Geraldo Tadeu dos Santos

Degradabilidade in situ do farelo de canola tratado com calor e/ou tanino

The objective of this work was to evaluate the in situ disappearance of canola meal treated with water (control), in autoclave at 127oC for 30 min (CC), with 15% of Acacia mearnsii tannin (CT) and tannin followed by autoclaving (CTC). The effect of these treatments on in situ disappearance of dry matter (DM) and crude protein (CP) was evaluated by the nylon bag technique, using two rumen fistulated Holstein cows. The estimates of effective degradation of DM for control, CC, CT and CTC were 74.5, 64.2, 75.1, and 70.5%, and effective degradation of CP were 86.5, 64.0, 82.6, and 69.9%, respectively, assuming rumen of 5%/h outflow rate. No effect of tannin treatment on DM degradation was reported, however, there was a small influence on CP degradation. The treatments (CC and CTC) reduced DM and CP degradation. The heating effect, after tannin treatment, was smaller than its isolated effect, resulting in significant interaction. The heat treatment was the most effective to reduce ruminal degradation of canola meal DM and CP.The objective of this work was to evaluate the in situ disappearance of canola meal treated with water (control), in autoclave at 127oC for 30 min (CC), with 15% of Acacia mearnsii tannin (CT) and tannin followed by autoclaving (CTC). The effect of these treatments on in situ disappearance of dry matter (DM) and crude protein (CP) was evaluated by the nylon bag technique, using two rumen fistulated Holstein cows. The estimates of effective degradation of DM for control, CC, CT and CTC were 74.5, 64.2, 75.1, and 70.5%, and effective degradation of CP were 86.5, 64.0, 82.6, and 69.9%, respectively, assuming rumen of 5%/h outflow rate. No effect of tannin treatment on DM degradation was reported, however, there was a small influence on CP degradation. The treatments (CC and CTC) reduced DM and CP degradation. The heating effect, after tannin treatment, was smaller than its isolated effect, resulting in significant interaction. The heat treatment was the most effective to reduce ruminal degradation of canola meal DM and CP.

Avaliação dos efeitos de fontes de fósforo na dieta sobre parâmetros do meio ruminal e eficiência de síntese microbiana, digestibilidade dos nutrientes e fósforo plasmático em bovinos

Este trabalho foi conduzido com os objetivos de avaliar o efeito de fontes de fosforo em dietas para bovinos em crescimento sobre o coeficiente de digestibilidade parcial e total dos nutrientes, os parâmetros ruminais, a eficiencia de sintese microbiana e os niveis plasmaticos de fosforo. Foram utilizados quatro bovinos castrados, raca Holandesa Preto e Branco (280 kg de peso vivo), com cânula ruminal e duodenal, em delineamento quadrado latino 4 × 4, com quatro fontes de fosforo (fosfato bicalcico - BIC; superfosfato triplo - SPT; fosfato monoamonio - MAP; e fosfato de rocha Araxa - FRA). As fontes de fosforo nao afetaram a ingestao, o fluxo fecal, as digestibilidades ruminal, duodenal e total de materia seca, materia orgânica, proteina bruta, fibra em detergente neutro e carboidratos nao-fibrosos. A absorcao de fosforo do fosfato de rocha Araxa foi menor e diferiu da absorcao do fosfato bicalcico e do fosfato monoamonio. Os animais que receberam fosfato de rocha Araxa apresentaram maiores ingestao, fluxo fecal, fluxo duodenal, desaparecimento ruminal e desaparecimento fecal de fluor (F). A utilizacao de fosfato de rocha Araxa resultou em niveis de fluor na dieta superiores aos recomendados para evitar sua toxidez. As fontes de fosforo nao alteraram os niveis plasmaticos de fosforo nem a ingestao de nitrogenio, a eficiencia de sintese microbiana e a composicao das bacterias ruminais. Tambem nao influenciaram o pH ruminal e as concentracoes de NH3-ruminal. Estes resultados indicam que e possivel o uso do superfosfato triplo e do fosfato monoamonio em substituicao ao fosfato bicalcico.

Características morfológicas e índice de área foliar do capim-tanzânia (Panicum maximum Jacq. cv. Tanzânia-1) manejado em diferentes alturas, sob pastejo

The effect of different sward heights (24, 26, 43, 45, 52, 62, 73 and 78 cm) and different sampling periods (28, 56, 84 days), on basal and aerial tiller density, weight and diameter of basal tillers, leaf area index (LAI), meristem apical height, node number and internode length basal tiller in Tanzaniagrass (Panicum maximum Jacq. cv. Tanzânia - 1) is provided. Nelore steers were used in grazing, with variable stocking rates, using put and take techniques. The experimental design was completely randomized, with two replications. Aerial tiller density, weight, diameter, node number and internode length basal tiller, apical meristem height and leaf area index increased according to the higher sward management height. Basal tillering was not affected by sward management heights, but decreased during the experiment. Aerial tiller had a similar behavior. Node number, internode length, apical meristem height and LAI had a negative quadratic behavior, according to the sample collection period.

Qualidade da silagem de grãos de milho com adição de soja crua e parâmetros de digestibilidade parcial e total em bovinos

Avaliou-se a qualidade da silagem de graos umidos de milho com adicao de soja crua, por meio de medidas de digestibilidade parcial e total em bovinos. Foram utilizados tres animais mesticos Nelore x Red Angus, implantados com cânulas ruminal e duodenal. O delineamento experimental foi o quadrado latino 3x3, com os seguintes tratamentos: SGM66= 60% de volumoso, 26,6% de silagem de graos de milho e 13,4% de farelo de soja e milho moido; SGM33= 60% de volumoso, 13,4% de silagem de graos de milho e 26,6% de farelo de soja e milho moido, e GMS= 60% de volumoso e 40% de farelo de soja e milho moido. A digestao e a digestibilidade da materia seca nao foram influenciadas pela inclusao de SGM na dieta. A dieta SGM66 aumentou a digestibilidade de materia seca no intestino em relacao a dieta GMS. Nao houve efeito da inclusao da silagem de graos na digestao e na digestibilidade das fracoes fibra em detergente acido e fibra em detergente neutro da racao, bem como no fluxo ruminal e intestinal do amido. A SGM66 melhorou a digestibilidade total da proteina bruta, mas nao mostrou efeito sobre a digestibilidade total da materia seca, da fibra e do amido e sobre o ambiente ruminal no que se refere a acidez e a concentracao de amonia.

Calorimetry, chemical composition and in vitro digestibility of sugarcane treated with calcium hydroxide

Abstract. Sugarcane is a source of roughage in animal feeding. It presents high production per unit of cultivated area, relatively easy cultivation and low cost of production per hectare, and better quality and a high dry matter (DM) yield in periods when forage is scarce. This study aimed to evaluate the effect of increasing levels of calcium hydroxide (Ca(OH)2) in sugarcane forage on chemical composition, in vitro digestibility values of DM, neutral detergentfibre (NDF) and acid detergent fibre (ADF), and kinetics of thermal decomposition processes of weight loss and heat flow. Sugarcane was collected close to the ground and 50-kg heaps of the fresh material were formed and mixed with four doses of Ca(OH)2 (0, 8, 16 and 24u2009g kg–1 sugarcane). Concentrations of NDF and ADF decreased linearly with increasing amount of Ca(OH)2, whereas concentration of hemicellulose increased linearly. In vitro digestibilities of DM, NDF and ADF were enhanced in a quadratic manner with increasing amounts of Ca(OH)2. The release of heat, measured by ΔH, increased linearly with increased Ca(OH)2 levels, likely due to enhanced digestibility of the fibre components. Weight loss decreased linearly between 272.2°C and 397.7°C with increased amounts of Ca(OH)2 added to sugarcane, likely due to changes in cellulose structure, which became denser and thermodynamically more stable than native cellulose following the alkaline treatment. Calcium hydroxide changed chemical composition and digestibility of the fibrous fraction of sugarcane, resulting in better nutritional value. The greatest release of heat and highest in vitro digestibility of fibre were observed when adding 15.2u2009g Ca(OH)2 kg–1 sugarcane; therefore, this dose is recommended to enhance the nutritive value of sugarcane as ruminant feed.

Typification of Factors Related to Milk Production and Its Impact on the Sanitary Quality of Milk

Aiming at identifying and characterizing the dairy production systems regarding the hygienic and sanitary practices in milking on the sanitary quality of milk, 32 properties were analyzed through the data collection by means of a semi-structured questionnaire. The collected data were analyzed by multivariate statistical analysis, using the Principal Component Analysis (PCA) and analysis of Ascending Hierarchical Classification Cluster (CHA). Firstly, a cluster analysis was used for forming groups of variables. Through the groups formed was sought to obtain the explanatory variables through the PCA. Three PCA were obtained, which were named according to the variables of greatest effect in the analysis. The groups were called PCA-1: Equipment and contamination; PCA-2: Milking Technology; PCA-3: Scale of production. These results enabled the representation of the different characteristics of the production systems through cluster analysis, where for each PCA was performed a Cluster analysis, always with five groups of dairy production systems being formed with similar characteristics within each group. The formation of the groups enabled to identify that the performance of techniques and hygienic-sanitary managements of milking is more related to the age and producer’s education, linked to time in the dairy business.