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Conidiobolus coronatus is one of the most commonly identified upper respiratory fungal pathogens in horses. This article includes a review of clinical signs, diagnostics, treatment and outcomes in previously reported cases of equine conidiobolomycosis, as well as six additional cases seen at our hospital. Each of the six horses presented with a complaint of serosanguinous or haemorrhagic nasal discharge and conidiobolomycosis was confirmed by histopathology and fungal culture. Five horses recovered after administration of antifungal drugs alone (n = 4) or in combination with extensive nasal septum resection (n = 1). Surgical treatment alone was ineffective. One horse was euthanised without treatment because of the extent of the disease.  相似文献   
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This field trial was designed to test the effect of treatment with a sustained-release ivermectin bolus on average daily and total weight gain in breeding age Holstein heifers under commercial pasture conditions in southern Quebec. One hundred and twelve heifers from 12 herds were randomly assigned at turnout either to treatment with a commercially-available ivermectin bolus or to remain as untreated controls. Ninety-six heifers, 49 treated animals and 47 controls, completed the trial. Animals were weighed at turnout, midseason, and at the end of the grazing season. Fecal samples were collected at each of these times and nematode eggs counted. Nematode egg excretion was relatively low throughout the pasture season, which was abnormally warm and dry until midsummer. Over the entire pasture season, average daily weight gain was higher in treated than in control animals (difference = 0.08 kg/day, P = 0.010). Total weight gain was also higher in treated animals than in control animals (difference = 12.82 kg, P = 0.013). The results of this study suggest that preventive treatment of breeding age, grazing dairy heifers with a sustained-release ivermectin bolus provides a significant weight gain advantage, in situations with moderate utilization of moderately contaminated pastures.  相似文献   
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Distal border fragments of the navicular bone are increasingly being detected due to the improved capabilities of magnetic resonance imaging (MRI), but their clinical significance remains unclear. The purpose of this retrospective study was to describe the location, size, and frequency of fragments in a cohort of horses presented for MRI of the foot and to compare MRI findings with severity of lameness. Archived MRI studies and medical records were searched from March 2006 to June 2008. Horses were included if a distal border fragment of the navicular bone was visible in MRI scans. Confidence interval comparisons and linear regression analyses were used to test hypotheses that fragments were associated with lameness and lameness severity was positively correlated with fragment volume and biaxial location. A total of 453 horses (874 limbs) were included. Fragments were identified in 60 horses (13.25%) and 90 limbs (10.3%). Fifty percent of the horses had unilateral fragments and 50% had bilateral fragments. Fragments were located at the lateral (62.2%), medial (8.89%), or medial and lateral (28.9%) angles of the distal border of the navicular bone. There was no increased probability of being categorized as lame if a fragment was present. There was no significant difference in fragment volume across lameness severity categorizations. Confidence intervals indicated a slightly increased probability of being classified as lame if both medial and lateral fragments were present. Findings indicated that distal border fragments of the navicular bone in equine MRI studies are unlikely to be related to existing lameness.  相似文献   
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The objective of this study was to determine the effect of feeding Ascophyllum nodosum (ANOD) to lambs at 0 (control), 0.5, 1, or 2% of DMI/d for 2 wk on lamb physiology in response to forced walking and transport during hot weather. Forty-four lambs (26 kg +/- 4.3) were used, and each lamb swallowed 3 gelatin capsules filled with ANOD or their normal 16% CP, pelleted grain ration twice daily, with the amount of ANOD dependent on the treatment. The amount of ANOD did not affect ear canal temperature or cortisol concentrations during 60 min of forced walking. The range between the minimum and maximum ear canal temperature for each lamb during 12 h of transport was narrower in lambs receiving the 2% ANOD than the control group (P = 0.05), and the 2% ANOD group also had lower (P = 0.05) ear canal temperatures than the control group during hot periods of transport. After 4 (P = 0.09) and 8 h (P = 0.05) of transport, the control group tended to have greater cortisol concentrations than the 2% ANOD group. Many differences among treatments were found in plasma protein, albumin, calcium, phosphorus, glucose, blood urea nitrogen, aspartate aminotransferase, magnesium, sodium, potassium, and chloride concentrations posttransport; mainly, the control and 0.5% ANOD groups had greater (P < 0.05) concentrations than the other 2 treatments. Aldosterone concentrations were greater in the control and 0.5% ANOD group than in the 1 and 2% ANOD groups before transport, whereas the concentrations were not different after transport, suggesting pretransport concentrations were lowered by supplementation. The 1 and 2% ANOD groups lost more BW than the control group as a result of transport (P = 0.04). After transport, no differences were observed in the latency for lambs to drink, eat, or lay. There was a suppression of the IgG and IgM antibody responses at 4 and 7 d after administration of ovalbumin, with greater ANOD supplementation rates suppressing antibody response the greatest. Although ANOD decreased ear canal temperature in hot periods of transport, stabilized electrolyte concentrations, and decreased cortisol throughout transport, it also suppressed the antibody response indicating that the effect of ANOD on immune function merits further investigation.  相似文献   
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The effects of elevated temperature, carbon dioxide, and water stress on the isoflavone content of seed from a dwarf soybean line [Glycine max (L.) Merrill] were determined, using controlled environment chambers. Increasing the temperature from 18 degrees C during seed development to 23 degrees C decreased total isoflavone content by about 65%. A further 5 degrees C increase to 28 degrees C decreased the total isoflavone content by about 90%. Combining treatments at elevated temperature with elevated CO(2) (700 ppm) and water stress to determine the possible consequences of global climate change on soybean seed isoflavone content indicated that elevated CO(2) at elevated temperatures could partially reverse the effects of temperature on soybean seed isoflavone content. The addition of drought stress to plants grown at 23 degrees C and elevated CO(2) returned the total isoflavone levels to the control values obtained at 18 degrees C and 400 ppm CO(2). The promotive effects of drought and elevated CO(2) at 23 degrees C on the 6' '-O-malonygenistin and genistin levels were additive. The individual isoflavones often had different responses to the various growth conditions during seed maturation, modifying the proportions of the principal isoflavones. Therefore, subtle changes in certain environmental factors may change the isoflavone content of commercially grown soybean, altering the nutritional values of soy products.  相似文献   
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The cation exchange capacity (CEC) of a soil depends on the type and amount of both mineral and organic surfaces. Previous studies that have sought to determine the relative contribution of organic matter to total soil CEC have not addressed differences in soil organic matter (SOM) composition that could lead to differences in CEC. The objectives of this study were (1) to compare the CEC of two distinct SOM pools, the “light fraction (LF)” composed of particulate plant, animal, and microbial debris, and the “heavy fraction (HF)” composed of mineral-bound organic matter; and (2) to examine the effects of differences in aboveground vegetation on CEC. Soil samples were collected from four paired grassland/conifer sites within a single forested area and density fractionated. LF CEC was higher in conifer soils than in grassland soils, but there was no evidence of an effect of vegetation on CEC for the HF or bulk soil. LF CEC (but not HF CEC) correlated well with the C concentration in the fraction. The mean CEC of both fractions (per kg fraction) exceeded that of the bulk soil; thus, when the LF and HF CEC were combined mathematically by weighting values for each fraction in proportion to dry mass, the resulting value was nearly twice the measured CEC of bulk soil. On a whole soil basis, the HF contributed on average 97% of the CEC of the whole soil, although this conclusion must be tempered given the inflation of CEC values by the density fractionation procedure.  相似文献   
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