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991.
本研究采用PCR RFLP法对莱芜黑猪FUTⅠ基因M307位点多态性及其与生长性能的关系进行分析。结果表明:莱芜黑猪FUTⅠ基因M307位点均存在丰富的多态性,而且在该突变位点显著偏离Hardy Weinberg平衡状态(P<0.01)。3种基因型对莱芜黑猪的初生重、断奶重和70日龄保育重(和断奶仔猪腹泻和水肿病密切相关)等均无显著影响(P>0.05)。本研究结果提示:肠毒素大肠杆菌 F18抗性基因有可能起源于西方猪种,对莱芜黑猪无显著影响,有必要对其中所具备的遗传抗性做更深入的研究,寻找、定位其相应的QTL和抗性基因。 相似文献
992.
Tropical Animal Health and Production - 相似文献
993.
根据遗传、性别、体重等相一致的原则,将80头35日龄断奶仔猪随机分成4个组,每组20头。对照组不合大蒜和大蒜素,试验1组添加3%的大蒜,试验2组在对照组基础上添加100mg/kg大蒜素,试验3组为200mg/kg大蒜素组,饲养31d,探讨对仔猪生产性能和血液生化指标的影响。结果表明:大蒜组仔猪日增重较对照组提高了18%,料重比降低14%,饲粮中添加100mg/kg和200mg/kg大蒜素可使仔猪日增重较对照组分别提高5.5%(P〉0.05)和17.9%(P〈0.05),料重比分别下降4.39/6和8.2%。3个试验组断奶仔猪腹泻率均比对照组低。对血液生化指标的测定表明:大蒜和大蒜素显著降低了仔猪血清尿素氮(P〈0.05),总蛋白和球蛋白比对照组有提高,但对血糖、白蛋白、血钙、血磷等影响不大。说明大蒜和大蒜素促进仔猪生产性能的提高,并具有提高免疫力、改善氮沉积,减少腹泻的效果。 相似文献
994.
猪血清淀粉酶多态性及遗传规律研究 总被引:2,自引:0,他引:2
采集267头二花脸、大约克纯种猪及它们的不同杂交组合后代血样,利用水平聚丙烯酰胺凝胶电泳法,对血清中淀粉酶(Am)的遗传多态型及遗传规律进行研究,并分析了血清淀粉酶型对猪初生重的影响。结果表明猪血清症粉酶表现出多态性,有九种表现型并分别受四个共显性复等位基因控制,而其他文献大多提及Am受三个共显性复等位基因控制,并有六种表现型。Am基因型的九个交配组合后代基因型经X ̄2检验,有两个交配组合(BD×CD,BD×AD)的分离比X ̄2值P<0.01差异极显著;有两个组合(BD×BC,BC×CD)的分离比X ̄2值P<0.05,差异显著;其他五个组合(BD×AC,CD×BB,CD×AB,BD×CC,BC×DD),分离比X ̄2值P>0.05,差异不显著,符合孟德尔遗传规律。有些交配组合分离比与预期比不符合,是否由于某些基因型与生命力有关,还有待于进一步探讨。猪血清淀粉酶型与仔猪初生重相关关系不明显。 相似文献
995.
本试验旨在研究不同品种猪在不同生理阶段骨骼肌葡萄糖转运载体(GLUT)1、GLUT4和胰岛素受体(IR)mRNA表达的发育规律.试验以1、7、30、60、90和150日龄蓝塘和长白两品种猪背最长肌、半膜肌和半腱肌组织样品cDNA为模板,采用实时荧光半定量PCR的方法,检测猪GLUT1和GLUT4 mRNA在不同骨骼肌中的表达模式.结果显示:1)1~ 150日龄蓝塘和长白猪背最长肌、半膜肌和半腱肌GLUT1 mRNA表达存在相似的发育变化规律,在1日龄时相对表达丰度最高.2)1 ~ 150日龄蓝塘和长白猪半膜肌和半腱肌GLUT4 mRNA相对表达丰度随日龄呈波形式变化,变化速度和程度存在品种差异.1日龄和150日龄时蓝塘猪背最长肌GLUT4mRNA相对表达丰度低于同日龄长白猪(P>0.05),而在其余日龄时高于同日龄长白猪(P>0.05).3)蓝塘和长白猪背最长肌、半膜肌和半腱肌IR mRNA相对表达丰度在1和30日龄时表现出较高水平,而在7、60、90和150日龄时无显著差异(P>0.05);同日龄蓝塘和长白猪之间IR mRNA相对表达丰度无显著性差异(P>0.05).结果表明:猪骨骼肌GLUT1 mRNA的表达在不同生理阶段存在差异,猪骨骼肌GLUT4 mRNA的表达在不同品种和生理阶段存在显著差异,且其与IR mRNA的表达相关性较弱,无明显规律. 相似文献
996.
在当前集约化生产的猪场中,约有10%的仔猪由于各种原因导致生长受阻形成“僵猪”。僵猪生长发育迟缓,饲料转换率低,免疫力差、易染病而成为猪群的传染源。对僵猪的处理方式不当会造成饲料的浪费与猪只的损失,期间给猪场或养殖户造成较大的经济损失。文章浅析了生长受阻仔猪形成的原因,提出了一些相对应的防治策略,以期为从事养猪的工作者提供参考。 相似文献
997.
Epidemiological studies of pig diseases: 2. Post-weaning diarrhoea and performance in Western Australian pigs 总被引:1,自引:0,他引:1
SZ SKIRROW JR BUDDLE AR MERCY F. MADEC RR NICHOLLS 《Australian veterinary journal》1997,75(4):282-288
Objective To determine in Australian pig herds the accuracy of French protocols for risk factor assessment of post-weaning diarrhoea and illthrift.
Procedure French protocols for the collection of data on health indicators and risk factors for post-weaning diarrhoea were conducted on 54 batches of weaner pigs from 28 Western Australian pig herds during three years.
Results Large variations in post-weaning performance were found. About one-third of the batches were growing at <200 g/day during the 3 weeks after weaning, and 54% had growth rates of <250 g/day. Weaning age and weight of at least 30 days and 7.9 kg, respectively, optimised weaner performance. Other risk factors associated with little post-weaning diarrhoea and good weaner performance were high creep feed intakes, relatively little diarrhoea as suckers, and, contrary to expectations, large temperature fluctuations.
Conclusion Overall, the 'predictability' of post-weaning problems as assessed by measurement of risk status, was good. However, the model was less accurate at predicting the performance of a single batch of pigs. 相似文献
Procedure French protocols for the collection of data on health indicators and risk factors for post-weaning diarrhoea were conducted on 54 batches of weaner pigs from 28 Western Australian pig herds during three years.
Results Large variations in post-weaning performance were found. About one-third of the batches were growing at <200 g/day during the 3 weeks after weaning, and 54% had growth rates of <250 g/day. Weaning age and weight of at least 30 days and 7.9 kg, respectively, optimised weaner performance. Other risk factors associated with little post-weaning diarrhoea and good weaner performance were high creep feed intakes, relatively little diarrhoea as suckers, and, contrary to expectations, large temperature fluctuations.
Conclusion Overall, the 'predictability' of post-weaning problems as assessed by measurement of risk status, was good. However, the model was less accurate at predicting the performance of a single batch of pigs. 相似文献
998.
对杜洛克×皖北猪杂种适宰体重的试验结果表明,肥育猪的增重速度随体重增长而提高,70千克时日增重696.7克,90千克时提高到810.7克,增长幅度达10.8%,体重90千克以后增重速度虽仍有一定上升,但增长的幅度平均仅0.5%;饲料效率随体重增大逐渐降低,70千克时与90千克相比,每增重1千克少耗料0.62千克,90千克与110千克相比,又少耗0.84千克;胴体瘦肉率随体重增长逐渐降低,体重每增加10千克,瘦肉率降低1.24%,其间的相关系数为-0.7499;脂肪率则相反,相关系数为0.6337。随体重升降的转折点在90千克。90千克时的利润函数最高,综合经济效益最好。故90千克屠宰是适宜的,最好不超过100千克。 相似文献
999.
Dario dOvidio Francesco Marino Emilio Noviello Enrico Lanaro Paolo Monticelli Chiara Adami 《Veterinary anaesthesia and analgesia》2018,45(2):183-189
Objective
To evaluate the efficacy and side effects of alfaxalone administered intramuscularly (IM) as a sedative agent in guinea pigs undergoing survey radiographs.Study design
Prospective clinical trial.Animals
A total of 30 client-owned guinea pigs.Methods
Following baseline assessments, 5 mg kg?1 alfaxalone was administered IM. Heart rate, arterial haemoglobin oxygen saturation, respiratory rate, rectal body temperature, palpebral reflex, response to toe and ear pinch, righting reflex, posture, jaw tone and reaction to manipulation were assessed before and after sedation at 5-minute intervals. The time elapsed from onset of sedation to return of locomotion and coordinated limb movements, the quality of recovery and the occurrence of undesired effects were observed and recorded.Results
The mean ± standard deviation onset of sedation was 2.7 ± 0.6 minutes. The physiological variables remained within normal ranges until completion of the procedure. Palpebral reflex and responsiveness to both ear and toe pinch were maintained during sedation. Neither hypoxaemia nor hypothermia was observed. The duration of sedation was 29.3 ± 3.2 minutes. Sedation and recovery were uneventful, and adverse effects were not observed.Conclusions and clinical relevance
In conclusion, 5 mg kg?1 of IM alfaxalone represents a valuable sedation protocol for healthy guinea pigs undergoing minor noninvasive procedures. Further trials are required to investigate its cardiovascular effects, clinical usefulness in unhealthy patients and its combined use with analgesics for procedures associated with nociception. 相似文献1000.