PUFA) content and decreasing the saturated fatty acid (SFA) content of mutton can help to improve its nutritional value for consumers. Several laboratories have evaluated the effects of vitamin E on the fatty acid (FA) composition of muscle in sheep. However, little information is available on wool sheep, even though wool sheep breeds are an important source of mutton, especially in northern China where sheep are extensively farmed. The present study was designed to address the effects of vitamin E on muscle FA composition in male Aohan fine-wool sheep.

Methods

Forty-two male Aohan fine-wool lambs (5 mo old) with similar initial body weight were randomly divided into seven groups and fed diets supplemented with 0 (control group), 20, 100, 200, 1,000, 2,000, or 2,400 IU/sheep/d vitamin E for 12 mo. Three lambs from each group were slaughtered to measure vitamin E and FA content in the longissimus lumborum (LL) and gluteus medius (GM) muscles.

Results

Vitamin E concentrations in the LL and GM increased significantly after 12 mo of vitamin E supplementation (P < 0.05). However, this increase did not occur in a dose-dependent manner because the muscle vitamin E concentration was highest in the 200 IU/sheep/d group. Dietary vitamin E supplementation also caused a significant reduction in SFA content and an increase in monounsaturated FA (MUFA) content in the LL and GM (P < 0.05). All six doses of vitamin E significantly increased cis9 trans11-conjugated linoleic acid (c9t11-CLA) content in the LL compared with the control group (P < 0.05).

Conclusions

Dietary supplementation with vitamin E increased muscle vitamin E content and improved the nutritional value of mutton by decreasing SFA content and increasing MUFA and c9t11-CLA contents in Aohan fine-wool sheep. These effects were greatest in sheep fed a diet containing 200 IU/sheep/d vitamin E.     

Growth,carcass, fiber type,and meat quality characteristics in Large White pigs with different live weights

The aim of this study was to compare the growth, carcass, histochemical, and meat quality characteristics in Large White pig groups that were categorized by live weight (Heavy and Light) and type I fiber percentage (High and Low), a procedure which resulted in four groups (Heavy-High, Heavy-Low, Light-High, and Light-Low). As expected, the Heavy group showed heavier live weight (114 vs. 94.7 kg, P<0.001) and larger loin eye area (53.3 vs. 47.8 cm², P<0.001), as well as, higher total number (1,223,000 vs. 1,140,000, P<0.05) and greater mean value cross-sectional area (CSA; 4031 vs. 3798 μm²P<0.05) of muscle fibers than the Light group. However, there were no significant differences in start and finish days among the groups (P>0.05). Heavier pigs harboring a higher percentage of type I fibers (HH) exhibited a similar mean CSA (3894 vs. 4101 μm²) and total number (1,249,000 vs. 1,198,000) of muscle fibers, even though these pigs had a greater CSA of type I fibers (3181 vs. 2719 μm², P<0.05) and a smaller CSA of type IIB fibers (4048 vs. 4457 μm², P<0.05) compared to heavier pigs harboring a lower percentage of fiber type I (HL). Both the HL and Light-Low groups exhibited a rapid decline of muscle pH at the early postmortem period (5.90 and 5.85 vs. 6.08, P<0.05), paler surfaces (43.07 and 43.55 vs. 40.73_,P<0.05), and higher degrees of fluid loss by exudation (6.26 and 6.39 vs. 4.22%, P<0.05) compared to the HH group due to their muscle fiber type composition. Thus, the HH pigs showed better meat quality characteristics without significant differences in growth and carcass performance compared to the HL pigs. Therefore, selection for increased live weight at the same age and muscle fiber characteristics, especially the increased type I fiber CSA and proportion, is one of the relevant indicators to improve and control meat quality without reducing the growth and carcass performance.     

海门山羊肌肉组织学特性的研究

[目的]研究海门山羊肌肉组织学性状对肉品质的影响。[方法]以12月龄海门山羊和波尔山羊×海门山羊F1公羊为研究对象,对海门山羊不同性别与不同部位肌肉的组织学性状进行系统的研究。[结果]海门山羊母羊股四头肌肌纤维面积及肌原纤维直径、肌节、I带、A带、H带长度极显著大于公羊（P〈0.01）,而背最长肌的肌纤维面积和肌原纤维直径、肌节、I带、A带、H带长度极显著小于公羊（P〈0.01）;同一性别不同部位肌肉之间的肌纤维显微结构与超微结构特性也存在显著（P〈0.05）与极显著差异（P〈0.01）;海门山羊公羊的肌纤维内含有大量线粒体、糖原颗粒和脂肪滴,说明其氧化代谢率高,保水性能强,柔嫩多汁,肉质优良。[结论]为海门山羊的进一步选育、开发和利用以及我国地方山羊品种评估提供了理论依据。     

海水养殖凡纳滨对虾肌肉组织蛋白质组学研究

[目的]建立分析海水养殖凡纳滨对虾肌肉组织蛋白的双向电泳图谱及技术体系。[方法]采用裂解、离心等抽提方法提取凡纳滨对虾肌肉蛋白样品,利用bradford蛋白定量试剂盒作蛋白定量后,进行一向等电聚焦电泳和二向聚丙烯酰胺凝胶电泳。电泳后的凝胶采用考马斯亮蓝染色,利用ImageScannerⅢ扫描仪扫描凝胶,获得凝胶图像。[结果]经双向电泳图谱分析显示,所获得的凡纳滨对虾肌肉蛋白点分布于pH值4．0—7．0之间,大部分蛋白为酸性蛋白,其中有部分蛋白可能存在同分异构体,高pH值区蛋白分布相对较少。[结论]首次获得海水养殖凡纳滨对虾肌肉蛋白质的双向电泳图谱,初步建立了海水养殖凡纳滨对虾肌肉组织双向电泳技术体系．可为进一步探索海水养殖凡纳滨对虾的生理生化机制及比较蛋白质组学研究提供理论依据和技术保障。     

不同加工条件下鲍鱼肌肉质构变化

[目的]探究在加工过程中温度和盐渍对鲍鱼肌肉质构的影响。[方法]在实验室条件下研究不同加工温度（809、0、100℃）和不同浓度的盐溶液（3%5、%7、%9、%）对鲍鱼肌肉质构和组织构造的影响,并与新鲜的鲍鱼相比较,从而揭示其质构的变化机理。组织构造变化采用Van Gieson染色法,质构变化采用单轴向压缩和拉伸型流变仪进行分析。[结果]加热处理和盐渍处理对鲍鱼肌肉质构和组织结构有明显影响。物性学特征参数表明,鲜活鲍鱼肌肉具有硬度大,弹性、黏聚性、咀嚼性和恢复性小的质地特点,而加热和盐渍后的鲍鱼肌肉则硬度变小,弹性、黏聚性、咀嚼性和恢复性增大。[结论]为鲍鱼深加工和方便即食食品加工提供了理论基础和试验依据。     

定安鹅IGF1基因克隆及生物信息学分析

[目的]研究定安鹅IGF1基因的结构特征及其编码蛋白的功能预测和分析。[方法]利用RT-PCR技术及生物信息分析技术,克隆并分析了定安鹅IGF1基因的cDNA序列。[结果]通过基因克隆与分析,得到558 bp的cDNA片段,其中包含1个462 bp的开放阅读框,编码153个氨基酸残基。通过Blast分析发现,鹅IGF1基因在进化上非常保守。信号肽预测分析表明,定安鹅IGF1蛋白的前49个氨基酸残基为信号肽序列。通过亚细胞定位分析发现,定安鹅IGF1成熟蛋白可能位于细胞外。[结论]该研究可为进一步研究定安鹅IGF1基因的功能奠定基础。     

舟山海域角木叶鲽营养成分分析

[目的]评估舟山海域角木叶鲽的营养水平,确定其食用价值和养殖开发前景。[方法]采用常规营养指标测定方法对角木叶鲽营养成分进行评价。[结果]角木叶鲽的脂肪含量为3.50%,蛋白质为18.70%,灰分为1.20%(FW)。共检出17种常见的氨基酸,包括7种人体必需氨基酸和4种鲜味氨基酸,必需氨基酸(EAA)占氨基酸总量的40.95%,占非必需氨基酸(NEAA)含量的69.36%,构成比例基本符合联合国粮农组织/世界卫生组织(FAO/WHO)推荐模式。维生素中维生素E含量最高,为2.35 mg/g;常量元素中K含量最高,为2 640.00 mg/kg,其次是Na和Mg;微量元素中Zn含量最高,为8.80 mg/kg,其次Fe,含量为2.00 mg/kg。[结论]角木叶鲽是营养价值较高的海水经济鱼类,具有较高的食用价值、广阔的养殖前景和市场开发潜力。     

Quantitative electromyographic examination in myogenic disorders of 6 horses

Electromyographic needle examination (EMG), including the semiautomatic quantitative analysis of motor unit action potential (MUAP), is an important diagnostic tool for myopathy in humans. The diagnostic possibilities of this technique have not been fully explored in horses; however, recent studies have shown that MUAP analysis can be performed in conscious horses. To determine the diagnostic possibilities of EMG in horses, we compared the EMG results of the subclavian muscle, the triceps, and the lateral vastus muscle in 6 equine patients thought to have myogenic disorders with those in 7 normal control horses. The EMG results were compared with the results of the histopathologic examination of the lateral vastus muscle in patients and controls. Histopathologic examination showed muscle disease in 3 patients. In the patient group, several types of abnormal spontaneous activities were observed (mainly fibrillation potentials and positive sharp waves), and the MUAPs of the patient group had a markedly shorter duration and lower amplitude than those of the control group. In the subclavian muscle, triceps, and lateral vastus muscle of affected horses, the MUAP duration was 5.0 +/- 0.4 (mean +/- SD), 3.9 +/- 0.3, and 4.7 +/- 1.1 milliseconds, respectively. The MUAP amplitude was 217 +/- 55, 150 +/- 74, and 180 +/- 54 microV; the number of phases was 2.4 +/- 0.2, 2.5 +/- 0.3, and 2.3 +/- 0.1; and the number of turns was 2.6 +/- 0.2, 2.4 +/- 0.2, and 2.8 +/- 0.5, respectively. In conclusion, it appears that the EMG may be a more sensitive method than other techniques for examining muscle biopsies for diagnosis of early-stage myopathy in horses.     

Inhibitory effect of hydrogen sulfide (H2S) on cultured rat aortic smooth muscle cells

AIM:To explore the effects of hydrogen sulfide (H₂S) on proliferation of vascular smooth muscle cells (VSMC) stimulated by endothelin (ET-1, 10^-7mol/L) and mitrogen-activated protein kinase (MAPK) activity in VSMCs.METHODS:Cultured VSMCs were divided into six groups: (1) control group, (2) serum group, (3) endothelin group, (4) NaHS groups, (5) serum+NaHS group, and (6) endothelin+NaHS group. VSMC proliferation was measured by[³H]-TdR incorporation and MAPK activity in VSMC was determined by radioactivity assay.RESULTS:ET-1 increased VSMC[³H]-TdR incorporation by 2.39 times (P＜0.01) and MAPK activity by 1.62 times(P＜0.01), as compared with control. H₂S (5×10^-5-5×10^-4mol/L) decreased VSMC[³H]-TdR incorporation and MAPK activity by 16.8%-37.4% and 7.4%-33.6%, respectively (P<0.05 or P＜0.01).CONCLUSION:This study demonstrates that H₂S inhibits ET-1-induced proliferation of VSMC, which might be mediated by the inhibition of MAPK.     

Effect of antisense oligonucleotides of c-sis on cellular cycle and proliferation of vascular smooth muscle cells in pulmonary artery

AIM:To investigate the effect of antisense oligonucleotides(ASON) of c-sis on cellular cycle and proliferation of pulmonary artery vascular smooth muscle cells(VSMC).METHODS:Tissue mass culture was done to get VSMC of pulmonary artery. Different concentrations of antisense oligonucleotides of c-sis were added into the cultures to observe the VSMC proliferation curve using MTT test. The changes of VSMC cellular cycle were also observed by flow cytometry.RESULTS:ASON with mid-to high concentrations restrained the proliferation of VSMC apparently with the peak of cell growth being attenuated or eliminated. Affected by mid-concentration ASON, PDGF-BB showed significant accelerating effect on the proliferation of VSMC. The ratio of G₀／G₁ in cellular cycle was increased significantly in VSMC culture with ASON in comparison with control. The G₀/G₁ ratio also showed significant differences among different concentration of ASON groups(P＜0.05).CONCLUSION:Mid-to high concentration of ASON was a powerful inhibitor of cellular proliferation for pulmonary artery VSMC. ASON increased the ratio of G₀／G₁ significantly and the increase seems to be ASON dosage dependent.