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71.
This research aimed to determine the value of esophageal pH in awake and anesthetized dogs, to evaluate the esophageal pH value in awake dogs, in different body positions, as well as to study the occurrence of gastroesophageal reflux episodes in these positions. Thus, 40 healthy male and female adult dogs with mean body weight of 15.5 ± 4.6 kg were used. Esophageal pHmetry was conducted by inserting a catheter through the oropharynx in 30 dogs (stage 1) anesthetized with acepromazine, propofol and isoflurane, submitted to elective ovariosalpingohysterectomy. In addition, 8-h esophageal pHmetry was carried out transnasally in 10 awake dogs (stage 2), allowed to move and change body positions (lateral and sternal decubitus, and standing position), which were recorded. The mean esophageal pH value was lower (p < 0.01) in the anesthetized dogs (7.3 ± 0.82) than in the awake dogs (8.2 ± 0.3). Only four anesthetized dogs (13.33%) suffered reflux episodes. Reflux was not observed in the awake dogs and no esophageal pH differences were found between the body positions studied. Compared to the alert state, general anesthesia in dogs submitted to the previously mentioned anesthesia protocol causes esophageal pH reduction and predisposes to the occurrence of gastroesophageal reflux episodes. Transnasal pHmetry of 8 h in healthy awake dogs reveals that the esophageal pH value is alkaline and does not vary according to body position. In these animals, decubitus position is not a determining factor for reflux episodes to occur.  相似文献   
72.
Phenolic extracts from olive tree leaves and olive pomace were used to enrich refined oils (namely, maize, soy, high-oleic sunflower, sunflower, olive, and rapeseed oils) at two concentration levels (200 and 400 μg/mL, expressed as gallic acid). The concentration of characteristic olive phenols in these extracts together with the lipidic composition of the oils to be enriched influenced the mass transfer of the target antioxidants, which conferred additional stability and quality parameters to the oils as a result. In general, all of the oils experienced either a noticeable or dramatic improvement of their quality-stability parameters (e.g., peroxide index and Rancimat) as compared with their nonenriched counterparts. The enriched oils were also compared with extra virgin olive oil with a natural content in phenols of 400 μg/mL. The healthy properties of these phenols and the scarce or nil prices of the raw materials used can convert oils in supplemented foods or even nutraceuticals.  相似文献   
73.
Abstract

The current study aimed to evaluate the effect of split application of potassium (K) fertilizer on the production and quality of sweet potatoes. Ten treatments were evaluated in factorial design (3?×?3?+?1): three doses of potassium (60, 90, and 120?kg K2O ha?1); three application types (100% applied at planting; 50% applied at planting and 50% was given as topdressing; 25% applied at planting and 75% was given as topdressing) and one control (without the application of K2O either at planting or topdressing). The experiment used a randomized complete block design and four repetitions. The following parameters were studied: root number; root fresh matter per plant; total dry matter; yield; total macronutrient extraction; sugar content of starch; and commercial starch. The production characteristics of the roots presented a significant interaction between the factors doses of potassium and application types (parcelaments). Finally, better results were obtained when potassium was applied 50% at planting and 50% as topdressing.  相似文献   
74.

This work evaluated the effects of food frequencies and self-feeding on the behavior, performance, and blood biochemistry of Colossoma macropomum. Juveniles weighing 3.63?±?0.05 g were distributed in 27 aquariums (40 L), with six fish per aquarium, to evaluate nine treatments in three replications in a 12L:12D photoperiod. The treatments were 24-h self-feeding (SF); daytime self-feeding at will (SFD); nighttime self-feeding at will (SFN); and feeding at fixed frequencies of two (2D), four (4D), and six times (6D) daytime and twice (2 N), four (4 N), and six times (6 N) nightly. The treatments were offered in automatic feeders, with fixed frequencies programmed. Extruded commercial feed, with 46% protein, was used. The experimental period was 40 days. In the SF treatment, the animals exhibited 95.7% nocturnal and 4.3% diurnal feeding activity (p?<?0.05). In the treatment SFD and SFN, the animals showed feeding activity throughout the day and night. Final weight, weight gain, and total feed intake were higher for animals at fixed daytime and nighttime frequencies (p?<?0.05). Feed conversion was better for animals in SF, SFD, 4D, SFN, and 4 N (0.89, 0.76, 0.91, 0.85, and 0.88, respectively) (p?<?0.05). Cholesterol and high-density lipoproteins were lower for fish in SF, SFN, 2 N, 4 N, and 6 N (p?<?0.05). SF treatment animals had lower triglyceride content, 154.20 mg dL?1 (p?<?0.05). Colossoma macropomum has nocturnal food preferences, however, with remarkable plasticity. Juveniles of this species fed four times during the day or night show good performance. Dietary patterns influenced the blood metabolic indicators of this species and the periods studied.

  相似文献   
75.
Harmful Algal Blooms (HABs) constitute one of the most important sources of contamination in the oceans, producing high concentrations of potentially harmful biotoxins that are accumulated across the food chains. One such biotoxin, Okadaic Acid (OA), is produced by marine dinoflagellates and subsequently accumulated within the tissues of filtering marine organisms feeding on HABs, rapidly spreading to their predators in the food chain and eventually reaching human consumers causing Diarrhetic Shellfish Poisoning (DSP) syndrome. While numerous studies have thoroughly evaluated the effects of OA in mammals, the attention drawn to marine organisms in this regard has been scarce, even though they constitute primary targets for this biotoxin. With this in mind, the present work aimed to provide a timely and comprehensive insight into the current literature on the effect of OA in marine invertebrates, along with the strategies developed by these organisms to respond to its toxic effect together with the most important methods and techniques used for OA detection and evaluation.  相似文献   
76.
77.
The effects of different simulated rainfall regimes on water relations, growth, and biomass production and allocation of five provenances of Cedrela fissilis, C. saltensis and C. balansae were assessed in a pot-grown seedling experiment in greenhouse under uncontrolled conditions. Four simulated rainfall regimes were applied: 600 mm year?1 (severe water deficit), 800 mm year?1 (mild water deficit), 1,000 mm year?1 (mild wet), and 1,200 mm year?1 (well-watered) used as control. Provenances were compared in terms of water relations (midday leaf water potential, Ψ md and relative water content, RWC), growth (root, shoot and leaf length, neck diameter), growth rate (shoot- and neck growth rate, SGR and NGR), biomass production (root, shoot and leaf dry weight), and biomass allocation (root:shoot ratio, RSR). Multivariate analyses revealed that water relations differed significantly under all simulated rainfall treatments by means of several variables throughout time. Effects of species × treatment, and provenance nested within species × treatment interactions significantly were important. SGR and RSR also were important to explain differences in Ψ md and RWC between treatments and provenances. Broadly C. balansae and C. saltensis provenances seem to display a better performance than C. fissilis provenances under severe water deficit only. However, despite differences between provenances, it was not possible to clearly separate them according to their origin, based on water relations and growth performance. Even though the results of this study performed on pot-grown seedlings are based on relatively few observations and require additional confirmation, they allow an opportunity for speculation on the factors that are related to intraspecific variations that are likely to occur during the growth of seedlings from different geographical sites in field condition.  相似文献   
78.
The contribution of biofilm to water quality and as a food source for the culture of the freshwater shrimp Neocaridina heteropoda heteropoda was assessed in indoor aquaria using a zero water exchange system. Two successive phases were conducted to evaluate biofilm development on different substrates (polyethylene net: PN, plastic bottles: PET, agrovelo: AV) and the effect of biofilm to shrimps culture. The biofilm grown on all substrates helped to keep a good water quality by the uptake of nitrogen compounds and the production of high levels of dissolved oxygen associated to the proliferation of autotrophic microorganisms. High survival, reproduction and hatching of shrimps were achieved in all groups mainly associated with good water quality. Final biomass of the shrimps was significant higher for PN and AV groups; while specific growth rate and the levels of lipids of the shrimps yielded similar values for all treatments indicating that the three substrates allowed the growth of a biofilm that resulted in a healthy food source with similar nutritional value for shrimps. The results show that the production of N. heteropoda heteropoda could be successfully conducted by a biofilm‐based culture system with no water exchange, and thus contributing to a better water use. All materials tested were suitable substrates for biofilm growth, though AV and PET could reduce significantly production costs when compared to the PN. Moreover, by the recycling and reuse of waste materials (such as plastic bottles) could contribute to the development of a responsible, sustainable and environmentally friendly culture method.  相似文献   
79.
以多环芳烃芘和苯并(a)芘为供试物,对多株土著菌和引进菌同时进行筛选试验。结果表明,引进菌经过驯化后对芘和苯并(a)芘都具有一定的降解能力,降解率在30%~80%,通过SPSS数理统计分析软件对数据进行处理后得出,引进细菌B61、B67、M-B和引进真菌Y219、Y220、M-Y作为固定化包埋的菌种;土著菌对芘和苯并(a)芘的降解率可达40%~95%,经过筛选后确定,土著细菌B02、B07、B09和土著真菌F02、F05、F06作为固定化包埋的菌种。通过试验对上述各菌进行了生长曲线的测定,细菌和酵母菌的对数生长期是5~20 h,真菌的对数生长期是10~55 h,这为固定化微生物提供了一定的前提条件。  相似文献   
80.
The daily live weight gain (DLWG), faecal nematode egg counts (FEC), and packed cell volume (PCV) of Suffolk, Ile de France and Santa Inês ewe lambs were evaluated fortnightly for 56 days in the dry season (winter) and 64 days in the rainy season (summer) of 2001-2002. The animals were distributed in two similar groups, one located on Aruana and the other on Tanzania grass (Panicum maximum), in rotational grazing system at the Instituto de Zootecnia, in Nova Odessa city (SP), Brazil. In the dry season, 24 one-year-old ewe lambs were used, eight of each breed, and there was no difference (p > 0.05) between grasses for DLWG (100 g/day), although the Suffolk had higher values (p < 0.05) than the other breeds. In the rainy season, with 33 six-month-old ewe lambs, nine Suffolk, eight Ile de France and 16 Santa Inês, the DLWG was not affected by breed, but it was twice as great (71 g/day, p < 0.05) on Aruana as on Tanzania grass (30 g/day). The Santa Inês ewe lambs had the lowest FEC (p < 0.05) and the highest PCV (p < 0.05), confirming their higher resistance to Haemonchus contortus, the prevalent nematode in the rainy season. It was concluded that the best performance of ewe lambs on Aruana pastures in the rainy season is probably explained by their lower nematode infection owing to the better protein content of this grass (mean contents 11.2% crude protein in Aruana grass and 8.7% in Tanzania grass, p < 0.05) which may have improved the immunological system with the consequence that the highest PCV (p < 0.05) observed in those animals.  相似文献   
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