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991.
Poults 3 weeks and older developed temporary tracheal resistance to intranasal challenge following inoculation of either Artvax vaccine or formalin-inactivated Bordetella avium bacterin by the intranasal and eyedrop routes. Resistance usually persisted for 3-4 weeks after B. avium challenge. However, with constant exposure to infected controls, the vaccinated birds eventually developed tracheal infection. Day-old poults did not respond to either the Artvax or the bacterin and were completely susceptible to challenge. Two-week-old poults responded to some degree, but poults 3 weeks old and older responded best. Poults inoculated with bacterin by aerosol or by drinking water did not respond as well as those inoculated by the intranasal and eyedrop routes. When poults were given a single subcutaneous injection at 3 weeks of age and challenged 2 weeks later, three of five resisted infection for 18 days.  相似文献   
992.
Book review     
Livestock Environment II, Proceedings of the Second International Livestock Environment Symposium, American Society of Agricultural Engineers, Publication 3–82. American Technical Publishers Ltd, Hitchin, England. Price £27.00. ISBN 0–916150–45–3.  相似文献   
993.
Lactic acid as a decontaminant in slaughter and processing procedures   总被引:1,自引:0,他引:1  
An attempt was made to interrelate the data obtained in experiments conducted by our Department along beef, veal and pig slaughter lines, using lactic acid (LA) for the decontamination of carcasses, cold and hot boned primal cuts, slaughter byproducts, and butcher's knives. First and foremost it was observed, that provided Good Manufacturing Practices are strictly followed, the microbial load of carcass surfaces will be substantially reduced. LA-decontamination may result in an additional reduction. Since in the early post-mortem period bacteria are not yet attached to the meat surface, LA-decontamination should preferably be applied to the hot carcass. It was demonstrated that, dependent on mode and duration of application, LA sprays not exceeding 1% v/v (beef), 1.25% v/v (veal) and 1.5% v/v (pork) resulted in acceptable carcass colour scores. Blood spots, which are particularly prone to discolouration by lactic acid application, should be removed at an early post-mortem stage e.g. by strong showering. The difference in surface pH between LA-treated and control carcasses disappeared within 72 hours post-mortem. Veal longissimus chops treated with LA solutions up to 2% v/v were not identified by a consumer taste panel as significantly different from controls. The 'immediate' bactericidal effect of LA-decontamination for beef, veal and pig carcasses, as well as for pig liver and veal brain, amounted to approximately 1.5 log cycles for the aerobic colony counts, strongly dependent on substrate and conditions of decontamination. In addition, a 'delayed' bacteriostatic effect was observed during storage, which is probably the result of a prolonged lag phase of acid-injured micro-organisms surviving lactic acid decontamination.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
Surgical treatment of hepatic and biliary disease requires a thorough knowledge of pertinent anatomy and pathophysiology. Proper attention to both preoperative and postoperative care is important. This article describes many of the more common surgical manipulations of the liver and biliary tract, as well as pre- and postoperative considerations.  相似文献   
995.
The authors discuss the liver's influence on drug disposition in the body and the influence of drugs on the liver. Drug-induced hepatotoxicity with regard to mechanisms and causative agents is discussed, as well as administration of drugs to patients with existing liver disease.  相似文献   
996.
Epidemiological studies on bovine ocular carcinoma were reviewed. Reports on the frequency and the distribution of the disease indicate that it is still a very prevalent and economically important disease. It is recognized throughout North America, but is more frequent in lower latitudes under range conditions. Etiological factors including ultraviolet light, circumocular apigmentation and viruses, as well as the pathogenesis, are considered in light of current knowledge on carcinogenesis of this tumor. It is likely that the induction of bovine ocular carcinoma is multifactorial and the precise roles played by each of the various factors are not yet understood.  相似文献   
997.
A technique for rapidly separating platelets from small quantities of whole blood is described. The isolation method allowed for counting and sizing platelets by electronic means, and counts with this new method were closely correlated with those obtained by phase microscopy. Platelet sizing was possible because of the inert and isotonic nature of the density-gradient medium used in the procedure. The technique was applicable to samples of blood from persons, horses, cattle, sheep, goats, pigs, dogs, mice, rats, guinea pigs, and rabbits. The isolation of platelets from whole blood of various species of animals was necessary for electronic counting because of the great variation in sizes of platelets and erythrocytes and the variable sedimentation properties of animal blood.  相似文献   
998.
Congenital lobar emphysema is described in two dogs. The condition was characterized by progressive dyspnoea and cyanosis from a very young age. There was marked expiratory effort, and wheezing and crackling were evident on auscultation. Radiographic examination revealed overdistension and emphysema of the right middle lobe with displacement of the heart and mediastinum to the opposite side. The pathology and possible treatments are discussed.  相似文献   
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