This page contains a Flash digital edition of a book.
ileal digesta samples from broilers fed a corn-SBM based diet without or with a pectinase containing product were also visualized using light microscopy. The resulting microscopy pictures showed that the digesta samples from animals fed the enzyme supplemented diet gave a very weak light pink signal compared to the samples from animals fed the diet without enzyme. This clearly indicates that the pectin degrading enzymes both survived the harsh conditions of the digestive tract and that they were active in degrading the SBM pectin components inside the gastro-intestinal tract.

Summary This work shows that microscopy can be used as a powerful tool to study the cell wall architecture of feed ingredients and the enzymatic effects in cell wall degradation, and serves as a useful complement to normal wet chemistry methods used for studying enzyme effects on feed raw materials in vitro and in vivo. By improving our knowledge in this area, the microscopy techniques described have the potential to further enhance our use of enzymes to improve nutrient digestibility in the animal and deliver further benefits to cost effective performance.

References Józefiak, D., Ptak, A., Kaczmarek, S., Mackowiak, P., Sassek, M., Slominski, B.A., 2010. Multi-carbohydrase and phytase supplementation improves growth performance and liver insulin rece tor sensitivity in broiler chickens fed diets containing full-fat rapeseed. Poult. Sci. 89, 1939–1946. Jia, W., Mikulski, D., Rogiewicz, A., Zdunczyk, Z., Jankowski, J., Slominski,

B.A., 2012. Low-fiber canola. Part 2. Nutritive value of the meal. J. Agric. Food Chem. 60, 12231–12237. Meng, X., Slominski, B.A., 2005. Nutritive values of corn, soybean meal, canola meal and peas for broiler chickens as affected by a multi- carbohydrase preparation of cell wall degrading enzymes. Poult. Sci. 84, 1242–1251. Meng, X., Slominski, B.A., Nyachoti, C.M., Campbell, L.D., Guenter, W., 2005. Degradation of cell wall polysaccharides by combinations of carbohydrase enzymes and their effect on nutrient utilisation and broiler chicken performance. Poult. Sci. 84, 37–47. Pedersen, N.R., Ravn, J.L., Pettersson, D. 2017. A multienzyme NSP product solubilises and degrades NSP structures in canola and mediates protein solubilisation and degradation in vitro. Animal Feed Science and Technology 234. Pettersson, D., Pontoppidan, K., 2013. Soybean meal and the potential for upgrading its feeding value by enzyme supplementation. In: El-Shemy, H.A. (Ed.), Soybean – Bio-Active Compounds, pp. 287–307. http://www. Ravn, J.L., Martens, H.J., Pettersson, D., Pedersen, Pedersen, N.R., 2015. Enzymatic solubilisation and degradation of soybean fibre demonstrated by viscosity, fibre analysis and microscopy. J. Agric. Sci. 7, 1–13. Sauvant, D., Perez-M, J., Tran, G., 2004. Tables of composition and nutritional value of feed materials. World agricultural production. Circular series WAP 9-16, INRA editions. Wageningen Publishers USDA 2016, pp. 9–16. Slominski, B.A., 2011. Recent advances in research on enzymes for poultry. Poult. Sci. 90, 2013–2023. Slominski, B.A., Jia, W., Rogiewicz, A., Nyachoti, C.M., Hickling, D., 2012. Low-Fiber canola. Part 1. Chemical and nutritive composition of the meal. J. Agric. Food Chem. 60, 12225–12230.

Protein for Dairy Cows: How Low is Achievable? Long term effects of reduced protein supply

By C K Reynolds, A. L. Thomson, A. K. Jones, and L. A. Crompton. Centre for Dairy Research, School of Agriculture, Policy and Development, University of Reading

Background Dietary protein is used inefficiently for milk protein production by dairy cows, with numerous studies and meta-analyses of published data reporting that approximately 75% or more of dietary N intake is excreted in manure (Mills et al., 2009; Olmos-Colmenero and Broderick, 2006). Nitrogen excreted in urine and faeces can be used as fertilizer, but depending on how it is managed substantial amounts of manure N is lost as ammonia (in particular urinary urea N), nitrate (which contributes to environmental eutrophication), or nitrous oxide (a potent greenhouse gas). Losses of nitrogen also occur when inorganic N is used as fertilizer and therefore there is benefit in using legumes to minimize N fertilizer requirements in ruminant production systems. Because of concerns regarding these environmental losses


there is considerable interest in improving the efficiency of dietary N utilization in dairy production systems. By improving diet N use efficiency (NUE) for milk protein production total loss of N to the environment and the reliance on purchased protein supplements could be reduced. For lactating dairy cows NUE is affected by a variety of dietary factors that determine metabolizable protein (MP) supply relative to requirement, such as energy and N interactions in the rumen and post-absorptive effects of absorbed energy substrates on the efficiency of absorbed amino acid utilization. In addition, reducing diet crude protein (CP) concentration and thus N intake (NI) consistently increases NUE. With increasing NI, N excretion in milk, faeces, and urine increase, but the rate of increase is least for milk and greatest for urine, thus NUE decreases. In practice, dietary protein

Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68