RESUMO

Chicken feed efficiency (FE) traits are the most important economic traits in broiler production. Several studies evaluating genetic factors affecting food consumption in chickens are available. However, most of these studies identified genomic regions containing putative quantitative trait loci for each trait separately. It is still a challenge to find common gene networks related to these traits. Therefore, here, a genome-wide association study (GWAS) was conducted to explore candidate genomic regions responsible for Feed Intake (FI), Body Weight Gain (BWG) and Feed Conversion Ratio (FCR) traits and their gene networks. A total of 1430 broilers from an experimental population was genotyped with the high density Affymetrix 600K SNP array. A total of 119 associated SNPs located in 20 chromosomes were identified, where some of them were common in more than one FE trait. In addition, novel genomic regions were prospected considering the SNPs dominance effects and sex interaction, identifying putative candidate genes only when these effects were fit in the model. Relevant candidate genes such as ATRNL1, PIK3C2A, PTPRN2, SORCS3 and gga-mir-1759 were highlighted in this study helping to elucidate the genomic architecture of feed efficiency traits. These results provide new insights on the mechanisms underlying the consumption and utilization of food in chickens.

Assuntos

RESUMO

Corn and grass intercropping is an interesting practice, and forage plants belonging to the genus Urochloa are the most commonly used in these situations. These plants show excellent adaptation to low-fertility soil, easy establishment, considerable biomass production, as well as being an important competitor with weeds. In agrosilvopastoral systems, the yield of corn crops grown together with trees is hindered due to the reduced radiation incidence caused by tree shading. This study aimed to evaluate corn growth, light interception, and chlorophyll content when intercropped with marandu grass in an agrosilvopastoral system with one and three eucalyptus rows, and compare them with plants under full sun. The experiment was conducted in Andradina SP (Brazil). Treatments consisted of intercropping with no eucalyptus (plants under full sun: control), one system with one eucalyptus row and another with three rows. We also assessed the effect of five distances between corn plants and eucalyptus trees (2, 4, 6, 8, and 10 m). Between eucalyptus rows, corn plants were intercropped with marandu grass. The analyzed variables were corn plant height, ear height, chlorophyll content index, light interception, dry matter, and fresh and dry forage weights. The experimental design was a randomized block in a factorial scheme plus a control, with four repetitions. Tree arrangements had no influence on corn forage, dry matter, plant height, or ear height. Lower results of yield, dry matter, plant height, and ear height were observed for plants spaced 2 m from trees.(AU)

O uso do cultivo de milho com capim é interessante no consórcio, sendo as forrageiras do gênero Urochloa são as mais utilizadas, destacando-se por apresentar excelente adaptação aos solos de baixa fertilidade, fácil estabelecimento, considerável produção de biomassa e importante competidora com espécies daninhas das culturas anuais. Nos sistemas agrossilvipastoris a produtividade do milho cultivado sob árvores é influenciada em função da diminuição da radiação causada pelo sombreamento. O objetivo do trabalho foi avaliar o desenvolvimento, interceptação luminosa e índice de conteúdo de clorofila (ICC) do milho consorciado com capim-marandu em sistema agrossilvipastoril com 1 linha de eucalipto, 3 linhas de eucalipto e a pleno sol. O experimento foi conduzido na APTA Andradina, SP e os tratamentos foram: sem eucalipto (pleno sol: controle), sistemas com eucalipto (1 e 3 linhas) e dentro destes, cinco distâncias em relação às árvores (2, 4, 6, 8 e 10 m). Entre os renques de eucalipto foi utilizado o sistema de integração com o milho consorciado com capim-marandu. Foram avaliadas as seguintes características produtivas do milho: altura de planta, altura de inserção de espiga, ICC, interceptação luminosa, produção de massa verde, matéria seca e massa seca de forragem do milho. O delineamento experimental foi em blocos casualizados em arranjo fatorial com tratamento adicional (controle) tendo quatro repetições. A produtividade da forragem de milho, matéria seca, altura das plantas na colheita e altura de inserção de espiga não foram influenciadas pelos arranjos de árvores. .(AU)

Assuntos

RESUMO

Corn and grass intercropping is an interesting practice, and forage plants belonging to the genus Urochloa are the most commonly used in these situations. These plants show excellent adaptation to low-fertility soil, easy establishment, considerable biomass production, as well as being an important competitor with weeds. In agrosilvopastoral systems, the yield of corn crops grown together with trees is hindered due to the reduced radiation incidence caused by tree shading. This study aimed to evaluate corn growth, light interception, and chlorophyll content when intercropped with marandu grass in an agrosilvopastoral system with one and three eucalyptus rows, and compare them with plants under full sun. The experiment was conducted in Andradina – SP (Brazil). Treatments consisted of intercropping with no eucalyptus (plants under full sun: control), one system with one eucalyptus row and another with three rows. We also assessed the effect of five distances between corn plants and eucalyptus trees (2, 4, 6, 8, and 10 m). Between eucalyptus rows, corn plants were intercropped with marandu grass. The analyzed variables were corn plant height, ear height, chlorophyll content index, light interception, dry matter, and fresh and dry forage weights. The experimental design was a randomized block in a factorial scheme plus a control, with four repetitions. Tree arrangements had no influence on corn forage, dry matter, plant height, or ear height. Lower results of yield, dry matter, plant height, and ear height were observed for plants spaced 2 m from trees.

O uso do cultivo de milho com capim é interessante no consórcio, sendo as forrageiras do gênero Urochloa são as mais utilizadas, destacando-se por apresentar excelente adaptação aos solos de baixa fertilidade, fácil estabelecimento, considerável produção de biomassa e importante competidora com espécies daninhas das culturas anuais. Nos sistemas agrossilvipastoris a produtividade do milho cultivado sob árvores é influenciada em função da diminuição da radiação causada pelo sombreamento. O objetivo do trabalho foi avaliar o desenvolvimento, interceptação luminosa e índice de conteúdo de clorofila (ICC) do milho consorciado com capim-marandu em sistema agrossilvipastoril com 1 linha de eucalipto, 3 linhas de eucalipto e a pleno sol. O experimento foi conduzido na APTA – Andradina, SP e os tratamentos foram: sem eucalipto (pleno sol: controle), sistemas com eucalipto (1 e 3 linhas) e dentro destes, cinco distâncias em relação às árvores (2, 4, 6, 8 e 10 m). Entre os renques de eucalipto foi utilizado o sistema de integração com o milho consorciado com capim-marandu. Foram avaliadas as seguintes características produtivas do milho: altura de planta, altura de inserção de espiga, ICC, interceptação luminosa, produção de massa verde, matéria seca e massa seca de forragem do milho. O delineamento experimental foi em blocos casualizados em arranjo fatorial com tratamento adicional (controle) tendo quatro repetições. A produtividade da forragem de milho, matéria seca, altura das plantas na colheita e altura de inserção de espiga não foram influenciadas pelos arranjos de árvores. .

Assuntos