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21.
Summary

Histological examination of 753 Beagle dogs showed renal foci of calcification in 27.9% of males and 21.5% of females. In contrast, stomach calcification was observed in 6.2% of males and 5.2% of females examined.

It is suggested that the focal calcification seen in both organs was possibly of dietary origin and may have been related to the phosphate content.  相似文献   
22.
Desert soils are infertile, and the ability to improve them by P-fertilization is limited by the solubility of phosphate. We aimed to understand the function of phosphate solubilizing bacteria and the mechanisms behind phosphate solubilization in desert soils. Vegetated and barren desert soils, mine spoil and a fertile temperate grassland loam were sampled. Bacteria and fungi were isolated and identified, and their phosphate-solubilizing abilities were measured in vitro. The release of plant available PO4, SO4, NO3 and NH4 from desert soils did not compare with that of a grassland soil. Desert soils had substantially lower solubilization than grassland, 162 and 99–121 µg PO4-P g?1 dry soil, respectively. Phosphate-solubilizing bacteria and fungi were inhabiting the soils. Si addition increased phosphate solubilization of fungi by 50%. The isolated microbes were shown, using 31P nuclear magnetic resonance (NMR) analysis, to rapidly take-up both intracellular and extracellular phosphate during the phosphate solubilizing process. Desert soil had potentially active microbial populations that are capable to solubilize inorganic phosphorus; S and Si as the limiting factors. Acidification as the main mechanism to solubilize mineral phosphate was not as evident in our desert soils as in former studies dealing more fertile soils.  相似文献   
23.
The objectives of this study were to investigate the effects of flaxseeds and/or fenugreek seeds as a source of phytoestrogens in laying feed on productive performance, egg quality, yolk fatty acids, plasma profile and antioxidative status in aged laying hens. A total of 120 Bovans Brown hens at 65 weeks of age were housed individually in laying cages in an open‐sided building under a 16‐hr light: 8‐hr dark lighting schedule. Hens were randomly divided into four experimental treatments (n = 30 each): (a) control (basal diet without any supplementation); (b) 1 g/kg of flaxseeds; (c) 1 g/kg of fenugreek seeds; and (d) combination of 1 g/kg flaxseeds and 1 g/kg fenugreek seeds from 65 to 71 weeks of age. Hen‐day egg production and egg mass were significantly increased by dietary supplementation of flaxseeds and/or fenugreek seeds, while feed intake was not affected; thus, feed conversion ratio was improved (p < 0.05). Weights of egg, albumen, yolk and shell were increased by the dietary treatments. Shell thickness and yolk colour were improved by supplementation of flaxseeds and/or fenugreek seeds. Yolk crude protein was not significantly affected by treatments; however, crude fat and calcium contents in yolk were increased and egg yolk cholesterol content was decreased. Interestingly, dietary supplementation of flaxseeds, fenugreek seeds and their combination had a significant positive effect on plasma luteinizing hormone, follicle‐stimulating hormone, oestradiol‐17β and triglycerides. Inclusion of flaxseeds and/or fenugreek seeds in the diets enhanced the serum glutathione peroxidase and superoxide dismutase activities and reduced the malondialdehyde and total cholesterol concentrations in plasma. Dietary supplementation of flaxseeds and/or fenugreek seeds increased α‐linolenic and linoleic acids in egg yolk. It could be concluded that inclusion of mixed sources of phytoestrogens in diets improved laying performance, egg quality, the antioxidative status, hormonal profile and steroidogenesis in aged laying hens.  相似文献   
24.
Tilmicosin was injected subcutaneously to lactating ewes once at a dose of 10 mg kg-1 b.wt. to determine its plasma, milk, urine and ruminal juice concentrations. Tilmicosin could be detected in all those fluids 30 minutes after injection. Milk and urine concentrations were higher than those of plasma and ruminal juice. The drug was detectable in milk, urine and plasma for 9, 4 and 3 days after injection, respectively. No amount of tilmicosin could be detected in ruminal juice 12 hours following administration. The mean peak concentration of tilmicosin in plasma and milk (Cmax) were 1.29 and 9.5 micrograms ml-1 and were obtained at (Tmax) 5.235 and 15.093 hours, respectively. The drug was slowly eliminated from plasma and milk as indicated by its long half-life (t1/2el) of 15.4 and 26.2 hours, respectively. The mean binding of tilmicosin to plasma and milk proteins in vitro was 16.8% and 26.8%, respectively. The drug was not bound to ruminal juice at any extent. The rate of tilmicosin renal clearance revealed that it was correspondingly increased with higher blood concentrations. While creatinine clearance showed no significant change after tilmicosin administration. The ratio (fractional clearance) between tilmicosin renal clearance to creatinine clearance was less than one indicating that the glomerular filtration is the main pathway of elimination through kidneys. The rate of ruminal gas fermentation in ewes was inhibited after subcutaneous injection of tilmicosin at a dose of 10 mg kg-1 b.wt. The tested samples taken at different time intervals from the rumen of ewes showed a subsequent reduction in the rate of fermentation as compared to control samples. The reduction was correspondingly increased with the increase of tilmicosin concentration in ruminal juice and returned to normal thereafter.  相似文献   
25.
Despite the interest of meagre (Argyrosomus regius) as a fast‐growing candidate for Mediterranean aquaculture diversification, there is a lack of information on nutrition along larval development. Importance of highly unsaturated fatty acids (HUFA) and the antioxidant vitamins E and vitamin C has not been investigated yet in this species. Six diets with two levels of HUFA (0.4% and 3% dw), two of vitamin E (1500 and 3000 mg kg?1) and two of vitamin C (1800 and 3600 mg kg?1) were fed to 15 dah meagre larvae. Larval growth in total length and dry body weight was significantly lowest in larvae fed diet 0.4/150/180 and showed few lipid droplets in enterocytes and hepatocytes and lower HUFA contents than the initial larvae. Increase in dietary HUFA up to 3%, significantly improved larval growth and lipid absorption and deposition. Besides, among fish fed 3% HUFA, increase in vitamin E and vitamin C significantly improved body weight, as well as total lipid, 22:6n‐3 and n‐3 fatty acids contents in the larvae. Thus, the results showed that 0.4% dietary HUFA is not enough to cover the essential fatty acid requirements of larval meagre and a high HUFA requirement in weaning diets is foreseen for this species. Besides, the results also pointed out the importance of dietary vitamin E and C to protect these essential fatty acids from oxidation, increase their contents in the larvae and promote growth, suggesting high vitamin E and C requirements in meagre larvae (higher than 1500 and 1800 mg kg?1 for vitamin E and vitamin C respectively).  相似文献   
26.
27.
Ethanolic extracts of 58 Malaysian plants belonging to 24 different families were screened for antifungal activity against seven plant pathogens using the filter paper disc diffusion technique. Two varieties of Piper betle, showed strong activity against all the pathogens tested (Colletotrichum capsici, Fusarium pallidoroseum, Botryodiplodia theobromae, Alternaria alternata, Penicillium citrinum, Phomopsis caricae-papayae and Aspergillus niger), with inhibition diameters significantly (P<0·01) bigger than 2·5 mg ml−1 prochloraz or 10 mg ml−1 clotrimazole. The minimum inhibitory concentrations of the ethanolic extracts of P. betle against these plant pathogens ranged between 0·01 mg ml−1 and 1 mg ml−1. Thirty-four other plants (Kucing gala, Limau batik, Bertholletia excelsa, Bixa orellana, Caesalpinia pulcherrima, Cerbera odollam (fruits and leaves), Colocasia gigantea, Curcuma domestica, Curcuma manga, Derris eliptica, Elephantopus scaber, Eleusine indica, Eugenia polyantha, Euphorbia hirta, Euphorbia tirucalli, Gardenia florida, Hedyotis auricularia, Hibiscus rosa-sinensis, Juniperus chinensis (three varieties), Lawsonia inermis, Lecythis ollaria, Mentha arvensis, Mimusops elengi, Ocimum sanctum, Phyllanthus niruri, Piper nigrum, Piperomia pellucida, Pedilanthus tithymaloides, Polygonum minus, Spondias dulcis, Solanum nigrum, Tinospora tuberculata) showed selective antifungal activity, while 21 species were inactive.  相似文献   
28.
29.
This study was undertaken to assess the effects of feeding European seabass (Dicentrarchus labrax) canola oil-added diets on growth, health status and liver and intestine histomorphology. Seabass (56.18 ± 0.16 g initial body weight) were fed one of three fish meal-based diets with ~48 % crude protein and ~16.0 % lipid, combining fish oil (FO) and canola oil (CO) for 12 weeks. The diets contained: zero (control, CTRL), 45 (CO50) or 63 (CO70) g CO kg?1 assigned in triplicates to three dietary groups. The results indicated that neither dietary oil type (FO or CO) nor CO level adversely affected (P > 0.05) the growth, feed utilization or major blood constituents’ composition as an indicator of the overall health status of fish. Despite the CO diets influence on head kidney macrophage activity being unappreciable (P > 0.05), there was a reducing trend with an increase in CO level incorporation. The CO70 diet induced a minor fat infiltration in hepatocytes and leucocytes infiltration, hyperplasia of the basal nuclei and supranuclear vacuolization of the enterocytes of the distal intestine. The present observations suggest that it is possible to incorporate up to 63 g CO Kg?1 in the feed for European seabass juveniles without major negative effects on growth, health status or liver and intestinal histomorphology.  相似文献   
30.
This study investigated the effects of fish meal replacement by Spirulina platensis meal on growth, survival, body biochemical composition, and reproductive performance of Trichopodus trichopterus until the first spawning for 16 weeks. The fish fed dietary algal meal at levels of 2.5, 5, 10, and 20 % against those received fish meal only as control. The results showed that indicators such as belly diameter, feed intake, feed conversion ratio (FCR), and viscerosomatic index were significantly different between treatments with 5 and 10 % algal replacements (P < 0.05). The growth factors including final weight, weight gain, total length, fork length, and body height of fish did not show significant differences (P > 0.05) between the treatments. Feed intake increased up to 10 % replacement level and then decreased, though the best FCR values (0.77–0.79) were obtained with 2.5 and 5 % substitutions. The body lipid content showed a statistically marked decrease (P < 0.05) as a result of the algal replacements, but the amounts of protein and moisture were not significantly (P > 0.05) different between treatments. All fish fed S. platensis meal had greater gonadosomatic indices (19.4–21.85 %) than that of the control in spite of insignificant differences (P > 0.05) in their ovary weights (2.07–2.21 g). Absolute fecundity ranged between 7300 and 12,700 eggs/female with the highest amount in fish fed with replaced S. platensis levels of 2.5–10 %. The second-order polynomial regression analysis between absolute fecundity and substitution levels of algal meal was y = ?0.5319x 2 + 106.87x + 7812.9 (R 2 = 0.9642), and the optimal substitution level was determined to be 8.13 % for maximum absolute fecundity. Hatching percentages in the control and 20 % replacement were much lower (P < 0.05) than those in the other treatments (78–86 %). Given the relative enhancement of growth parameters and significant improvement in reproductive performance of broodstock three-spot gourami, 8.1–9.6 % S. platensis meal instead of fish meal is recommended in the diets.  相似文献   
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