Abstract: The objective of this research was to evaluate the effect of adding protected protease to low-amino acids (AA) diets on the growth performance of barrows. Three decreasing levels of AA (protein levels), with or without the addition of protease were fed to 48 hybrid barrows (27.42±3.48 kg initial body weight). The experimental design was a completely randomised with a factorial arrangement of treatments. An analysis of variance was performed with GLM of SAS and the means comparison was performed with Tukey test (P<0.05). The productive performance was not affected by addition of proteases in the diet at the three stages (P>0.05). Only in growing barrows, the interaction of standard protein diet and protease reduced backfat thickness (P<0.05). Protein level in finishing I barrows did not affect (P>0.05) growth performance variables. Low-protein diets increased (P<0.05) average daily gain, final body weight and fat-free lean gain in growing and finishing II barrows. Concentration of urea in plasma decreased with the reduction of CP and increased with the addition of protease (P<0.05) at the three stages. In conclusion, low protein diets improved or maintained growth performance variables and reduced the plasma urea nitrogen, whereas supplementation with protease did not show any effect on productive performance.

No presente trabalho, considera-se o estudo do potencial de utilização de resíduos da casca de amendoim, com o intuito de agregar valor a este material, por meio da fabricação de painéis de partículas aglomeradas com resina ureia-formaldeído, prensados à temperatura de 100 ºC. A qualidade dos painéis foi avaliada com base nas prescrições do documento normativo ASTM D 1037:2006 por meio de ensaios físico-mecânicos de densidade, inchamento em espessura, absorção de água e flexão estática. Os painéis avaliados apresentaram densidade média variando de 0,69 a 0,83 g cm-3, MOR 4,37 a 5,34 MPa e MOE 590 a 700 MPa, para painéis com e sem tratamento preservativo. É possível afirmar, baseando-se no documento normativo ANSI A208.1:1993, que o material apresenta potencial para utilização em ambientes internos, como revestimento superficial de residências, construções agrícolas, setor moveleiro e decorativo. Recomenda-se a intervenção no processo de fabricação do painel, para melhorar as propriedades mecânicas e possibilitar o uso estrutural do material.

In this study, the potential use of residues of peanut husks was verified, in order to add value to these materials through the manufacture of panels of particleboards. For this procedure, it was used urea-formaldehyde resin and the panels were mechanical pressed at a temperature of 100 ºC. The quality of the panels was evaluated based on the prescriptions of the normative document ASTM D 1037:2006, through physical and mechanical tests of characteristics, such as: density, swelling in thickness, water absorption and static bending. The panels evaluated showed bulk density varying between 0,69 a 0,83 g cm-3, MOR and MOE between 4,37 - 5,34 MPa and 590 - 700 MPa respectively, for panels with and without preservative treatment. It is possible to claim, based in the normative document ANSI A208.1:1993, that the material presents a potential for use in internal areas as superficial covering of residential buildings, agricultural buildings, furniture and decorative sectors. Intervention in the board production process is recommended, in order to improve the mechanical properties of the material and enable its structural use.