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941.
942.
The effects of resistant starch (RS) intake on nutrient digestibility, microbial fermentation products, faecal IgA, faecal pH, and histological features of the intestinal mucosa of old dogs were evaluated. The same formulation was extruded in two different conditions: one to obtain elevated starch cooking degree with low RS content (0.21%) and the other lower starch cooking with high RS content (1.46%). Eight geriatric Beagles (11.5 ± 0.38 years old) were fed each diet for 61 days in a crossover design. Food intake, nutrient digestibility, fermentation products, faecal pH, and faecal IgA were examined via variance analysis. Histological results of intestinal biopsies were assessed via Wilcoxon test for paired data. The morphometric characteristics of large intestine crypts were evaluated via paired t tests (p < .05). Protein, fat, and energy digestibilities were higher for the low‐RS diet (p < .05). Dogs receiving the high‐RS diet had lower faecal pH and higher values for propionate, butyrate, total volatile fatty acids, and lactate (p < .05). No differences between diets were found in the histological parameters of the gut mucosa, and only a tendency for deeper crypts in the descending colon was observed for dogs fed the high‐RS diet (p = .083). The intake of a corn‐based kibble diet manufactured with coarse ground raw material and low starch gelatinization to obtain 1.4% of RS affected microbial fermentation products and faecal pH and tended to increase crypt depth in the descending colon of old dogs.  相似文献   
943.
Benzimidazole anthelmintic drugs are widely used in veterinary practice. Albendazole sulphoxide (ABZSO) is a benzimidazole drug with two enantiomers, as a consequence of a chiral centre in the sulphoxide group. The kinetics of these enantiomers were studied in male and female sheep. Plasma samples were obtained from the animals between 0.5 and 72 h after oral administration of 7.5 mg/kg of a racemic formulation of ABZSO (total-ABZSO). After a liquid–liquid extraction, the samples were analysed by HPLC to determine the concentrations of total-ABZSO and of the sulphone metabolite (ABZSO2). During the chromatographic analysis, the ABZSO peak was collected and reanalysed by an HPLC technique using a Chiral AGP column to quantify the enantiomeric proportion therein. After kinetic analysis, the AUCs obtained for the (+)-ABZSO were 5.8 and 4.0 times higher than those for the (–)-ABZSO in male and female animals, respectively. The mean residence times were 23.4 and 16.1 h for (+)-ABZSO and 22.2 and 17.4 h for (–)-ABZSO for male and female animals, respectively. The only significant difference between the sexes (p<0.05) was in the T max of the (–)-ABZSO. Comparing both enantiomers within each sex, significant differences were found in all the kinetic parameters. Finally, no kinetic differences were found between sex for total-ABZSO or ABZSO2.  相似文献   
944.
A case of unilateral spastic paresis in a Poll Hereford heifer is described. The heifer could not actively flex the right stifle or hock and the toe just contacted the ground. There was cranial distortion and collapse of the distal tibial epiphysis and remodelling of the articular surfaces within the stifle and hock. There was moderately severe muscle atrophy, but a primary peripheral or central neuropathological lesion could not be found.  相似文献   
945.
A two-year experiment was conducted at the Beltsville Agricultural Research Center (BARC), MD, and Virginia Polytechnic Institute and State University Kentland Agricultural Research Farm (KARF), VA, to evaluate potato (Solanum tuberosum L.) production of 32- to 57-mm-size-range tubers (referred to hereafter as creamers) in a conservation-tillage, cover-cropping strategy. The experiments used a split-plot design in which the main-plots were cover crop treatments and the sub-plots were different potato selections. Main plot treatments included rye (Secale cereale L.), crimson clover (Trifolium incarnatum L.), Austrian winter pea (Pisum sativum L.), rape (Brassica napus L.), oat (Avena sativa L.), rye/crimson clover mixture, rape/crimson clover mixture, bare soil/raised beds, and bare soil/flat beds (control). Potato selections tested were B1145-2, B1491-5, and B1492-12 in 2000 and B1145-2, B1102-3, and B0811-4 in 2001. Yields in the conservation-tillage treatments were equal to or better than those in the bare soil/flat bed control with few exceptions. Large-sized tubers (<57 mm) in almost all cases remained below 6% of total marketable yield even when the tubers were harvested late. Delayed harvest did not reduce creamer-sized yields nor did it increase yield of large-sized tubers. Economic analysis shows that net returns from some conservation-tillage treatments are equal to or higher than the conventional-tillage strategy and confirms the viability of the conservation-tillage, cover-cropping strategy. Furthermore, the conservation-tillage strategy in many cases allows timely planting using machinery in the wet soils of Maryland and Virginia during the narrow window of spring potato planting time, whereas the conventional tillage strategy does not offer this advantage.  相似文献   
946.
The kinetics of albendazole metabolites and albendazole sulphoxide enantiomers were studied in 2- and 14-month-old female and male goats, after a single oral dose administration (10 mg/kg) of an albendazole formulation. Blood samples from the jugular vein were collected at 0.5, 1, 2, 4, 6, 8, 10, 12, 16, 20, 24, 30, 36, 42, 48 and 54 h post-treatment and analyzed using a high performance liquid chromatography method. In all groups the area under the plasma concentration-time curve (AUC) and peak concentration (Cmax) values of (+)-ABZSO were significantly higher than those of (−)-ABZSO. The AUC and Cmax values obtained for (+)-ABZSO and (−)-ABZSO in adult animals were higher compared to the results in young animals, showing significant differences except for (+)-ABZSO in female animals. In young animals, independently of gender, the Cmax appeared earlier compared to adult animals. The mean residence time (MRT) values were shorter in young animals compared to adult animals for all compounds analyzed. No sex-related differences were found for any of the parameters calculated except for the (+)-ABZSO from adult animals.  相似文献   
947.
The major nematode pests of cultivated plants in Greece include root-knot nematodes Meloidogyne spp. (in almost all plants except citrus), cyst-forming nematodes Globodera rostochiensis, G. pallida (in potato), Heterodera avenae (in cereals), Ditylenchus dipsaci (in vegetables and ornamental plants) and Tylenchulus semipenetrans (in citrus). Based on observations made on samples examined at Benaki Phytopathological Institute, it was confirmed that serious infestation of new kiwi orchards with Meloidogyne spp. originated from seedlings infested at the nursery. Also the wide distribution of the nematode Tylenchulus semipenetrans in citrus orchards was mainly attributed to infested seedlings. The above observations led us, in 1985, to the decision to study the nematological fauna of nurseries in Greece.  相似文献   
948.
Liming of acidic agricultural soils has been proposed as a strategy to mitigate nitrous oxide (N2O) emissions, as increased soil pH reduces the N2O/N2 product ratio of denitrification. The capacity of different calcareous (calcite and dolomite) and siliceous minerals to increase soil pH and reduce N2O emissions was assessed in a 2-year grassland field experiment. An associated pot experiment was conducted using homogenized field soils for controlling spatial soil variability. Nitrous oxide emissions were highly episodic with emission peaks in response to freezing–thawing and application of NPK fertilizer. Liming with dolomite caused a pH increase from 5.1 to 6.2 and reduced N2O emissions by 30% and 60% after application of NPK fertilizer and freezing–thawing events, respectively. Over the course of the 2-year field trial, N2O emissions were significantly lower in dolomite-limed than non-limed soil (p < .05), although this effect was variable over time. Unexpectedly, no significant reduction of N2O emission was found in the calcite treatment, despite the largest pH increase in all tested minerals. We tentatively attribute this to increased N2O production by overall increase in nitrogen turnover rates (both nitrification and denitrification) following rapid pH increase in the first year after liming. Siliceous materials showed little pH effect and had no significant effect on N2O emissions probably because of their lower buffering capacity and lower cation content. In the pot experiment using soils taken from the field plots 3 years after liming and exposing them to natural freezing–thawing, both calcite (p < .01) and dolomite (p < .05) significantly reduced cumulative N2O emission by 50% and 30%, respectively, relative to the non-limed control. These results demonstrate that the overall effect of liming is to reduce N2O emission, although high lime doses may lead to a transiently enhanced emission.  相似文献   
949.
Clinically healthy domestic animals can harbour Escherichia coli O157 and other verocytotoxigenic E. coli (VTEC) strains in their faeces. Milk filters can be used to microbiologically monitor direct milk secretion and environmental contamination for these pathogens. The aim of this study was to establish baseline data on the prevalence and characteristics of VTEC organisms in lactating animals (bovine, ovine and caprine) supplying milk to the farmhouse cheese sector, with particular emphasis on serogroups O157, O111 and O26. Fifty-six bovine, 13 caprine and 5 ovine herds/flocks, the majority of which supplying milk for farmhouse cheese production, were surveyed from May 2004 to July 2005. Milk filters were analysed by immunomagnetic separation followed by PCR, on a serogroup-specific basis for E. coli O157, O26 and O111. Positive isolates were examined using a multiplex PCR protocol, for their potential to produce verocytotoxins (vt1/vt2), the haemolysin-encoding gene (hlyA) and the gene encoding attaching and effacement (eae). Five verocytotoxigenic and 22 non-virulent E. coli O157 isolates were detected. Seventeen E. coli O26 isolates were also detected, four of which were verocytotoxigenic, seven isolates contained the eae gene only and six isolates were devoid of any of the virulence factors. The VTEC O157 and O26 isolates contained the hlyA and eae genes along with the verocytotoxin genes. No E. coli O111 isolates were detected. Some of the herds were positive on more than one occasion and multiple E. coli serogroups were isolated from the same milk filter sample. Although all food products tested were VTEC negative, routine surveillance for such pathogens in raw milk/raw milk products is of public health importance. Herd-level surveillance along with subsequent risk management action may be a cost-effective component of risk reduction strategies for food production, drinking water supplies and the protection of public health.  相似文献   
950.
Brush cytology was used as a diagnostic aid in 85 cats affected with chronic intranasal disease. Fifty-three of these cases, sampled over a five-year period, were included in this study, while the other cases were excluded due to poor cellularity of the cytological samples (nine cases) or a lack of histological or follow-up data (23 cases). Thirty-six brush samples were classified by cytology as inflammatory. Subsequent histological examination revealed a false negative diagnosis of neoplasia in six cats, two of which had malignant tumours (one adenocarcinoma and one lymphoma), the remaining four having benign tumours (two adenomas and two osteochondromas). Seventeen samples were classified by brush cytology as neoplastic. This was confirmed in 16 of these cases by histology or follow-up (nine epithelial malignant tumours, six lymphomas and one osteosarcoma). In the remaining case, a false positive diagnosis of lymphoma was made. The procedure had an overall 86.8 per cent (46/53) agreement between the diagnosis of inflammatory conditions versus neoplasia, with a sensitivity of 72.7 per cent, a specificity of 96.8 per cent, a predictive value of a positive test of 94.1 per cent and a predictive value of a negative test of 83.3 per cent.  相似文献   
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