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991.
Sivakumar P Sankar M Nambi PA Praveena PE Singh N 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2005,52(10):506-509
The mesenteric lymph nodes (MLN) of buffaloes (n = 100) were examined for the presence of parasitic infection. The nymphal stage of Linguatula serrata was observed in two buffaloes. A single white-coloured nymph with transversely striated spines on a segmented body, two pairs of oral suckers and hooks was observed in the MLN. The morphometrics of the nymphs were studied. The affected lymph nodes were grossly enlarged with cyst and showed pathological lesions of fibroblastic reaction with a mild underlying inflammatory zone. 相似文献
992.
The existence of a temperature gradient between the testis and deep body temperature has been accepted for many years. It is based on two simultaneous principles: cooling of the testis through the scrotal wall and transfer of heat between the testicular blood vessels. The ovary is positioned in the abdomen; a temperature difference parallel to the male system therefore seems less likely. However, the temperature of large follicles has been found to be 0.5 to 1.5 degrees C cooler than the ovarian stroma in rabbits, pigs and, probably, women. The temperature difference seems to be based on a heat-consuming process in the expanding follicullar fluid, and a local transfer of heat between intra-ovarian blood vessels. The reason for the temperature gradient is not yet known; one may speculate of a common reason for the cooling of the gamete in male and female. 相似文献
993.
Maass N Bauer J Paulicks BR Böhmer BM Roth-Maier DA 《Journal of animal physiology and animal nutrition》2005,89(7-8):244-252
The aim of the present investigation was to examine the inclusion of the dried herb Echinacea purpurea (L.) MOENCH as feed additive in diets of sows, piglets, and grower/finisher pigs on growth performance, blood picture, plasma enzymes including proliferation of lymphocytes, antibody status, and protein and immune globulin content of colostrum. The control groups were supplemented with alfalfa meal. The sows (total 36) received 0%, 1.2%, or 3.6% Echinacea cobs in the diet from day 85 to day 110 of gestation and 0%, 0.5%, or 1.5% Echinacea cobs up to day 28 of lactation. No significant differences were found for growth performance, weight loss, blood picture, plasma enzymes, and colostrum composition. Performance of the sucking piglets was not impaired either during lactation or during a 4 week observation period after weaning. The health status was similar in all treatment groups. In a second experiment, lasting 6 weeks, with 36 piglets (5.8-22.1 kg body weight), 1.8% Echinacea cobs, or 20 mg/kg feed Flavomycin were supplemented. No significant differences were found for the recorded parameters. Feed conversion ratio (kg feed/kg gain) of the Echinacea group was slightly (4%) increased (1.54 vs. 1.60). In a third trial, 48 grower/finisher pigs were used during a 9-week experimental period with two supplementation phases (weeks 1-3 and weeks 7-9). The experimental groups received 0%, 1.5% cobs or 4-6 ml pressed juice (commercial standard) per day respectively. Vaccination with Swine erysipelas was implemented in weeks 1 and 5 to determine the specific immune response. Growth performance and blood picture for all groups were similar, however, feed conversion of both Echinacea supplemented groups was significantly (p < 0.03) better than of the unsupplemented control group (2.44 vs. 2.51). In addition, the Swine erysipelas antibodies showed a marked significance (p < 0.05) in regard of altitude in both supplemented groups. It is concluded, that E. purpurea might be used as a feed additive to achieve immune stimulating efficiency in pig production and increase feed-to-gain-conversion. The efficiency of cobs is comparable to a commercial juice product. 相似文献
994.
Acral mutilation and analgesia (AMA) is reported in 13 French spaniels in Canada. This newly recognized disorder shares striking similarities in clinical features and biopsy findings to the other acral mutilation syndromes or hereditary sensory neuropathies reported in German short-haired pointer dogs, English pointer dogs and English springer spaniels. Clinical signs are first noted between 3.5 and 12 months of age. Affected dogs lick, bite and severely self-mutilate their distal extremities resulting in ulcers with secondary bacterial infection. Auto-amputation of claws, digits and footpads occurs in severe cases. Single or multiple feet can be affected. Affected dogs walked on their severely mutilated feet without evidence of pain, lameness, or ataxia. The majority of the dogs were euthanized within days to months of diagnosis. 相似文献
995.
A spatial analysis was carried out in order to analyse the reason why the risk of Bovine Spongiform Encephalopathy (BSE) was spatially heterogeneous in France, during the period following the feed ban of Meat and Bone Meal to cattle. The hypothesis of cross-contamination between cattle feedstuff and monogastric feedstuff, which was strongly suggested from previous investigations, was assessed, with the assumption that the higher the pig or poultry density is in a given area, the higher the risk of cross-contamination and cattle infection might be. The data concerned the 467 BSE cases born in France after the ban of meat and bone meal (July 1990) and detected between July 1st, 2001 and December 31, 2003, when the surveillance system was optimal and not spatially biased. The disease mapping models were elaborated with the Bayesian graphical modelling methods and based on a Poisson distribution with spatial smoothing (hierarchical approach) and covariates. The parameters were estimated by a Markov Chain Monte Carlo simulation method. The main result was that the poultry density did not significantly influence the risk of BSE whereas the pig density was significantly associated with an increase in the risk of 2.4% per 10 000 pigs. The areas with a significant pig effect were located in regions with a high pig density as well as a high ratio of pigs to cattle. Despite the absence of a global effect of poultry density on the BSE risk, some areas had a significant poultry effect and the risk was better explained in some others when considering both pig and poultry densities. These findings were in agreement with the hypothesis of cross-contamination, which could take place at the feedstuff factory, during the shipment of food or on the farm. Further studies are needed to more precisely explore how the cross-contamination happened. 相似文献
996.
ABSTRACT Multilocus haplotypes (MLHs) were derived for the spermogonial (monokaryotic haploid) stage of Cronartium ribicola, the causal agent of white pine blister rust. Six random amplified polymorphic DNA loci and three single-strand conformational polymorphism markers were analyzed for 246 rust samples collected from two heavily infected white pine plantations. All cankers sampled were spatially located within the plantations. The hypothesis that spores are not locally disseminated was supported by the absence of any spatial clustering in the distribution of the MLHs. A large number of MLHs was found at both sites and the haplotypic diversity was close to the maximum (one) in both populations. All measures of recombination were not different from expectations under a scenario of sexual recombination. Genetic differentiation between the two sites was very low (theta = 0.023), yet it was significantly different from zero (P < 0.01). This analysis is in agreement with a scenario of extensive sexual recombination followed by some long-distance dispersal. 相似文献
997.
ABSTRACT Mapping and analyzing the disease status of individual plants within a study area at successive dates can give insight into the processes involved in the spread of a disease. We propose a permutation method to analyze such spatiotemporal maps of binary data (healthy or diseased plants) in regularly spaced plantings. It requires little prior information on the causes of disease spread and handles missing plants and censored data. A Monte Carlo test is used to assess whether the location of newly diseased plants is independent of the location of previously diseased plants. The test takes account of the significant spatial structures at each date in order to separate nonrandomness caused by the structure at one date from nonrandomness caused by the dependence between newly diseased plants and previously diseased plants. If there is a nonrandom structure at both dates, independent patterns are simulated by randomly shifting the entire pattern observed at the second date. Otherwise, independent patterns are simulated by randomly reallocating the positions of one group of diseased plants. Simulated and observed patterns of disease are then compared through distance-based statistics. The performance of the method and its robustness are evaluated by its ability to accurately identify simulated independent and dependent bivariate point patterns. Additionally, two realworld spatiotemporal maps with contrasting disease progress illustrate how the tests can provide valuable clues about the processes of disease spread. This method can supplement biological investigations and be used as an exploratory step before developing a specific mechanistic model. 相似文献
998.
999.
Frank N Sommardahl CS Eiler H Webb LL Denhart JW Boston RC 《American journal of veterinary research》2005,66(6):1032-1038
OBJECTIVE: To evaluate glucose and lipid metabolism in healthy adult horses administered levothyroxine sodium (L-T4). ANIMALS: 12 healthy adult mares. PROCEDURE: 8 horses received an incrementally increasing dosage of L-T4 (24, 48, 72, or 96 mg of L-T4/d) for weeks 1 to 8. Each dose was provide between 7 AM and 8 AM in the morning grain meal for 2 weeks. Four additional horses remained untreated. Serum concentrations of nonesterified fatty acids, triglyceride (TG), total cholesterol (TC), and very-low-density lipoprotein (VLDL) were measured and composition of VLDL examined in samples obtained between 8 AM and 9 AM at weeks 0, 2, 4, 6, and 8. Glucose dynamics were assessed by use of a combined IV glucose-insulin tolerance test (IVGITT) conducted before and at the end of the 8-week treatment period. Data for each combined IVGITT were interpreted by use of the minimal model. RESULTS: Plasma TG, TC, and VLDL concentrations significantly decreased over time in treated horses. At the completion of the 8-week treatment period, mean plasma VLDL concentration was 46% of the mean value for week 0 in treated horses. Insulin sensitivity significantly increased (> 2-fold) in treated horses, but glucose effectiveness and net insulin response were not affected. Levothyroxine sodium significantly increased the rate of insulin disposal. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of L-T4 decreases blood lipid concentrations, improves insulin sensitivity, and increases insulin disposal in horses. Levothyroxine sodium may have potential as a treatment for horses with reduced insulin sensitivity. 相似文献
1000.
Eiler H Frank N Andrews FM Oliver JW Fecteau KA 《American journal of veterinary research》2005,66(9):1598-1604
OBJECTIVE: To characterize the physiologic response to i.v. bolus injection of glucose and insulin for development of a combined glucose-insulin test (CGIT) in horses. ANIMALS: 6 healthy mares and 1 mare each with pituitary adenoma and urolithiasis. PROCEDURE: Horses were given a CGIT (glucose, 150 mg/kg; insulin, 0.1 U/kg); results were compared with a singular i.v. glucose tolerance test (GTT; 150 mg/kg) and a singular i.v. insulin sensitivity test (IST; 0.1 U/kg). Healthy horses were also given a CGIT after receiving xylazine and undergoing stress. RESULTS: Physiologically, the CGIT resulted in a 2-phase curve with positive (hyperglycemic) and negative (hypoglycemic) portions; the positive phase came first (250% of baseline at 1 minute). The descending segment declined linearly to baseline by approximately 30 minutes and to a nadir at 58% of baseline by 75 minutes. After a 35-minute valley, a linear ascent to baseline began. Addition of insulin in the CGIT increased glucose utilization by approximately 4.5 times during the positive phase but not during the negative phase. The diseases' effects and experimental inhibition of insulin secretion with xylazine and stress were detectable by use of the 2 phases of the CGIT. Only a single positive phase resulted from the GTT and a single negative phase from the IST CONCLUSIONS AND CLINICAL RELEVANCE: The CGIT resulted in a consistent, well-defined glycemia profile, which can be disrupted experimentally or by a disease process. The CGIT has clinical potential because it provides integrated information and more information than either the singular GTT or IST. 相似文献