1,720,955 research outputs found
Microencapsulated sodium butyrate as an alternative antimicrobial additive in broiler diets challenged with Eimeria spp on intestinal integrity
No full textAlega-se que o uso de antibióticos como promotores de crescimento está relacionado com a resistência microbiana, o que tem preocupado nutricionistas e impulsionado os estudos que avaliam o butirato de sódio microencapsulado (BSM) com a finalidade de melhorar as condições no trato gastrintestinal. Diante disso, um estudo foi conduzido com o objetivo de avaliar o efeito do BSM sobre o desempenho, morfometria intestinal, contagem de oocistos das excretas (OOPG), escore de lesão do intestino delgado e turnover do carbono da mucosa intestinal de frangos de corte desafiados com Eimeria spp. 1.200 pintos de corte machos, Ross, foram distribuídos em um delineamento inteiramente casualizado, com cinco tratamentos e seis repetições. Os tratamentos consistiram de: T1- controle negativo, ração basal (RB); T2- RB + 1.000 mg/kg (0,10%) de BSM; T3- RB + 1.500 mg/kg (0,15%) de BSM; T4- RB + 2.000 mg/kg (0,20%) de BSM; T5- controle positivo, RB + antibiótico. Não foram observadas diferenças estatísticas para as variáveis de desempenho e morfometria intestinal de 1 a 42 dias. Porém, notou-se que as inclusões superiores de BSM (1.500 e 2.000 mg/kg) mostraram ter potencial ao apresentar maiores valores no ganho de peso (GP), consumo de ração (CR), viabilidade (VB) e fator de produção (FP), além de melhor conversão alimentar (CA) e maior altura das vilosidades, quando comparado aos demais níveis de inclusão e à adição de antibiótico. Na contagem de oocistos e análise de escore de lesão, observou-se diferença apenas para períodos de coleta, em que maior excreção detectou-se aos 7 dias pós-inoculação. As lesões causadas por E. acervulina e E. tenella atenuaram-se a partir do 10o e 8o dia pós-inoculação, respectivamente, e as maiores lesões provocadas pela E. maxima observaram-se 5 dias após a inoculação. No período de 0 a 21 dias, os tratamentos que receberam aditivos (BSM ou antibiótico) apresentaram menores valores de meia-vida, acelerando o turnover do carbono da mucosa intestinal. No período de 22-42 dias os tratamentos com inclusão de 0,15% e 0,20% de BSM, e o tratamento com antibióticos apresentaram os maiores valores de meia-vida 35,29h; 32,92h e 38,27h respectivamente, indicando que o BSM conseguiu proteger a mucosa intestinal dos danos causados pelas Eimerias. Conclui-se que o uso de BSM na dieta não interfere no desempenho de frangos de corte, porém assemelha-se ao antibiótico na preservação da mucosa intestinal pós-desafio com Eimeria spp.It is alleged that the use of antibiotics as growth promoters are related to microbial resistance, which has concern nutritionists and propels studies that evaluating microencapsulated sodium butyrate (MSB), for the purpose of improving the conditions of gastrointestinal tract. With the aim of evaluating the effect of MSB on performance, intestinal morphometry, count of oocysts excreted per gram of feces and intestinal mucosa carbon turnover of broilers challenged with Eimeria spp. 1.200 1-d-old male, Ross, allotted in a completely randomized design with 5 treatments and 6 replications. Treatments consisted of: T1 – Negative control, basal diet (BD); T2 - BD + 1,000 mg/kg (0.10%) of microencapsulated sodium butyrate (MSB); T3 -BD + 1,500 mg/kg (0.15 %) of MSB; T4 - BD + 2,000 mg/kg (0.20%) of MSB; T5 – Positive control, BD + antibiotic. No statistical differences were observed between the treatments for the variables of performance and intestinal morphometry in the studied periods. Therefore, it was noted that higher inclusions of MSB (1,500 and 2,000 mg/kg) showed to have potential when presenting higher values in average gain (AG), average feed intake (AFI), viability (VB), and production factor (PF), besides better feed conversion (F:G) and higher villus height, when compared to other levels of inclusion and the addition of antibiotics. In the oocyst count and lesion score analysis, it was observed statistical differences only for the studied collection periods, in which higher excretion was detected at 7 days after inoculation. The lesions caused per E. acervulina and E. tenella attenuated from the 10- and 8-day post-inoculation, respectively, and the major injuries caused per E. maxima were observed 5 days after inoculation. In the period of 0-21 days, the treatments that received additives (MSB or antibiotic) presented lower half-lives values, accelerating the turnover of the intestinal mucosa. In the period of 22-42 days, the treatments with the inclusion of 0.15% and 0.20% of MSB, and the treatment with antibiotics presented the highest half-lives values 35.29h, 32.92h and 38.27h, respectively. indicating that MSB was able to protect the intestinal mucosa from damage caused by Eimerias. It is concluded that the use of MSB in the diet doesn’t interfere in the performance of broilers, however, resembles the antibiotic in the maintenance of post-challenge intestinal mucosa with Eimeria spp.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)2018/10672-02018/21792-
Pequi oil (Caryocar brasiliense Camb.) in the diet of broilers subjected to heat stress: a nutritional and proteomic approach
No full textO presente estudo foi conduzido com o objetivo de avaliar o efeito da inclusão do óleo de pequi (OP) em dietas para frangos de corte submetidos ao estresse cíclico pelo calor sobre o desempenho, peso relativo e comprimento dos órgãos, atividade de enzimas antioxidantes do fígado, morfometria intestinal e o perfil diferencial de proteínas expressas no tecido hepático por meio do método shotgun LC-MS/MS. Foram alojados 216 pintos de corte, machos, com um dia de idade, da linhagem Cobb® 500, distribuídos em delineamento inteiramente casualizado, em esquema fatorial 2×2, sendo duas câmeras climáticas: termoneutra (TN) e estresse cíclico pelo calor (EC); e duas dietas: Controle (CT) e CT + 0,60% de inclusão do óleo de pequi (OP), com nove repetições de seis aves cada, totalizando quatro tratamentos. As aves e as rações experimentais foram pesadas semanalmente para avaliação do desempenho zootécnico. Aos 42 dias de idade, uma ave por repetição foi sacrificada para a coleta de órgãos, amostras de intestino (duodeno e jejuno) e tecido hepático, para a realização das análises laboratoriais. Não foram observadas interações significativas entre temperatura e dieta para as variáveis de desempenho, peso relativo dos órgãos, atividade hepática das enzimas antioxidantes e morfometria intestinal (P>0,05), porém foram observadas interações significativas para a variável contagem de células caliciformes (CC) no duodeno. No período de 1 a 21 dias de idade, frangos alimentados com OP apresentaram maior peso final (PF) e ganho de peso (GP) em comparação com os frangos do CT. No período de 1-42 dias, os frangos mantidos em EC apresentaram menor PF, GP e consumo de ração (CR), conversão alimentar (CA) e fator de eficiência produtiva (FEP), e os frangos que receberam OP apresentaram maior PF e GP em comparação aos alimentados com dieta CT. Frangos mantidos em EC apresentaram menor peso relativo do fígado e do intestino delgado, e menor largura da base da vilosidade (LB) no duodeno, e os frangos do tratamento OP apresentaram menor peso relativo do fígado e maior LB no duodeno. Foi observada maior atividade hepática das enzimas SOD e GPx em frangos submetidos ao EC. Na análise do perfil de proteínas expressas, foram encontradas um total de 668 proteínas no proteoma do fígado de frangos de corte alimentados com 0,60% de OP. Estas proteínas estão associadas ao metabolismo celular, metabolismo de proteínas e lipídios, sistema antioxidante, e choque térmico. Conclui-se que o OP demonstra ser um aditivo promissor na melhora do desempenho de frangos de corte, promovendo alterações positivas na morfometria duodenal, além de ser eficaz para diminuir os efeitos deletérios causados pelo estresse pelo calor. O EC foi capaz de induzir o estresse oxidativo, causando efeitos negativos sobre o desempenho e disfunção hepática em frangos de corte.The aim of this study was to evaluate the effect of including pequi oil (PO) in diets for broilers subjected to cyclic heat stress on performance, relative weight and length of organs, analysis of antioxidant enzyme activity in the liver, intestinal morphometry and the differential profile of proteins expressed in liver tissue using the LC-MS/MS shotgun strategy. A total of 216 one-day-old male Cobb® 500 broiler chicks were housed in a completely randomized design (CRD), in a 2×2 factorial scheme, with two climatic chambers: thermoneutral (TN) and cyclic heat stress (HS); and two diets: Control (CT) and CT + 0.60% inclusion of pequi oil (OP), with nine replicates of six birds each, making a total of four treatments. The birds and the experimental rations were weighed weekly to obtain the performance. At 42 days-old, one bird per repetition was sacrificed to collect organs, samples of intestine (duodenum and jejunum) and liver tissue for laboratory analysis. There were no significant interactions between temperature and diet for the variables of performance, relative organ weight and hepatic activity of antioxidant enzymes and intestinal morphometry (P>0.05). However, there were significant interactions for the variable goblet cell count (CC) in the duodenum. In the period from 1 to 21 days, broilers fed OP had a higher body weight (BW) and body weight gain (BWG) compared to broilers fed CT. In the period from 1-42 days, the birds kept on HS had lower BW, BWG and average feed intake (AFI) feed conversion ratio (FCR) and productive efficiency factor (PEF), and the broilers given OP had higher BW and BWG compared to those fed the CT diet. Birds kept in HS had lower relative liver and small intestine weights and lower villus base width (WV) in the duodenum, while OP chickens had lower relative liver weights and higher WV in the duodenum. Higher hepatic activity of the enzymes SOD and GPx was observed in broilers subjected to HS. In the analysis of the expressed protein profile, a total of 668 proteins were found in the liver proteome of broilers fed 0.60% OP. These proteins are associated with cell metabolism, protein and lipid metabolism, the antioxidant system and heat shock. It is concluded that OP is a promising additive for improving broiler performance, promoting positive changes in duodenal morphometry, as well as being effective in reducing the deleterious effects caused by heat stress. CE was able to induce oxidative stress, causing negative effects on performance and liver dysfunction in broilers.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESP: 2022/12698-1Capes: 00
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
