RESUMO
This study was to investigate the effect of dietary supplementation with xylanase and protease on growth performance, digesta viscosity, apparent ileal digestibility (AID) of nutrients, and gut health in nursery pigs. Forty-eight pigs (24 barrows and 24 gilts at 21 d of age with 7.2 ± 0.4 kg BW) were randomly allotted to 4 dietary treatments (2 × 2 factorial arrangement) in a randomized complete block design and fed in 2 phases (phase 1 for 10 d and phase 2 for 14 d). Factors were xylanase (0 or 45,000 XU/kg) and protease (0 or 300,000 U/kg). Feed intake and BW gain were measured on d 10 and 24. Titanium dioxide (0.25%) was added to all diets as an indigestible external marker from d 20 to 24. On d 24, all pigs were euthanized to obtain jejunal and ileal digesta to measure viscosity and apparent ileal digestibility. The jejunal mucosa was collected to measure immune and oxidative stress status. Jejunal tissues were used to measure morphology and crypt cells proliferation. In phase 2, xylanase increased (P < 0.05) the average daily gain (ADG) which was further increased (P < 0.05) when combined with protease. Overall, combinational use of xylanase and protease increased (P < 0.05) ADG compared with the use of xylanase or protease alone, whereas protease improved (P < 0.05) feed efficiency. In jejunum, xylanase reduced (P < 0.05) viscosity of digesta, mucosal malondialdehyde (MDA), crypt depth and crypt cells proliferation, and protease increased (P < 0.05) villus height, and decreased (P < 0.05) crypt depth and crypt cells proliferation. Collectively, xylanase improved growth performance, digesta viscosity, and oxidative stress, whereas protease improved feed efficiency and gut morphology. The combinational use of xylanase and protease enhanced growth performance of newly weaned pigs.
RESUMO
Functional protein microarrays promise new approaches to address longstanding challenges in drug discovery and development, with applications ranging from target identification to clinical trial design. However, their widespread adoption will be contingent upon a robust ability to develop and manufacture arrays in support of these applications. This review will address the major areas of relevance to the development of functional protein microarrays; protein content, surface chemistry, manufacture and assay development. Successful development will empower multiple drug research applications, help fill future HTS pipelines and guide next generation combinatorial chemistry efforts.