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151.
A total of 578 slaughter pigs from 2 Danish conventional farrow-to-finish operations (Herds A and B) were followed from an age of 14 days to slaughter. Pigs were weighed at 3 weeks intervals and at slaughter and an extended post mortem examination of the plucks was done. Comparison of growth rates in pigs with and without specific types of lesions by the t-test and those with multiple lesions with regression models demonstrated that Mycoplasma-like pneumonia, complicated pneumonia, anterio-ventral pleuritis, fissures and atrophic rhinitis significantly reduced mean daily gain and increased the time required to reach slaughter weight. The total impact of the lesions in Herd A was an estimated reduction in mean daily gain of 27 grams and a 2 day increase in the interval from 14 days of age until slaughter (MDG14). Decreases in MDG14 in Herd B were more substantial, 98 grams and 16.7 days. Reductions in mean daily gains during the interval from the fourth weighing until slaughter were 31 grams in Herd A and 137 grams in Herd B. Chronic dorso-caudal and parietal pleuritis, without other lesions present, had no significant adverse effects on growth rates in either herd. Interactions between lesions did not significantly alter the estimates. The R2 values obtained for the regression models showed that the presence, absence or extent of lesions at slaughter explained only 13-27% of the variations in growth rates in the 2 herds.  相似文献   
152.
A combined ultracentrifugationl/precipitation method for the measurement of lipoprotein cholesterol concentrations was developed and validated for use with canine plasma. Very low density lipoproteins (VLDL) were isolated by flotation ultracentrifugation and low density lipoproteins (LDL) separated from high density lipoproteins (HDL) by precipitation with heparin-manganese chloride. Effective separation of these classes was confirmed by agarose gel electrophoresis of native lipoproteins and by sodium dodecyl sulphate polyacrylamide gel electrophoresis of their apolipoprotein distributions. There was trace contamination of the LDL precipitate with HDL, but this represented less than 4 and 9 per cent of the total plasma HDL in normo- and hypercholesterolaemic dogs, respectively. The intra-assay and interassay coefficients of variation for LDL- and HDL-cholesterol concentrations were between 3·3 and 6·9 per cent, and 7·2 and 9·0 per cent, respectively, for plasma cholesterol concentrations between 2·67 and 8·14 mmoll/litre. The intra-assay coefficient of variation for VLDL-cholesterol was 53·8 and 18·4 per cent at plasma cholesterol concentrations of 2·67 and 8·14 mmol/litre, respectively. The interassay coefficient of variation for VLDL was 22·5 per cent. Storage of plasma at -20°C for between two and eight weeks did not affect VLDL-cholesterol concentrations, but led to an increase in LDL-cholesterol and a decrease in HDL-cholesterol concentrations of approximately 10 per cent. The method described is appropriate for the measurement of lipoprotein concentrations in plasma from normo- and hypercholesterolaemic dogs, but samples should not be subjected to prolonged storage before analysis.  相似文献   
153.
A field study involving 325 calves from 17 dairy herds in Saskatchewan was conducted to determine the risk of enzootic pneumonia and to assess its association with a number of factors. Two different case definitions of pneumonia were used in the analyses: the first was based on producers' treatment risk (CASE1) and the second was based on semimonthly clinical examinations of calves by the research veterinarian (CASE2). The risk of pneumonia based on CASE1 was 39% and on CASE2 was 29%. The measure of agreement between CASE1 and CASE2 at the calf level of analysis was poor (kappa = 0.24, SE = 0.02) and at the herd level of analysis was moderate (kappa = 0.40, SE = 0.12). The mortality risk from pneumonia was 1.8% and a variety of infectious organisms were isolated from pneumonic lungs. Twenty-seven percent of the calves had inadequate (total IgG < or = 800 mg/dL) levels of passively acquired antibodies as measured by radial immunodiffusion. The proportion of seropositive titers in calves within the first two weeks of age was 94% to parainfluenza 3 virus (PI3V) and bovine respiratory syncytial virus (BRSV), 73% to Pasteurella haemolytica (Ph), 68% to bovine viral diarrhea virus (BVDV), 67% to infectious bovine rhinotracheitis virus (IBRV), 46% to Mycoplasma dispar (Md), 44% to Haemophilus somnus (Hs), and 21% to Mycoplasma bovis (Mb). At the calf level of analysis and after adjusting for clustering, there was a negative association (p = 0.10) between the diagnosis of pneumonia based on CASE2 and total IgG levels and Ph titers (rPh).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
154.
As the specialties of emergency medicine and critical care have grown and evolved in both human and veterinary medicine, so has the need for more advanced care of patients with primary lung disease. Treatment of acute respiratory failure has been the focus of several articles in the human medical literature of the past few years.1,8 This paper deals with airway pressure therapy and its application in cases of acute respiratory failure in veterinary medicine. The reader is referred to part I of this paper for a reveiw of respiratory mechanics and hypoxemia as they apply to respiratory therapy.  相似文献   
155.
A 10-year-old castrated domestic shorthair cat received two renal allografts, 14 days apart, for the treatment of chronic renal failure. Oxalate nephrosis developed in both allografts, and they became nonfunctional. During the transplantation period, the cat was not exposed to exogenous sources of oxalate, and there was no evidence of primary type 2 hyperoxaluria before surgery. Urologic surgery, in particular renal transplantation, has been identified as a factor that can precipitate renal failure in human patients with decompensated renal function and hyperoxaluria. If hyperoxaluria was present before surgery in this cat, it was most likely caused by increased absorption or decreased metabolism of dietary oxalate.  相似文献   
156.
Abstract— An objective method for measuring corneocyte numbers before and after antiseborrheic shampoo therapy was assessed in dogs. Corneocytes were collected from six skin regions on the dorsal trunk of nine colony-raised beagles with clinically normal skin. Forty-eight collection sites were randomly assigned a treatment with one of seven medicated shampoos or water alone; six additional sites served as non-treated controls. Corneocytes were collected immediately before the first treatment, and 14 and 28 days after initiation of therapy with a 0.1% Tween 80 surfactant and a quantitative cup-scrub technique. Pretreatment corneocyte counts were not significantly different among the nine dogs nor among the randomly assigned treatment and control sites (3.55 · 104 cells.cm-2, SEM 0.17). Corneocyte counts increased in all treatment and control sites from days 0 to 14. Corneocyte counts were similar in the non-treated and water-treated sites from days 14 to 28. Corneocyte counts were not significantly different when the same treatments were compared on days 0, 14 and 28, or when different treatments were compared on the same day. The corneocyte collection technique used in this study proved to be a reliable method for assessing the rate of cell desquamation and cell surface cohesion in dogs.  相似文献   
157.
158.
The majority of sows return to estrus within 2 weeks after weaning. Swine practitioners attempt to optimize production by reducing the WEI. Some sows fail to resume estrous cyclicity after weaning; however, the endocrinologic pathogenesis of these anestrous sows is speculative. The average WEI is influenced by numerous factors, including season, environmental temperature, photoperiod, nutrition, stress, facility design, lactation length, and management practices. It is evident that the majority of these factors have a more profound influence on primiparous sows than on multiparous sows. Optimum protein and energy consumption by sows during lactation and after weaning and effective utilization of breeding facilities reduce the WEI. The precise roles of photoperiodic changes, elevated environmental temperatures, and stress in seasonal infertility remain poorly understood. Fortunately, current management techniques have reduced the WEI on most farms without instituting therapeutic measures.  相似文献   
159.
The severe fibrinonecrotic pneumonia associated with pneumonic pasteurellosis usually results from colonization of the lower respiratory tract by Pasteurella haemolytica biotype A, serotype 1(A1). Despite recent research efforts, the authors lack a detailed understanding of the interactions and host response to P. haemolytica in the respiratory tract. The authors hypothesize that management and environmental stress factors or viral infection alters the upper respiratory tract (URT) epithelium allowing P. haemolytica to colonize the epithelium. Once the URT is colonized, large numbers of organisms enter the lung where they interact with alveolar macrophages. Endotoxin, released from the bacteria, crosses the alveolar wall where it activates pulmonary intravascular macrophages, endothelium, neutrophils, lymphocytes, platelets, complement, and Hageman factor leading to complex interactions of cells and mediators. It is the progression of this inflammatory response with neutrophil influx that is ultimately responsible for the pulmonary injury. Leukotoxin is a major virulence factor of P. haemolytica that allows it to survive by destroying phagocytic cells. At subcytolytic concentrations it may also enhance the inflammatory response by activating cells to produce mediators and release reactive oxygen metabolites and proteases.  相似文献   
160.
Twenty rabbits were inoculated with a suspension of Viral Hemorrhagic Disease virus. Hemostatic functions were assessed every sixth hour from 6 to 60 hours post-inoculation. Tissue samples obtained at the same intervals allowed the study of the development of lesions throughout the experiment. Biological signs of Disseminated Intravascular Coagulation (DIC) were detected on and after 30 h post-inoculation and consisted of prolonged One Stage Prothrombin Time and Activated Partial Thrombin Time, the decrease of factors V, VII, and X and high levels of soluble fibrin monomer complexes and D-dimers. A reduction of thrombocyte numbers, heterophils and lymphocytes was associated. The close association of DIC and necrotizing hepatitis lesions suggested the hepatic lesions to be the most important DIC triggering factor. Other mechanisms are discussed.  相似文献   
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