Dynamics of nitrogen concentration on intercropped ryegrass.

The dynamics of nitrogen (N) in ryegrass intercropped with different forage species with regard to dry matter (DM) accumulation within an agroecological transition system was evaluated. Annual ryegrass was intercropped with black oats (RY + BO), white clover (RY + WC) and forage peanut (RY + FP). The experimental design was completely randomized, with three replications. The study applied the N dilution model for plant tissue which comparatively uses modifiable factors of the environment at optimal levels. The model shows decline in N concentration due to the DM accumulation of temperate grass pastures. Data were compared to model by the root mean square deviation analysis. Dilution coefficient (β), used in all pasture samples, was lower than -0.60. Highest N concentration decline in plant tissues, due to DM accumulation, occurred in RY + WC pastures (β = -0.94), followed by RY + FP (β = - 0.86) and RY + BO (β = - 0.67), respectively. Ryegrass intercropped with white clover showed the highest N content in plant tissue, with a nitrogen nutrition index close to the proposed model

Pirarucu: from its origins to commercial breeding / Pirarucu: das origens ao melhoramento comercial

Because the captive breeding of pirarucu is a growing market segment with great potential, some Brazilian states in partnership with animal protection organizations and educational/research institutions have encouraged the activity, making it possible to monitor and preserve natural stocks and consequently prevent the extinction of the species. Commonly known as “pirarucu” in Brazil and “paiche” in Peru, Arapaima gigas is reported as one of the largest scaled freshwater fish in the world, with a carcass yield of around 60% and a filet yield of over 45%. The species is traditionally marketed in Brazil as a dry-salted food called “Brazilian cod”. Although much remains to be done for the captive breeding of pirarucu to be fully controlled, especially in terms of feeding and reproduction, research has been carried out with this purpose. In this scenario, the present literature review has been undertaken to elucidate the most information possible about the classification, biological aspects, production methods and breeding of pirarucu in Brazil

UTILIZAÇÃO DE RESÍDUOS INDUSTRIAIS NA DIETA DE BOVINOS LEITEIROS

This review aims at evaluating the use of industrial waste as a nutritional alternative to dairy cattle, in order to combine high production cost reduction which leads to greater gains to producers. This cost reduction may also be linked to an environmental appeal because it is waste generated by industries that are likely to be treated as waste. Some of the waste as the yerba mate industry, the residue from the brewing industry, the winemaking industry waste and citrus pulp are some examples of currently available and which arouse increasing interest of producers, researchers and industries. The residue using yerba mate industry, which carries important and proven antioxidant power emerges as an interesting alternative especially when it comes to the state of Rio Grande do Sul, where the use of yerba mate has a strong relationship with the local culture, despite still little explored for use in animal feed, this alternative comes in an interesting way to dispose the amount of waste generated. The residue from the brewing industry also brings with it the antioxidant potential and proven that can be transferred to animal products, in addition, a part of Brazilian culture and world beer consumption with high consequent generation of waste in the industry. The residue of the wine industry also has the potential addition of antioxidant constituents interesting in terms of fiber and energy and it is important to generate another source of income to wine or fruit juice industry. Citrus pulp has already consolidated its use in animal nutrition, especially when it comes to energy source because it is a waste of juices and other products industry has the differential in reducing acquisition costs. Thus, residues mentioned in this review have their different potentials exploited in order to justify their use in animal nutrition in replacement of conventional foods, both in order to maximize production costs without prejudice productivity and exploring environmental issues so prized currently have recovery of waste by industries generating income and reducing environmental contamination by disposal of these wastes into the environment.Esta revisão tem como objetivo realizar uma avaliação do uso de resíduos industriais como alternativa nutricional na alimentação de bovinos leiteiros, com o intuito de aliar alta produção com redução de custos o que leva a maiores ganhos ao produtor. Esta redução de custo ainda pode estar atrelada a um apelo ambiental por se tratar de resíduos gerados pelas indústrias que provavelmente seriam tratados como rejeitos. Alguns dos resíduos como o da indústria de erva-mate, da indústria de cervejaria, de vinificação e a polpa cítrica são alguns dos exemplos disponíveis e que despertam interesse de produtores, pesquisadores e das indústrias. O uso do resíduo da indústria de erva-mate, que apresenta comprovado potencial antioxidante surge como uma alternativa interessante principalmente para o estado do Rio Grande do Sul onde a utilização da erva-mate tem relação com a cultura local, apesar de pouco explorado para o uso da alimentação animal, esta alternativa surge de forma interessante para dar destino a quantidade de resíduo gerada. O resíduo da indústria de cervejaria também traz consigo o potencial antioxidante e que pode ser transferido aos produtos de origem animal, além disso, faz parte da cultura brasileira e mundial o consumo de cerveja com consequente alta geração de resíduos na indústria. O resíduo da indústria de vinificação possui também o potencial antioxidante além de constituintes interessantes em termos de fibra e energia e é importante para gerar mais uma fonte de renda a indústria de vinhos ou sucos da fruta. A polpa cítrica já tem seu uso consolidado na nutrição animal, principalmente no que se trata de fonte energética, por ser um resíduo da indústria de sucos e outros produtos tem o diferencial na redução de custos de aquisição. Assim, os resíduos citados nesta revisão têm seus diferentes potenciais explorados a fim de justificar sua utilização na nutrição animal na substituição de alimentos convencionais, tanto com a finalidade de maximizar custos de produção sem prejuízo a produtividade e explorando a questão ambiental tão valorizada atualmente com o aproveitamento dos resíduos pelas indústrias gerando renda e diminuindo a contaminação ambiental por eliminação destes resíduos para o ambiente

<b>Dynamics of nitrogen concentration on intercropped ryegrass</b> - 10.4025/actascianimsci.v34i1.12661

The dynamics of nitrogen (N) in ryegrass intercropped with different forage species with regard to dry matter (DM) accumulation within an agroecological transition system was evaluated. Annual ryegrass was intercropped with black oats (RY + BO), white clover (RY + WC) and forage peanut (RY + FP). The experimental design was completely randomized, with three replications. The study applied the N dilution model for plant tissue which comparatively uses modifiable factors of the environment at optimal levels. The model shows decline in N concentration due to the DM accumulation of temperate grass pastures. Data were compared to model by the root mean square deviation analysis. Dilution coefficient (β), used in all pasture samples, was lower than -0.60. Highest N concentration decline in plant tissues, due to DM accumulation, occurred in RY + WC pastures (β = -0.94), followed by RY + FP (β = - 0.86) and RY + BO (β = - 0.67), respectively. Ryegrass intercropped with white clover showed the highest N content in plant tissue, with a nitrogen nutrition index close to the proposed model

<b>Sistema laboratorial de fracionamento de carboidratos de energéticos</b> - DOI: 10.4025/actascianimsci.v28i2.652 <b>Laboratorial system of carbohydrate fractions of energetic concentrate</b> - DOI: 10.4025/actascianimsci.v28i2.652

O objetivo deste estudo foi avaliar um sistema laboratorial de fracionamento para carboidratos para identificar e quantificar as frações que compõem esse nutriente em grãos e subprodutos. Foram determinadas as frações: açúcares simples (AS) pelo método colorimétrico fenol-sulfúrico; amido disponível (AD) e amido resistente (AR) por digestões enzimáticas; fibra total (FT) pelo método enzímico-gravimétrico; fibra em detergente neutro (FDN) e fibra solúvel (FS), estimada pela diferença FT-FDN dos grãos de milho e sorgo, polpa de citrus, farelo de trigo, triguilho e farelo de arroz integral. Os coeficientes de variação para as frações AS, AD, AR, FT e FDN variaram de 4,81 a 19,17%; 4,58 a 15,03%; 2,42 a 9,91%; 1,23 a 8,23% e 1,16 a 8,42%, respectivamente, caracterizando uma boa repetibilidade das técnicas adotadas. O fracionamento identificou os principais grupos de carboidratos que compõem os alimentos e pode servir de referência para trabalhos futuros.<br>The aim of this work was to evaluate a laboratorial system of carbohydrate fractions to identify and quantify the fractions that compose this nutrient. The following fractions were determined: simple sugars (SS) using the colorimetric phenol-sulfuric method; digestible starch (DS) and resistant starch (RS) by enzymatic digestions; total fiber (TF) using the enzymic-gravimetric method; neutral detergent fiber (NDF) and soluble fiber (SF) estimated by difference TF - NDF, in grains of corn and sorghum, citric pulp, wheat middlings, wheat mills and rice bran. The coefficient of variation for fractions SS, DS, RS, TF and NDF varied from 4.81 to 19.17%; 4.58 to 15.03%; 2.42 to 9.91%; 1.23 to 8.23% and 1.16 to 8.42%; respectively. A good repeatability of the method used was observed. The fraction identified the main groups of carbohydrates composed on the food and it can be a reference to future works

CARACTERÍSTICAS PRODUTIVAS DE PASTAGENS DE MILHETO OU CAPIM SUDÃO SUBMETIDAS AO PASTEJO CONTÍNUO DE VACAS PARA ABATE

This study aimed to evaluate the productive parameters of pearl millet (Pennisetum glaucum (L.) R. BR) and Sudan grass (Sorghum bicolor cv. Sudanense) pastures, under continuous grazing by cows destined to slaughter. We used 22 crossbred Charolais and Nellore cows, kept under continuous grazing on Sudan grass or pearl millet pastures, over 63 experimental days, divided into three periods (21 days each). The experimental design was completely randomized with two treatments and three periods, with five replicates (area). The productive parameters of the pastures were similar when treatments were compared (P < 0.05). The growing cycle of pastures did not affect forage mass (1617.47 and 1606.93 kg of dry matter (DM)/ha) and forage offer (9.42 and 8.29 kg of DM/100 kg BW) on pearl millet or Sudan grass pastures. However, the average rate of accumulation of dry matter and crude protein showed higher values ​​on the first 21 days of pasture use (130.77 kg DM/ha and 17.04 g/kg DM), followed by reductions in the last two periods, and the averages of the second period (65.53 kg DM/ha and 12.96 g/kg DM) were higher than those of the third experimental period (36.13 kg DM/ha and 10.01 g/kg DM). The values ​​for neutral detergent fiber were similar in the two earlier periods (48.81, 49.01g/kg DM), followed by an increase in the last 21 days of pasture use (56.54 g/kg DM). The stocking rate in kg/ha of BW showed an interaction between treatment and period, however, the mean values ​​were similar between treatments (1741.1 kg/ha of the BW for pearl millet and 1881.7 kg/ha of BW for Sudan grass). The average daily live weight gain did not differ between treatments (1.04 for pearl millet and 0.96 for Sudan). The average daily gain per area (4.18, 4.55 kg/ha of BW) was similar on the first 42 days of pasture use and higher than on the last 21 experimental days (2.39 kg / ha of BW). Pearl millet or Sudan grass pastures are equivalent with respect to the production characteristics under continuous grazing by culling cows

Produção, caracterização nutricional e fermentativa de silagens de sorgo forrageiro e sorgo duplo propósito = Production, fermentation and nutritional characteristics of forage and double purpose sorghum silages

Objetivou-se com o trabalho avaliar a produtividade de cinco híbridos de sorgo forrageiro e cinco híbridos de sorgo duplo propósito, bem como caracterizar os parâmetros fermentativos e nutricionais das silagens confeccionadas a partir desses materiais. O delineamento experimental foi de blocos ao acaso, com três repetições portratamento. Os resultados foram submetidos à análise de variância e as médias dos híbridos, submetidas ao estudo de contrastes ortogonais, sorgo forrageiro “versus” sorgo duplo propósito. Todos os híbridos apresentam condições de ensilagem por meio da avaliação dos parâmetros fermentativos. As silagens elaboradas a partir de sorgoforrageiro apresentam menor teor de MS (33,01%) e pH (3,86), contra 38,32% de MS e 3,97 de pH das silagens de sorgo duplo propósito. Silagens de sorgo forrageiro e sorgo duplo propósito apresentam valor nutricional semelhantes, porém, as silagens de sorgo duplo propósito apresentam maior teor de CEL (25,30%) e K (1,16%). Os híbridos desorgo forrageiro produziram em média 17.527 kg ha-1 de MS, superior à produtividade média dos híbridos de sorgo duplo propósito de 13.006 kg ha-1 de MS.<br><br>This work was set out to evaluate productivity, nutritional and fermentation characteristics of different sorghum cultivar silages. The experimental design was randomized blocks with three replications. The results were submitted to ANOVA and mean values of each cultivar were used for an orthogonal contrasts study (forage sorghum vs. double purpose sorghum silages). Results of fermentative characteristics showed that all cultivars presented potential forensilage. Double purpose sorghum silages showed higher (p < 0.05) dry matter content (38.32%) when compared to forage sorghum silage (33.01%), as well as for pH values. Likewise, double purpose sorghum silages showed significant, increased levels of CEL (25.30%) and K (1.16%). Forage sorghum cultivars showed higher (p < 0.05) productivity (17527 kg ha-1 of dry matter) when compared to double purpose sorghum productivity (13006 kg ha-1 of dry matter)