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91.
Effects of recombinant porcine somatotropin (rpST) on metabolic rate were studied in two trials with 24 crossbred barrows (Yorkshire x Landrace) in each. The barrows weighed about 80 kg (SE within trials 2.2 kg) at the start of the measurements and in each trial 12 pigs received 4 mg of rpST and 12 received a placebo. The diet contained 2.57 Mcal NE/kg and 20% CP (about 1% lysine). Animals were fed approximately 2.8 times maintenance (280 kcal ME.kg-.75.d-1). Heat production (gaseous exchange of CO2 and O2) and activity were measured continuously. Heat production associated with activity was calculated from the regression of heat production on activity. Animals treated with rpST exceeded controls in rate of gain by 252 g/d (P less than .001) and in metabolic rate by 14.5 kcal.kg-.75.d-1 (P less than .01). The rpST treatment increased rectal (+ .2 degrees C) and surface (+ .8 degrees C) temperatures. Activity-related heat production in treated pigs was increased, but this was only partly related to the increase in metabolic rate with rpST. The daily patterns of total and activity-related heat production were similar between pigs in both experimental treatments.  相似文献   
92.
A randomized, placebo-controlled, four-period cross-over laboratory study involving eight dogs was conducted to confirm the effective analgesic dose of firocoxib, a selective COX-2 inhibitor, in a synovitis model of arthritis. Firocoxib was compared to vedaprofen and carprofen, and the effect, defined as a change in weight bearing measured via peak ground reaction, was evaluated at treatment dose levels. A lameness score on a five point scale was also assigned to the affected limb. Peak vertical ground reaction force was considered to be the most relevant measurement in this study. The firocoxib treatment group performed significantly better than placebo at the 3 h post-treatment time point and significantly better than placebo and carprofen at the 7 h post-treatment time point. Improvement in lameness score was also significantly better in the dogs treated with firocoxib than placebo and carprofen at both the 3 and 7 h post-treatment time points.  相似文献   
93.
Blood lactate measurements are commonly used in exercising horses to determine the onset of lactate accumulation and in colic patients to assess clinical status and to indicate prognosis. To study the usability of a portable blood lactate meter based on dry chemistry (Lactate Pro), the data from this instrument were compared to data from a laboratory-used lactate meter based on wet chemistry (ABL 605 blood gas analyzer [ABL]). Heparinized blood samples were obtained from horses participating in a jumping experiment (n = 9), from horses cantering at maximal speed on a racetrack (n = 7), and from patients admitted to the Department of Equine Sciences at Utrecht University for severe colic (n = 13). Seventeen of these samples were tested in duplicate on both instruments to determine the repeatability of the measurements. Blood lactate concentrations measured with the Lactate Pro ranged from 0.8-17.6 mmol/liter and with the ABL from 1.0-18.6 mmol/liter. The correlation between lactate concentrations obtained using the Lactate Pro and values from the ABL was 0.90, and the relationship was represented by the following formula: y = 0.90 . x + 0.36, indicating a linear relationship between values produced by the ABL and Lactate Pro. The repeatability for the Lactate Pro was high (0.997), which is comparable to the ABL (0.999).  相似文献   
94.
Spirocerca lupi is a nematode infesting the canine oesophagus, where it induces the formation of a nodule that may transform into a malignant sarcoma. The current, retrospective study compared the clinical presentation, haematology, serum albumin and globulin and radiology of benign cases (n=31) and malignant cases (n=31) of spirocercosis. Dogs with spirocercosis-induced sarcoma were significantly older (6.4+/-1.91 years) than benign cases (4.93+/-2.87). In the malignant cases there were significantly (p=0.03) more sterilized females (10/31) and fewer intact males (4/31) compared to 2/31 and 13/31, respectively, in the benign cases. Hypertrophic osteopathy was observed in 38.7% of malignant cases and in none of the benign cases (p=0.0002). Common clinical signs included weight loss, regurgitation, anorexia, pyrexia (T>or=39.5 degrees ), respiratory complications and salivation but did not differ in prevalence between groups. On haematology, the malignant group had significantly (p<0.05) lower haematocrit (0.34+/-0.08 vs. 0.41+/-0.07) and higher white cell count (31.6+/-27.83 vs. 17.71+/-13.18 x 10(3)microl(-1)), mature neutrophil count (26.06+/-26.08 vs. 12.23+/-9.96 x 10(3)microl(-1)) and thrombocyte count (493.15+/-151.61 vs. 313.27+/-128.54 x 10(9)microl(-1)). There were no differences in the mean corpuscular volume and immature neutrophil count. On radiology, the mass length was not significantly different, but the height and the width of the malignant masses were significantly larger (62.59+/-15.15 mm and 73.93+/-20.94 mm) compared to the benign group (46.43+/-23.62 and 49.29+/-25.56, respectively). Spondylitis was more prevalent in the malignant group (67.86% vs. 38.46%, p=0.03). Examining secondary pulmonary changes revealed significantly higher prevalence of bronchial displacement in the malignant group (52% vs. 17%, p=0.008). Hypertrophic osteopathy appeared to be a very specific but relatively rare (poor sensitivity) marker of malignancy. Female gender, anaemia, leukocytosis, thrombocytosis, spondylitis and bronchial displacement are significantly more common in malignant cases, but appear in benign cases as well. However, if found together in a specific case, they should increase the index of suspicion for malignancy in a diagnosed spirocercosis case.  相似文献   
95.
The Netherlands has enjoyed a relatively free state of vector-borne diseases of economic importance for more than one century. Emerging infectious diseases may change this situation, threatening the health of humans, domestic livestock and wildlife. In order to be prepared for the potential outbreak of vector-borne diseases, a study was undertaken to investigate the distribution and seasonal dynamics of candidate vectors of infectious diseases with emphasis on bluetongue vectors (Culicoides spp.). The study focused primarily on the relationship between characteristic ecosystems suitable for bluetongue vectors and climate, as well as on the phenology and population dynamics of these vectors. Twelve locations were selected, distributed over four distinct habitats: a wetland area, three riverine systems, four peat land areas and four livestock farms. Culicoides populations were sampled continuously using CO(2)-baited counterflow traps from July 2005 until August 2006, with an interruption from November 2005 to March 2006. All vectors were identified to species level. Meteorological and environmental data were collected at each location. Culicoides species were found in all four different habitat types studied. Wetland areas and peat bogs were rich in Culicoides spp. The taxonomic groups Culicoides obsoletus (Meigen) and Culicoides pulicaris (Linnaeus) were strongly associated with farms. Eighty-eight percent of all Culicoides consisted of the taxon C. obsoletus/Culicoides scoticus. On the livestock farms, 3% of Culicoides existed of the alleged bluetongue vector Culicoides dewulfi Goetghebuer. Culicoides impunctatus Goetghebuer was strongly associated with wetland and peat bog. Many Culicoides species were found until late in the phenological season and their activity was strongly associated with climate throughout the year. High annual variations in population dynamics were observed within the same study areas, which were probably caused by annual variations in environmental conditions. The study demonstrates that candidate vectors of bluetongue virus are present in natural and livestock-farm habitats in the Netherlands, distributed widely across the country. Under favourable climatic conditions, following virus introduction, bluetongue can spread among livestock (cattle, sheep and goats), depending on the nature of the viral serotype. The question now arises whether the virus can survive the winter conditions in north-western Europe and whether measures can be taken that effectively halt further spread of the disease.  相似文献   
96.
Colibacillosis results from infection with avian pathogenic Escherichia coli bacteria. Healthy broilers are resistant to inhaled E. coli, but previous infection with vaccine or virulent strains of Infectious Bronchitis Virus (IBV) predisposes birds for severe colibacillosis. We investigated whether IBV affects recruitment and function of phagocytic cells and examined NO production, phagocytic and bactericidal activity, and kinetics of peripheral blood mononuclear cells (PBMC) and splenocytes. Moreover, we measured cytokine mRNA expression in lung and spleen samples. Broilers were inoculated with IBV H120 vaccine or virulent M41 and challenged 5 days later with E. coli 506. A PBS control and E. coli group without previous virus inoculation were also included. Birds were sacrificed at various time points after inoculation (h/dpi). Inoculation with IBV induced extended and more severe colibacillosis than with E. coli alone. At 4dpi, the number of KUL-01(+) PBMC in all E. coli-inoculated groups was significantly higher than in PBS-inoculated birds, which correlated with lesion scores. From 1 to 4dpi, NO production by PBMC from all E. coli-inoculated animals was elevated compared to PBS birds. Bactericidal activity of PBMC in IBV-inoculated animals at 7dpi was lower than in PBS- and E. coli-inoculated birds, but phagocytic capacity and recruitment were not severely impaired. In spleen samples of IBV-infected animals reduced expression of IL-1beta, IL-6, IL-8, IL-10, IL-18 and IFN-gamma mRNA was found 1dpi. Our results suggest that enhanced colibacillosis after IBV infection or vaccination is caused at least by altered innate immunity and less by impairment of phagocytic cell function.  相似文献   
97.
Background: The endocrine diagnosis of primary hyperaldosteronism in cats currently is based on an increased plasma aldosterone to renin ratio, which has several disadvantages for use in veterinary practice. Objectives: To establish a reference range for the urinary aldosterone to creatinine ratio (UACR) and to determine whether oral administration of either sodium chloride or fludrocortisone acetate is effective for use in a suppression test. Animals: Forty‐two healthy cats from an animal shelter and 1 cat with primary hyperaldosteronism from a veterinary teaching hospital. Methods: Morning urine samples for determination of the basal UACR were collected from 42 healthy cats. For the suppression tests, urine samples for the UACR were collected after twice daily oral administration for 4 consecutive days of either sodium chloride, 0.25 g/kg body weight (n = 22) or fludrocortisone acetate, 0.05 mg/kg body weight (n = 15). Results: The median basal UACR was 7.2 × 10?9 (range, 1.8–52.3 × 10?9), with a calculated reference range of <46.5 × 10?9. Administration of sodium chloride resulted in adequate salt loading in 10 of 22 cats, but without significant reduction in the UACR. Administration of fludrocortisone resulted in a significant decrease in the UACR (median, 78%; range, 44–97%; P < .001) in healthy cats. In the cat with an aldosterone‐producing adrenocortical carcinoma, the basal UACR and the UACR after fludrocortisone administration were 32 × 10?9 and 36 × 10?9, respectively. Conclusions and Clinical Importance: Using the UACR for an oral fludrocortisone suppression test may be useful for the diagnosis of primary hyperaldosteronism in cats.  相似文献   
98.
OBJECTIVE: To assess the effects of age and joint disease on hydroxyproline and glycosaminoglycan (GAG) concentrations in synovial fluid from the metacarpophalangeal joint of horses and evaluate the association of those concentrations with severity of osteoarthritis and general matrix metalloproteinase (MMP) activity. SAMPLE POPULATION: Synovial fluid was collected from the metacarpophalangeal joints of foals at birth (n = 10), 5-month-old foals (10), 11-month-old foals (5), and adult horses (73). PROCEDURE: Hydroxyproline and GAG concentrations were determined in synovial fluid samples. The severity of osteoarthritis in adult joints was quantified by use of a cartilage degeneration index (CDI) and assessment of general MMP-activity via a fluorogenic assay. RESULTS: Hydroxyproline and GAG concentrations in synovial fluid were highest in neonates and decreased with age. Concentrations reached a plateau in adults by 4 years and remained constant in healthy joints. In synovial fluid from osteoarthritic joints, hydroxyproline and GAG concentrations were not increased, compared with unaffected joints, but hydroxyproline were significantly correlated with the CDI and general MMP activity. There was no significant correlation between GAG concentration and CDI value or MMP activity. CONCLUSIONS AND CLINICAL RELEVANCE: Changes in hydroxyproline concentration in synovial fluid appeared to indicate damage to collagen of the articular cartilage. In joints with osteoarthritis, the lack of high GAG concentration in synovial fluid and the absence of a significant correlation between GAG concentration and CDI values or MMP activity may severely limit the usefulness of this marker for monitoring equine joint disease.  相似文献   
99.
Our group developed a genetic-counselling program for boxer-dog breeders in The Netherlands, using data for cryptorchidism (uni- and/or bilateral), epilepsy, knee-problems (including ligament rupture, fractured or ruptured meniscus, severe osteo-arthrosis of the knee, or a combination of these disorders), and schisis (including cheiloschisis, palatoschisis, or cheilopalatoschisis). We transformed the estimated breeding values (EBVs) into odds ratios (ORs), to enable the breeder to compare the risk for each of the traits for a certain dam-sire combination with the average population risk (set at 1). The goal of the study was to evaluate the use of our genetic-counselling program by Dutch breeders of boxer dogs. We asked breeders of the Dutch Boxer Club to send in an application form for genetic-counselling from June 1 to December 1, 2000. Breeders indicated on this application form three desirable sires for their dam (sire 1, sire 2, sire 3) in random order. On the basis of this information, a counselling report was produced which included ORs for the four diseases in litters of the dam-sire combinations indicated on the application form. Together with the counselling report, the breeders received an evaluation form. We received 129 application forms from 70 breeders, and collected 125 evaluations. Of these evaluations, 96 were informative about the influence of the counselling report on sire choice. The most-important criteria used by breeders to select sires were: the exterior characteristics (60%) and known progeny (52%). Although it was the first time breeders could make use of genetic-counselling, 32% of the breeders indicated that the genetic-counselling played a major role in their sire selection. Breeders expressed little difference in importance for the four genetic traits, but there was a tendency to consider epilepsy more than the others. Breeders hesitated to put long-term population interest above short-term personal interest. Nevertheless, the general conclusion of this study is that breeders acknowledge the value of counselling, especially to reduce the frequency of a threatening disease such as epilepsy.  相似文献   
100.
To examine the effect of recombinant bovine interferon-gamma (rbIFN-gamma) on cattle persistently infected with bovine leukemia virus (BLV), BLV-infected cattle were inoculated intraperitoneally with IFN-gamma. All cattle were febrile after inoculation with IFN-gamma and then recovered within 48 h. Flow cytometric analysis showed that the numbers of CD4+ and CD8+ T cells were decreased for 2-3 days and then their numbers were recovered. The number of gammadelta T cells increased after the fever. In contrast, the number of IgM+ lymphocytes remained low for about 1 week. Moreover, the numbers of syncytia produced by peripheral blood lymphocytes decreased and remained low compared to that before IFN-gamma administration. These results suggest that IFN-gamma induces the up-regulation of gammadelta T cells, decreases the number of IgM+ lymphocytes and suppresses the growth of BLV in BLV-infected cattle in vivo.  相似文献   
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