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71.
Martia Ferreira Ana Maseda Jaime Fbregas Ana Otero 《Aquaculture (Amsterdam, Netherlands)》2008,279(1-4):126-130
The effect of semi-continuous culture on the nutritional value of microalgae was tested in the rotifer Brachionus plicatilis in short-term enrichment experiments. Isochrysis aff. galbana clone T-ISO was cultured semi-continuously with renewal rates from 10 to 50% of the volume of the culture per day and used to feed the rotifers. After 24 h, dramatic differences in dry weight and protein, lipid and carbohydrate contents were observed in the rotifers depending on the renewal rate applied to the microalgal culture. Rotifers fed T-ISO cultured with low renewal rates showed low dry weight and organic content, whereas rotifers fed microalgae from nutrient-sufficient, high renewal rate cultures showed higher dry weight and increases up to 60% in protein, 35% in lipid and 100% in carbohydrate contents. Feed conversion rate (FCR) and organic FCR decreased with increasing renewal rates, indicating a more efficient assimilation of the microalgal biomass obtained at high growth rates. The fatty acid profile of rotifers reflected that of T-ISO, with maximum content of polyunsaturated fatty acids (PUFAs), n-3 fatty acids and docosahexaenoic acid (DHA) being found in the rotifers fed microalgae from the renewal rate of 40%. Results demonstrate that the biochemical composition of B. plicatilis is strongly modified through the use of semi-continuous cultures of microalgae in short-term enrichment processes. This technique provides an excellent tool to improve the nutritional value of the live feed used in fish larvae cultures. 相似文献
72.
73.
Sarabia J Sánchez-Barbudo I Siqueira W Mateo R Rollán E Pizarrod M 《Avian diseases》2008,52(3):540-543
We describe lesions in 29 adult domestic pigeons (Columba livia) poisoned with chlorophacinone, an indandione anticoagulant rodenticide. Birds were found dead in the field and in dovecotes after a wide-area treatment against common voles (Microtus arvalis) based on the dispersion in the open field of wheat grain treated with 0.005% chlorophacinone. At necropsy, most pigeons showed crops full of red-colored wheat grain, extensive subcutaneous hematoma in neck and breast zones, and hemorrhages in lungs and the coelomic cavity. Chlorophacinone was determined in liver samples by high-performance liquid chromatography with ultraviolet detection, and the mean (range) concentration was 11.2 (1.48-50.1) microg/g. Pigeons have a venous subcutaneous plexus in the neck zone (plexus venosus subcutaneus collaris), which has been described as an erectile tissue with a thermoregulation function. This case report describes a relationship between the subcutaneous hemorrhagic lesions and the plexus venosus collaris. 相似文献
74.
Sánchez-Carvajal Jose M. Rodríguez-Gómez Irene M. Carrasco Librado Barranco Inmaculada Álvarez Belén Domínguez Javier Salguero Francisco J. Gómez-Laguna Jaime 《Veterinary research communications》2019,43(3):187-195
Veterinary Research Communications - The emergence of virulent strains of porcine reproductive and respiratory syndrome virus (PRRSV), causing atypical and severe outbreaks, has been notified... 相似文献
75.
Context
Although small isolated habitat patches may not be able to maintain a minimum viable population, small patches that are structurally isolated may be functionally connected if individuals can cross the gaps between them, in which case, their areas could be added to form a larger habitat patch, eventually surpassing the size threshold for holding a viable population.Objectives
We studied whether models based on the size and isolation of habitat patches could be used to predict the distribution of the Chestnut-throated Huet-Huet (Pteroptochos castaneus) in fragmented landscapes of the coastal range of the Maule region, central Chile.Methods
We selected seven 10,000-ha landscapes (8.4–70.7% forest cover). For each habitat patch we made 18 predictions of the presence of the species based on the combination of two thresholds: three critical patch sizes for maintaining a viable population (62.5, 125 and 250 ha) and six critical isolation distances between patches (0, 10, 50, 100, 150 and 200 m). We used playbacks in 59 sampling points to estimate the species’ presence/absence. We used logistic regressions to test whether the output of the patch-matrix models could explain part of the variation in the presence of Pteroptochos castaneus.Results
The best predictions for the presence of P. castaneus were obtained with the most conservative scenarios (125–250 ha to 0–10 m), including a positive effect of the understory cover and a lack of effect of the forest type (native or exotic).Conclusions
Our findings suggest that the long term persistence of P. castaneus may depend on the existence of large and/or very connected forest tracts.76.
The computed tomographic “tree‐in‐bud” pattern: Characterization and comparison with radiographic and clinical findings in 36 cats 下载免费PDF全文
77.
78.
Thirty-fourformae speciales (ff.sp.) ofFusarium oxysporum which have been subjected to vegetative compatibility group (VCG) analysis are listed, along with their updated 3-digit numerical
codes. Ten of these ff.sp. are listed for the first time, bringing to 49 the total number of VCG-analyzed, listed ff.sp. New
and corrected entries are tabulated for the remaining 24 ff.sp. 相似文献
79.
Evidence of Migration and Endophytic Presence of Agrobacterium tumefaciens in Rose Plants 总被引:2,自引:0,他引:2
Rubén Martí Jaime Cubero Antonio Daza Jaime Piquer Carmen I. Salcedo Clara Morente María M. López 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(1):39-50
Agrobacterium tumefaciens was isolated from stem tumors of several rose cultivars showing that the bacterium is the causal agent of aerial galls in rose plants. No differences were observed in the characteristics of the Agrobacterium isolates from crown or aerial galls. Stem inoculation of ten rose cultivars showed that all of them were susceptible to A. tumefaciens but differences in the size of the resulting tumors were observed. The movement of A. tumefaciens in rose plants was demonstrated using two wild type strains and two antibiotic resistant mutants. Three months after inoculation, the inoculated strains were recovered in the roots, crown and below and above the inoculation site but low numbers of pathogenic Agrobacterium cells were isolated. New tumors appeared in 5% of the noninoculated wounds. A. tumefaciens was isolated from the stem at different distances from the tumor in naturally infected plants. In symptomless commercial plants, the isolation from the roots, crown and at different stem levels demonstrated the existence of systemic and latent infections in rose. Direct isolation using a nonselective and selective media with or without a previous enrichment step were efficient methods for isolating tumorigenic Agrobacterium from the different parts of rose plants. 相似文献
80.