The objective of the present study was to use electrical bioimpedance analysis (BIA) as an alternative method of evaluating the quality of bovine raw milk. Fourteen lactating purebred Dutch cows were used. For the analyses of milk quality and electrical bioimpedance, 140 ml milk per mammary quarter and a homogeneous sample of each animal were collected, totalling 70 samples. The criteria used to evaluate milk quality consisted of somatic cell count (CCS), total bacterial count (CBT), fat, protein, lactose, total solids (ST) and non-greasy solids (SNG) as required by IN No 62/2011. A monofrequential 50 kHz and 800 μA alternating current generator was used for electrical BIAs. The temperature of the raw milk was 5 °C for all samples. Primary resistance and reactance readings were obtained. From these values, the values of impedance, conductance and phase angle were obtained. Correlation analyses were performed to determine the variables used by the regression analyses. The regression analysis was performed using raw milk components as dependent variables and BIA measurements as independent variables. Lactose, ST and SNG were the components of milk that correlated best and presented moderate prediction equations in relation to BIA variables. The prediction equations using resistance showed R2 of 0.42 and 0.45 for ST and SNG, respectively. In the prediction equation for ST and SNG, the conductance resulted in R2 of 0.45, and 0.45, respectively. Regarding impedance, the R2 of 0.42 and 0.45 were obtained for the predicted equations ST and SNG, respectively. Thus, it can be concluded that BIA has the potential to estimate the composition and quality of bovine raw milk.

The objective of this study was to, through a meta-analysis of published data, evaluate the effects of dietary supplementation on the performance of beef cattle grazed on Brachiaria pastures during the rearing and finishing phases of growth. Data from 15 Brazilian studies were analyzed, totaling 462 animals given different types and levels of supplementation. Animals were divided into two categories: 319 in the rearing phase, and 143 in the finishing phase. The reviewed studies evaluated the effects of protein, energy, and protein/energy supplementation on animal performance parameters. Daily weight gain and final live weight were analyzed using forest plots. Daily weight gain during the rearing phase was similar across all supplement types used. Animals given supplementation gained an average of 119 g more per day compared to those who received no supplementation. Specifically, protein supplementation resulted in an increase of 28.22 kg. Animals given supplementation of any kind, represented by the subgroups shown in the plots, gained an average of 24.47 kg more compared to the control group.

A inoculação com Azospirillum brasilense apresenta potencial de uso na cultura do sorgo (Sorghum bicolor [L.] Moench) pela possibilidade de alterar a fisiologia e morfologia das plantas. Neste sentido, o presente estudo tem por objetivo avaliar a influência da inoculação via semente com a bactéria promotora de crescimento da estirpe Azospirillum brasilense sobre a composição morfológica, parâmetros fermentativos, perdas nutricionais, frações nitrogenadas e de carboidratos em silagem de sorgo do híbrido AG 2005. O delineamento experimental foi o inteiramente casualizado, constituindo-se de dois tratamentos (com e sem inoculação), com quatro repetições de silos. O fracionamento nitrogenado, foi determinado conforme descrito por Licitra et al. (1996) e para mensurar o fracionamento dos carboidratos, foi avaliado de acordo com a metodologia proposta por Lanzas et al. (2007). As plantas inoculadas apresentaram menor porcentagem de colmo, mas houve maior participação de panícula mais grãos. O híbrido inoculado produziu silagem com menor teor de nitrogênio insolúvel em detergente ácido (NIDA) e nitrogênio insolúvel em detergente neutro (NIDN). Com relação ao fracionamento de carboidratos, as silagens de sorgo com inoculação diferiram significativamente em CHO (carboidratos totais) e CC (fibra indigestível) em relação ao controle. Sobre o fracionamento proteico, a fração   indigestível (PC), a inoculação apresentou redução de 0,29 unidade percentuais quando comparado ao controle. Desta forma, a inoculação de sementes com A. brasilense pode ser uma alternativa viável, pois apresenta potencial de reduzir a fração de proteína e glicídios insolúvel e indigestível no trato gastrointestinal em silagens de sorgo.

With the aim to evaluate the effects of the use of additives (milk whey and inoculant containing Lactobacillus casei and Lactobacillus acidophillus) in sorghum silage, an experiment was conducted in which the productive parameters, fermentative and the nutritional quality of silage were analyzed. The experimental design was completely randomized, testing different levels of inclusion of whey and live Lactobacillus strains based on forage green matter, constituting the following treatments: 1) Sorghum without inclusion of additives (CON); 2) Sorghum + 5 x 10 2 cfu/g L. casei and L. acidophillus (LAC); 3) Sorghum 5 x 10 2 cfu g-1 whey (SL); 4) Sorghum + 5x10 2 cfu/g-1 L. casei and L. acidophillus and 5x10 2 cfu/g whey (LAC + SL). When Lactobacillus was included the mixture used was 50 ml of water and 10 grams of Lactobacillus. To measure silage fermentation, pH, dry matter recovery, gas and effluent losses, ammonia nitrogen, buffer power and density were estimated. The addition of whey and Lactobacillus inoculant in sorghum silage did not significantly change the bromatological values of silage when compared to the original material. The inclusion of additives increased (P <0.05) the effluent losses during fermentation. The use of whey presents a viable alternative for producers, as it does not compromise the fermentation and chemical composition of sorghum silage and assists in the reduction of dairy residues in nature.KEY WORDS: silage, fermentation, grass, by-product. EFEITO DA ADIÇÃO DE ADITIVOS: SORO DO LEITE, LACTOBACILLUS CASEI E ACIDOPHILLUS SOBRE A QUALIDADE DA SILAGEM DE SORGORESUMO: Com o objetivo de avaliar os efeitos do uso de aditivos (soro de leite e inoculante contendo Lactobacillus casei e L. acidophillus) em ensilagem de sorgo, foi conduzindo um experimento em que se analisou os parâmetros produtivos, fermentativos e a qualidade nutricional das silagens. O delineamento experimental foi o inteiramente casualizado, sendo testados diferentes níveis de inclusão de soro de leite e cepas de Lactobacillus vivos com base na matéria verde da forragem, constituindo os seguintes tratamentos: 1) Sorgo sem inclusão de aditivos (CON); 2) Sorgo + 5 x10 -2 ufc g -1 L. casei e L. acidophillus (LAC); 3) Sorgo 5 x10 -2 ufc g -1 soro de leite (SL); 4) Sorgo + 5x10 -2 ufc g -1 L. casei e L. acidophillus e 5x10 -2 ufc g -1 de soro de leite (LAC+ SL). Quando houve inclusão de Lactobacillus a mistura utilizada foi 50 ml de água e 10 gramas de Lactobacillus. Para mensurar a fermentação da silagem, estimou-se o pH, recuperação de matéria seca, perdas de gases e efluentes, nitrogênio amoniacal, poder tampão e densidade. A adição de soro de leite e do inoculante com Lactobacillus na ensilagem de sorgo, não modificou significativamente os valores bromatológicos da silagem, quando comparada ao material original. A inclusão dos aditivos aumentou (P<0,05) as perdas por efluentes durante a fermentação. A utilização do soro de leite apresenta uma alternativa viável para os produtores, pois não compromete a fermentação e a composiç...

Bioelectrical impedance analysis (BIA) is a method based on the different levels of opposition to the flow of an ionic current through the different body tissues. Results are expressed by primary measures of resistance (Rs) and reactance (Xs). From such measures, equations are applied to determine the phase angle (PA) and impedance (Z). Bioimpedance analysis has been indicated as a reliable and precise method to determine the body composition and nutritional status in humans. BIA has recently been adapted to be applied on animal production. Therefore, the aim of this review is to provide an analysis on the potential use of bioelectrical impedance on zootechnical production. Through BIA, correlations among bioelectrical measures and tissue composition of swine, bovine, ovine, bubaline and fish carcasses can be established. In this regard, a growing number of demands were led by more precise and cost-effective methods to evaluate the body composition in the zootechnical sector, in which the analysis of bioelectrical impedance proved to be a promising and minimally invasive technology to replace traditional methods.

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The experiment evaluated the effects on the chemical composition (fermentation, kinetic parameters, and protein and carbohydrate fractions) of corn silage after various storage durations (45, 90, 180, and 360 days). Experimental mini silos of the corn plants were made and opened after various storage periods. The experimental design was completely randomized with four treatments and four replications per treatment. Variables such as pH, lactic acid and acetic acid showed a quadratic effect, whereas effluent and gas losses increased linearly with prolonged storage. Proteolysis was observed with an increase in storage, resulting in a rise in ammonia-N, soluble N, and non-protein N concentration and reduction in true protein. The soluble carbohydrate fractions were reduced, and digestible and indigestible fibre were increased. For the kinetic degradation parameters of the silages obtained through in vitro gas methodology, the highest fermentation rate occurred in the first 12 hours of incubation, and the highest volume of gas produced within 96 hours was obtained for silages with shorter storage (45 days). The increase in storage resulted in greater losses and lower ruminal degradability in vitro, causing a decrease in protein quality and nutritional value.

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