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771.
Long‐chain alcohols (LCOH) were evaluated as markers to estimate diet composition of ruminant species fed with two distinct diets composed of herbage and “heather” (Ericaceae species). Diet composition was estimated using LCOH, combined or not with n‐alkanes and/or long‐chain fatty acids (LCFA), by least‐squares procedures, using faecal concentrations corrected or not for their incomplete recovery. The effect of grouping plant species with similar marker profiles and the impact of feeding selectivity (FS) within the dietary group on the accuracy of diet composition estimates were also evaluated. Results showed the usefulness of LCOH as diet composition markers. The LCOH were incompletely recovered in the faeces of all animal species and tended to increase with carbon‐chain length in a curvilinear manner in cattle and sheep, whereas in goats this association was better described by a linear function. Accuracy of estimates was higher when LCOH and n‐alkane markers were combined. For all marker types, results indicated that a correction of marker faecal concentrations to incomplete faecal recovery is needed to obtain accurate diet composition estimates. Grouping plant species with similar marker profiles improved the accuracy of estimates, whereas combination of marker types minimized the FS effect within the dietary group.  相似文献   
772.
The tomato (Solanum lycopersicum L.) cultivar Micro‐Tom (MT) is widely used in physiological studies, but the effects of nitrate ( ) and ammonium ( ) ratios ( : ratios) and, in particular, the effects of the accompanying ions in sources are unknown. To determine whether the accompanying ions in sources influence toxicity, the effects of : ratios on the physiology, electrolyte leakage index, nutrition, and dry weight were studied using hydroponics. The sources were ammonium chloride (NH4Cl) or ammonium sulfate [(NH4)2SO4], and five : ratios were used: 100 : 0, 75 : 25, 50 : 50, 25 : 75, and 0 : 100. The source was calcium nitrate [Ca(NO3)2], and the nitrogen (N) concentration was 15 mmol L?1. The results indicate that NH4Cl or (NH4)2SO4 can be used in studies on toxicity because the accompanying ions did not influence the tomato plants. In addition, : ratios of 100 : 0 and 75 : 25 resulted in the highest dry weight of tomato plants, whereas ratios of 25 : 75 or 0 : 100 were toxic.  相似文献   
773.
The aim of this study was to evaluate the genotoxic and mutagenic potential of contaminated soil diluted in acidic solutions and not acidic, in the offspring of rats exposed during pregnancy and neonatal periods. To this end, a comet assay and micronucleus test were performed. Soil samples were solubilized in the following three solvents: distilled water (control group), acid solvent at pH 5.2, and acid solvent at pH 3.6. Soil and solvent were mixed in a rate of 1:2 in g/mL, and hydrofluoric acid was used in the acid solvents. In the comet assay, the tail length, percentage of DNA within the tail and tail moment was analyzed in the whole blood of the pups that were studied. The number of micronuclei found in the bone marrow cells was counted in the micronucleus test. In all parameters evaluated in the comet assay, the group exposed to the lowest pH value when associated with contaminated soil (p < 0.05) had the most damage. However, the micronucleus test showed differences between all exposed groups and the control group (p < 0.05). These results reaffirm the health risks related to the exposure to soil contaminants.  相似文献   
774.
The present study was conducted to investigate the growth response of Ceriops tagal Perr.) C.B. Robinson a mangrove species belonging to the family Rhizophoraceae. Three dominant native arbuscular mycorrhizal (AM) fungal species viz., Rhizophagus clarus, R. intraradices, and Acaulospora laevis were selected. The results revealed that the Mycorrhizal Plant Responsiveness (MGR) was greater in AM inoculated plants compared to control plants. Among AM fungal treatments, plants inoculated with R. clarus recorded significant increase in growth responses compared to remaining AM treatments. The study suggests that R. clarus was the most efficient AM species exhibiting greater influence on growth and biomass. Differences in growth parameters between AM inoculated treatments and control are reasonably linked to colonization levels. The result of the present study indicates that potential native AM fungal species can be use in mangrove reforestation programs as bio-inoculum.  相似文献   
775.
The study evaluated the effect of gender status on carcass and meat quality of feedlot Angus × Nellore cattle. A total of 176 cattle, 20 months old, were confined for 190‐days and assigned to four treatments: bulls, immunocastrated, steers, and heifers. Bulls had greater rib eye area and HCW (p = 0.0001). Heifers had increased fat thickness (p = 0.0001). Steers and heifers had higher marbling scores (p = 0.0001). There was interaction between gender and aging time for Warner‐Bratzler Shear Force (p = 0.0002), L* (p = 0.0118), and b* (p = 0.0113) values of beef. The sensory panel results showed that beef from bulls had the lowest consumer overall acceptance (p = 0.0278). Especially, regardless tenderness, steers and immunocastrated beef were considered tender, independent of aging time. Beef produced by heifers, steers, and immunocastrated is considered to be of higher quality than bulls. Thus, it is may be an interesting alternative to produce high‐quality beef than bulls, to attend the consumer demand for high‐quality products. Additionally, the low fatty acids n6 levels and low n6:n3 ratio, high levels of CLA, MUFAs, and oleic acid suggests that the heifer meat is favorable for human health.  相似文献   
776.
Floodplain lakes are ecosystems characterised by annual flood and dry cycles. Fish ecology is influenced by the flood pulse due to the large influx of allochthonous food resources and diversification of habitats during the flood cycle, while during the dry cycle, fishes tend to be confined in reduced habitat. The aim of this study was to evaluate the seasonal variation in trophic niche width and overlap of four species—Mylossoma duriventre, Prochilodus nigricans, Cichla.pleiozona and Serrasalmus rhombeus—in an Amazonian floodplain lake. Stable isotope analyses were used to estimate trophic niche width and overlap during the flood and dry seasons. We hypothesised broader niche width for all species during the flood cycle and a higher degree of overlap between the two piscivorous fishes during the dry cycle. Isotopic niche width was 72% broader for P. nigricans, 61% for S. rhombeus and 54% for C. pleiozona during the dry cycle, which did not support our hypothesis. Core niche width overlaps were not observed between piscivorous species in either flood or dry cycle. The results indicate that seasonal variation in isotopic niche width is specific to feeding habit. Understanding how fish trophic ecology responds to changes in the hydrological regime during the seasons is crucial for sustainable fishery management in a region where many people rely heavily on fish for nutritional and economic purposes.  相似文献   
777.
Genetic Resources and Crop Evolution - Physalis angulata L. is an American species with edible fruits that stands out for having high nutritional and pharmaceutical value. The species is found in...  相似文献   
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