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151.
Daily rhythmicity in nutrient content of asinine milk   总被引:2,自引:0,他引:2  
Asinine (donkey) milk has been proposed as an alternative to bovine (cow) milk for consumption by human infants who are allergic to bovine milk proteins. To expand the current knowledge of asinine lactation, we investigated daily rhythmicity in the concentration of major constituents of asinine milk. We observed no daily rhythmicity in somatic cell count and pH but observed robust rhythmicity in lipid, lactose, and protein content (robustness greater than 70%, p < 0.01). Lipid and lactose content peaked during the night, whereas protein content peaked during the day. Lipid content of asinine milk was lower than that of human milk, and asinine milk resembled human milk better than bovine milk regarding sugar and protein content.  相似文献   
152.
Background: The aim of this trial was to investigate the effects of different inclusion levels of a partial y defatted black soldier fly(BSF, Hermetia il ucens L.) larva meal on the growth performance, nutrient digestibility, blood profile, gut morphology and histological features of piglets. A total of 48 newly weaned piglets were individual y weighed(initial body weight(IBW): 6.1 ± 0.16 kg) and randomly al ocated to 3 dietary treatments(4 boxes as replicates/treatment and 4 animals/box). BSF larva meal was included at increasing levels(0% [BSF0], 5% [BSF5] and 10% [BSF10]) in isonitrogenous and isoenergetic diets formulated for two feeding phases: I(from d 1 to d 23) and I(from d 24 to d 61). The weight gain(WG), average daily gain(ADG), average daily feed intake(ADFI) and feed conversion ratio(FCR) were calculated for each feeding phase and for the whole trial. The haematochemical parameters and nutrient digestibility of the piglets were also evaluated. A total of 3 piglets per box were slaughtered on d 61 and the slaughtered piglets were submitted to morphometric investigations and histopathological examinations.Results: No overal significant differences were observed for growth performance(P 0.05), except for the ADFI of phase I, which showed a linear response to increasing BSF meal levels(P 0.05, maximum for the BSF10 group). Dietary BSF meal inclusion did not significantly influence the blood profile, except as far as monocytes and neutrophils are concerned,and these showed a linear and quadratic response, respectively, to increasing BSF meal levels(P 0.05, maximum for the BSF10 and BSF5 groups, respectively). On the other hand, the nutrient digestibility, gut morphology and histological features were not affected by dietary BSF meal inclusion(P 0.05).Conclusions: The obtained results show that a partial y defatted BSF larva meal can be used as a feed ingredient in diets for weaned piglets without negatively affecting their growth performance, nutrient digestibility, blood profile, gut morphology or histological features.  相似文献   
153.
Background: The present work aimed at evaluating the effect of the dietary replacement of soybean oil(S) by two types of insect fats extracted from black soldier fly larvae(H, Hermetia il ucens L.) and yel ow mealworm larvae(T, Tenebrio molitor L.) on growth performance, nutrient digestibility, blood parameters, intestinal morphology and health of growing rabbits.Methods: At weaning, 200 crossbred rabbits(36 days old) were allotted to five dietary treatments(40 rabbits/group): a control diet(C) containing 1.5% of soybean oil and four experimental diets where soybean oil was partially(50%) or totally(100%) substituted by H(H50 and H100) or T(T50 and T100) fats. Total tract digestibility was evaluated on 12 rabbits per treatment. The growth trial lasted 41 d and, at slaughtering(78 days old), blood samples were collected from 15 rabbits per treatment, morphometric analyses were performed on duodenum, jejunum and ileum mucosa,and samples of liver, spleen and kidney were submitted to histological evaluation.Results: No difference was observed between the control and the experimental groups fed insect fats in terms of performance, morbidity, mortality and blood variables. The addition of H and T fats did not influence apparent digestibility coefficients of dry matter, protein, ether extract, fibre fractions and gross energy. Gut morphometric indices and organ histopathology were not affected by dietary inclusion of H and T fats.Conclusions: H and T fats are suitable sources of lipid in rabbit diets to replace soybean oil without any detrimental effect on growth performance, apparent digestibility, gut mucosa traits and health.  相似文献   
154.
Leptin is an anorectic hormone secreted mainly by peripheral adipocytes but also by other central and peripheral tissues. It acts by means of a receptor called OB‐R, influencing not only appetite and body mass but being also involved in many fields like endocrinology, metabolism and reproduction. Immunohistochemistry and qRT‐PCR techniques were, respectively, used to demonstrate the presence of leptin and its receptor in the gut of adult zebrafish and to evaluate the leptin gene expression response to feeding and fasting. Immunoreactivity for the antibodies utilized was demonstrated in feeding but not in fasting fish, and the gene expression analysis corroborates the data obtained by immunohistochemistry. Therefore, all the obtained results support the hypothesis of the role of this hormone in food regulation in zebrafish.  相似文献   
155.
156.
Oil of bergamot is receiving renewed popularity in aromatherapy. The biovariability of Citrus bergamia grown wild in Calabria (Italy) was investigated as far as chemical markers (linalool, linalyl acetate and bergapten) content and antioxidant and antifungal activities of the methanolic extracts. The average content in the markers presents slight variations with the altitude and more evident changes with the latitude of the areas of plant collection.  相似文献   
157.
The antioxidant activity of the methanol extract of Hypericum triquetrifolium Turra (Hypericaceae) aerial part and of flavonoids isolated therein, I3,II8-biapigenin, quercetin-3-O-galactoside, kaempferol-3-O-glycoside, (-)-epicatechin and hypericin, was evaluated. The IC(50) resulted between 0.062 and 1 mg/ml.  相似文献   
158.
Nine samples of Glycyrrhiza glabra were collected in various sites of Calabria, Italy, with the aim to determine the variability in the confront of active constituents and in antibacterial and antifungal activities of the extracts. The samples showed remarkable differences in chemical composition and biological activity.  相似文献   
159.
This paper deals with the characterization of 475 Sicilian virgin olive oils (VOO) produced in 10 different crop years (from 1993 to 2004), according to the cultivar and the geographical origin by means of multivariate statistical analysis applied to fatty acids. In particular, the studied VOOs came from the Peloritana and Maghrebian geological zones. The fatty acid composition was determined by using the official gas chromatographic method. The results suggest that although the effect of the cultivar is significant in the olive oil classification based on the fatty acid composition, a predominant and well-defined geographic effect is also present. This study demonstrated that it is possible to employ an official and inexpensive analytical method coupled with the statistical analysis to ascertain the geographical origin and the cultivar of an extra virgin olive oil.  相似文献   
160.
The present article reports the antimicrobial efficacy of four monoterpenes (thymol, carvacrol, p-cymene, and gamma-terpinene) against the Gram-positive bacterium Staphylococcus aureus and the Gram-negative bacterium Escherichia coli. For a better understanding of their mechanism of action, the damage caused by these four monoterpenes on biomembranes was evaluated by monitoring the release, following exposure to the compounds under study, of the water-soluble fluorescent marker carboxyfluorescein (CF) from large unilamellar vesicles (LUVs) with different lipidic composition (phosphatidylcholine, PC, phosphatidylcholine/phosphatidylserine, PC/PS, 9:1; phosphatidylcholine/stearylamine, PC/SA, 9:1). Furthermore, the interaction of these terpenes with dimyristoylphosphatidylcholine multilamellar vesicles as model membranes was monitored by means of differential scanning calorimetry (DSC) technique. Finally, the results were related also with the relative lipophilicity and water solubility of the compounds examined. We observed that thymol is considerably more toxic against S. aureus than the other three terpenes, while carvacrol and p-cymene are the most inhibitory against E. coli. Thymol and carvacrol, but not gamma-terpinene and p-cymene, caused a concentration-dependent CF leakage from all kinds of LUVs employed; in particular, thymol was more effective on PC and PC/SA LUVS than on PC/PS vesicles, while carvacrol challenge evoked a CF leakage from PC/PS LUVs similar to that induced from PC/SA LUVs, and lower than that measured with PC vesicles. Concerning DSC experiments, these four terpenes caused a decrease in Tm and (especially carvacrol and p-cymene) DeltaH values, very likely acting as substitutional impurities. Taken together, our findings lead us to speculate that the antimicrobial effect of thymol, carvacrol, p-cymene, and gamma-terpinene may result, partially at least, from a gross perturbation of the lipidic fraction of the plasmic membrane of the microorganism. In addition to being related to the physicochemical characteristics of the compounds (such as lipophilicity and water solubility), this effect seems to be dependent on the lipidic composition and net surface charge of the microbic membranes. Furthermore, the compounds might cross the cell membranes, thus penetrating into the interior of the cell and interacting with intracellular sites critical for antibacterial activity.  相似文献   
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