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991.
Ruminai acidosis was induced in twenty-one 10-month-old West African Dwarf Goats by feeding a suspension of 80 g wheat flour per kg body-weight (day 0) through a stomach tube. Ruminai and systemic acidosis was diagnosed on day 1 in all goats. Clinical signs included loss of rumination and appetite, trembling, and watery diarrhoea. The detection of acidic faeces during the first 24h was considered of diagnostic importance. Subgroups were treated orally on days 1,2, and 3 either with 1 g of sodium bicarbonate per kg bodyweight, with 1 g of baking yeast per kg, or with a combination of these treatments at 0.5 g of each per kg. A fourth group served as untreated controls.Peroral bicarbonate neutralization was highly effective in the treatment of rumen acidosis, whereas the use of yeast was found ineffective. The combined treatment had a moderate effect probably due to the bicarbonate.Three fatal cases (60%) occurred in the untreated group compared with none in the bicarbonate group, and 2 in each of the remaining groups. This corresponded to 33% of the yeast treated group and 40% of the combined treated group. Details were given on post mortem examinations performed on all survivors on day 11. Lesions included subacute rumenitis and abomasal ulcers. No lesions were found in 3 of the bicarbonate treated goats and in 2 of the animals receiving combined treatment.  相似文献   
992.
Two separate groups of nine-week-old specific pathogen free cockerels maintained in isolation were infected with a field strain of infectious laryngotracheitis (ILT) virus, either by intratracheal or combined intranasal and supraconjunctival inoculation. Birds were monitored for virus shedding from five sites on alternate days during the acute phase and three times weekly until week 17. They were then treated with cyclophosphamide on three consecutive days and thereafter swabbed daily. During the acute phase clinical signs were observed and virus was recovered from ocular and nasal sites for up to six to eight days. Initially after the acute phase no virus could be detected. However, from the seventh week after infection intermittent, apparently spontaneous shedding was detected in four of five birds in each group. There was no clear effect of cyclophosphamide treatment on re-excretion patterns, possibly because of the high levels of virus shedding already occurring. Thus, a carrier state for ILT virus has been demonstrated experimentally in live clinically recovered birds.  相似文献   
993.
Pharmacokinetics of oxytetracycline hydrochloride in rabbits   总被引:1,自引:0,他引:1  
Pharmacokinetics of oxytetracycline HCl (OTC) was studied in rabbits. After 10 mg of OTC/kg of body weight was administered IV, the distribution half-life was 0.06 hour, terminal half-life was 1.32 hours, volume of distribution area was 0.861 L/kg, and total body clearance was 0.434 L/kg/h. After 10 mg of OTC/kg was given IM, the absorption half-life was 2.09 hours, extent of absorption was 71.4%, and total body clearance of the absorbed fraction was 0.576 L/kg/h. Based on these kinetic data, a dosage of 15 mg of OTC/kg, every 8 hours was developed. This dose given IM for 7 consecutive days resulted in observed steady-state maximum and minimum concentrations (mean +/- SD) of 4.7 +/- 0.3 micrograms/ml and 3.2 +/- 0.6 micrograms/ml, respectively. Twice this dose (30 mg of OTC/kg, every 8 hours) given IM caused anorexia and diarrhea.  相似文献   
994.
The occurrence and incidence of pneumonia in housed calves were not related to the selenium status of the herd as measured by blood glutathione peroxidase activity nor were they affected by selenium treatment of calves during the neonatal period. Pneumonia was related more closely to herd size and building design.  相似文献   
995.
The pathology of lens-induced uveitis in dogs   总被引:3,自引:0,他引:3  
Rupture of the lens capsule in 20 dogs resulted in zonal, perilenticular inflammation that did not respond to symptomatic therapy and resulted in the loss of the globe. The reaction was dominated by lens epithelial proliferation, pupillary occlusion, and glaucoma in 11 of the 20. This reaction, herein named phacoclastic uveitis, is unique and easily distinguished from the mild lymphocytic-plasmacytic anterior uveitis that accompanies leakage of lens material through an intact capsule of a hypermature cataract (phacolytic uveitis). None of the dog eyes had the granulomatous perilenticular inflammation that is the hallmark of lens-induced (phacoanaphylactic) uveitis in humans.  相似文献   
996.
997.
Salmonella typhimurium was isolated from nine of 60 wild sparrows trapped in the Guelph area. While this organism was isolated from birds trapped at several different locations, the highest prevalence was in sparrows trapped in close proximity to an animal clinic. The significance of these findings in relation to human and animal salmonellosis is discussed.  相似文献   
998.
999.
The inflammatory host response to Schistosoma bovis in young goats was studied at necropsy by light microscopy 34 weeks after primary exposure to 3,000 cercariae (group B, n=6), 34 weeks after primary exposure to 3,000 cercariae followed by challenge with 2,500 cercariae at week 17 (group C, n=5), and 17 weeks after primary exposure to 2,500 cercariae, given on week 17 of the experiment (group D, n=6). Three goats served as uninfected controls. The faecal egg output had been minimal for 17 weeks prior to necropsy in groups B and C and only for the last 2 weeks in group D.Histological studies were carried out on the small intestine, liver, lung and spleen, and tissue egg counts were performed. In sections of the small intestine and liver, a panel of histopathological variables were quantitated to characterize the host response and differences between groups of animals were evaluated with one way analysis of variance. The mean tissue egg count in the small intestine was slightly but not significantly higher in group C than group B and about twice as high in group D (D vs B or C p<0.01). Group means of numbers of inflammatory foci per section of gut wall corresponded well with those of tissue egg counts, suggesting that the rate of inflammatory destruction of eggs did not differ markedly between the groups. Egg material was less commonly seen in granulomas of the small intestine in group B than in group D (p<0.01), suggesting lower passage of eggs through the gut wall during the later than during the earlier phase of patent primary infection. The frequency of eosinophil-rich hepatic inflammatory foci was much higher in group D than in the other groups (D vs B p<0.05, D vs C p< 0.01), and coincided with a high degree of blood eosinophilia in this group at the time of sacrifice. Challenged goats showed a significantly higher frequency of markedly fibrotic inflammatory foci in the liver and of liver granulomas with a marked giant cell component than goats of the other groups. Hepatic portal fibrosis was least prominent in animals with 17- week- old primary infections, implying a possible relation between this change and duration of infection.  相似文献   
1000.
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