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971.
The effect of interaction of crude protein level in the diet and coccidiosis of the cecum and small intestine of chicks was investigated. A total of 390 day-old chicks were divided in 36 groups of ten and six groups of five chicks each. Twelve groups of ten and two groups of six chicks each were fed one of the three diets based on dietary crude protein level (16%, 20% and 24%). All diets contained an equal energy concentration. The chicks were on the appropriate diet for 15 days prior to infection. Each group was then subjected to one of the three treatments (a) control, (b) a single dose infection with 100,000 oocysts of Eimeria acervulina and (c) a single dose infection with 10,000 oocysts of Eimeria tenella. On the eighth day post infection all surviving E. tenella infected chicks and two replicates per dietary treatment of control and E. acervulina infected chicks were killed. An increase in dietary crude protein led to a linear (P<0.01) increase in daily gains and feed efficiency but did not affect feed consumption of chicks during one to 15 days pre-infection. Coccidiosis caused a reduction in daily gain, feed consumption and efficiency of feed utilization, the effect being more severe in E. tenella infection. The effect of dietary crude protein was protective against weight reduction. Chicks infected with E. tenella fed 24% crude protein had a higher (P<0.01) mortality rate than those fed on 16% or 20% crude protein level. The oocyst production by E. acervulina infected chicks was also higher (P<0.01) at the 24% crude protein level. The E. acervulina infected chicks exhibited compensatory growth during the eight to 14 days post infection. The compensatory growth was superior at the higher crude protein levels. The mechanism of compensatory growth is discussed.  相似文献   
972.
Heat treatment induces defense mechanisms and triggers physiological responses that allow citrus fruit to withstand stressful conditions during storage. The aim of this paper was to identify changes in the proteome and the biochemistry of Valencia oranges (Citrus sinensis cv Valencia late) subjected to heat treatment before 0, 30 and 60 d of storage at 5 °C. Heat treatment for 48 h at 37 °C and 90% relative humidity was followed by 24 h at 20 °C. Differentially expressed proteins were detected by two-dimensional differential gel electrophoresis and identified by matrix-assisted laser desorption/ionization MS. Twenty eight different proteins in 40 spots among the 61 analyzed were identified. Functional classification showed that the main affected categories were “Cell rescue, defense, and virulence” and “Metabolism”; while 20% were found to be storage proteins with the rest related to minor categories. Activity of antioxidant enzymes was also evaluated. The most conspicuous change was an increase in superoxide dismutase in both the flavedo and juice sacs. Peroxidases increased in flavedo but decreased in sacs while alcohol dehydrogenase increased in treated flavedo, but not in sacs. Other fermentative enzymes were not affected. Metabolite content showed a higher concentration of sugars in heat treated fruit, while the main acids were slightly or not affected. These results are consistent with the development of a lower degree of fruit susceptibility to fungal pathogens, thus explaining the maintenance of postharvest quality.  相似文献   
973.
A protozoological survey was performed on waste stabilization lagoons to isolate, identify, and determine the incidence of zooflagellates present in these waters. A correlation between the species found and the physicochemical parameters determined was also done. Fifteen samplings were analyzed from June 1981 to April 1982. Free-living zooflagellates included: Bodo edax Klebs: Bodo caudatus Dujardin;Trepomonas agilis Dujardin;Pleuromonas jaculans Perty (all of them polisaprobic indicators);Bodo saltans Ehrenberg (a mesosaprobic indicator); and Bodomorpha minima Hollande. A human commensal species Enteromonas hominis Da — Fonseca, was also isolated. The performance of the lagoons was predominantly anaerobic. The temperature seemed to be the most influential factor on the incidence of the zooflagellates isolated, especially in winter time.  相似文献   
974.
The aim of the present study was to evaluate the effects of the application of wood-bark ash (WBA) on the growth and nutritional status of a 5-year-old hybrid chestnut plantation in two consecutive periods of 3 and 4 years, i.e., from age 5 to 8 years and from age 8 to 12 years, respectively. A field experiment, which included 3 treatments and 4 replicate blocks, was established on an acidic, organic matter-rich mineral soil. The treatments were two different doses of ash (10 and 20 t ha?1) and an unfertilized control. Application of the ash (by spreading on the ground) produced mean increases of 16% in diameter and 11% in height growth of trees during the first 3 years, considering both doses together; the response was also significant for the subsequent period, particularly with the higher dose of ash (increases of 11% in diameter and 15% in height growth). The ash had a marked effect, although clearly short lived, on pH (H2O) levels (an increase of 0.6 units) and on exchangeable soil K, Ca and Mg. The nutritional status of the plantation was improved, mainly in terms of K, Ca and Mg, and the results of a vector analysis indicated that these elements, particularly K, were limiting forest production. Foliar or soil nutrient concentrations in the mineral soil were no longer affected by the ash at age 12 years. We recommend the application of two doses of 10 Mg ha?1 throughout the rotation for fertilizing acid mineral soils that are rich in organic matter.  相似文献   
975.
Journal of Plant Diseases and Protection - Pepino mosaic virus (PepMV) disease causes important losses in tomato (Solanum lycopersicum) yield around the world. In order to find new sources of...  相似文献   
976.
In this study, oil bodies (OBs) from Gevuina avellana (OBs-G) and Madia sativa (OBs-M) were isolated and characterized. Microscopic inspection revealed that the monolayer on OB-G was thinner compared to that on OB-M. Cytometric profiles regarding size, complexity, and staining for the two OB sources were similar. Fatty acid to protein mass ratio in both OBs was near 29, indicating high lipid enrichment. OBs-G and OBs-M showed a strong electrostatic repulsion over wide ranges of pH (5.5-9.5) and NaCl concentration (0-150 mM). Proteins displaying highly conserved sequences (steroleosins and aquaporins) in the plant kingdom were identified. The presence of oleosins was immunologically revealed using antibodies raised against Arabidopsis thaliana oleosins. OBs-G and OBs-M exhibited no significant cytotoxicity against the cells. This is the first report about the isolation and characterization of OBs-G and OBs-M, and this knowledge could be used for novel applications of these raw materials.  相似文献   
977.
Land-use intensification causes species losses reducing phylogenetic and functional trait diversity as well as ecosystem function. Phylogenetic (PD) and functional (FD) diversity of regional assemblages have been identified as a key to understanding ecosystem and community functioning, yet it has been rarely included in conservation planning. The use of indicator groups to represent species richness is by far the most common measure used for developing plans to conserve current and future biodiversity. Could indicator groups be used for representing PD and FD of whole assemblages? Using a continuous measure of PD and FD derived from phylogenies and quantitative functional traits of species and their functional relationships, we assessed the effectiveness of 16 indicator groups in representing these evolutionary and functional components of biodiversity to answer this question. We focused our analyses on the entire set of 854 bird species occurring in the Atlantic Forest Biodiversity Hotspot, as a case study. We show that a particular bird order (Apodiformes) is the most effective surrogate group to capture PD, while the Charadriiformes and restricted-range species are the most effective surrogate group to capture FD. Their use as a shortcut to conservation planning is likely to guarantee the conservation of evolutionary and ecosystem processes through the representation of the unique species, as well as ecosystem stability in the long term, with the representation of the redundant species.  相似文献   
978.
979.
A 5-year-old Mangalarga mare was referred to the Veterinary Teaching Hospital of the Veterinary Medical School in Botucatu with a complaint of a persistent 2-month ovarian follicle which had grown progressively to 20 cm in diameter. Ultrasonography showed a circular, cystic structure in the right ovary, whose wall was thickened and interior was filled with anechoic content. Ovarian neoplasia was suspected, and a unilateral ovariectomy was performed through the paralumbar fossa, using general anesthesia through inhalation. Histopathological evaluation concluded that the ovarian enlargement was caused by a fibrothecoma. The present report describes features of fibrothecoma, which is extremely rare in the equine species.  相似文献   
980.
We studied the effect of 1,2-bis-(o-aminophenoxy)-ethane-N,N,N′,N′-tetraacetic acid, tetraacetoxymethyl ester (BAPTA-AM) on the outcome of cryopreservation of stallion spermatozoa and whether reextension of thawed sperm in a more physiological and Ca2+-containing medium might improve the characteristics of thawed stallion spermatozoa. Individual ejaculates from six stallions were collected and split into three subsamples. The first two samples were supplemented with the membrane-permeable Ca2+ chelator BAPTA-AM at final concentrations of 5 and 10 μM, respectively, while the third subsample served as control. After 4 weeks of storage, samples were thawed in a water bath at 37°C and evaluated using flow cytometry and computer-assisted sperm analysis (CASA). In a second experiment, in order to determine whether restoring Ca2+ could improve sperm quality after cryopreservation, thawed semen was washed by centrifugation and resuspended in Tyrode's complete medium. BAPTA-AM supplementation did not modify the outcome of cryopreservation; however, changing the spermatozoa from INRA 96 to Tyrode's complete medium resulted in significant improvements in the percentages of live sperm and total motility post thaw.  相似文献   
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