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Abstract. Changes in chemical and physical properties and erodibility of a vertisol were studied in relation to land use. The vertisol, which occurs extensively in the semi-arid south-east of Zimbabwe, is derived from basalt and has a self mulching surface layer. Irrigated crops show static yields despite introduction of improved varieties. Four uncultivated sites were selected as controls and compared with five irrigated and four dryland sites. Surface soils were analysed for a range of chemical and physical properties, and laboratory rainfall simulation was used to measure soil erodibility under high intensity rain. The irrigated soils had greater exchangeable sodium and available phosphorus than the uncultivated soils. In contrast, dryland soils showed no such changes apart from a decrease in the amount of small water-stable aggregates. The soils are very erodible under high intensity rain but no significant differences were found between sites. We conclude that, although soil chemical changes have taken place in the irrigated soils, significant soil degradation has not occurred at the sites examined. The static yields probably result from management problems. However, immediate measures should be taken to improve drainage and irrigation management in the irrigated soils to avoid further sodium increases. 相似文献
3.
Mandy L. Wallace Janet A. Grimes Daniel J. Duffy Cameron Kindra Melissa MacIver Samantha Lin Valery F. Scharf Chad W. Schmiedt 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):617
A possible association between the development of nontraumatic, acquired inguinal hernias (NAIH) and perineal hernias (PH) has been postulated in adult dogs. The objective of this study was to evaluate the frequency of concurrent diagnosis of PH in dogs presented with NAIH and determine potential risk factors for concurrent PH and NAIH. Medical records of adult male dogs presented for NAIH to 4 hospitals between 2007 and 2017 were retrospectively reviewed. Twenty-one dogs with NAIH were included, 8 of which had concurrent PH. There were no significant differences between dogs with and without PH; however, among dogs with both conditions, intact dogs (8.1 ± 1.4 years) were younger than neutered dogs (11.7 ± 1.0 years; P = 0.007). Thirty-eight percent of male dogs presenting for NAIH had concurrent PH, indicating that these conditions commonly occur together. Dogs presenting for NAIH should be carefully evaluated for concurrent PH before surgical intervention. 相似文献
4.
Bacillus coagulans GBI-30, 6086 is a commercially available spore-forming non-toxigenic microorganism approved for use in dog foods with high resiliency to stresses associated with commercial manufacturing. The objectives of this research were to examine the effect of B. coagulans on stool quality, nutrient digestibility, and intestinal health markers in healthy adult dogs. Extruded diets containing graded levels of B. coagulans applied either to the base ration before extrusion or to the exterior of the kibble as a topical coating after extrusion were randomly assigned to 10 individually housed adult beagle dogs (7 castrated males and 3 spayed females) of similar age (5.75 ± 0.23 yr) and body weight (12.3 ± 1.5 kg). The study was designed as a 5 × 5 replicated Latin square with 16-d adaptation followed by 5-d total fecal collection for each period. Five dietary treatments were formulated to deliver a dose of 0-, 6-, 7-, 8-, and 9-log10 colony-forming units (CFU) per dog per day for the control (CON), extruded B. coagulans (PEX), and low, moderate, and high B. coagulans coating levels (PCL, PCM, and PCH), respectively. Food-grade TiO2 was added to all diets at a level of 0.4% to serve as an indigestible dietary marker for digestibility calculations. Data were analyzed using a mixed model through SAS (version 9.4, SAS Institute, Inc., Cary, NC) with treatment as a fixed effect and room (i.e., replicate), period, and dog(room) as random effects. Apparent total tract digestibility of organic matter, crude protein, crude fat, and gross energy calculated by the marker method were numerically greatest for dogs fed the 9-log10 dose treatment with increases (P < 0.05) observed in gross energy and organic matter digestibility compared with the negative control. No significant differences were observed in food intake, stool quality, fecal pH, fecal ammonia, fecal short-chain fatty acids, or branched-chain fatty acids for the extruded B. coagulans treatment (PEX) or the coated B. coagulans treatments (PCL, PCM, and PCH) compared with CON. These results suggest that B. coagulans has a favorable impact on nutrient digestibility and no apparent adverse effects when added to extruded diets at a daily intake level of up to 9-log10 CFU in healthy adult dogs. 相似文献
5.
Josephine A. Dornbusch Laura E. Selmic Pin‐Chieh Huang Jonathan P. Samuelson Eric M. McLaughlin Vincent A. Wavreille Jessica A. Ogden Brittany Abrams Alex Kalamaras Eric Green Eric T. Hostnik Lincoln Every Jason A. Fuerst Ryan Jennings Christopher Premanandan Joshua N. Lorbach Sarah C. Linn Aneesh Alex Janet E. Sorrells Lingxiao Yang Stephen A. Boppart 《Veterinary surgery : VS》2021,50(1):111-120
6.
Janet A. Grimes Katherine D. Scott John F. Edwards 《The Canadian veterinary journal. La revue veterinaire canadienne》2016,57(1):76-79
A 2-year-old Dachshund was presented for vomiting and diarrhea. Abdominal ultrasound revealed Dirofilaria immitis in the abdominal aorta and an avascular segment of small intestine. The dog was euthanized. Necropsy revealed D. immitis in the abdominal aorta and widespread necrotizing arteriolitis. This is a unique presentation of aberrant migration of D. immitis. 相似文献
7.
Kendall JR 《Journal of veterinary medical education》2007,34(3):251-256
Distance learning is hardly a recent phenomenon. The recent growth of distance-education courses and programs, particularly those offered online, has been dramatic. Students enrolled in distance-education courses deserve the same quality and type of services that students taking courses on campus receive. The same is true of faculty teaching distance courses. Developing strong support services for both groups is an evolutionary process. This article discusses support services for both students and faculty involved in the rapidly expanding online distance-education landscape. Models for providing support to students and faculty are described, the development of these services is explained, and examples of support services are provided. 相似文献
8.
9.
Kurilich AC Clevidence BA Britz SJ Simon PW Novotny JA 《Journal of agricultural and food chemistry》2005,53(16):6537-6542
The bioavailability of acylated vs nonacylated anthocyanins and the effect of cooking and dose on the comparative bioavailability were investigated in a clinical feeding study using purple carrots as the anthocyanin source. Treatments were purple carrots as follows: 250 g raw (463 micromol of anthocyanins: 400 micromol acylated, 63 micromol nonacylated), 250 g cooked (357 micromol of anthocyanins: 308.5 micromol acylated, 48.5 micromol nonacylated), and 500 g cooked (714 micromol of anthocyanins: 617 micromol acylated, 97 micromol nonacylated). Four of the five carrot anthocyanins were found intact in plasma by 30 min after carrot consumption and peaked between 1.5 and 2.5 h. Acylation of anthocyanins resulted in an 11-14-fold decrease in anthocyanin recovery in urine and an 8-10-fold decrease in anthocyanin recovery in plasma. Cooking increased the recovery of nonacylated anthocyanins but not acylated anthocyanins. Large dose size significantly reduced recovery of both acylated and nonacylated anthocyanins, suggesting saturation of absorption mechanisms. 相似文献
10.
Overestimation of canine albumin concentration with the bromcresol green method in heparinized plasma samples 总被引:5,自引:0,他引:5
Stokol T Tarrant JM Scarlett JM 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(4):170-176
Albumin concentrations are routinely measured in dogs with bromcresol green (BCG)-binding assays on automated chemistry analyzers. Several variables affect this assay, including the length of reaction time, sample type, and lack of specificity of BCG for albumin. We observed that albumin concentrations measured with BCG appeared higher in heparinized plasma samples in sick dogs. The objective of this study was to determine the effect of anticoagulant and assay procedure on BCG albumin concentrations in clinically ill dogs. We hypothesized that albumin concentrations would be overestimated in heparinized plasma compared with serum because of the combination of heparin and fibrinogen. Furthermore, we hypothesized that the overestimation would be influenced by assay parameters. Blood was collected from 32 clinically ill dogs into tubes containing heparin, citrate, or no anticoagulant. Citrate was chosen to assess the effect of fibrinogen in the absence of heparin. Albumin concentration was measured in all 3 sample types from each dog using 2 different BCG procedures on an automated chemistry analyzer. The BCG procedures (standard and modified) differed in the wavelengths used for absorbance readings (standard, 600/700; modified, 570/505) and the time point at which absorbance was measured (standard, 100 seconds; modified, 40 seconds). In addition, the modified method incorporated a sample blank. Globulin fractions, fibrinogen concentration, and indices of lipemia, hemolysis, and icterus were evaluated for their contribution to the overestimation of albumin concentration in heparinized plasma compared with serum samples. Albumin concentrations were significantly higher (P =.05) in heparinized plasma (mean +/- SE, 3.8 +/- 0.1 g/dL) than in serum (3.6 +/- 0.2 g/dL) or citrated plasma (3.2 +/- 0.1 g/dL). Overestimation was evident only with the standard BCG procedure. Multiple linear regression analysis indicated that fibrinogen was largely responsible for the higher albumin concentration in heparinized plasma with the standard method. Based on these results, heparin is not recommended as an anticoagulant for albumin measurement in dogs when using a BCG method unless the assay uses a sample blank and a reaction time of <1 minute. 相似文献