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91.
Soybean [Glycine max (L.) Merril] is the leading food crop worldwide, and selection of soybean genotypes for different levels of soil acidity may raise crop yield without the need to increase in planted area. An experiment in greenhouse conditions was conducted to determine the effects of two lime rates on soil chemical properties, grain yield (GY), yield components, nutritional status and physiological components of 15 soybean genotypes adapted to tropical and subtropical conditions. Genotypes BMX Apolo RR, BMX Potência RR, BRS 295RR, BRS 359RR, FPS Solar IPRO and TMG 716 IRR were the least responsive to soil acidity reduction, and BMX Turbo RR and BRS 360RR were the most responsive. Number of pods per pot, shoot dry weight yield, GY, photosynthesis, stomatal conductance, transpiration and chlorophyll increased significantly with increase in lime rate. Cultivar FPS Solar IPRO showed the highest foliar P, K, Ca and Mg concentrations in soybean, which was not observed in the grain, indicating the presence of genetic factors and the dilution effect on nutrient uptake.  相似文献   
92.
Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 µg/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and β-carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value.  相似文献   
93.
We examined the effects of cyclic fasting in red porgy (Pagrus pagrus) fed different dietary carnitine levels. Juvenile fish (23.58 ± 3.49 g) were divided into eight groups – four groups were fed every day to apparent satiation, while the other four were fasted for 7 days every 2 weeks. In each feeding regime, two replicates were fed an l ‐carnitine non‐supplemented diet (46 mg kg?1) and the other two groups were fed an l ‐carnitine supplemented diet (630 mg kg?1). Fish fed 630 mg l ‐carnitine accumulated two times more l ‐carnitine in muscle than fish fed 46 mg l ‐carnitine. Cyclic fasting reduced the growth performance and lipid content in the liver. Carnitine supplementation did not affect performance and body composition, but decreased the n‐6 PUFA content. Moreover, the combined effects of fasting and carnitine supplementation were observed on reducing the n‐3 fatty acid content. Areas of steatosis were found in the livers of red porgy, but the results revealed that supplementation of l ‐carnitine in cyclic fasted fish contributed towards a lower degree of vacuolization than in fish fed to apparent satiation. Regardless of the feeding regime applied, the spleen of fish fed the l ‐carnitine‐supplemented diet was haemorrhagic and hyper activation of melanomacrophage cells was observed.  相似文献   
94.
An excess of phosphorus (P) is the most common cause of eutrophication of freshwater bodies. Thus, it is imperative to reduce the concentration of P to prevent harmful algal blooms. Moreover, recovery of P has been gaining importance because its natural source will be exhausted in the near future. Therefore, the present work investigated the removal and recovery of phosphate from water using a newly developed hybrid nanocomposite containing aluminium nanoparticles (HPN). The HPN-Pr removes 0.80?±?0.01?mg?P/g in a pH interval between 2.0 and 6.5. The adsorption mechanism was described by a Freundlich adsorption model. The material presented good selectivity for phosphate and can be regenerated using an HCl dilute solution. The factors that contribute most to the attractiveness of HPN-Pr as a phosphate sorbent are its moderate removal capacity, feasible production at industrial scale, reuse after regeneration and recovery of phosphate.  相似文献   
95.
SUMMARY The epidemiological, clinical and pathological features of a disease syndrome in adult cattle grazing woolly-pod vetch (Vicia villosa ssp dasycarpa) or popany vetch (V benghalensis) are reported. Outbreaks of toxlcosis occurred between midwinter and midsummer in 3 dairy and 6 beef herds on the north coast of New South Wales, between 1982 and 1992. Friesian, Angus, Murray Grey, Guernsey and Hereford breeds were affected. Mean morbidity and case fatality rates in affected herds were 7% (65 of 889) and 69%, respectively. Signs of pruritic dermatitis, illthrift and death were associated with an eosinophilic granulomatous inflammation of many organs, particularly involving the renal cortex, dermis, myocardium, adrenal glands, lymph nodes and hepatic portal triads.  相似文献   
96.
Objective To determine the effect of treating naturally acquired gastrointestinal nematode and paramphistome infections on milk production in dairy cattle.
Design A field trial.
Animals One thousand two hundred and thirty nine dairy cows.
Procedure Cows were either not treated or treated with 4.5 mg/kg oxfendazole, 16.6 mg/kg oxyclozanide or 4.5 mg/kg oxfendazole and 16.6 mg/kg oxyclozanide in March, May and August.
Results A significant increase in milk production, averaging 0.4 L (SE 0.2) per day, was seen when dairy cows infected with gastrointestinal nematodes and paramphistomes were treated with oxfendazole or oxfendazole and oxyclozanide in March, May and August. Cows treated with oxyclozanide alone at these times produced no more milk than untreated cows.
Faecal egg counts confirmed that oxyclozanide treatment reduced paramphistome populations and oxfendazole treatment reduced nematode populations in cows over the 7-month monitoring period.
Conclusion When dairy cows infested with gastrointestinal nematodes and paramphistomes were treated with oxfendazole alone or oxfendazole and oxyclozanide in March, May and August milk production increased.  相似文献   
97.
Histological, histometric and histochemical studies of the mandibular salivary glands of suckling, prepuberal and puberal zebu were carried out using 14 male animals. The developmental growth of this gland is characterized and correlated with histochemical development. These findings were correlated with other similar studies of Bovidae.  相似文献   
98.
A 3-year-old female pug (8 kg bodyweight) was referred by a local veterinarian for evaluation of vaginal bleeding. Historically, the owner indicated chronic haematic vaginal discharge initiated approximately 3 months ago, overall good appetite and slight general dullness. Two months prior to the visit, the bitch had been spayed by the local veterinarian, but vaginal bleeding persisted after surgery. Following a general examination and complete blood analysis, a genital tract examination was performed and, through vaginal endoscopy, a red, smooth, and apparently broad-based vaginal mass was found. An episiotomy was performed and on surgical exploration, the bleeding site was determined to be on the surface of a mass composed of two congested, adjacent cylindrical structures, symmetric to the vaginal sagittal midline, broad-based and quite regular on the surface. The mass appeared to be well delimited from the surrounding tissue by a thin capsula, and each cylindrical structure had a tributary vessel. Ectopic and dysplastic corpora cavernosa of the clitoris characterized by angiomatous proliferation, cavernous haemangioma and vascular hamartoma were considered in the differential diagnosis. The presence of small intralesional nerves identified by S100 immunostaining was used as a diagnostic clue to classify this unusual vaginal angiomatous neoformation as vascular hamartoma.  相似文献   
99.
The aim of this study was to evaluate the accuracy of ultrasonographic measurement of the deep portion of diencephalo‐telencephalic vesicle (DPTV) in the prediction of delivery date in different size bitches. The effects of litter size and foetal sex ratio on the accuracy were also investigated. For this purpose, the growth curve of DPTV was derived in large size dogs (26–40 kg) and the results of the accuracy of the prediction were compared with those obtained in small (≤10 kg) and medium (11–25 kg) size dogs by the application of the equations derived from the growth curve previously described. Ultrasonographic examinations were performed once a week during the second half of pregnancy in seven large size bitches (26–40 kg body weight). A linear regression model was adopted to analyse the relationship between the DPTV mean values and the days remaining to parturition. The results of regression analysis indicated that DPTV measurement in large size dogs is significantly and linearly related to the gestational age. Ultrasonographic measurements of DPTV were also performed during pregnancy in different size bitches with unknown breeding dates. Although the results indicated a similar accuracy of the prediction of the date of parturition in the different sizes of bitches, a higher accuracy was obtained in normal and large litter size compared with small litters. Foetal sex ratio did not affect the accuracy. In conclusion, this study demonstrated that the accuracy of the prediction of parturition day obtained by ultrasonographic evaluation of DPTV growth is reliable when specific formulae for different size dogs are applied. It should be noted that although foetal sex ratio does not affect the accuracy, the prediction could be less accurate when a small litter is present.  相似文献   
100.
The aim of this experiment was to evaluate the effects of adding ascorbic acid 2‐glucoside (AA2G), a water‐soluble antioxidant and stable derivative of ascorbate, to the semen extender and compare it to the addition of vitamin C (Vit. C) and the fat‐soluble antioxidant α‐tocopherol (α‐Toh), both individually and in combination, on the seminal variables of equine sperm submitted to cooling for 72 h. We used two ejaculates from 10 stallions and evaluated them for motility, membrane integrity, chromatin fragmentation, mitochondrial activity and lipid peroxidation. In the analysis of lipid peroxidation, the control group showed 2506.2 ± 796.4 ng malondialdehyde/108 sperm, which was higher (P < 0.05) than the groups treated with antioxidants. The average value of motility in the AA2G group was 68.4 ± 18.1%, which was higher (P < 0.05) than that observed in the control group (62.1 ± 16.2%). The variables membrane integrity, chromatin fragmentation and mitochondrial activity did not show significant difference (P > 0.05) between treatments. It was concluded that the antioxidants protected sperm cells from lipid peroxidation and that AA2G was effective during the cooling process of equine semen at 5°C for72 h, providing increased levels of total motility.  相似文献   
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