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31.
OBJECTIVE: To assess the effects of dietary modification on clinical signs of exocrine pancreatic insufficiency (EPI) in dogs. DESIGN: Blinded randomized crossover study. ANIMALS: 21 dogs with EPI. PROCEDURE: Dogs were fed the diet they received at home for 2 weeks. Thereafter, they received 3 special diets (a high-fat diet, a high-fiber diet, and a highly digestible low-residue diet) for 3 weeks each. Owners scored dogs daily for the last 2 weeks of each 3-week period for severity of 6 clinical signs including appetite, defecation frequency, consistency of feces, borborygmus, flatulence, and coprophagia. An EPI index was calculated for each dog by adding the daily scores for each clinical sign. RESULTS: Significant differences in daily EPI indices among diets were observed in 20 dogs. The original diet appeared to be the most suitable in 8 dogs, whereas the high-fat diet was most suitable in 5 dogs, the high-fiber diet was most suitable in 4 dogs, and the low-residue diet was most suitable in 2 dogs. In 1 dog, the lowest EPI index score was the same during the original diet and the high-fat diet feeding periods. One dog did not complete the feeding period for the high-fiber diet. Differences in mean EPI indices among diets were not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that responses to different diets varied among individual dogs. Because responses to the feeding regimens were unpredictable, it is suggested that feeding regimens be individually formulated for dogs with EPI.  相似文献   
32.
OBJECTIVE: To determine clinical signs and clinicopathologic abnormalities in dogs with naturally occurring clinical spirocercosis. DESIGN: Retrospective case series. ANIMALS: 39 dogs with spirocercosis. PROCEDURES: Medical records were reviewed, and information on signalment, residence (rural vs urban), owner complaints, physical examination findings, clinicopathologic abnormalities, radiographic and endoscopic findings, and concurrent systemic diseases was recorded. RESULTS: Hellenic hounds and mixed-breed dogs were overrepresented, compared with a group of 117 control dogs without spirocercosis that were examined because of gastrointestinal tract disease, and mean body weight of dogs with spirocercosis was significantly higher than mean body weight of control dogs. Odynophagia (34 [87%]), regurgitation (24 [62%]), and excessive salivation (14 [36%]) were the most common clinical findings. The most common radiographic abnormalities were a mass in the caudodorsal aspect of the mediastinum (15/35 [43%]) and spondylitis of the caudal thoracic vertebrae (10 [29%]). Parasitic nodules were seen during esophagoscopy in all 39 dogs. Normocytic, normochromic, nonregenerative anemia; neutrophilic leukocytosis; hyperproteinemia; and high alkaline phosphatase activity were significantly more common in dogs with spirocercosis than in a control group of 56 healthy dogs. Concurrent systemic diseases, mainly leishmaniosis, dirofilariosis, and monocytic ehrlichiosis, were documented in 14 (36%) dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that clinical spirocercosis occurs more often in young-adult, large-breed dogs. Nonregenerative anemia, neutrophilic leukocytosis, hyperproteinemia, and high alkaline phosphatase activity may be useful clinicopathologic indicators of this disease.  相似文献   
33.
This overview summarizes research performed during the last decades that has had an impact on the diagnosis and management of exocrine pancreatic insufficiency (EPI) in dogs. Pancreatic acinar atrophy is by far the most common cause for the maldigestion signs of canine EPI. The ability to diagnose pancreatic acinar atrophy in the subclinical phase before the development of total acinar atrophy and manifestation of clinical signs has offered new possibilities to study the pathogenesis of the disease. Diagnosis of exocrine pancreatic dysfunction is based on typical findings in clinical histories and clinical signs and is confirmed with pancreatic function tests. In recent years, the measurement of serum canine trypsin-like immunoreactivity has become the most commonly used pancreatic function test to diagnose canine EPI. Serum trypsin-like immunoreactivity measurement is species- and pancreas-specific. When clinical maldigestion signs of EPI appear, enzyme replacement therapy is indicated. Despite accurate enzyme supplementation, only a small portion of orally administered enzymes are delivered functionally intact into the small intestine. In dogs, the highest enzyme activity in the duodenum has been obtained with nonenteric-coated supplements: raw chopped pancreas or powdered enzymes. Aside from dietary enzyme supplements, dietary changes are often made to improve clinical response, but sometimes weight gain and stool quality remain suboptimal. Other medications for treatment of gastrointestinal tract signs are often used in such dogs with EPI. Antibiotics are the most common adjunctive medication. Of the antibiotics administered, tylosin is used in Finland almost exclusively.  相似文献   
34.
Agricultural technological improvements are crucial to increase on farm production and thereby reduce poverty. However the use of improper identification strategies on the impacts of improved technologies on farmer welfare could potentially pose a threat to good practice agricultural policy making. In this study, propensity matching strategies and endogenous switching regression were used to test whether an improved fallow, a soil fertility improving technology that passed the requirements for a high impact intervention based on non randomised impact assessment methodologies could still pass this test. Using data from 324 randomly surveyed households in Chongwe district of Zambia, the rigorous econometric methods confirmed the positive impact of improved fallows on household maize yields, maize productivity, per capita maize yield and maize income. Conflicting results were obtained when a broader welfare indicator—per capita crop income, was considered. Whereas the non-randomised and kernel matching methods showed that per capita crop incomes were significantly higher for the adopters than for the non adopters, the causal effect of improved fallows on this variable was non significant when nearest neighbour matching strategy and the more robust endogenous switching regression were used. It was concluded that the technology improves welfare through increased maize and hence increased food security, and through incomes from the maize crop. The maize income derived from improved fallows were however not sufficient enough to drive the general crop income to significantly higher levels. The need to diversify the use of improved fallows on high valued crops was recommended while the importance of using better and more robust methodologies in evaluating impact of interventions was emphasised.  相似文献   
35.
Myoglobin (Mb) and its iron have been proposed to be major prooxidants in cooked meats. To understand the mechanisms and differentiate between the prooxidant and antioxidant potential of oxymyoglobin (OxyMb) and metmyoglobin (MetMb), their prooxidant activity, iron content, solubility, free radical scavenging activity, and iron binding capacity were determined as a function of thermal processing. The ability of native and heat denatured OxyMb and MetMb to promote the oxidation of muscle microsomes was different. MetMb promoted lipid oxidation in both its native and denatured states. Conversely, OxyMb became antioxidative when the protein was heated to temperatures >or=75 degrees C. The increased antioxidant activity of heat denatured OxyMb was likely due to a decrease in its prooxidative activity due to its loss of solubility. These data show that the impact on oxidative reactions of Mb is the result of the balance between its antioxidant and prooxidant activities.  相似文献   
36.
Thelazia anolabiata is a spirurid nematode living in the orbits of birds which can cause lacrimation, keratitis, conjunctivitis, and corneal ulcers. This species is reported for the first time from an Andean Cock of the Rock, Rupicola peruviana (Passeriformes: Cotingidae), from a zoo in Lima, Peru. Clinical signs of keratoconjunctivitis were resolved with the treatment of ivermectin, ciprofloxacin, and an epithelium regenerator, and the host is presently in good health. The nematodes were identified using the primary characteristics used to differentiate the species of this genus as lengths of spicules and other morphologic characteristics.  相似文献   
37.
Limited information is available about the prevalence and phylogenetic classification of fungal organisms in the gastrointestinal tract of dogs. Also, the impact of fungal organisms on gastrointestinal health and disease is not well understood. The aim of this study was to evaluate the prevalence of fungal DNA in the small intestine of healthy dogs and dogs with chronic enteropathies. Small intestinal content was analyzed from 64 healthy and 71 diseased dogs from five different geographic locations in Europe and the USA. Fungal DNA was amplified with panfungal primers targeting the internal transcriber spacer (ITS) region. PCR amplicons were subjected to phylogenetic analysis. Fungal DNA was detected in 60.9% of healthy dogs and in 76.1% of dogs with chronic enteropathies. This prevalence was not significantly different between the two groups (p=0.065). Fungal DNA was significantly more prevalent in mucosal brush samples (82.8%) than in luminal samples (42.9%; p=0.002). Sequencing results revealed a total of 51 different phylotypes. All sequences belonged to two phyla and were classified as either Ascomycota (32 phylotypes) or Basidiomycota (19 phylotypes). Three major classes were identified: Saccharomycetes, Dothideomycetes, and Hymenomycetes. The most commonly observed sequences were classified as Pichia spp., Cryptococcus spp., Candida spp., and Trichosporon spp. Species believed to be clinically more important were more commonly observed in diseased dogs. These results indicate a high prevalence and diversity of fungal DNA in the small intestine of both healthy dogs and dogs with chronic enteropathies. The canine gastrointestinal tract of diseased dogs may harbor opportunistic fungal pathogens.  相似文献   
38.
East Coast fever (ECF) is a highly fatal lymphoproliferative disease of cattle caused by Theileria parva, a tick-borne intracellular apicomplexan parasite. Parasite antigens that are targets of protective cytotoxic T lymphocyte (CTL) responses are required to formulate a sub-unit vaccine against ECF. A number of CTL target antigens have recently been identified and initial evaluation has shown their vaccine potential. This study aimed to evaluate whether these antigens were recognised by CTL obtained from six genetically diverse Zebu cattle immunized with a cocktail of T. parva stocks. T. parva Muguga specific polyclonal CD8(+) CTL lines were generated and confirmed to specifically lyse autologous infected cells. CTL recognition of autologous skin fibroblasts (iSF) transduced with recombinant modified vaccinia virus Ankara strain (MVA) expressing previously identified T. parva Muguga vaccine candidate antigens was evaluated using an IFN-gamma ELISpot assay. CTL lines from one of the four calves, BY120, responded specifically to cells infected with MVA expressing the antigen Tp2 and synthetic peptides were employed to map a new CTL epitope on this antigen. Immunoscreening of the T. parva genome with these CTL lines should identify novel antigens that will constitute valuable additions to the vaccine candidates currently being evaluated.  相似文献   
39.
The macroscopic features of the arterial supply to the reproductive system of the male ostrich was studied in 16 pre-pubertal and eight sexually mature and active birds. The left and right cranial renal arteries arise from the aorta, between the cranial divisions of the kidneys. These vessels supply the cranial divisions of the kidneys, the testes, the epididymides and the cranial segments of the ducti deferentia. Accessory testicular arteries which arise directly from the aorta are present in 45.8% of the specimens. They supply the testes and cranial parts of the ducti deferentia. They are variable in number and origin, and four variants are identified. A cranial ureterodeferential branch originates from the cranial renal artery, supplies the cranial portion of the ductus deferens and ureter, and runs caudally to anastomose with the middle renal artery. The sciatic artery arises laterally from the aorta, just caudal to the acetabulum, and gives rise, ventrally, to a common trunk, the common renal artery, which divides into the middle and caudal renal arteries. The middle renal artery gives rise to the middle ureterodeferential branch which supplies the middle part of the ductus deferens and ureter. A few centimetres caudal to the kidney, the aorta terminates in three branches, namely, the left and right internal iliac arteries and the median caudal artery. The internal iliac artery divides into the lateral caudal artery and the pudendal artery; the latter gives off caudal ureterodeferential branches that supply the caudal segments of the ductus deferens and ureter. In addition, the pudendal artery gives off vessels that supply the cloaca, some of which continue to the base of the phallus, where they form an arterial network. In conclusion, the pattern of the blood supply to the reproductive organs of the male ostrich is, in general, similar to that of the domestic fowl and pigeon, although there are a few highlighted distinctive features.  相似文献   
40.
Two experiments were conducted to determine the effects of phytase on growth, apparent phosphorus (P), calcium (Ca), iron (Fe), zinc (Zn), magnesium (Mg), and copper (Cu) absorption, and apparent protein digestibility by striped bass Morone saxatills fed a high phytate diet. In experiment one, four diets with graded levels of phytase supplementation, 0, 500, 1,000, and 2,000 phytase units/kg of diet (PUkg), and a diet supplemented with inorganic P (positive control, total P, 0.73%; phytin P, 0.35%) were assigned to duplicate tanks, and were fed to fingerling striped bass for 16 wk. A digestibility trial was conducted at weeks 16–18, using 0.5% Cr2O3 as an indigestible marker in the diets. Phytase was sprayed post-extrusion on the basal diet (P-total, 0.58%; P-phytin, 0.35%). Experiment two consisted of a 2-wk digestibility trial with three treatments: 0 (basal; total P, 0.73%; phytin P, 0.34%), 1,000, and 2,000 PU/kg, assigned to four, three and three replicate tanks respectively. Each tank contained an average of 20 striped bass (mean weight: 400 9). The diet used was similar to the basal in experiment one, which was modified to have low essential trace mineral concentrations, in order to increase the sensitivity of the assay. In experiment one, significant improvements (P≤ 0.05) in growth, feed conversion ratios, and vertebral and scale ash concentrations of fish at the end of the experiment were achieved with either added inorganic P or increasing phytase supplementations. Results from both digestibility trials indicated that P absorption was improved with the addition of at least 500 PUkg. Absorptions of Ca and Fe were significantly increased (P≤ 0.05) and Zn absorption marginally improved (P≤ 0.06) when at least 2,000 PU/kg was supplemented to the diet. Protein digestibility, Mg and Cu absorption were not significantly different in any treatment. Whole carcass P retention was significantly improved with the addition of 1,000 PU/kg, and 2,000 PU/kg, when compared to fish fed the basal diet, 500 PU/kg and positive control treatments. Results from these experiments indicate that phytase supplementation of at least 1,000 PU/kg is adequate to maintain growth rate and health comparable to an inorganic P supplemented diet. In addition, bioavailability and utilization of P is increased with increasing phytase supplementation. Diet supplementation of 2,000 PU/kg increased Ca, Fe, and Zn digestibility by striped bass fed a high phytate diet.  相似文献   
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