Maria Luiza Fischer

This study evaluated the impact of bacterial inoculant and urea on the chemical composition of AGRI 002E forage sorghum silage over different storage periods. Four treatments were tested: control (WS), bacterial inoculant (SBI), urea (US) and both urea and bacterial inoculant (USBI), with samples evaluated after 0, 28, and 56 days of ensiling. Parameters analyzed included organic acid, soluble carbohydrates (SC), condensed tannins (CT), ammonia nitrogen (NH3-N) dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), acid detergent fiber (ADF), non-fibrous carbohydrates (NFC), lignin, in vitro digestibility (IVD), CP fractions, and total carbohydrate fractions. Results showed increased in DM, OM, total carbohydrates, NFC and digestibility over time, while CT, NDF, ADF, and SC decreased. Urea supplementation notably increased CP and IVDCP, and reduced fiber concentrations compared to the control and bacterial inoculant treatments. Silage stability was achieved after 28 days, but a 56-day period is recommended for optimal fermentation and quality. Urea alone improves digestibility and non-protein nitrogen availability, and combining it with bacterial inoculants may enhance aerobic stability.

Visando compreender a diversidade de práticas adotadas pelos sistemas de produção leiteira no manejo higiênico-sanitário e seus impactos nas características de composição do leite, foram realizadas 23 entrevistas semi-estruturadas com produtores, utilizando um questionário guia como instrumento principal. A análise das variáveis explicativas foi conduzida por meio da Análise de Componentes Principais (ACP), que permitiu identificar os principais fatores associados à composição e à qualidade do leite. O componente principal 1 (CP1) destacou-se pelas variáveis relacionadas aos componentes do leite, enquanto o componente principal 2 (CP2) foi caracterizado por indicadores de qualidade sanitária, como a contagem de microrganismos. Juntos, esses componentes explicaram 46,88% da variância total. Os resultados, analisados por meio de cluster, formaram cinco grupos distintos, que evidenciaram a relação entre deficiências nos procedimentos de higiene, limpeza e sanitização dos equipamentos de ordenha e a contaminação por microrganismos, comprometendo a qualidade nutricional, sanitária e, consequentemente, o valor comercial do leite produzido.

The objective of this work was to evaluate the effects of the use of additives on the ensiling of AGRI 002E sorghum (Sorghum bicolor), focusing on the chemical composition, loss, microbial profile, and fermentative stability of the fodder. Sorghum was harvested 111 days after sowing, chopped, and ensiled in PVC silos under different treatments, as follows: without additives (SS), with inoculant (SSI), with urea (SSU), and with urea and inoculant (SSUI). The silos were opened and analyzed at 1, 3, 7, 14, 28, and 56 days after ensiling. The inclusion of urea and bacterial inoculant did not significantly affect dry matter content, but influenced dry matter recovery and microbial population, reducing the presence of clostridia and fungi. Dry matter and gas losses were minimal, indicating an adequate fermentation. The additives contribute to a more stable fermentation and a better preservation of the ensiled material, particularly by reducing undesirable microbial populations.

The objective of this study was to evaluate the effect of inclusion of condensed tannins (CT) from black wattle (Acacia mearnsii) on feed intake, ruminal protozoa population, ruminal fermentation, and nutrient digestibility in Jersey steers. Five ruminally-cannulated steers were used in a 5 × 5 Latin square design, with five periods of 20 days each (14 days for diet adaptation and six days for sample collection per period). Treatments were composed of dietary inclusion levels of condensed tannins at 0, 5, 10, 15, and 20 g/kg of diet dry matter. Intakes of dry matter, organic matter, ether extract, crude protein, neutral detergent fiber, and total digestible nutrients were not affected by condensed tannins. The ruminal pH was reduced linearly with tannin levels. Ruminal ammonia nitrogen concentration was not affected by tannins. Tannins reduced the molar proportion of acetate and did not affect the ruminal protozoal population, which might be related to the low doses used. Digestibilities of dry matter, organic matter, and neutral detergent fiber were not altered; however, there was a linear reduction in crude protein digestibility. Based on these results, CT extracts from black wattle are not recommended for improving nutrient utilization in steers at the tested levels.

The objective of this study was to evaluate the nutritional quality of twenty-nine cultivars of sugarcane. The design was completely randomized, with twenty-nine treatments (cultivars) and three replicates. The evaluations were performed at 540 days after planting during the phenological stage of maturation of sugar cane. Stalk length, number of nodes per plant, internodes length and stalk diameter were evaluated. The stalk samples were crushed, pre-dried and ground for achievement of chemical analysis, carbohydrate fractionation and in vitro digestibility of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF). Data were analyzed by analysis of variance and posteriorly submitted to Scott-Knott test at 5% probability. Regarding biometric measurements the cultivars differed (P0.05) in the number of nodes as well as in the average internode length and stalk diameter. The content of DM, OM, protein, ether extract, NDF and acid detergent fiber showed differences between the cultivars evaluated (P<0.05). Carbohydrate fractionation also differed between cultivars (P <0.05), being that cultivars RB86 7515, RB92 806 and RB03 6091 presented high fraction of rapidly degradable carbohydrates. The highest values of in vitro digestibility of DM and OM occurred for cultivars RB86 7515, RB92 579 and RB03 6091 (P<0.05). Considering the variables analyzed, the cultivars RB03 6091, RB92 579 and RB86 7515 showed greater concentration of rapidly degradable carbohydrates and greater in vitro digestibility of DM and OM demonstrating potential for use in ruminant feeding.