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81.
Barbarito J. Jaime-Ceballos Alfredo Hernndez-Llamas Tsai Garcia-Galano Humberto Villarreal 《Aquaculture (Amsterdam, Netherlands)》2006,260(1-4):215-220
The nutritional response of Litopenaeus schmitti larvae to substitution of Chaetoceros muelleri by Spirulina platensis meal (SPM) was evaluated. The substitution levels (S) were 0%, 25%, 50%, 75% and 100%, dry weight basis. Final larval length (FL) ranged from 1.98 to 3.16 mm for the different substitution levels. There was a significant relationship between S and FL, described by the following quadratic equation: FL = 2.853 + 0.01598S − 0.000233S2. The substitution level (S) yielding maximum FL was 34.2%. Development index (DI) values ranged from 2.84 to 3.93 and were dependent on substitution level. The corresponding equation was DI = 3.799 + 0.00945S − 0.000189S2 (P < 0.01). Maximum DI was obtained at 25.0% substitution. Survival was high (82–87%) and no significant differences were found between treatments. Protein digestibility of either microalgae was high, with 92% for SPM and 94% for C. muelleri, with no significant differences between them. The results in this study indicate that an adequate balance of nutrients in relation to the requirements of the species is critical. To simultaneously improve FL and DI, a 30% substitution of C. muelleri by SPM is suggested. This is equivalent to feeding 0.15 mg larvae− 1 day− 1 dry weight basis of a 70% C. muelleri/30% SPM diet, representing 0.078 mg protein larvae− 1 day− 1, 0.026 mg lipids larvae− 1 day− 1 and 2.732 J larvae− 1 day− 1. 相似文献
82.
Alfredo Campa a-Torres Luis R. Martinez-Cordova Humberto Villarreal-Colmenares Roberto Civera-Cerecedo 《Aquaculture (Amsterdam, Netherlands)》2005,250(3-4):748-754
Dry matter and protein digestibility of three plant-derived and four animal-derived feedstuffs and diets in which they were included were evaluated for juvenile Australian redclaw. The ingredients evaluated were: soy paste, textured wheat, sorghum meal, two sardine meals (67% and 58% crude protein), squid meal, and red crab meal. A reference diet was formulated and produced in the CIBNOR nutrition laboratory. Seven experimental diets were then made including 15% of each ingredient in the reference diet. The experiment consists of a single-factor, completely randomized design with five replicates per treatment. Digestibility was measured indirectly, using chromic oxide as a marker. Plant-derived ingredients and the corresponding diets had, in general, a higher digestibility than animal ingredients. Soy paste and sorghum meals, and the diets in which they were included, showed an excellent dry matter (over 87%) and protein (approximately 90%) digestibility. Some of the animal ingredients such as sardine meal 67% CP and squid meal had a good dry matter digestibility (over 80%), but were significantly lower than plant-derived ingredients. The lowest dry matter and protein digestibility was recorded for sardine meal 58% CP and red crab meal. It is concluded that juvenile redclaw are omnivorous and able to efficiently consume diets containing plant- and animal-derived ingredients, but they can digest plant-derived ingredients more efficiently. 相似文献
83.
Alfredo Hernandez-Llamas Alfredo Gonzalez-Becerril Sergio Hernandez-Vazquez & Sergio Escutia-Zuñiga 《Aquaculture Research》2004,35(2):103-111
A bioeconomic approach was used to evaluate random variation of growth and mortality parameters and feed conversion ratio (FCR) for intensive production of the blue shrimp Litopenaeus stylirostris (Stimpson). Severe mortality problems caused by high impact diseases were not considered in this analysis. For a 50‐ha farm, the maximum values of the internal rate of return (IRR=44%) and net revenue above operation costs (NR=US$1 211 000) were obtained for a stocking density of 67 postlarvae (PL) m?2 during winter–spring (cycle 1) and 65 PL m?2 during summer–autumn (cycle 2). Regardless of the density used for cycle 1, stocking at 50 and 65 PL m–2 for cycle 2 sufficed to obtain, respectively, IRRs greater than the minimum attractive IRRs of 15% and 30%. A frequency distribution of IRR, projected for densities of 67 and 65 PL m?2, showed high confidence in obtaining IRR values above 15% and 30% (i.e. confidence >99% and 92% respectively). The frequency distribution of NR showed that the farm could operate without economic losses. Stocking a minimum of 53% of the capacity of the farm would guarantee positive NR. Sensitivity analysis indicated that the IRR and NR were mainly influenced by mortality rate, selling price, density, final weight and FCR. 相似文献
84.
Objective: To determine whether in healthy horses and those with colic, exposure of peritoneal fluid to room air affects values obtained on biochemical analysis. Study Design: Prospective study. Animals: Adult horses with a primary complaint of acute abdominal pain (n=29) and 12 healthy horses. Methods: Peritoneal fluid was aseptically collected under aerobic and anaerobic conditions. After collection, pH, PCO2, PO2, HCO3?, Na+, ionized Ca2+, K+, lactate, and glucose were immediately measured using a commercial blood gas analyzer. Biochemical variables were compared between aerobically and anaerobically obtained samples using a paired t‐test. Results: In healthy horses, peritoneal fluid samples collected under anaerobic conditions had higher PCO2 and ionized Ca2+ and lower PO2, HCO3?, and pH compared with samples exposed to air. No differences were observed for K+, Na+, glucose, and lactate. In horses with colic, samples collected anaerobically had higher PCO2, ionized Ca2+, Na+, and glucose and lower PO2, HCO3?, and pH value compared with samples exposed to air. No differences were observed for K+ and lactate. Conclusion: Exposure of peritoneal fluid to room air had a significant effect on pH, PCO2, PO2, and variables associated or dependent on changes in pH such as HCO3? and ionized Ca2+. Interpretation of biochemical analysis of peritoneal fluid may be influenced by sample collection method. 相似文献
85.
Montaño A Beato VM Mansilla F Orgaz F 《Journal of agricultural and food chemistry》2011,59(4):1301-1307
The content of organosulfur compounds was determined in selected garlic cultivars grown at four locations in Andalusia, Spain. The organosulfur compounds studied were three γ-glutamyl peptides, namely, γ-l-glutamyl-S-(2-propenyl)-l-cysteine (GSAC), γ-l-glutamyl-S-(trans-1-propenyl)-l-cysteine (GSPC), and γ-l-glutamyl-S-methyl-l-cysteine (GSMC), and four cysteine sulfoxides (alliin, isoalliin, methiin, and cycloalliin). There was a significant effect of the location, cultivar, and garlic ecotype on individual organosulfur compound contents. Purple-type cultivars showed on average the highest contents of GSMC, GSAC, alliin, and methiin but the lowest isoalliin content. The impact of genotype was relatively high for GSAC, whereas this factor hardly contributed to the total variability in alliin and isoalliin content. Planting date had a significant effect on the content of alliin and isoalliin. Discriminant analysis evidenced the ability of organosulfur compounds to distinguish among garlic bulbs from different locations or ecotypes with 81 or 86% accuracy, respectively. 相似文献
86.
Alfredo Andreeta DChem Claudio Verde DVM Maximo Babusci BVetMed Raul Muller BVetMed Maria I. Simpson BVetMed Maria Fabiana Landoni PhD 《Journal of Equine Veterinary Science》2011,31(9):502-505
The aim of this study was to compare the penetration of diclofenac through horse skin in vitro and its efficacy in vivo when applied from five, commercially available, human medical formulations containing 1.16% diclofenac diethylamine. The rate of transdermal penetration of diclofenac varied between formulations. Also, estimated steady-state flux (Jss) was significantly different from that reported for human and rat skin. All the tested formulations produced a very weak and short-lasting antiedematous effect. 相似文献
87.
Gayo V Cuervo P Rosadilla D Birriel S Dell'Oca L Trelles A Cuore U Mera y Sierra R 《Journal of zoo and wildlife medicine》2011,42(2):354-356
Fascioliasis, the zoonotic disease caused by the trematode Fasciola hepatica, is expanding worldwide, with a 17 million people at risk. Rodents, often recognized as a major source of zoonotic diseases, are affected by F. hepatica, with some species playing important roles in the disease epidemiology. The case reported here in a nutria or kiyá (Myocastor coypus) is the first documented case of F. hepatica in this species in Uruguay. Parasitic burden and total egg production detected are markedly higher than reported previously for this species, confirming its potential role as an effective reservoir and disseminator of liver flukes. Although further research is needed, nutria should be considered when designing effective control programs for fascioliasis. 相似文献
88.
María Inés Mercado María Victoria Coll Aráoz Iván Manrique Alfredo Grau César A. N. Catalán 《Genetic Resources and Crop Evolution》2014,61(6):1209-1217
The sesquiterpene lactones (STLs) content of glandular trichomes from the leaves of twenty-five yacon (Smallanthus sonchifolius, Asteraceae) accessions, obtained along a latitudinal gradient from Ecuador to northwest Argentina, was characterized by gas chromatography/mass spectroscopy (GC/MS). While accessions from Ecuador, Bolivia and Argentina proved to be very chemoconsistent, significant variation was found in quantitative composition of STLs from accessions in central Peru, the probable region of origin for the species. 相似文献
89.
Beato VM Orgaz F Mansilla F Montaño A 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):218-223
The contents of total phenolic compounds, flavonoids, and phenolic acids were determined in selected garlic cultivars grown
at four locations. The total phenolic content varied from 3.4 mg gallic acid equivalents (GAE)/g of dry matter (dm) to 10.8 mg
GAE/g of dm with a mean value of 6.5 mg GAE/g of dm. The myricetin, quercetin, kaempferol, and apigenin flavonoids were not
detected in any of the samples. Caffeic acid and ferulic acid were the major phenolic acids found with mean values of 2.9 mg/kg
of dm and 2.6 mg/kg of dm, respectively. The mean contents of vanillic, p-hydroxybenzoic, and p-coumaric acids were comparable (0.4–0.8 mg/kg of dm), and the level of sinapic acid was negligible (< 0.1 mg/kg of dm). There
was a significant effect of location but an insignificant effect of genotype on contents of caffeic, vanillic, p-hydroxybenzoic, and p-coumaric acids. However, genotype but not location affected the contents of total phenolics and ferulic acid. On average,
the white garlic cultivars and Chinese garlic cultivars contained higher contents of total phenolics and ferulic acid than
the purple garlic cultivars. However, the differences in the total phenolic content between the purple and white garlic cultivars
were not significant. 相似文献
90.
Vitamin content and amino acid composition of pickled garlic processed with and without fermentation 总被引:7,自引:0,他引:7
Montaño A Casado FJ de Castro A Sánchez AH Rejano L 《Journal of agricultural and food chemistry》2004,52(24):7324-7330
The effect of processing, with and without fermentation, upon the nutritional composition of pickled garlic was evaluated. On a dry basis, the fermented product had a higher content of riboflavin, alpha-tocopherol, and most individual amino acids but a lower thiamin level than the unfermented product. Ascorbic acid was totally lost during processing. The chemical scores for the unfermented and fermented product were 88 and 108%, respectively, with the limiting amino acid being leucine. Water blanching (90 degrees C for 4 min) affected only the ascorbic acid content, whereas fermentation significantly affected the contents of thiamin, ascorbic acid, and alpha-tocopherol, as well as glutamic acid and arginine. For each processing type, the effect of the preservation method and storage time on vitamins and amino acid composition was also analyzed. In the case of the fermented product, usage of the corresponding fermentation brine plus refrigerated storage was also assayed as the packing/preservation method and was found to give the best result from a nutritional standpoint. 相似文献