ABSTRACT The attempt to face the limitations of wood-based materials, especially concerning the relationship with water, is still a considerable gap in research on this subject. The present work proposes the accomplishment of thermal treatment in fiberboard-type hardboard, using different temperatures and times, to evaluate the effect on the physical-mechanical properties. The parameters of the heat treatment were temperatures of 120 and 160 °C and times of 20 and 40 min. The hardboards were individually heat treated in a kiln. The characterization was performed from physical tests such as bulk density, moisture content, water absorption (2 and 24 h), thickness swelling (2 and 24 h); and mechanical properties of flexural strength. The treatment with a temperature of 160 °C for 40 min showed the lowest values of water absorption in 24 h (34%). Thickness swelling was lower compared to control, for all the treatments applied. Regarding flexural strength, the treatment that adopted the 160 °C for 20 min showed the highest MOR value (26.3 MPa). In general, the performance of heat treatments positively influenced the physical and mechanical properties of the hardboards, being an interesting alternative in the development of products for applications in internal environments.

Abstract: This study aimed to evaluate nutrient intake and digestibility, performance and economic viability of steers during the rearing phase in Brachiaria brizantha cultivar Marandu graze and in feedlot. Were used fifty crossbred steers in the rearing phase, with a mean weight of 275 ± 8.18 kg, distributed in a completely randomized design with ten replications per treatments: Mineral supplementation, nitrogen supplementation, Concentrate supplementation in the order of 1 and 2 g/kg body weight and total feedlot. The total dry matter intake and body weight showed a difference (P<0.05) for animals in feedlot. Crude protein, ether extract, neutral detergent fiber corrected for ashes and protein, non-fibrous carbohydrates, total digestible nutrients showed differences for the animals that received mineral supplementation in comparison to the other managements adopted. The same performance was observed for animals in feedlot. The digestibility coefficients of dry matter, crude protein, ether extract, non-fibrous carbohydrates and total digestible nutrients showed a difference (P<0.05) for the animals that received mineral supplementation, in comparison to the other managements adopted. (P<0.05). The mean daily gain was lower (P<0.05) for animals receiving mineral supplementation. The gross margin was higher (P<0.05) for animals handled in feedlot. Considering the obtained results, it was possible to observe that the animals kept in graze with good availability of dry matter presented satisfactory performance. It is feasible to confine the animals in rearing, since it shortens the production cycle, generating favorable economic results.

Resumen Este estudio buscó evaluar la ingesta y digestibilidad de nutrientes, el rendimiento y la viabilidad económica de novillos alimentados con Brachiaria brizantha cultivar Marandú y criados bajo sistemas de pastoreo y engorda en corral. Se utilizaron 50 novillos cruzados en fase de crecimiento con un peso medio de 275 ± 8.18 kg. Los novillos se distribuyeron en un diseño completamente al azar con 10 repeticiones por tratamiento: suplementación mineral, suplementación de nitrógeno, suplementación del concentrado en el orden de 1 y 2 g/kg de peso corporal y engorda total en corral total. El consumo de materia seca total y el peso corporal fueron significativamente diferentes (P<0.05) para los animales en engorde en corral. La proteína cruda, el extracto etéreo, la fibra detergente neutra corregida para cenizas y proteína, los carbohidratos no fibrosos y los nutrientes digestibles totales fueron diferentes en los animales suplementados con minerales en comparación con los otros tratamientos. El mismo rendimiento se observó en los animales en engorde. Los coeficientes de digestibilidad de materia seca, proteína cruda, extracto etéreo, carbohidratos no fibrosos y nutrientes digestibles totales en los animales suplementados con minerales fueron significativamente diferentes (P<0.05) a los otros tratamientos. (P<0.05). La ganancia diaria promedio fue menor (P<0.05) en los animales suplementados con animales. El mayor margen bruto (P<0.05) se observó en los animales bajo engorde en corral. Los resultados obtenidos en este estudio indican que los animales en pastoreo con una buena disponibilidad de materia seca presentan un rendimiento satisfactorio. Es factible confinar a los animales en fase de cría debido a que se acorta el ciclo de producción y se obtienen resultados económicos favorables.

O objetivo foi avaliar a variação anual das características morfológicas de pelame de vacas mestiças Holandesas x Gir, ½ e ¾ de Holandês da região de Salinas - Minas Gerais. As características morfológicas do pelame estudadas foram: espessura da capa, comprimento médio dos pelos e densidade numérica. A coleta de pelos foi realizada em cada estação climática (primavera, verão, outono e inverno). A caracterização climática das estações do ano foram obtidas a partir dos dados disponibilizados pelo Instituto Nacional de Meteorologia (Inmet). Os dados para as características morfológicas do pelame foram submetidos à análise de variância seguindo um delineamento inteiramente casualizado em esquema fatorial (dois graus de sangue e quatros estações climáticas). Encontrou-se efeito de estação do ano, demonstrando que o pelame das vacas mestiças se ajusta com as variáveis ambientais. E o comprimento e número de pelos/cm² apresentaram-se maiores nos animais ¾ Holandês. Conclui-se que os animais mestiços estudados possuem pelame curto, pouco denso e bem assentado, principalmente no verão. Os animais ½ Holandês apresentaram pelame menos denso e mais curto que os animais ¾ Holandês.

The objective was to evaluate annual variation the morphological characteristics of the hair coat of the cows crossbred Holstein x Gir, ½ and ¾ of the Holstein in Salinas -Minas Gerais region. The morphological characteristics of the hair coat were: coat thickness, hair length, number of hair/cm². Hair coat samples were held in each season (spring, summer, autumn and winter). The climatic characterization of the seasons was obtained from data provided by National Institute of Meteorology (INMET). Data for hair coat characteristics were subjected to variance analysis of according to a completely randomized factorial design (two degrees of blood and four seasons). The season effect showed that haircoat of the crossbred cows adjusted with environmental variables. And the length and number of hair/cm² were higher in animals ¾ Holstein. It was concluded that crossbred animals have short hair coat, very dense and well seated, especially in summer. ½ Holstein showed less dense hair coat and shorter than ¾ Holstein.