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61.
The case records of 37 cats treated for nasopharyngeal or aural inflammatory polyps were reviewed. Thirty of them were managed conservatively with the polyp being removed by traction alone. Long-term follow-up information was available for 22 cats, of which 13 (59 per cent) had no recurrence of clinical signs. The remaining nine cats required recurrent polyps to be removed surgically. Cats with only nasopharyngeal polyps were nearly four times more likely to be cured by traction alone than cats with aural polyps, and none of the cats that was treated with prednisolone after traction suffered a recurrence. Cats with more severe aural signs were more likely to require surgery.  相似文献   
62.
The pharmacokinetics of a long‐acting oxytetracycline (OTC) formulation (Liquamycin® LA‐200®) injected intramuscularly (i.m.) at a dose of 20 mg/kg were determined in four calves and 24 sheep to determine if the approved label dose for cattle provided a similar serum time/concentration profile in sheep. The AUC for the calves was 168±14.6 (μg ? h/mL) and was significantly less than the AUC for sheep (209±43 μg ? h/mL). Using the standard two‐stage approach and a one‐compartment model, the mean Cmax for the calves was 5.2±0.8 μg/mL, and for the sheep was 6.1±1.3 μg/mL. The mean terminal phase rate constants were 0.031 and 0.033 h, and the Vdss were 3.3 and 3.08 L/kg for the calves and sheep respectively. Analysis of the data using the standard two‐stage approach, the naive pooled‐data approach and a population model gave very similar results for both the cattle and sheep data. Sheep tissue residues of OTC in serum, liver, kidney, fat, muscle and injection site were measured at 1, 2, 3, 5, 7 and 14 days after a single i.m. injection of 20 mg/kg OTC. Half‐lives of OTC residues in the tissues were 38.6, 33.4, 28.6, 25.4, 21.3, and 19.9 h for injection site, kidney, muscle, liver, mesenteric fat and renal fat, respectively. The ratio of tissue to serum concentration was fairly consistent at all slaughter times, except for the fat and injection sites. The mean ratios were 1.72, 4.19, 0.11, 0.061, 0.84 and 827 for the liver, kidney, renal fat, mesenteric fat, muscle and injection sites, respectively. The tissue concentrations of OTC residues were below the established cattle tolerances for OTC in liver (6 p.p.m.), muscle (2 p.p.m.) and kidney (12 p.p.m.) by 48 h, and in injection site muscle by 14 days after the single i.m. injection of 20 mg/kg.  相似文献   
63.
A 6-year-old Simmental cow infected with Theileria buffeli had a clinical disease characterized by theilerial parasitemia, macrocytic normochromic anemia with acanthocytosis and spherocytosis, lymphoid hyperplasia (lymphocytosis, edematous lymphadenomegaly), dysproteinemia, evidence of liver disease, and a low serum antibody titer against T. buffeli. The cow was in a herd in which all cattle originated in Missouri; 22/75 (29%) of cattle had a theilerial parasitemia and 26/75 (35%) had titers to T. buffeli of > or =1:160. Classification of the Missouri bovine organism as T. buffeli was based on DNA sequencing and comparison to sequences for T. buffeli and Theileria sp. type A obtained from GenBank. Intraerythrocytic veils and piroplasms were seen during transmission electron microscopy. The organism was successfully transmitted to two splenectomized calves, which developed mild anemias while parasitemic. Blood from the second calf was used as the source of T. buffeli antigen for an indirect immunofluorescence antibody test. Theilerial isolates from a Missouri white-tailed deer were also sequenced and resembled Theileria sp. types F and G and were not consistent with the bovine organism.  相似文献   
64.
Objective To measure plasma cortisol responses in calves dehorned using a scoop after administration of local anaesthesia and/or cautery of the wounds.
Design A physiological study with controls.
Procedure There were six treatments: control handling with and without local anaesthesia, dehorning, dehorning after local anaesthesia, dehorning followed by wound cautery, and dehorning after local anaesthesia followed by wound cautery. Blood samples were taken before and after dehorning.
Results Dehorning caused an increase in plasma cortisol concentrations, which decreased a little to plateau values and then declined to pretreatment values 3 to 4 h after dehorning. The peak was smaller after local anaesthesia was administered but when its effects wore off, cortisol concentrations increased and thereafter were similar to those in the dehorned animals. The combination of local anaesthesia and cautery resulted in a plasma cortisol response similar to those in control calves with or without local anaesthesia.
Conclusions If plasma cortisol concentrations reflect the distress being experienced by the calves, then local anaesthesia reduces the acute distress for about 3 h after dehorning but not during the subsequent 3 to 4 h. Combining local anaesthetic and cautery prevented the significant increase in plasma cortisol following dehorning and may eliminate the acute distress caused by scoop dehorning.  相似文献   
65.
We estimated the population density of dogs by distance sampling and assessed the potential utility of two marking methods for capture-mark-recapture applications following a mass canine rabies-vaccination campaign in Sorsogon Province, the Republic of the Philippines. Thirty villages selected to assess vaccine coverage and for dog surveys were visited 1 to 11 days after the vaccinating team. Measurements of the distance of dogs or groups of dogs from transect lines were obtained in 1088 instances (N = 1278 dogs; mean group SIZE = 1.2). Various functions modelling the probability of detection were fitted to a truncated distribution of distances of dogs from transect lines. A hazard rate model provided the best fit and an overall estimate of dog-population density of 468/km2 (95% confidence interval, 359 to 611). At vaccination, most dogs were marked with either a paint stick or a black plastic collar. Overall, 34.8% of 2167 and 28.5% of 2115 dogs could be accurately identified as wearing a collar or showing a paint mark; 49.1% of the dogs had either mark. Increasing time interval between vaccination-team visit and dog survey and increasing distance from transect line were inversely associated with the probability of observing a paint mark. Probability of observing a collar was positively associated with increasing estimated density of the dog population in a given village and with animals not associated with a house. The data indicate that distance sampling is a relatively simple and adaptable method for estimating dog-population density and is not prone to problems associated with meeting some model assumptions inherent to mark-recapture estimators.  相似文献   
66.
A high prevalence of renal failure has been reported in bull terriers in Australia. The pattern of inheritance was analysed in a family of 33 bull terriers in which 10 dogs had renal disease manifested by proteinuria, ultrastructural abnormalities in the glomerular basement membrane, renal failure, or 'end stage' kidneys. The presence of at least one affected parent for each affected offspring, the approximately equal male/female ratio and the apparent absence of 'generation-skipping', strongly supported an autosomal dominant mode of inheritance, assuming a fully penetrant single major gene locus. Further evidence was not compatible with either an autosomal recessive or X-linked inheritance pattern. This contrasts with the X-linked inheritance shown in Alport's-type human hereditary nephritis and hereditary glomerulopathy in the samoyeds. Hereditary nephritis in the bull terrier should be a useful model for non-Alport's-type human hereditary nephritis, which is also reported to have an autosomal dominant inheritance pattern.  相似文献   
67.
A laboratory feeding trial was conducted to evaluate the effects of reducing digestible energy to protein (DE:P) ratios of practical diets on body fat and weight gain of channel catfish. Five diets were formulated to contain 32, 28, or 24% crude protein with typical DE:P ratios of 8.5, 9.9, or 11.4 kcal/g protein, respectively, and 28% or 24% protein with a reduced DE:P ratio of 8.5 kcal/g protein. Cellulose was used to adjust the DE:P ratio. Juvenile channel catfish Ictalurus punctatus (initial weight: 5.2 g/fish) were fed the experimental diets twice daily to apparent satiation for 12 wk. Fish fed the 28% protein diet with a reduced DE:P ratio of 8.5 kcal/g protein gained less weight and converted feed less efficiently than those fed the 28% protein diet with a typical DE:P ratio of 9.9 kcal/g protein. Fish fed the 24% protein diet with a reduced DE:P ratio of 8.5 kcal/g protein had a similar weight gain but converted feed less efficiently than those fed the 24% protein diet with a typical DE:P ratio of 11.4 kcal/g protein. Weight gain and feed conversion efficiency of fish fed the 32% protein diet with a typical DE:P ratio of 8.5 kcal/g protein were higher than for fish fed other diets except those fed the 28% protein diet with a DE:P ratio of 9.9 kcal/g protein. There were no differences in feed consumption and survival among dietary treatments. Fillet fat of fish fed the 24% and 28% protein diets with a reduced DE:P ratio was lower than that of the fish fed diets containing the same protein concentrations with typical DE:P ratios. At a DE:P ratio of 8.5 kcal/g protein, there were no differences in fillet fat concentration among fish fed diets containing different protein concentrations. There were no differences in fillet protein, moisture, and ash between fish fed the 24% or 28% protein diets containing reduced and typical DE:P ratios. Results from this study show that reducing DE:P ratios in practical diets lowers body fat but also depresses weight gain of channel catfish; thus it would not be economical to use this strategy to reduce body fat of the fish.  相似文献   
68.
A porcine group C rotavirus was found to be the unique cause of a problem of enzootic neonatal diarrhea in a minimal disease herd composed of 190 sows on a continuous farrowing program. During the outbreaks of diarrhea, 10 to 80% of the litters were affected with a morbidity rate of 100% and case fatality rates of 5 to 10%. Clinical signs began 24 to 48 h after birth and were characterized by a profuse yellow diarrhea lasting a few days. Piglets from different outbreaks of diarrhea were necropsied. They had multifocal villous atrophy in the small intestine, especially in the ileum. Group C rotavirus was demonstrated by direct immunofluorescent staining of frozen intestinal sections and by polyacrylamide gel electrophoresis of viral RNA extracted from the intestinal contents of diarrheic piglets. The infection with clinical illness and lesions was reproduced experimentally in newborn piglets by oral inoculation of a suspension prepared from a pool of intestinal contents from diarrheic piglets.  相似文献   
69.
Hypochloremic metabolic alkalosis accompanied by hypokalemia and hyponatremia was induced experimentally in 7 adult sheep by diversion (loss) of gastric contents through an Ivan and Johnston cannula placed in the cranial part of the duodenum just distal to the pylorus. Cannula placement was easily accomplished, and cannulae were tolerated well by the sheep. Volume of effluent produced during the 60- to 120-hour period of diversion ranged from 7.7 to 14.9 L and tended to be greatest during the first 24 hours. All sheep became dehydrated, with mean PCV and plasma total protein concentration increases of 94.2 and 61.7%, respectively. Plasma chloride concentration decreased in linear fashion from a prediversion mean of 113 mEq/L (range, 111 to 117 mEq/L) to an end-point mean of 54 mEq/L (range, 45 to 65 mEq/L). Plasma sodium and potassium concentrations also decreased, though potassium concentration increased terminally. There were rapid increases in arterial blood pH and bicarbonate and base excess concentrations during the first 48 hours after diversion. However, during the final stages of diversion, sheep developed superimposed metabolic acidosis with increased plasma lactate concentration and high anion gap.  相似文献   
70.
The combined use of organic residue and inorganic fertiliser-phosphorus (P) is appropriate in meeting both the short and long-term P requirement of crops. To assess the influence of added inorganic fertiliser-P on the processes of decomposition and P release from the residue and the relationships with quality, prunings of Gliricidia sepium, Leucaena leucocephela, Senna siamea, Acacia mangium and Paraserienthus falcataria were incubated without and with added inorganic fertiliser-P for 56 days. Soil was added only as inoculum. Decomposition rate and amounts of acid extractable-P (P release) were in the same order: G. sepium >S. siamea > L. leucocephela >P. falcataria > A. mangium. Unlike the other residues, A. mangium released no P despite the loss of half its mass during the 8 weeks of incubation. The residue P content correlated with P release. However, decomposition rate did not correlate with residue P content but with the lignin, polyphenol and cellulose content, and ratios to P. These ratios were negatively correlated with P release suggesting that lignin and polyphenol contents influence P release more when the residue-P content is low. Results suggest that rate of decomposition influences the release of P. The critical residue P content for P release was estimated to be 0.12% < P < 0.19%. Added P had no effect on decomposition and P release from the residues.  相似文献   
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