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51.
C. Castrillo F. Vicente & J. A. Guada 《Journal of animal physiology and animal nutrition》2001,85(7-8):237-241
Energy and nitrogen losses in the urine were recorded in 134 individual balances with adult (1- to 2-year-old) female Beagles that were fed 23 dry extruded dog foods ranging in crude protein (CP) content from 242 to 360 g/kg dry matter. The energy equivalent of urinary nitrogen was estimated as 33.9 kJ/g N. Both energy losses in the urine corrected for the nitrogen balance, and the metabolizable energy (MEn): digestible energy (DE) ratio were found to be closely related to diet CP content (r : 0.851 and 0.820). The MEn content of extruded dog foods can be accurately calculated from the DE content, either by subtracting 4.59 MJ/kg CP or estimating the MEn/DE ratio from the food CP content by the following equation: MEn/DE=0.98 – 3.44 ± 0.517 × CP (kg/MJ DE). 相似文献
52.
Wade O. Watanabe Simon C. Ellis Eileen P. Ellis Vicente Gracia Lopez Paul Bass John Ginoza Aaron Moriwake 《Journal of the World Aquaculture Society》1996,27(3):323-331
Two 10-day hatchery experiments were conducted to evaluate s-type (Hawaiian strain) and ss-type (Thailand strain) rotifers Brachionus plicatilis and cryogenically preserved oyster Crassostrea gigas trochophores as first feeds for larval Nassau grouper Epinephelus striatus. Newly hatched grouper larvae were reared at densities of 11.2–20.8/L in 500-L tanks at 36–38 ppt salinity, 25–26 C, and under a 11-h light: 13-h dark photoperiod. Beginning on day 2 posthatching (d2ph), prey were maintained at a density of 20 individuals/mL, while phytoplankton (Nanochloropsis oculata) was maintained at 500 × 103 cells/mL. In experiment 1, survival and growth were higher (P < 0.05) for fish fed small s-type rotifers (mean lorica length = 117 μm; fish survival = 7.96%) selected by sieving than for fish fed non-selected rotifers (mean lorica length = 161 μm; fish survival = 2.13%). These results demonstrated the advantage of small prey size and suggested that super-small (ss-type) rotifer strains would be beneficial. In experiment 2, three feeding regimens were compared: 1) ss-type rotifers (mean lorica length = 147 μm); 2) oyster trochophores (mean diameter = 50 μm) gradually replaced by ss-type rotifers from d5ph; and 3) a mixed-prey teatment of 50% oyster trochophores and 50% ss-type rotifers. Survival was higher (P < 0.05) for larvae fed mixed prey (15.6%) than for those fed rotifers (9.73%) or trochophores and rotifers in sequence (2.55%), which also showed the slowest growth. Oyster trochophores, although inadequate when used exclusively, enhanced survival when used in combination with rotifers, possibly by improving size selectivity and dietary quality. In a pilot-scale trial, larvae were cultured through metamorphosis in two 33.8-m3 outdoor tanks. Fertilized eggs were stocked at a density of 10 eggs/L and larvae were fed ss-type rotifers from d2ph-d20ph, newly hatched Artemia from d15ph-d18ph, 1-d-old Artemia nauplii from d18ph-d62ph. Survival on d62ph was 1.17%, with a total of 5,651 post-metamorphic juveniles produced. 相似文献
53.
Summary Some pharmacokinetic parameters of an ampicillin/sulbactam (2:1) combination were studied in six goats, after intravenous and intramuscular injection at a single dosage of 20 mg/kg bodyweight (13.33 mg/kg of sodium ampicillin and 6.67 mg/kg of sodium sulbactam). The drugs were distributed according to an open two‐compartment model. The apparent volumes of distribution calculated by the area method of ampicillin and sulbactam were 0.34 ± 0.04 l/kg and 0.45 ± 0.15 1/kg, respectively, and the total body clearances were 0.72 ± 0.11 and 0.38 ± 0.07 l/kg.h. The half‐lives of ampicillin after intravenous and intramuscular administration were 0.32 ± 0.04 h and 0.71 ± 0.14 h, respectively. For sulbactam the half‐lives were 0.79 ± 0.18 h and 1.13 ± 0.21 h after administration by the same routes. The bioavailability after intramuscular injection was high and similar for both drugs (98,29% for ampicillin and 101.84% for sulbactam). The mean peak plasma levels of ampicillin (0.43 ± 0.27 h) and sulbactam (0.34 ± 0.14 h) were reached at a similar time, and peak concentrations were also similar and non‐proportional to the dose of the products administered (11.02 ± 3.11 mg/l of ampicillin and 9.5 ± 0.98 mg/l of sulbactam). 相似文献
54.
Milagros R. de la Peña Annie Villa Franco Hermoso P. IgcasanJr Mary Dianne Grace N. Arnaldo Ramil M. Piloton Soledad S. Garibay Vicente T. Balinas 《Aquaculture International》2018,26(4):1119-1134
The optimum culture conditions of the local strain Chaetoceros calcitrans were determined to improve biomass and reduce cost of production. Under outdoor culture conditions, higher cell density was attained when the cultures were enriched with Tungkang Marine Research Laboratory (TMRL) medium composed of cheap technical grade reagents and cultured at 25 g L?1 salinity. The cultures were lighted with two 40 W cool-white GE fluorescent tubes (24–35 μmol photon m?2 s?1). Using semi-continuous culture system under established optimum culture conditions, C. calcitrans can be re-cultured thrice and concentrated at each culture cycle using electrolytic flocculation method to produce 4.6 kg m?3 of diatom paste. The viability of concentrated C. calcitrans after 3 months of storage was comparable to live diatom cells. Simple preservation technique by low-temperature storage is convenient for storing algal concentrates for use as starter cultures and for feeding invertebrates. The paste costs USD 8.24 kg?1 inclusive of the assets and flocculation materials for culturing and harvesting the diatom, respectively. This study established the suitable conditions for mass culture of C. calcitrans and produced concentrated diatoms in paste form that is readily available for aquaculture hatcheries at a lower cost. 相似文献
55.
正Mating disruption(MD) is an effective environmentallyfriendly control method against the striped rice stem borer(RSB), Chilo suppressalis(Lepidoptera: Crambidae). In this study, the current MD dispensers release the pheromone exponentially, with higher initial release rates that decrease throughout the time. To adjust the timing of dispensers' deployment and evaluate the importance of controlling the early first or the second male flight, 相似文献
56.
Field DB Baumgartner TR Charles CD Ferreira-Bartrina V Ohman MD 《Science (New York, N.Y.)》2006,311(5757):63-66
It is currently unclear whether observed pelagic ecosystem responses to ocean warming, such as a mid-1970s change in the eastern North Pacific, depart from typical ocean variability. We report variations in planktonic foraminifera from varved sediments off southern California spanning the past 1400 years. Increasing abundances of tropical/subtropical species throughout the 20th century reflect a warming trend superimposed on decadal-scale fluctuations. Decreasing abundances of temperate/subpolar species in the late 20th century indicate a deep, penetrative warming not observed in previous centuries. These results imply that 20th-century warming, apparently anthropogenic, has already affected lower trophic levels of the California Current. 相似文献
57.
Abelardo Gutiérrez Vicente Ruiz Enrique Moltó Gervasio Tapia Maria del Mar Téllez 《Crop Protection》2010
The Red Palm Weevil (Rhynchophorus ferrugineus Olivier) is one of the worst pests for palms, since it can completely destroy the plant. Its early detection is very difficult and when the action of the pest is discovered, normally it is too late for recovering the plant. Bioacoustic sensors provide a good alternative for early detection of this pest because larvae activity is audible while they excavate tunnels to feed. This work describes the different stages for the development of an original electronic device based on acoustic sensors for early detection of Red Palm Weevil larvae in the interior of palms. This device is based on characteristic frequencies possibly related to their feeding activity. The performed tests have demonstrated that is possible to detect two week old larvae activity studying the sound intensity around 2250 Hz in palms infested only with 5 individuals under controlled environmental conditions. The activity of other insects artificially situated in the interior of palms did not affect the response of the device, possibly because they produce different frequencies (in the range 5–7 kHz). Future work will be aimed at assessing the infestation levels. 相似文献
58.
Bovine tuberculosis (bTB) is caused by Mycobacterium bovis and closely related mycobacteria of the Mycobacterium tuberculosis complex. They have an extensive host range and may cause zoonotic TB. A major obstacle to bTB eradication in livestock is the implication of wildlife in the natural cycle of the pathogen. The identification of wildlife reservoir hosts is crucial for the implementation of effective control measures. The European wild boar (Sus scrofa) is frequently considered a spillover or dead end host rather than a true reservoir, and scientific evidence is conflicting outside Mediterranean Spain. The aim of this review is to update current scientific evidence of the wild boar as a TB reservoir and to underline those aspects that need further research. Evidences supporting that wild boar is a TB reservoir host include: (i) presence of common M. tuberculosis complex genotypes in wild boar, domestic and wild animals and humans, (ii) high prevalence of M. bovis among wild boar in estates fenced for decades in complete absence of contact with domestic livestock, and other wild ungulates (iii) TB lesions are frequently seen in thoracic lymph nodes and lungs, suggesting that respiratory infection and excretion may occur, and (iv) extensive tuberculous lesions in more than one anatomical region occur in a high proportion of juvenile wild boar that probably represents the main source of mycobacterial excretion. Hence, epidemiological, pathological and microbiological evidence strongly suggests that, at least in Spanish Mediterranean ecosystems, wild boar are able to maintain TB infection in the wild and are most probably able to transmit the disease to other species, acting as a true wildlife reservoir. These results expand the list of wildlife species that act as natural reservoirs of TB in different parts of the world and suggest the need to control the infection in wild boar populations for the complete eradication of the disease in Spain. 相似文献
59.
Papuamide A is representative of a class of marine derived cyclic depsipeptides, reported to have cytoprotective activity against HIV-1 in vitro. We show here that papuamide A acts as an entry inhibitor, preventing human immunodeficiency virus infection of host cells and that this inhibition is not specific to R5 or X4 tropic virus. This inhibition of viral entry was determined to not be due to papuamide A binding to CD4 or HIV gp120, the two proteins involved in the cell-virus recognition and binding. Furthermore, papuamide A was able to inhibit HIV pseudotype viruses expressing envelope glycoproteins from vesicular stomatitis virus or amphotropic murine leukemia virus indicating the mechanism of viral entry inhibition is not HIV-1 envelope glycoprotein specific. Time delayed addition studies with the pseudotyped viruses show that papuamide A inhibits viral infection only at the initial stage of the viral life cycle. Additionally, pretreatment studies revealed that the virus, and not the cell, is the target of papuamide A’s action. Together, these results suggest a direct virucidal mechanism of HIV-1 inhibition by papuamide A. We also demonstrate here that the other papuamides (B-D) are able to inhibit viral entry indicating that the free amino moiety of 2,3-diaminobutanoic acid residue is not required for the virucidal activity. 相似文献
60.
Ballester-Sánchez Jaime Gil Jose Vicente Haros Claudia Monika Fernández-Espinar María Teresa 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(2):185-191
Plant Foods for Human Nutrition - Interest in quinoa as a functional food ingredient is currently emerging. The flours from white, red and black quinoa seeds were analysed in terms of total... 相似文献