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91.
母猪饲料中添加中药“泻康宁”对仔猪黄白痢的治疗试验 总被引:3,自引:0,他引:3
由埃希氏大肠杆菌引起的仔猪黄白痢会导致机体水分和电解质大量丧失 ,使机体衰弱甚至死亡 ,从而造成很大的经济损失。目前 ,大肠杆菌引起的仔猪黄白痢已成为影响仔猪发育和育成的重要疾病之一 ,成为养猪业的一大障碍。虽然应用抗生素、磺胺类药物和抗菌增效剂等治疗仔猪黄白痢有一定的疗效 ,但由于大肠杆菌具有很强的变异性 ,易产生抗药性而影响治疗效果 ,而且 ,有的药物还会在体内蓄积 ,给人类的健康带来危害 ,正因为如此 ,人们开始寻找新的无公害的药物。实验研究发现 ,中草药不仅能够促进畜禽生长发育和提高生产性能 ,调节动物机体的新陈… 相似文献
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D E Brooks D A Samuelson K N Gelatt P J Smith 《American journal of veterinary research》1989,50(6):908-914
Scanning electron microscopy of vascular corrosion casts of the optic nerve region in normal and glaucomatous Beagles demonstrated that the blood supply to the laminar optic nerve is derived from short posterior ciliary arteries, cilioretinal arteries, and longitudinal pial vessels. The short posterior ciliary arteries formed a ring of striated pillars around the scleral canal. The central retinal artery was not present in the dog. Differences between the casts in normal and glaucomatous dogs were not detected. 相似文献
95.
四川的云南松地径胸径相关关系及其应用研究 总被引:9,自引:1,他引:8
本文报道了四川的云南松树干在部三个不同部位直径(地表直径d0.00、0.05m高处直径d0.05、0.1Om高处直径d0.10)与胸径(d1.3)的相关关系,利用其编制了四川云南松地径一元材积表,并对其在四川云南松林区进行盗伐木、滥砍乱伐木材积估计和监测森林资源消耗量等方面的应用进行了探讨。四川云南松地径与胸径最佳关系模型为二次抛物线回归方程,相关系数r=0,999217~0.999380,剩余平方和Q=179.3391~226.4480,且d0.10与d1.3相关关系最为紧密。 相似文献
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Outbreaks of infection due to a parapoxvirus were reported on eight New Zealand deer farms. Scabby lesions were seen variably on the muzzle, lips, face, ears and neck of red deer (Cervus elaphus) with morbidity rates reaching 100%. On three farms multifocal lesions were also present on the velvet. Deaths were reported on two properties where the lesions were extensive and secondary bacterial infections had occurred. On one of these farms multifactorial disease was suspected. Poxvirus particles were seen by negative contrast electron microscopy in scab material from all eight properties. Morphologically the deer virus resembled a parapoxvirus, but restriction endonuclease analysis showed its DNA fragment patterns were distinct from those of orf (contagious ecthyma) virus. 相似文献
98.
Fatty acid profiles and sensory and carcass traits of tissues from steers and swine fed an elevated monounsaturated fat diet 总被引:4,自引:0,他引:4
L C St John C R Young D A Knabe L D Thompson G T Schelling S M Grundy S B Smith 《Journal of animal science》1987,64(5):1441-1447
Twelve Angus X Hereford steers were assigned to either a control high-energy diet or a test diet consisting of 20% rapeseed at the expense of 20% corn. Twelve pigs were allotted to a control diet and two test diets containing either 10 or 20% canola oil (CO). Both CO and oil in the rapeseed contained 60 to 64% oleic acid. Cattle fed rapeseed exhibited little effect from the diet due to apparent indigestibility of the rapeseed. Total saturated fatty acids decreased from 40% in adipose tissue of the control pigs to 15% in the 20% CO-fed pigs. The ratio of monounsaturated to saturated fatty acids (M/S) increased from 1.19 in adipose tissue from control pigs to 3.63 with the addition of 20% CO to the diet. In muscle, the M/S ratio increased from 1.21 in control pigs to 2.46 in the 20% CO treatment group. The percentage of the saturated fatty acids in muscle decreased from 42% in the control to 23% in the 20% CO treatment. Significant increases in "oiliness" and decreases in fat firmness were observed when increasing levels of canola oil were fed. Sensory traits, cooking loss and shear-force values of pork chops were similar among treatment groups. In conclusion, monounsaturated fatty acid content can be elevated substantially in pork without adversely influencing the quality of the meat, thus producing a product perceived to be more healthful by the consumer. 相似文献
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