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Poorly formulated search strategies can have great influences on the results of a meta-analysis, since it directly impacts the amount and adherence to the theme of the works used for study, therefore, the formulation of a consistent and functional search strategy is essential for the review system to achieve its goals. The objective of this work was to study the impact of different search strategies in a systematic review by performing a meta-analysis to estimate heritability for the mastitis trait in dairy cattle. Once the search strategies were defined, the searches carried out in the Web of science, Scopus, Scielo and Pubmed databases returned 921 studies from which, after going through the identification, selection, eligibility and inclusion processes, 25 studies were selected. Withdrawals from selected articles, 26 heritability estimates were used in the meta-analysis. A random effect model was used, with all analyzes performed by the R program, through the Metafor package. The estimates obtained through the combined statistics of studies for mastitis, presented values of low magnitude (0.05 and 0.06). The effects of search strategies have a significant impact on the meta-analysis estimates produced.

Estratégias de buscas mal formuladas podem apresentar grandes influências nos resultados de uma metanálise, uma vez que impacta diretamente na quantidade e aderência ao tema dos trabalhos utilizados para estudo, portanto, a formulação de uma estratégia de busca consistente e funcional é fundamental para que a revisão sistemática atinja seus objetivos. O objetivo deste trabalho foi estudar o impacto de diferentes estratégias de busca em uma revisão sistemática por meio da realização de uma metanálise para estimação de herdabilidade para a característica mastite em gado de leite. Uma vez definidas as estratégias de busca, as pesquisas realizadas nas bases de dados Web of science, Scopus, Scielo e Pubmed retornaram 921 estudos dos quais, após passarem pelos processos de identificação, seleção, elegibilidade e inclusão, 25 estudos foram selecionados. Retiradas dos artigos selecionados, 26 estimativas de herdabilidades foram utilizadas na realização da metanálise. Utilizou-se um modelo de efeito aleatório, sendo todas as análises realizadas pelo programa R, por meio do pacote Metafor. As estimativas obtidas através da estatística combinada de estudos para mastite, apresentou valores de baixa magnitude (0,05 e 0,06). Os efeitos das estratégias de busca têm impacto significativo nas estimativas de metanálise produzidas.

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The objective of this study was to determine the energy values and metabolizability of different lipid sources in the diet of Japanese quail at the laying phase. The quail were distributed in a completely randomized design with ten replications of seven poultry per treatment, totaling six treatments: basal feed (control) and basal feed containing 10% soybean oil, corn oil, canola oil, sunflower oil, and poultry fat. The values of nitrogen-corrected apparent metabolizable energy (AMEn) and the metabolizability coefficient (MC%) were evaluated. No significant difference was found between the different lipid sources for AMEn (kcal/kg) and MC (%). The value of metabolizable energy corrected for nitrogen for soybean oil was 8,790 kcal/kg; 8,773 kcal/kg for corn oil; 8,784 kcal/kg for canola oil; 8,788 kcal/kg for sunflower oil; and 8,681 kcal/kg for poultry fat in laying Japanese quail. The digestibility coefficients were 93.88% for soybean oil, 93.53% for corn oil, 93.32% for canola oil, 93.74% for sunflower oil, and 93.06% for poultry fat.

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Butyric acid has been studied and utilized intensively in broiler chicken production in order to substitute growth-promoting antibiotics. However, the comprehensive literature on this topic makes it difficult to understand overall results, since there is a noticeable number of studies with conflicting conclusions. Although several research studies have shown that butyric acid may increment broiler chicken's performance, several other studies show the opposite. This work aimed to organize information to understand, through a meta-analysis, whether butyric acid can be used as a performance-enhancing additive for broiler chickens, and whether it can replace growth-promoting antibiotics. It was clear from the results that the effect of butyric acid depends on the microbiological challenge that broilers receive. When broilers are raised without health challenge, butyric acid and even antibiotics do not influence growth performance. However, when broilers are challenged, butyric acid provided an increase in weight gain and a significant improvement in feed conversion, matching the results of antibiotics. We conclude that butyric acid improves broiler performance and can be used to replace growth-promoting antibiotics.(AU)

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The objective of this study was to fully describe the protocol with standardized modifications and evaluate the lysozyme activity, an indicator of innate immunity in tilapia, to compare lipopolysaccharide (LPS) with Streptococcus agalactiae injections. Lysozyme was determined in serum using the turbidimetric method, in which lysozyme activity was evaluated by Micrococcus lysodeikticus lysis, with modifications for microplate assay. The experiment was conducted in a completely randomized design. Juvenile tilapia was divided in the following six treatments: challenged with phosphate buffer PBS (control) and 100, 250, 500, and 600 µg kg−1 LPS and S. agalactiae. All treatments were challenged for 72 h and seven days and then sampled to determine lysozyme activity. After 72 h or seven days, concentrations of LPS promoted changes in lysozyme production, either lesser or equal, depending on concentration when compared with fish injected with S. agalactiae. It was possible to standardize the analysis and determine that the treatment with LPS promotes immunomodulation at a concentration of 250 µg kg−1 LPS, this response being similar to challenge with S. agalactiae.

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A precisão no atendimento das exigências nutricionais é de grande importância na produção de codornas, porém há ausência de consenso quanto às recomendações de proteína bruta (PB) para codornas de linhagens específicas para corte. O presente estudo teve como objetivo determinar a exigência de PB para codornas europeias sobre o desempenho e sobre as características de carcaça. Foi utilizado o delineamento inteiramente casualizado em esquema fatorial 5 × 2, sendo cinco níveis de PB para machos e fêmeas. Na fase inicial (1 a 21dias), foram utilizadas 1.800 codornas e níveis de PB de 20,0, 22,5, 25,0, 27,5 e 30,0%, com seis repetições contendo 30 aves cada. Na fase de crescimento (22 a 45 dias), foram usadas 1.620 codornas e níveis de PB de 17,5, 19,5, 22,0, 24,5 e 27,0%, com seis repetições contendo 27 aves cada. As dietas foram fareladas a base de milho e farelo de soja. O desempenho das codornas foi avaliado ao final de cada período, e o rendimento de carcaça no 45º dia. Aos 21 dias houve maior ganho de peso e melhor conversão alimentar, independentemente do sexo, com 25,50% e 27,06% de PB, respectivamente. No período de 22 a 45 dias, observou-se somente efeito do sexo, sendo que as fêmeas obtiveram desempenho superior. Com relação às características de carcaça, os machos obtiveram maior rendimento de carcaças (quente, fria e dorso); já as fêmeas, apresentaram maior rendimento de cortes (peito, moela e fígado).

Accuracy in meeting nutritional requirements has great importance in quail nutrition however there is a lack of consensus on crude protein (CP) recommendations specific for European quails. The present study aimed to define crude protein requirements for European quails on performance and carcass characteristics. A completely randomized design was used in a 5 × 2 factorial scheme, with five CP levels for male and female quails. In the starting phase (1 to 21 days) it was used 1,800 quails and CP levels were 20,0, 22,5, 25,0, 27,5 and 30,0%, with six replicates containing 30 birds each. In the growth phase (22 to 45 days) it was used 1.620 quails and CP levels were 17,5, 19,5, 22,0, 24,5 and 27,0%, with six replicates containing 27 birds each. Theirs d was a corn soybean based diet in grounded form. The performance of the quails was evaluated in the end of each experimental phase and carcass yield in 45 days. Weight gain and feed conversion ratio was higher for 25,50% and 27,06% respectively, regardless of gender, in 21 days. In the growth phase, it was observed just gender effect in which female quails had higher performance. For carcass characteristics, male quails obtained higher carcass and dorse yield and female quails higher breast, liver and gizzard yields.

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A precisão no atendimento das exigências nutricionais é de grande importância na produção de codornas, porém há ausência de consenso quanto às recomendações de proteína bruta (PB) para codornas de linhagens específicas para corte. O presente estudo teve como objetivo determinar a exigência de PB para codornas europeias sobre o desempenho e sobre as características de carcaça. Foi utilizado o delineamento inteiramente casualizado em esquema fatorial 5 × 2, sendo cinco níveis de PB para machos e fêmeas. Na fase inicial (1 a 21dias), foram utilizadas 1.800 codornas e níveis de PB de 20,0, 22,5, 25,0, 27,5 e 30,0%, com seis repetições contendo 30 aves cada. Na fase de crescimento (22 a 45 dias), foram usadas 1.620 codornas e níveis de PB de 17,5, 19,5, 22,0, 24,5 e 27,0%, com seis repetições contendo 27 aves cada. As dietas foram fareladas a base de milho e farelo de soja. O desempenho das codornas foi avaliado ao final de cada período, e o rendimento de carcaça no 45º dia. Aos 21 dias houve maior ganho de peso e melhor conversão alimentar, independentemente do sexo, com 25,50% e 27,06% de PB, respectivamente. No período de 22 a 45 dias, observou-se somente efeito do sexo, sendo que as fêmeas obtiveram desempenho superior. Com relação às características de carcaça, os machos obtiveram maior rendimento de carcaças (quente, fria e dorso); já as fêmeas, apresentaram maior rendimento de cortes (peito, moela e fígado).(AU)

Accuracy in meeting nutritional requirements has great importance in quail nutrition however there is a lack of consensus on crude protein (CP) recommendations specific for European quails. The present study aimed to define crude protein requirements for European quails on performance and carcass characteristics. A completely randomized design was used in a 5 × 2 factorial scheme, with five CP levels for male and female quails. In the starting phase (1 to 21 days) it was used 1,800 quails and CP levels were 20,0, 22,5, 25,0, 27,5 and 30,0%, with six replicates containing 30 birds each. In the growth phase (22 to 45 days) it was used 1.620 quails and CP levels were 17,5, 19,5, 22,0, 24,5 and 27,0%, with six replicates containing 27 birds each. Theirs d was a corn soybean based diet in grounded form. The performance of the quails was evaluated in the end of each experimental phase and carcass yield in 45 days. Weight gain and feed conversion ratio was higher for 25,50% and 27,06% respectively, regardless of gender, in 21 days. In the growth phase, it was observed just gender effect in which female quails had higher performance. For carcass characteristics, male quails obtained higher carcass and dorse yield and female quails higher breast, liver and gizzard yields.(AU)

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The aim of this study was to evaluate diets supplemented with probiotic (Bacillus amyloliquefaciens) and organic acids (lactic, acetic and butyric acid) in attempt to replace the antibiotics and anticoccidial (avilamycin + sodium monensin) growth promoters on performance and economic viability of broilers challenged by Eimeria acervulina, E. maxima and E. tenella. A total of 900 male Cobb® chickens, with a mean weight of 39.90g, were distributed in a completely randomized design in a 2 × 2 + 1 factorial arrangement: supplementation or not of probiotic and organic acids and a treatment with inclusion of antibiotics, comprising five treatments with six replicates. For the studied performance variables, there was no effect of the isolated additives and no interaction between them (p>0.05). Only the antibiotics promoted better results for weight gain (WG), feed intake (FI) and feed conversion rate (FCR). Therefore, the use of organic acids and probiotic, isolated or associated, provided lower performance to those receiving antibiotics, not improving the performance of chickens under the imposed challenge conditions. The highest revenues were generated with the use of antibiotics, providing greater profits.(AU)

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The aim of this study was to evaluate diets supplemented with probiotic (Bacillus amyloliquefaciens) and organic acids (lactic, acetic and butyric acid) in attempt to replace the antibiotics and anticoccidial (avilamycin + sodium monensin) growth promoters on performance and economic viability of broilers challenged by Eimeria acervulina, E. maxima and E. tenella. A total of 900 male Cobb® chickens, with a mean weight of 39.90g, were distributed in a completely randomized design in a 2 × 2 + 1 factorial arrangement: supplementation or not of probiotic and organic acids and a treatment with inclusion of antibiotics, comprising five treatments with six replicates. For the studied performance variables, there was no effect of the isolated additives and no interaction between them (p>0.05). Only the antibiotics promoted better results for weight gain (WG), feed intake (FI) and feed conversion rate (FCR). Therefore, the use of organic acids and probiotic, isolated or associated, provided lower performance to those receiving antibiotics, not improving the performance of chickens under the imposed challenge conditions. The highest revenues were generated with the use of antibiotics, providing greater profits.

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The objective was to evaluate the performance, relative organ weight, morphometry, intestinal length and pancreatic enzyme activity of broilers receiving neonatal supplementation. A total of 900 Cobb 500 broiler chicks was housed in 30 boxes of 2.5 m². The treatments were divided in a completely randomized design with six replications, and consisted of five inclusion levels (0.0, 2.5, 5.0, 7.5and 10 grams per bird). The supplement used was based of amino acids, vitamins and minerals, which wasprovided on the ration on the first day in the housing. Statistical analysis was performed using SAS (2008) and when significant broken down using a polynomial regression. Due to the inclusion of the neonatal supplement in the period from one to seven and one to 21 days of age, the feed intake presented a linear effect and the weight gain, a quadratic effect. The relative weights of the gizzard and liver showed a quadratic effect, and the inclusions of 4.18 and 3.41 grams/bird provided the lowest weights, respectively. The jejunum villi height decreased with supplementation as well as the activity of pancreatic lipase. It can be concluded that neonatal supplementation benefited the performance of birds up to 21 days of age.(AU)

O objetivo foi avaliar o desempenho, peso relativo de órgãos, morfometria, comprimento intestinal e atividade de enzimas pancreáticas de frangos de corte recebendo suplemento neonatal. Foramutilizados 900 pintos de corte da linhagem Cobb 500, alojados em 30 boxes de 2,5 m². Os tratamentosforam divididos em delineamento inteiramente casualizado, com seis repetições, e consistiram em cinconíveis de inclusão (0,0; 2,5; 5,0; 7,5 e 10 gramas por ave). O suplemento utilizado foi à base de aminoácidos,vitaminas e minerais, o qual foi fornecido no primeiro dia de alojamento sobre a ração. A análise estatísticafoi realizada utilizando o SAS (2008) e quando significativos desdobrados em regressão polinomial. Em função da inclusão do suplemento neonatal no período de um a sete e de um a 21 dias de idade o consumode ração apresentou efeito linear e o ganho de peso efeito quadrático. Os pesos relativos da moela e dofígado apresentaram efeito quadrático, e as inclusões de 4,18 e 3,41 gramas/ave proporcionaram os menores pesos respectivamente. A altura das vilosidades do jejuno diminuiu com a suplementação assim como aatividade da lipase pancreática. Conclui-se que a suplementação neonatal beneficiou o desempenho das avesaté os 21 dias de idade.(AU)

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RESUMO

The objective was to evaluate the performance, relative organ weight, morphometry, intestinal length and pancreatic enzyme activity of broilers receiving neonatal supplementation. A total of 900 Cobb 500 broiler chicks was housed in 30 boxes of 2.5 m². The treatments were divided in a completely randomized design with six replications, and consisted of five inclusion levels (0.0, 2.5, 5.0, 7.5and 10 grams per bird). The supplement used was based of amino acids, vitamins and minerals, which wasprovided on the ration on the first day in the housing. Statistical analysis was performed using SAS (2008) and when significant broken down using a polynomial regression. Due to the inclusion of the neonatal supplement in the period from one to seven and one to 21 days of age, the feed intake presented a linear effect and the weight gain, a quadratic effect. The relative weights of the gizzard and liver showed a quadratic effect, and the inclusions of 4.18 and 3.41 grams/bird provided the lowest weights, respectively. The jejunum villi height decreased with supplementation as well as the activity of pancreatic lipase. It can be concluded that neonatal supplementation benefited the performance of birds up to 21 days of age.

O objetivo foi avaliar o desempenho, peso relativo de órgãos, morfometria, comprimento intestinal e atividade de enzimas pancreáticas de frangos de corte recebendo suplemento neonatal. Foramutilizados 900 pintos de corte da linhagem Cobb 500, alojados em 30 boxes de 2,5 m². Os tratamentosforam divididos em delineamento inteiramente casualizado, com seis repetições, e consistiram em cinconíveis de inclusão (0,0; 2,5; 5,0; 7,5 e 10 gramas por ave). O suplemento utilizado foi à base de aminoácidos,vitaminas e minerais, o qual foi fornecido no primeiro dia de alojamento sobre a ração. A análise estatísticafoi realizada utilizando o SAS (2008) e quando significativos desdobrados em regressão polinomial. Em função da inclusão do suplemento neonatal no período de um a sete e de um a 21 dias de idade o consumode ração apresentou efeito linear e o ganho de peso efeito quadrático. Os pesos relativos da moela e dofígado apresentaram efeito quadrático, e as inclusões de 4,18 e 3,41 gramas/ave proporcionaram os menores pesos respectivamente. A altura das vilosidades do jejuno diminuiu com a suplementação assim como aatividade da lipase pancreática. Conclui-se que a suplementação neonatal beneficiou o desempenho das avesaté os 21 dias de idade.

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