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 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.

O setor de nutrição e produção animal busca constantemente por fontes de alimentos que oportunizem os fatores custo e benefício para a elaboração de formulação de dietas. A mandioca é um alimento mundialmente cultivado e apresenta diversos subprodutos ao decorrer de sua produção com excelente característica energética, que podem ser utilizados, como é o caso de sua parte aérea, em substituição a silagem de milho na dieta de vacas leiteiras. Porém, sua inclusão na dieta de vacas em lactação deve ser realizada com cautela, necessitando de estudos que viabilizem o processamento e as formulações em quantidades aceitáveis, tendo em vista seus fatores anti nutricionais.

The objective was to evaluate the microbiological quality of water and milk from agroecological and conventional properties in western Paraná. The collections were carried out in 20 conventional properties in the municipality of Santa Helena - PR, and in 27 agroecological bases and in Diamante d'Oeste and Ramilândia - PR. Milk collections were carried out in different production systems and seasons. Were analyzed the contamination of thermotolerant coliforms (ThermC), total coliforms (TC), enterobacteria, aerobic mesophiles (AM), determination of chemical composition, somatic cell count (SCC) and total bacterial count (TBC). There was no difference in milk composition between summer production systems. In relation to SCC during the winter, 44.4% and 55.0% of the properties presented values ​​above 600 thousand cells mL^-1, in the agroecological and conventional systems, respectively. In both seasons, most of the agroecological properties are above 600 thousand CFU mL^-1 of TBC. In both production systems and seasons, the AM values ​​were lower than those allowed by NI76, and there was no difference for enterobacteria in milk. The count of milk TC in winter was similar between the two production systems. For the water samples for cleaning the milking equipment, the TC and ThermC values were higher in the agroecological system. The use of management practices is recommended in order to reduce the SCC and TBC values ​​of milk produced in the western of Paraná to conform to the values required by NI76.

The purpose of this paper was to study the storage of the residue from the extraction of cassava starch without the use of storage technologies, through chemical evaluation, pH values, temperature, development of microorganisms and mycotoxins. A randomized block design was used with eight treatments (different storage periods: 0, 3, 6, 9, 12, 15, 18 and 21 days) and five replications. There was a significant difference for DM content, as a function of days in storage. The chemical composition of the residue from the extraction of cassava starch did not changed throughout the storage period. A negative linear effect was obtained for the pH values, which decreased with days in storage. There was significance of the storage period only for the fungus and yeast population, which increased up to 17 days of storage, with subsequent reduction. Mycotoxins were detected in the residue from the extraction of cassava starch. Despite it did not showed changes in the chemical composition the storage of residue from the extraction of cassava starch for 21 days proved to be an inefficient preservation process, due to the development of molds and mycotoxins