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171.
本试验以辽宁绒山羊和内蒙古绒山羊为实验动物,采用PCR-RFLP技术对-酪蛋白基因(CSN3)片段的Ⅰ的酶切多态性进行分析,结果表明:辽宁绒山羊和内蒙古绒山羊2个山羊群体中均存在CSN3基因Ⅰ酶切位点的多态性,且均有A、B两个等位基因。辽宁绒山羊群体等位基因A和B的基因频率分别为0.46和0.54;内蒙古绒山羊群体中等位基因A和B的基因频率分别为0.31和0.69。CSN3基因Ⅰ酶切位点的基因型分布在辽宁绒山羊群体中极显著偏离Hardy-Weinberg平衡定理(<0.01),在内蒙古绒山羊群体中符合Hardy-Weinberg平衡定理(>0.05),但两个群体间存在显著差异(<0.01)。  相似文献   
172.
The purpose of this experiment was to study the effect of gender on the slaughter performance and meat quality of Sunite sheep.Twelve 6-month-old Sunite rams and ewes at the same body condition were selected from the grazing herds of the Sunite Zuoqi Improvement Station Breeding Farm to determine their slaughter performance and meat quality.The slaughter test results showed that the bone quality and bone-meat ratio of the rams were significantly higher than that of the ewes (P<0.05),and the net meat quality and net meat rate of the ewes were significantly higher than that of the rams (P<0.05).The results of meat quality traits showed that the drip loss of ewes were significantly lower than that of rams (P<0.05),and the other indicators were not significantly different (P>0.05).The results of conventional nutrient composition of muscles showed that the intramuscular moisture content of the rams were significantly higher than that of the ewes (P<0.05),and the intramuscular fat content of the ewes were significantly higher than that of the rams (P<0.05),while the other indicators were not significantly different (P>0.05).The results of amino acid determination showed that the essential amino acid ratio in muscle of sunite ewes were significantly higher than that of rams (P<0.05),but there was no significant difference between the rams and ewes that formed the precursor amino acid content of meat flavor (P>0.05).Fatty acid measurement results showed that the saturated fatty acid ratio in the subcutaneous fat of rams was significantly lower than that of ewes (P<0.05).There was no significant difference in the ratio of saturated fatty acids in muscle fat and tail fat (P>0.05);The ratio of monounsaturated fatty acids in ewes tail fat was significantly higher than that of rams (P<0.05).The ratio of monounsaturated fatty acids in subcutaneous fat and intermuscular fat was not significantly different between rams and ewes (P>0.05).The ratio of polyunsaturated fatty acids in intermuscular fat of rams was significantly higher than that of ewes (P<0.05),and there was no significant difference in the content of polyunsaturated fatty acids in subcutaneous fat and tail fat (P>0.05).In summary,it showed that gender had a certain influence on the slaughter performance and meat quality of 6-month-old Sunite sheep.  相似文献   
173.
利用临床观察、病理解剖、PCR、RT-PCR、ELISA、中和抗体检测等方法,对口蹄疫(FMD)重组鸡痘病毒(FPV)在豚鼠、仔猪体内的毒性、分布以及抗体消长规律进行研究。结果表明,FMD重组鸡痘病毒免疫的动物在整个试验期间,未表现出明显的临床症状和不良反应;病理组织切片检测无明显的组织学变化;PCR、RT-PCR检测证明,豚鼠、猪免疫FMD重组鸡痘病毒后,在心脏、肝脏、脾脏、肺脏、肾脏、肌肉、脑、肠系膜淋巴结内检测到FPVDNA和FMDV DNA,且在大部分组织能存在3 d左右;FMD重组鸡痘病毒均可诱导免疫动物产生较高水平的抗FMDV特异性抗体和中和抗体,验证了所构建重组FPV的生物安全性及良好的免疫原性,为其他哺乳动物实验提供了必要的基础数据。  相似文献   
174.
选用平均体重为(40±2)kg杜长大三元杂交去势公猪3头,按3×3的拉丁方进行试验设计,试验分3期,每期为7 d,采用全收粪法,研究不同蛋白质(CP)水平的氨基酸平衡日粮CP水平分别为14%、16%和18%)对氮、磷及能量代谢的影响。结果表明:不同蛋白质水平日粮处理间的氮表观消化率差异不显(著P>0.05),氮的沉积率以14%CP和16%CP组显著高于18%CP组(P<0.05),而14%CP和16%CP组之间无显著差异(P>0.05)。粪氮排出量14%CP日粮组显著低于16%CP和18%CP日粮组(P<0.05),16%CP日粮组和18%CP日粮组间无显著差异(P>0.05)。随着日粮蛋白质水平下降,生长猪的氮排出量、粪氮和尿氮均减少,总排泄氮中尿氮的比例较大,而粪氮则较少。不同蛋白质水平日粮对磷和能量的消化利用无显著影响(P>0.05)。  相似文献   
175.
0.1%氯吡脲可溶性液剂对西瓜产量和品质的影响   总被引:2,自引:0,他引:2  
0.1%氯吡脲可溶性液剂50 mg/kg、45 mg/kg、40 mg/kg(毫克/公斤)(有效含量)涂抹西瓜雌花果柄可显著提高西瓜座果率,从而提高西瓜产量,同时在一定程度上可增加西瓜的含糖量和维生素C的含量.  相似文献   
176.
AIM:To observe the influence of APP17-mer peptide on the learning and memory,and oxidative stress in mitochondria in hipp ocampal neurons of senescence accelerated mouse/prone 10 (SAMP10).METHODS:The 4-month-old SAMP 10s were randomly divided into mod el group and APP17-mer peptide group (the model group+APP17-mer peptide).The se nescence accelerated mouse/resistance1 (SAMR1) were used for normal control.The APP17-mer peptide group was injected with APP17-mer peptide subcutaneously in a dose of 0.34 μg/per mouse,three times a week;while the model group and the control group were injected with saline.After 28 weeks,water maze test was use d to evaluate the learning and memory of these mice.Then hydroxy lamine reactio n and thiobarbituric acid reaction were used to assay the activity of superoxid e dismutase (SOD) and contents of malondialdehyde (MDA) in mitochondria in hippo campal neurons,respectively.RESULTS:(1) The water maze test showed that the full-course swi mming time and numbers of error committed in model group were significantly incr eased as compared with the normal control (P<0.05).The results in APP17-me r peptide treated group were the same as that in normal control group.(2) Compa red with the normal control,the activity of SOD decreased in model group (P <0.01),and the contents of MDA increased (P<0.01).APP17-mer partially re versed the increase in MDA and the decrease in SOD.The content of MDA was lower and the activity of SOD was higher in APP17-mer peptide group than those in mod el group (P<0.05).CONCLUSION:The learning and memory deficit in SAMP10 are observ ed,and the balance of free radical generation/free radical scavenger is impai red.APP17-mer peptide has an antioxidant character and corrects the abnormal ch ange of SOD and MDA,which may be related to its protective effect of learning and memory.  相似文献   
177.
AIM: To study the effects of body position on the physiological and pathological changes in an oleic acid-induced acute lung injury (ALI) model. METHODS: One control group and three experimental groups were set up in which the rabbits were put on supine, prone and rotation, respectively. The changes of blood pressure, heart rate and partial pressure of arterial oxygen, lung mechanics, cytokines in the course of experiment and pathologic changes were observed. RESULTS: At the end of experiment, heart rate in rotated rabbits was lower than that in prone rabbits [(176.13±26.55) beats/min vs (217.75±14.44) beats/min, P<0.05]. Partial pressure of arterial oxygen and lung compliance in prone and rotated rabbits were higher than that in supine rabbits [(157.75±51.19) mmHg and (166.08±37.07) mmHg vs (86.59±23.82) mmHg, (2.75±0.89) mL/cmH2O and (2.63±0.74) mL/cmH2O vs (1.63±0.52) mL/cmH2O, respectively, P<0.05], but intrapulmonary shunt was just up side down. Airway peak inspiration pressure in rotated rabbits was higher than that in prone group rabbits, [(19.63±2.45) cmH2O vs (16.00±2.27) cmH2O, P<0.05]. TNF-α in supine and rotated rabbits was higher than that in control rabbits, [(3.12±0.83 and 2.59±0.79) μg/L vs (1.36±0.34) μg/L], but it was not the case in prone rabbits. Partial pressure of arterial oxygen was positive correlation to lung compliance and negative correlation to intrapulmonary shunt. Dorsal lung edema was more severe than ventral in group 2, ventral lung edema was more severe than dorsal in group 3 and lung edema was diffused in group 4. CONCLUSIONS: Prone and rotation positions increased lung compliance and decreased intrapulmonary shunt accompanied with oxygenation improvement in ALI model, but prone was safer than rotation position, the former can inhibit the secretion of TNF-α. The distribution of lung edema changed with body position changes.  相似文献   
178.
山东省农药械使用现状、存在问题及"十一五"应对措施   总被引:1,自引:0,他引:1  
“十五”期间,各地都十分重视农产品农药残留问题,大力发展无公害农产品,建立无公害农产品生产基地,建设示范园区,引导农民安全使用农药。山东省自20世纪90年代起开展了“二减一保”工程。当前省政府又投资开展“绿卡”行动计划,通过项目的实施以及各级植保部门的大量试验,筛选出适合不同作物防治病、虫、杂草的安全有效的农药品种,并已初见成效。但是,其中的施药环节,包括施药技术和施药器械,由于长期以来未受到应有的重视,广大农民了解不够深入,虽然引进推广了大量的新型器械和施药技术,但由于受到当前许多客观因素的制约,施药技术的提高…  相似文献   
179.
无子沙糖橘(十月橘)的选育   总被引:8,自引:1,他引:8  
采用芽变选种的方法,在四会市石狗镇选出了无子柑橘新品种—无子沙糖橘(十月橘)。果略小,单果重平均40g左右,单果平均种子数0.5粒以内,达到柑橘无子的标准。果实扁平,皮橘红色,薄而脆;果肉橙黄色,味清甜,可溶性固形物13%以上,肉质爽脆化渣,品质上等。早结丰产性好,发梢能力强,3月上中旬开花,12月上旬果实开始成熟。  相似文献   
180.
荔枝果皮褐变程度的数学模型研究(英文)   总被引:2,自引:0,他引:2  
为了明确荔枝采后果皮褐变的程度,为生产上的分级和研究中定量果皮的褐变程度提供依据,以淮枝、糯米糍、桂味为材料,研究了采后其果皮颜色变化过程中亮度(L*)、色饱和度(C*)、色度角(h)值及a*值和b*值的变化规律,探讨这些指标与褐变程度的关系,并推导出褐变与这些指标变化相关的方程式。结果表明,色度指标L*,a*,b*和C*值的变化均可用于衡量荔枝果皮的褐变程度,其中以C*值的相关性最高,并确定了3个品种荔枝C*值与褐变程度的对应关系,将荔枝果皮褐变程度数量化,建立荔枝果皮褐变程度的数学模型。  相似文献   
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