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71.
AW PHILBEY C. BUTTON† AW GESTIER† BE MUNRO§ JRW GLASTONBURY M. HINDMARSH¶ SCJ LOVE# 《Australian veterinary journal》1991,68(7):237-240
Twenty ostrich chicks that died at, or within, 1 week after hatching were examined from 7 farms with poor (43 to 75%) hatchability. All chicks had anasarca and 15 had mild, generalised, acute degenerative changes in the complexus and pelvic limb muscles. One had fibrinoid degeneration of arterioles. Biochemical examinations produced no evidence of deficiencies of selenium, vitamin A or vitamin E. The syndrome was related to high relative humidity during incubation. Malpositioning also was a cause of embryo mortality. 相似文献
72.
Adriana Príncipe Alice Nunes Pedro Pinho Lúcio do Rosário Otília Correia Cristina Branquinho 《European Journal of Forest Research》2014,133(4):757-767
Understanding forest regeneration at sites previously used for agriculture underlies the establishment of science-based woodlands management policies. This is especially relevant in semi-arid areas, where the tree cover is critical in ameliorating the effects of aridity and in preventing desertification and land degradation. Natural regeneration in semi-arid areas occurs very slowly, which in part explains why it has hardly been studied. In the present work, we sought to devise a method to predict the natural regeneration potential of woodlands in semi-arid areas, to be used in guiding restoration efforts. Specifically, we evaluated holm oak coverage at a long-term ecological research site and then designed and validated a model to predict the natural regeneration of holm oak based on a few environmental variables. Unlike available studies, we obtained long-term information on tree regeneration (making use of >60 years of aerial photography) and climate (using long-term climate and microclimate data). We found that microclimate, measured using the potential solar radiation as a proxy, was a key driver of natural regeneration: after 60 years of agricultural abandonment, less sun-exposed areas attained a tree cover >90 %, whereas in more sun-exposed areas it remained below 20 %. We then used the model to map the natural regeneration potential, first in the study area and then in an area where holm oak plantations had been unsuccessfully introduced. In the latter case, the model successfully predicted the failure of this reforestation effort. Our results support the use of this model by decision makers to optimize management practices, as it will encourage the concentration of efforts in areas more prone to successful reforestation and allow the identification of areas more likely to benefit from natural regeneration processes. 相似文献
73.
Canada N Meireles CS Ferreira P Correia da Costa JM Rocha A 《Veterinary parasitology》2006,139(1-3):109-114
Neosporosis is a major cause of abortion in cattle all over the world. Congenital transmission as well as horizontal transmission by ingestion of oocysts has been described. The detection of Neospora caninum DNA in bull semen warrants the investigation of possible transmission through the use of contaminated semen. In this experiment four cows were artificially inseminated with frozen-thawed semen contaminated in vitro with viable N. caninum tachyzoites (group A) and four control cows were inseminated with tachyzoites-free frozen-thawed semen, from the same bull (group B). Serum samples were collected 15 days before the artificial insemination (AI) and at days 10, 14, 21, 28, 45, 60 and 75 post-insemination. All sera samples were tested for neosporosis by direct agglutination test (DAT). Three of the cows from group A had negative DAT titers (< or =1:20) in all of the samples, while the fourth cow from this group had a low titer of antibodies (1:80) at day 10, and became negative at day 45, suggesting a stimulation of the immune system by the tachyzoites placed in uterus, rather than the induction of an infection. All of the cows from group B had negative DAT titers (< or =1:20) in all of the samples. These results suggest that transmission of neosporosis by artificial insemination with frozen-thawed semen is an unlikely event. 相似文献
74.
Guilherme Gomes Verocai Lauro Nogueira Lopes Leonardo Burlini Thaís Ribeiro Correia Clarissa Pimentel de Souza Katherina Coumendouros 《Tropical animal health and production》2009,41(7):1241-1242
This paper reports the occurrence of parasitism by the Oriental eye-fluke, Philophthalmus gralli in ostriches reared in a commercial flock from the State of Minas Gerais State, Southeastern Brazil. The two affected birds
presented lacrimation, inflammatory reaction and loss of body condition. After physical examination the birds revealed, 17
and 15 trematodes each, only in the right eyes. The economic impact of this parasite on Brazilian ostrich industry is still
undetermined, requiring further studies. 相似文献
75.
Furuncular Myiasis Caused by the Human Botfly,Dermatobia hominis,in the Domestic Rabbit: Case Report
G.G. Verocai J.I. Fernandes F.A. Ribeiro R.M.P.S. Melo T.R. Correia F.B. Scott 《Journal of Exotic Pet Medicine》2009,18(2):153-155
The human botfly, Dermatobia hominis (Linnaeus Jr., 1781) (Diptera: Cuterebridae), is geographically found throughout Neotropical America, is considered the major causal agent of furuncular myiasis. This parasite generates considerable damage in affected livestock. Its low host specificity leads to reports of parasitism in several domestic species. The goal of the present study is to report a case of natural infestation by the human botfly (D. hominis) in the domestic rabbit (Oryctolagus cuniculus). 相似文献
76.
Sequential in vitro pepsin digestion of uncooked and cooked sorghum and maize samples 总被引:4,自引:0,他引:4
Nunes A Correia I Barros A Delgadillo I 《Journal of agricultural and food chemistry》2004,52(7):2052-2058
An in vitro protein digestion study, using pepsin, was carried out in uncooked and cooked sorghum and maize flour samples. The digestibility values from the uncooked samples showed that sorghum presents digestibility values similar to those of maize. In the case of the cooked samples, it was found that a wet cooking procedure promotes a decrease in sorghum protein digestibility when compared to maize. Electrophoresis was used to follow the in vitro pepsin sequential digestion procedure, and infrared spectroscopy was applied to establish its efficiency. SDS-PAGE results showed that both uncooked samples (sorghum and maize) behave in a similar way. The wet cooking procedure increases the amount of high molecular weight aggregates and promotes the appearance of two nonreducible and nondigestible 45 and 47 kDa proteins. These two protein fractions are directly related to the loss of digestibility. It was also shown that in cooked sorghum the monomers (gamma-, alpha-, and beta-) are more resistant to digestion than the corresponding uncooked samples. 相似文献
77.
金龟子绿僵菌分生孢子暴露在B段紫外光下毒力的降低 总被引:1,自引:0,他引:1
José C Barbosa 《安徽农业大学学报》2008,35(2):246-249
The UV-A and UV-B wavelengths of solar radiation may seriously reduce viability of Metarhizium anisopliae conidia,a fungus used extensively in Brazil for insect pest control.The conidial tolerances to UV-A and UV-B radiation were studied for one isolate(IBCB 425) commercially available product produced on rice grains.Aqueous or oil emulsion conidial suspensions were irradiated for 0(control),2,or 3 h using the solar simulator filtered with diacetate filter to remove UV-C radiation which afforded 652 mW·m-2 in the spectral range of 280~370 nm.The UV tolerance was based on conidial germination(viability) and virulence to Diatraea saccharalis larvae.Conidia formulated with oil emulsion had higher survival after 3 h of UV exposure,but the virulence of the conidia previously exposed to 2 h of UV radiation were similar when oil formulated or not.The mortality of D.saccharalis caterpillars exposed to non-UV-irradiated conidia was greater than that of larvae exposed to irradiated conidia,and the LT50 values were lower for the non-irradiated suspensions than for those irradiated.This apparent reduction in virulence was directly related reduction in viability or delay of germination of UV-irradiated conidia. 相似文献
78.
Grazziotin AL Santos AP Guimaraes AM Mohamed A Cubas ZS de Oliveira MJ dos Santos LC de Moraes W Vieira RF Donatti L de Barros Filho IR Biondo AW Messick JB 《Veterinary microbiology》2011,152(3-4):415-419
Hemotrophic mycoplasmas (hemoplasmas) are bacteria that attach to red blood cells of mammals, leading to acute and/or subclinical disease in infected animals. It has been suggested that Mycoplasma ovis, a hemoplasma that infects sheep and goats worldwide, may also infect deer. The aim of this study was to evaluate whether South American deer are infected with M. ovis. EDTA-anticoagulated blood samples from a herd of 32 captive South American deer were collected. DNA extraction of blood samples was performed followed by PCR amplification of the 16S and 23S rRNA genes, and sequencing of products. Using M. ovis PCR, 27/31 (87%) were positive, including 21/22 Mazama nana; 2/3 Mazama americana and 4/6 Blastocerus dichotomus. Sequencing of the nearly entire 16S rRNA gene of 26/27 positive samples showed 98.2-98.8% identity to M. ovis of sheep (GenBank, AF338268) and 98.6-99.4% identity to M. ovis-like of a fawn (FJ824847); the 23S rRNA gene from one of these isolates and the fawn's had 97.6% identity. The remaining isolate had just 94.9% identity to the 16S rRNA gene of M. ovis and only 89.4% identity to the 23S rRNA gene of the fawn's M. ovis. This is the first report of M. ovis in captive South American deer, revealing a high prevalence of hemoplasma infection in these animals. 相似文献
79.
Martins J Esteves C Simoes T Correia M Delerue-Matos C 《Journal of agricultural and food chemistry》2011,59(13):6847-6855
The present work describes a solid-phase microextraction (SPME) gas chromatography-tandem mass spectrometry (MS/MS) method to quantify 24 pesticides in fortified white wine and fortified red wine. In this study "fortified wine" refers to a wine in which fermentation is arrested before completion by alcohol distillate addition, allowing sugar and alcoholic contents to be higher (around 80-100 g/L total sugars and 19-22% alcohol strength (v/v)). The analytical method showed good linearity, presenting correlation coefficients (R(2)) ≥ 0.989 for all compounds. Limits of detection (LOD) and quantitation (LOQ) in the ranges of 0.05-72.35 and 0.16-219.23 μg/L, respectively, were obtained. LOQs are below the maximum residue levels (MRL) set by European Regulation for grapes. The proposed method was applied to 17 commercial fortified wines. The analyzed pesticides were not detected in the wines tested. 相似文献
80.
Response of five citrus rootstocks to iron deficiency 总被引:1,自引:1,他引:0
Maribela Pestana Pedro José Correia Manuela David Anunciación Abadía Javier Abadía Amarilis de Varennes 《植物养料与土壤学杂志》2011,174(5):837-846
Citrus established in calcareous soils can be affected by iron (Fe)‐deficiency chlorosis which limits yield and the farmers' income. The degree of deficiency depends on the rootstock, but the resistance to Fe chlorosis still requires further investigation. To study physiological parameters of citrus rootstocks that could be used to evaluate resistance to Fe deficiency, plants of Troyer citrange (Citrus sinensis L. Osb. × Poncitrus trifoliata L. Raf.), Carrizo citrange, Volkamer lemon (Citrus volkameriana Ten. & Pasq.), alemow (Citrus macrophylla Wester), and sour orange (Citrus aurantium L.) were grown in nutrient solutions with 0, 5, 10, 15, or 20 μM Fe. For each rootstock, plant height, root and shoot dry weights, and concentration of Fe in the shoots and roots were measured at the end of the experiment. Chlorophyll (CHL) concentration was estimated throughout the experimental period using a portable CHL meter (SPAD‐502) calibrated for each rootstock. At the end of the experiment, CHL fluorescence parameters were measured in each rootstock with a portable fluorimeter. Maximal and variable fluorescence values indicated that the photochemistry of Troyer was more affected by a low concentration of Fe in the nutrient solution than that of other rootstocks. To compare rootstocks, the absolute CHL concentration was converted into relative yield by employing a scaling divisor based on the maximum value of total CHL in plants without Fe‐deficiency symptoms. Exponential models were developed to determine the minimum Fe concentration in nutrient solution required to maintain leaf CHL at 50% of the maximum CHL concentration (IC50). Models were also developed to assess the period of time the rootstocks were able to grow under Fe‐stress conditions before they reached IC50. Volkamer lemon and sour orange needed the lowest Fe concentration (between 4 and 5 μM Fe) to maintain IC50, and Troyer citrange had the highest Fe requirement (14 μM Fe). Citrus macrophylla and Carrizo citrange required 7 and 9 μM of Fe, respectively. Similarly, Volkamer lemon and sour orange rootstocks withstood more days under total Fe depletion or with a low concentration of Fe (5 μM Fe in nutrient solution) until they reached IC50, compared to the other rootstocks. The approach used led to a classification of the rootstocks into three categories, regarding their internal tolerance to Fe chlorosis: resistance (sour orange and Volkamer lemon), intermediate resistance (C. macrophylla and Carrizo citrange), and reduced resistance (Troyer citrange). 相似文献