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Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of...  相似文献   
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The objective of this study was to estimate, through mathematical models, energy and protein requirements for maintenance and gain of hair sheep raised in the tropical region of Brazil. To determine the equation parameters, a meta‐analysis of seven independent experiments of nutrient requirements was performed, comprising a total of 243 experimental units (animals), which were conducted under tropical conditions, using hair sheep in growing and finishing phases and endowed of the following quantitative data for each animal: body weight (BW ), empty body weight (EBW ), average daily gain (ADG ), empty body gain (EBG ), heat production (HP ), metabolizable energy intake (MEI ), retained energy (RE ), metabolizable protein intake (MPI ) and body protein content. The regression equations generated were as follows: for Net Energy for maintenance, (NE m): ; for Net Energy for gain, (NE g): ; for Metabolizable Protein for maintenance,(MP m): MPI (g/day) = 24.8470 (±7.3646) + 560.28 (±99.6582) × EBG (kg/day); for Net Protein for gain, (NP g): . The NE m requirement was 0.246 MJ EBW?0.75 day?1. The metabolizable energy for maintenance requirement was 0.391 MJ EBW?0.75 day?1. Considering an ADG of 100 g, the NE g requirement ranged from 0.496 to 1.701 MJ/day for animals with BW ranging from 10 to 40 kg respectively. The efficiencies of use of the metabolizable energy for maintenance and gain were 0.63 and 0.36 respectively. The MP m requirement was 3.097 g EBW?0.75 day?1. Considering an ADG of 100 g, the NP g requirement ranged from 12.4 to 10.5 g/day for animals with BW ranging from 10 to 40 kg respectively. The total metabolizable energy and protein requirements were lower than those reported by the NRC and AFRC systems. Thus, our results support the hypothesis that nutrient requirements of hair sheep raised in tropical regions differ from wool sheep raised in temperate regions. Therefore, the use of the equations designed in this study is recommended.  相似文献   
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A 4-mo-old northern red-shouldered macaw (Diopsittaca nobilis) was admitted to the veterinary hospital of the Arruda Câmara Zoo, in the State of Paraiba, Brazil, for investigation of an orbital mass. Given rapid progression and lack of response to treatment, the bird was euthanized, and an autopsy was performed. Histologically, the mass consisted of a retrobulbar invasive tumor characterized by tubular and rosette-like structures, with interspersed heteroplastic tissues, such as aggregates of neuroglial cells and islands of hyaline cartilage. The tumor was immunopositive for pancytokeratin, GFAP, NSE, and S100. These findings were compatible with an ocular teratoid medulloepithelioma, a neoplasm best described in humans but also reported rarely in young cockatiels and African Grey parrots.  相似文献   
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From September 1995 to February 2001, blood samples were collected from 865 neotropical felids belonging to 8 different species. These animals were housed in 86 institutions located in 78 cities of 20 Brazilian states. Our goal was to identify the risk factors associated with sero-positivity to Toxoplasma gondii in captive neotropical felids from Brazil. All serum samples were tested by the modified agglutination test (MAT), using formalin-fixed whole tachyzoites and mercaptoethanol. For each animal an individual questionnaire was filled with questions about tattoo number, felid species, age, sex, origin, number of animals in the group, introduction of new animals in the group, time in the institution, eating meat previously frozen for a period <7 days in the last 6 months, eating meat of run-over or euthanized animals in the last 6 months, predation of rodents or birds in the last 6 months and presence of domestic cats near the enclosures in the last 6 months. The total sero-prevalence was 55% (95% CI: 52%, 57%). We estimated a prevalence of 46% (95% CI: 40%, 54%) for jaguarundi (Puma yagouaroundi); 58% (95% CI: 53%, 63%) for ocelot (Leopardus pardalis); 50% (95% CI: 45%, 56%) for oncilla (L. tigrinus); 54% (95% CI: 46%, 62%) for margay (L. wiedii); 12% (95% CI: 4%, 31%) for Pampas-cat (L. colocolo); 83% (95% CI: 65%, 93%) for Geoffroy's-cat (L. geoffroyi); 64% (95% CI: 50%, 68%) for jaguar (Panthera onca) and 48% (95% CI: 42%, 54%) for puma (Puma concolor). Multiple logistic regression was used to evaluate the association between the variables in the questionnaire and sero-positivity to T. gondii. We concluded that the independent risk factors for toxoplasmosis were: age >3 years (OR = 4.75 [2.75; 8.2]), eating meat previously frozen for a period <7 days (OR = 2.23 [1.24; 4.01]), and consumption of animals that were run-over or euthanized (OR = 1.64; [1.14; 2.37]).  相似文献   
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ABSTRACT The secreted phosphatase activities of two trypanosomatid parasites were characterized and compared with supernatants of living cells. The plant parasite Phytomonas fran?ai and the phytophagous hemipteran parasite Herpetomonas sp. hydrolyzed p-nitrophenylphosphate at a rate of 15.54 and 6.51 nmol Pi/mg of protein per min, respectively. Sodium orthovanadate (N(a)VO(3)) and sodium fluoride (NaF) decreased the phosphatase activities. The phosphatase activity of P. fran?ai was drastically diminished (73% inhibition) in the presence of sodium tartrate, whereas the phosphatase activity of Herpetomonas sp. was inhibited by 23%. Cytochemical analysis showed the localization of these enzymes on the external surface and in the flagellar pocket of the two trypanosomatids. Sodium tartrate inhibited this reaction, confirming the biochemical data. Platelet-activating factor modulated the phosphatase activities, inhibiting P. fran?ai activity and stimulating Herpetomonas sp. phosphatase activity.  相似文献   
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A light microscopic examination of the seminiferous epithelium of the pigeon was carried out. Comparisons are made between the spermiogenic stages of the pigeon and that of the domestic fowl and mammals.  相似文献   
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An avian pathogenic Escherichia coli (APEC) strain designated SHS4, isolated from a chicken with clinical signs of swollen head syndrome (SHS), adhered to but did not invade Hep-2 and tracheal epithelial cells. The PCR amplified fimA, csgA and tsh gene sequences. It produced Ia, Ib, E1, E3, K, and B colicins, but not colicin V and aerobactin. It harboured two plasmids of 60 and 98MDa and was resistant to streptomycin and tetracycline. Conjugation with a nalidixic acid (Na) resistant K-12 recipient strain (MS101) showed that the 98MDa plasmid did not transfer, whereas transfer of the 60MDa plasmid resulted in concomitant transfer of adhesion to Hep-2 and tracheal epithelial cells, production of the colicins Ia, E1, E3, and K, and the tsh-related DNA sequence. Transposon (TnphoA) mutagenesis of strain TR4 gave rise to strain Mut23, which lost its adhesive capacities, but was still able to express the same colicins as did strain TR4. PCR was able to amplify the tsh-related DNA sequence in this strain and a molecular probe based on transposon TnphoA indicated that the transposon was inserted in the 60MDa plasmid. Based on these results, we suggest that the 60MDa plasmid have adhesion genes, which may be responsible for the initial colonization of the upper respiratory tract of chickens.  相似文献   
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