The objective of the present study was to perform a meta-analysis that compared the chemical composition of corn silage produced for different experimental purposes, i.e., by research groups that studied corn silage (SCS) or by research groups that only used corn silage (UCS) as a form of roughage. We analyzed 203 papers that were published between January 1994 and December 2014 and contained a total of 647 treatments and the analysis of 1701 silos. We found a significant difference (P < 0.0001) in the dry matter (DM) content of SCS silage (33.00%) and that of UCS silage (30.64%). The DM contents of neutral detergent fiber for the SCS and UCS silage were high (54.72 and 55.14% DM, respectively) but were not significantly different from one another (P = 0.5936), and the acid detergent fiber content of the UCS silage (31.04% DM) was higher than that of the SCS silage (29.65%, P = 0.0214), which indicated that the UCS silage was less digestible than the SCS silage. This was also corroborated (P = 0.0064) by the mean content of total digestible nutrients (64.18% DM) in the UCS silage, which likely results from the lower level of care taken when using standard silage production methods, compared to that taken by SCS researchers. Therefore, we concluded that the corn silage produced by research groups in Brazil are not analyzed in full and that, as a result, there is a paucity of important information, such as the content of organic acids. In addition, we also found that corn silage produced in Brazil contains a high level of neutral detergent fiber. Key words: Starch. Carbohydrate. Fiber. Ruminant. Conserved roughage. Zea mays. ResumoObjetivou-se analisar metanaliticamente a composição bromatológica de silagens de milho, estudadas ou utilizadas em dietas para ruminantes, em condições experimentais brasileiras. Foram utilizados artigos publicados entre janeiro de 1994 e dezembro de 2014, totalizando 203 artigos científicos com 647 tratamentos, envolvendo a análise de 1.701 silos. Observou-se diferença (P < 0,0001) no teor de matéria seca (MS) encontrado nas silagens entre pesquisas que estudam especificamente silagem de milho (ESM, de 33,00% de MS), para as que utilizam silagem de milho como suporte em outras avaliações científicas USM, 30,64% de MS). Os teores de fibra em detergente neutro são elevados para ESM (54,72% da MS) e para USM (55,14% da MS), não havendo diferença (P=0,5936). As USM apresentam valores maiores (P = 0,0214) de fibra em detergente ácido (FDA) (31,04% da MS), ou seja, fornecem volumoso de menor digestibilidade que as ESM. Este fato é também corroborado (P = 0,0064) pelo nível médio de nutrientes digestíveis totais (NDT) (64,18% da MS) nos estudos USM, pois geralmente não há o mesmo cuidado com as premissas básicas de produção de silagem, comparado com o grupo ESM cujas silagens apresentaram em média 29,65% de FDA e 66,79% de NDT. As silagens de milho de planta inteira produzidas em condições experimentais no Brasil não são analisadas por completo, faltam informações imprescindíveis como...

Recebido em 19/6/08; aceito em 29/6/09; publicado na web em 27/11/09 ORGANIC MATTER IN FOUR BRAZILIAN SOIL TYPES: CHEMICAL COMPOSITION AND ATRAZINE SORPTION. Soil organic matter is the main sorptive soil compartment for atrazine in soils, followed in a minor scale by the inorganic fraction. In this study, the soil organic matter quality and atrazine sorption were investigated in four different soil types. The pedogenic environment affected the humification and therefore the chemical composition of the organic matter. The organic matter contribution to atrazine sorption was larger (60-83%) than that of the inorganic fraction. The organic matter capacity in retaining the herbicide was favoured by a higher decomposition degree and a smaller carboxylic substitution of the aliphatic chains.

Currently, the practice of Crop-Livestock Integration is stimulated as a way of increasing the generation of foreign exchange for Brazil. Integrated systems improve land use efficiency as well as preserve, recover and increment or soil fertility. The aim of this research was to evaluate how different doses of nitrogen fertilization can affect production and quality of dual purpose wheat submitted to grazing. The experimental designed was randomized block with five treatments (0, 75, 150, 225 and 300 Kg N ha -1 , like ammonium nitrate) and four repetitions. The forage yield, the percentage crude protein (P=.0001) and acid detergent insoluble protein (P=.0054) had a linear increased because of the nitrogen addition doses. The crude protein percentage changed the estimate of all soluble carbohydrates (P=.0001) and non-fibrous carbohydrates (P=.0186), but did not influence the, nitrogen detergent fiber corrected with ash and proteins percentage contributing for content cell. The crops production (P=.0001) and the number of kernels per ear (P=.0001) showed significantly difference because of the nitrogen additions dose, increasing the number of fertile flowers. The nitrogen topdressing alters forage production, the chemical composition and the production of dual purpose wheat grains subjected to grazing. Key words: Meat. Fertility. Grain. Crop livestock integration. Milk. Pasture. ResumoAtualmente, é estimulada a prática de Integração Lavoura-Pecuária (ILP) como forma de incrementar a geração de divisas para o Brasil. Os sistemas integrados melhoram a eficiência de uso da terra, bem como preservam, recuperam e/ou incrementam a fertilidade do solo. Objetivou-se avaliar a produção e a composição bromatológica de trigo duplo propósito (TDP) manejado sob pastejo com diferentes doses de nitrogênio em cobertura (DAN): 0, 75, 150, 225 e 300 Kg de N ha -1 , sob a forma de nitrato

Nitrogen fertilization can be used to increase production for area, as well as to improve the grains nutritional value. The aim of this study was to evaluate the chemical composition of two linseed cultivars (Brown and Golden) submitted to increasing doses of nitrogen fertilization in a completely randomized design. The Brown and Golden flax sowing was in April 2014, using 40 kg of viable seeds ha -1 and 100 kg ha -1 of diammonium phosphate (16-46-00) as fertilizer. It was evaluated the increasing doses of N fertilization in the cover: 0, 50, 100, 150 and 200 kg of N ha -1 , applied in the urea form. For the fatty acids (FA) analysis, a composite sample of each variety was performed for the treatment 0 and 200 kg N ha -1 . The composite samples were grounded in a multi-use mill with cooling jacket. The cooling was aimed to avoid the heating of the samples during their processing, in order to reduce the chances of FA profile alterations. The application of nitrogen positively influenced the production of grains and oil ha -1 of the cultivars, improved the Brown flax dry matter in vitro digestibility and the Golden flax neutral detergent fiber, ether extract and crude protein amounts. The cultivar Brown flax presented higher production of grains and oil ha -1 when compared to Golden flax, which presented lower neutral detergent fiber, crude protein, total carbohydrates and higher amounts of ether extract. The Golden flax was nutritionally healthier, as it presented higher proportions of C18:3 n3, unsaturated fatty acids, unsaturated/saturated fatty acids and hypocholesterolemic index. Both cultivars have potential ingredients to be used in animal feed, aiming to improve the quality of the final product. ResumoA adubação nitrogenada pode ser utilizada para aumentar a produção por área, além de melhorar o valor nutricional dos grãos. Objetivou-se avaliar a composição bromatológica de duas cultivares de 1 Prof Osmari, M. P. et al.linhaça (Marrom e Dourada) submetidas a níveis crescentes de adubação nitrogenada, em delineamento inteiramente casualizado. A semeadura da linhaça Marrom e Dourada ocorreram em abril de 2014, utilizando 40 kg de sementes viáveis ha -1 e 100 kg ha -1 de fosfato diamônico (16-46-00) como fertilizante. Foram avaliadas as doses crescentes de adubação nitrogenada em cobertura: 0, 50, 100, 150 e 200 kg de N ha -1 , aplicadas na forma de ureia. Para a análise dos ácidos graxos (AG), foi realizada uma amostra composta de cada variedade para o tratamento 0 e 200 kg N ha -1 . As amostras compostas foram moídas em um moinho multiuso com refrigeração. O resfriamento teve como objetivo evitar o aquecimento das amostras durante o processamento, a fim de reduzir as chances de alterações no perfil do AG. A aplicação de nitrogênio influenciou positivamente a produção de grãos e óleo ha -1 das cultivares, melhorou a digestibilidade in vitro da matéria seca da linhaça e a quantidade de fibra em detergente neutro, do extrato etéreo e da proteína bruta. A cultivar Marrom apresentou maior produção de grãos e óleo...

Uma alternativa, empregada pelos produtores do cereal trigo, para garantir produtividade é a aplicação de herbicidas dessecantes na pré-colheita. No entanto, essa prática pode acarretar na contaminação química do produto colhido. Diante do exposto, objetivou-se com a presente revisão, fazer um levantamento, a partir de estudos científicos, sobre o efeito da dessecação na pré-colheita do trigo com o uso de herbicidas, na qualidade fisiológica dos grãos de trigo destinados ao consumo humano e animal. No Brasil, a região Sul tem a maior área cultivada com este cereal, 1.714 milhões de hectares em 2017. Nos últimos anos os produtores rurais, a fim de minimizar a deterioração da qualidade dos grãos no campo e garantir a produtividade, passaram a adotar a prática de aplicação de herbicidas dessecantes na pré-colheita. Entretanto, essa prática pode resultar no transporte dos produtos químicos até os grãos ou sementes, resultando na contaminação química do produto final, onde, em sua grande maioria é destinado à produção de farinha. Os resultados da revisão bibliográfica são heterogêneos, apresentando em alguns casos efeitos negativos da dessecação em pré-colheita aos grãos e/ou sementes, enquanto em outros não existe a mesma constatação. Dessa forma, o produtor sempre que utilizar um defensivo agrícola, deve seguir o receituário agronômico, bem como ficar atento às indicações da bula do produto, de modo a respeitar as doses e período de carência entre aplicação e colheita. Ainda há a necessidade de técnico especializado, necessidade de tal procedimento, viabilidade em determinada localidade, registro dos produtos químicos para este fim e se estes deixam resíduos nos grãos que possam comprometer a saúde humana.

Nowadays, there are numerous arrangements of Integrated Systems of Agricultural Production, due, the particularities of each region and/or rural enterprise. The use of dual-purpose species such as, for example, BRS Tarumã® wheat further intensifies the system, because there is plant-animal production in a short time. Study aimed to evaluate the production and chemical composition of dual purpose wheat pastures managed with different DAN during periods of spikelet terminal (ST) and anthesis (AN), aiming crop production (pasture and grain) and animal (milk and / or meat). The experimental randomized block design with five treatments (0, 75, 150, 225 e 300 Kg de N ha, in the form of ammonium nitrate) and four replications. The average biomass values before the first and the second grazing were respectively: 2,164 and 2,127 kg DM per hectare and the waste of about 824 and 1,772 kg of DM per hectare and the daily average accumulation rate between the two grazing DM was 86 kg per hectare at 17 day intervals. The variables, number of spikes per square meter, grain number per square meter, thousand grain weight, hectoliter weight and grain yield did not differ (P>0.05) between treatments. Nitrogen fertilization increases linearly (P=0.0017) the size of the spikes depending on nitrogen rates. For the linear variable layering increased (P=0.0001), indicating the susceptibility of the crop to high levels of nitrogen. The application of nitrogen fertilizer levels in dual purpose grazed wheat before the spikelet terminal stage and anthesis does not influence on grain yield variables. The nitrogen fertilization on wheat double purpose must be fractionated at tillering and after each grazing increasing the remobilization rate of nitrogen by culture.

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This longitudinal retrospective study evaluated production and composition of milk from dairy cows according to season on a rural property in Palmeira das Missões, Rio Grande do Sul, Brazil, between January 2009 and December 2016. Milk yield per hectare per month was the primary variable measured, along with chemical composition (total dry extract, defatted dry extract, fat, protein, and lactose), somatic cell count, and total bacterial count of milk. Production in summer (513.53 kg/ha/month) did not differ (p > 0.05) from that in fall (504.69 kg/ha/month) or spring (564.63 kg/ha/month), but production in winter (639.20 kg/ha/month) was significantly higher than in summer (p < 0.0057). The real price of milk did not differ (p > 0.05) among seasons. The total dry extract content differed (p < 0.0059) between seasons. However, the cooler fall and winter seasons favored the production of total solids. The defatted dry extract content was higher (p < 0.0001) in winter (8.65%), compared to the other seasons of the year. Fat content did not differ (p > 0.05) among seasons. Protein content differed (p < 0.0200) between summer (3.01%) and winter (3.16%), but both seasons did not differ (p > 0.05) from fall (3.13%) or spring (3.05%). Winter lactose levels (4.52%) were higher (p < 0.0011) than during other seasons. The somatic cell count did not differ (p > 0.05) among seasons, demonstrating that the evaluated herd possesses standard mammary gland health. The total bacterial count did not differ (p > 0.05) among the seasons, demonstrating that the hygiene of the facilities remains constant. As expected, the temperature and humidity index varied (p < 0.0001) with the seasons, and the deleterious effects were more pronounced in summer and spring, as they are the hottest seasons in humid subtropical environments. The results emphasize that the organized management of milk production reduces the variation in milk composition, making it easier to maintain a consistent high milk quality and also generating extra revenue.