Efeitos da substituição parcial do farelo de algodão para ovinos em confinamento: análise econômica

The objective of this study was to make an economic analysis of the results of partial replacement of cotton seed meal by Christinas bush ("mata-pasto") hay on sheep production in confinement at 0%, 5%, 10% and 15% levels. Costs, income and gross return were analysed. The results showed that all systems had a negative return. The best gross return was obtained when the Christinas bush has replaced the cotton seed meal in 5%.O objetivo deste estudo foi o de fazer uma análise econômica dos resultados da substituição parcial do farelo de algodão por feno de mata-pasto classificados a níveis de 0%, 5%, 10% e 15%, para ovinos em confinamento. Foram analisados os custos, receitas e margens de renda bruta. Os resultados mostraram que todos os sistemas tiveram margens de renda bruta negativas. A melhor margem foi obtida quando se substituiu o farelo de algodão por feno de mata-pasto em nível de 5%

Valor nutritivo do farelo de coco em ovinos: balanço energético e de nitrogênio.

Com o objetivo de avaliar o valor nutritivo do farelo de coco (Cocus nucifera) foi determinado o balanço energético e o balanço nitrogenado em borregos deslanados alojados em gaiolas metabólicas providas de separadores de fezes e urina recebendo feno de tifton-85 e níveis crescentes de farelo de coco nos níveis de zero, oito, 17 e 25% de farelo de coco com base na matéria natural, em um esquema inteiramente ao acaso com quatro tratamentos (nível de farelo de coco) e seis repetições (borregos) por tratamento perfazendo um total de 24 observações, empregando o método SNK a 5% de probabilidade para comparação das médias. Não houve efeito do nível de inclusão do farelo de coco sobre consumo e balanço de energia e sobre o consumo e balanço de nitrogênio, todos os níveis de inclusão dem farelo de coco tiveram balanço energético positivo no caso do balanço de nitrogênio todas as dietas tiveram balanço positivo com excessão da dieta com 25% de inclusão de farelo de coco. Concluiu-se que a inclusão de farelo de coco em até 25% teve efeito negativo sobre o consumo de energia, sem alcançar valores que prejudicariam o desempenho dos animais e que 25% de farelo de coco prejudicou o balanço protéico dos animais

Lepidoptera (Insecta) associated with soybean in Argentina, Brazil, Chile and Uruguay.

ABSTRACT:The present research updates the systematic position and nomenclature of Lepidoptera associated with soybean crops in Argentina, Brazil, Chile and Uruguay. Scientific literature lists 69 species of Lepidoptera feeding on soybean plants. These species are representatives of the Superfamilies Noctuoidea (31), Pyraloidea (13), Hesperioidea (12), Tortricoidea (5), Geometroidea (5), and Bombycoidea (3). Diversity of Lepidoptera associated to crop, injury in different parts of the plant, and changes in species composition are discussed considering the changes in plant disease management, introduction of plants expressing Bt proteins, and the recent introduction of Helicoverpa armigera (Hübner) as a new crop pest. RESUMO: The present research updates the systematic position and nomenclature of Lepidoptera associated with soybean crops in Argentina, Brazil, Chile and Uruguay. Scientific literature lists 69 species of Lepidoptera feeding on soybean plants. These species are representatives of the Superfamilies Noctuoidea (31), Pyraloidea (13), Hesperioidea (12), Tortricoidea (5), Geometroidea (5), and Bombycoidea (3). Diversity of Lepidoptera associated to crop, injury in different parts of the plant, and changes in species composition are discussed considering the changes in plant disease management, introduction of plants expressing Bt proteins, and the recent introduction of Helicoverpa armigera (Hübner) as a new crop pest

Potencial reprodutivo de Spodoptera eridania (Stoll) (Lepidoptera: Noctuidae) em laboratório : efeito de múltiplos casais e do tamanho

Este estudo objetivou avaliar o efeito de confinar três casais em cada gaiola e o tamanho de adultos emergidos de pupas pequenas, medias e grandes (278,67 mg, 333,20 mg e 381,58 mg, respectivamente), sobre o potencial reprodutivo de S. eridania (Stoll, 1782), em condições controladas (25 ± 1 °C, 70% UR e 14 horas de fotofase). Avaliou-se a sobrevivência, o número de cópulas, fecundidade e fertilidade dos adultos. A sobrevivência não diferiu significativamente entre fêmeas provenientes de pupas de diferentes tamanhos, mas os machos oriundos de pupas grandes tiveram sobrevivência significativamente menor que os demais tamanhos. A fecundidade diferiu significativamente e correlacionou-se positivamente com o tamanho. O número de cópulas (espematóforos) e a fertilidade não variaram em função do peso pupal. Os resultados enfatizam a importância de indicar o número de cópulas e o tamanho dos insetos estudados para que comparações entre os parâmetros reprodutivos possam ser efetuadas.This study aimed to evaluate the effect of keeping three couples in the same cage, and the size of adults emerged from small, medium-sized and large pupae (278.67 mg; 333.20 mg and 381.58 mg, respectively), on the reproductive potential of S. eridania (Stoll, 1782) adults, under controlled conditions (25 ± 1 °C, 70% RH and 14 hour photophase). We evaluated the survival, number of copulations, fecundity and fertility of the adult females. The survival of females from these different pupal sizes did not differ statistically, but the survival of males from large pupae was statistically shorter than from small pupae. Fecundity differed significantly and correlated positively with size. The number of effective copulations (espematophores) and fertility did not vary significantly with pupal size. Our results emphasize the importance of indicating the number of copulations and the size of the insects when reproductive parameters are compared

Utility of arsenic-treated bird skins for DNA extraction

Background: Natural history museums receive a rapidly growing number of requests for tissue samples from preserved specimens for DNA-based studies. Traditionally, dried vertebrate specimens were treated with arsenic because of its toxicity and insect-repellent effect. Arsenic has negative effects on in vivo DNA repair enzymes and consequently may inhibit PCR performance. In bird collections, foot pad samples are often requested since the feet were not regularly treated with arsenic and because they are assumed to provide substantial amounts of DNA. However, the actual influence of arsenic on DNA analyses has never been tested. Findings: PCR success of both foot pad and body skin samples was significantly lower in arsenic-treated samples. In general, foot pads performed better than body skin samples. Moreover, PCR success depends on collection date in which younger samples yielded better results. While the addition of arsenic solution to the PCR mixture had a clear negative effect on PCR performance after the threshold of 5.4 μg/μl, such high doses of arsenic are highly unlikely to occur in dried zoological specimens. Conclusions: While lower PCR success in older samples might be due to age effects and/or DNA damage through arsenic treatment, our results show no inhibiting effect on DNA polymerase. We assume that DNA degradation proceeds more rapidly in thin tissue layers with low cell numbers that are susceptible to external abiotic influences. In contrast, in thicker parts of a specimen, such as foot pads, the outermost horny skin may act as an additional barrier. Since foot pads often performed better than body skin samples, the intention to preserve morphologically important structures of a specimen still conflicts with the aim to obtain optimal PCR success. Thus, body skin samples from recently collected specimens should be considered as alternative sources of DNA

Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets