428 research outputs found
Comparison of nonlinear growth models and factors affecting body weight at different ages in Toy Poodles
Limited information is available to evaluate optimal growth in Toy Poodles. This work aimed at comparing three growth curves, proposing centile charts and developing a model to estimate the adult body weight (BW) in Toy Poodles. A total of 65 puppies (male = 30, female = 35) born in the same breeding centre were used. BW at birth and, weekly BW, for 53 weeks, BW of parents, litter size, type of management, daily activity and neutering were recorded. Forty-six puppies were sold, and their data were reported by the new owners. Three growth curves (i.e. Hawthorne, Brody and Gompertz) were constructed and compared; Linear Mixed Models including demographic characteristics and management habits were built. The BW at birth was 154 \ub1 35 g and adult BW was 3208 \ub1 860 g. Based on the goodness-of-fit and accuracy indices, Gompertz was the best growth model and was selected to plot centile curves based on sex. Toy Poodles achieved 50% of their adult weight at 11\u201312 weeks, with an overall growth rate of 11.8%. Adult BW was affected by birth BW (p <.01), sex (p <.05) and mother\u2019s BW (p <.01) and their effects varied depending on the age. Extrinsic factors, including litter size, type of management and daily activity were less significant, probably due to the standardised and high-level management of these Toy Poodles. These new and applicable tools for monitoring the growth and predicting adult BW could be useful for veterinarians, breeders and owners for early diagnosis of poor health and welfare. Subject classification codes: companion animals sectionsHighlights Performance of three logistic models for describing the growth curve in Italian Toy Poodles were compared Based on the goodness of fit and accuracy indices, Gompertz was the best growth model The centile growth curves were constructed for males and females using the Gompertz Adult body weight (BW) was mainly affected by the sex and birth BW, and less by BW of the parents and litter size Monitoring BW of puppies may be useful to enhance their health and welfare
Hibridização genômica in situ em triticeae: um enfoque metodológico.
bitstream/CNPT-2010/40760/1/p-co270.pd
Ex vitro hairy root induction in detached peanut leaves for plant-nematode interaction studies.
Abstract Background Peanut (Arachis hypogaea) production is largely affected by a variety of abiotic and biotic stresses, including the root-knot nematode (RKN) Meloidogyne arenaria that causes yield losses worldwide. Transcriptome studies of wild Arachis species, which harbor resistance to a number of pests and diseases, disclosed several candidate genes for M. arenaria resistance. Peanut is recalcitrant to genetic transformation, so the use of Agrobacterium rhizogenes-derived hairy roots emerged as an alternative for in-root functional characterization of these candidate genes. Results The present report describes an ex vitro methodology for hairy root induction in detached leaves based on the well-known ability of peanut to produce roots spontaneously from its petiole, which can be maintained for extended periods under high-humidity conditions. Thirty days after infection with the A. rhizogenes ‘K599’ strain, 90% of the detached leaves developed transgenic hairy roots with 5 cm of length in average, which were then inoculated with M. arenaria. For improved results, plant transformation, and nematode inoculation parameters were adjusted, such as bacterial cell density and growth stage; moist chamber conditions and nematode inoculum concentration. Using this methodology, a candidate gene for nematode resistance, AdEXLB8, was successfully overexpressed in hairy roots of the nematode-susceptible peanut cultivar ‘Runner’, resulting in 98% reduction in the number of galls and egg masses compared to the control, 60 days after M. arenaria infection. Conclusions This methodology proved to be more practical and cost-effective for functional validation of peanut candidate genes than in vitro and composite plant approaches, as it requires less space, reduces analysis costs and displays high transformation efficiency. The reduction in the number of RKN galls and egg masses in peanut hairy roots overexpressing AdEXLB8 corroborated the use of this strategy for functional characterization of root expressing candidate genes. This approach could be applicable not only for peanut–nematode interaction studies but also to other peanut root diseases, such as those caused by fungi and bacteria, being also potentially extended to other crop species displaying similar petiole-rooting competence
Self-Healing Concrete: Concepts, Energy Saving and Sustainability
The production of cement accounts for 5 to 7% of carbon dioxide emissions in the world, and its broad-scale use contributes to climate imbalance. As a solution, biotechnology enables the cultivation of bacteria and fungi for the synthesis of calcium carbonate as one of the main constituents of cement. Through biomineralization, which is the initial driving force for the synthesis of compounds compatible with concrete, and crystallization, these compounds can be delivered to cracks in concrete. Microencapsulation is a method that serves as a clock to determine when crystallization is needed, which is assisted by control factors such as pH and aeration. The present review addresses possibilities of working with bioconcrete, describing the composition of Portland cement, analysis methods, deterioration, as well as environmental and energetic benefits of using such an alternative material. A discussion on carbon credits is also offered. The contents of this paper could strengthen the prospects for the use of self-healing concrete as a way to meet the high demand for concrete, contributing to the building of a sustainable society
Genetic parameters and selection of sugarcane in early selection stages for resistance to sugarcane borer Diatraea saccharalis.
A T1 (sugarcane population originating from true seeds) and T2 (first sugarcane clonal stage) population were used to estimate genetic parameters and compare selection strategies for Diatraea saccharalis (Lepidoptera: Crambidae) resistance in sugarcane. In the T1 stage, heritability at the family mean level (h²=0.77) was higher than individual genotype heritability (h²=0.16), and the additive genetic effect was more important for sugarcane borer resistance than non-additive effects. In addition, there was high genotypic variance among and within full-sib families. In the T2 population, genotypic variance was high, and heritability at the clone mean level was moderate (h²=0.61). We can conclude that family experiments enable selection of more promising families and parents for borer resistance. However, due to high genotypic variance within families, family selection at the T1 stage must be followed by clone selection at the T2 stage
Prospecção de Cratylia argentea (Desv.) Kuntze nos Estados de Maranhão e Goiás.
Cratylia argentea é um arbusto nativo do Cerrado, de múltiplo uso. Trata-se de uma espécie com potencial para ser utilizada em unidades de produção familiar. Neste Contexto, este trabalho de prospecção, em 2016, objetivou identificar e coletar seus acessos nos estados do Maranhão e Goiás. Os locais de coleta (19 acessos em 13 municípios) foram determinados através dos registros do INCT/Herbário Virtual de Flora e Fungos. Na comunidade Quilombola Kalunga, foram registradas leguminosas nativas de porte arbustivo nas bordas de matas, dentro das matas e nos sistemas tradicionais de produção de milho e arroz. Pelo relato da comunidade do Parque Estadual Terra Ronca, a florada, as ramas, as vagens e as folhas caídas são alimento para o gado na estiagem. Sua frequente presença na beira das estradas, onde ocorreu a maioria das coletas de sementes, reafirma uma das principais características da espécie: a rusticidade. A conservação de C. argentea em seu ambiente natural pode ser ampliada desde que haja a convergência do conhecimento tradicional com o acadêmico, criando estratégias que considerem os saberes e as práticas das comunidades tradicionais e a ecologia da espécie.Edição dos anais do VI Congresso Latino-Americano de Agroecologia, Brasília, DF, 2017
The genome structure of Arachis hypogaea (Linnaeus, 1753) and an induced Arachis allotetraploid revealed by molecular cytogenetics.
Peanut, Arachis hypogaea (Linnaeus, 1753) is an allotetraploid cultivated plant with two subgenomes derived from the hybridization between two diploid wild species, A. duranensis (Krapovickas &amp; W. C. Gregory, 1994) and A. ipaensis (Krapovickas &amp; W. C. Gregory, 1994), followed by spontaneous chromosomal duplication. To understand genome changes following polyploidy, the chromosomes of A. hypogaea, IpaDur1, an induced allotetraploid (A. ipaensis × A. duranensis)4x and the diploid progenitor species were cytogenetically compared. The karyotypes of the allotetraploids share the number and general morphology of chromosomes; DAPI+ bands pattern and number of 5S rDNA loci. However, one 5S rDNA locus presents a heteromorphic FISH signal in both allotetraploids, relative to corresponding progenitor. Whilst for A. hypogaea the number of 45S rDNA loci was equivalent to the sum of those present in the diploid species, in IpaDur1, two loci have not been detected. Overall distribution of repetitive DNA sequences was similar in both allotetraploids, although A. hypogaea had additional CMA3+ bands and few slight differences in the LTR-retrotransposons distribution compared to IpaDur1. GISH showed that the chromosomes of both allotetraploids had preferential hybridization to their corresponding diploid genomes. Nevertheless, at least one pair of IpaDur1 chromosomes had a clear mosaic hybridization pattern indicating recombination between the subgenomes, clear evidence that the genome of IpaDur1 shows some instability comparing to the genome of A. hypogaea that shows no mosaic of subgenomes, although both allotetraploids derive from the same progenitor species. For some reasons, the chromosome structure of A. hypogaea is inherently more stable, or, it has been at least, partially stabilized through genetic changes and selection
Transcriptome analysis in response to gradual water deficit in Arachis wild relatives.
Peanut (cultivated tetraploid Arachis hypogaea) is an important food legume widely cultivated mainly in Asia, Africa and the Americas although its productivity is limited in drought-prone areas; therefore the development of drought-resistant varieties is a priority. Peanut has a narrow genetic diversity and is reproductively isolated from its wild diploid relatives due to ploidy differences. In contrast to peanut, wild relatives have higher genetic diversity and show adaptation to a range of environments thus constituting a rich source of allele diversity for resistance to biotic and tolerance to abiotic stresses. In this study, the transcriptomes of two wild diploids, A. duranensis and A. magna, representatives of the AA and BB peanut component genomes respectively, were analyzed under gradual water deficit. Two SSH libraries produced from roots of A. magna generated 759 Sanger ESTs with 249 Unigenes, whilst from A. duranensis roots, 380,601 Roche/454 reads resulted in12,792 Unigenes. Forty-six Unigenes were selected as drought-related candidates for validation by RT-qPCR by in silico analysis of all libraries. A total of 18 candidate genes showed significantly different levels of expression in stressed plants, confirming their involvement in drought response. To date, this is the first report on global gene expression profile of wild Arachis species submitted to an abiotic stress. Data produced in this study is a valuable resource for gene identification, characterization of new alleles and development of molecular markers in Arachis
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