Untreated and formaldehyde-treated urea as nitrogen sources for young growing bulls

Authors

• Jouko Setälä Department of Animal Husbandry, University of Helsinki, 00710 Helsinki 71, Finland
• Liisa Syrjälä-Qvist Department of Animal Husbandry, University of Helsinki, 00710 Helsinki 71, Finland
• Pentti Aspila Department of Animal Husbandry, University of Helsinki, 00710 Helsinki 71, Finland

DOI: https://doi.org/10.23986/afsci.72089

Abstract

Untreated urea and urea treated with 1.5 % formaldehyde were compared as nitrogen sources for young growing bulls. The experiment was performed with 12 individually fed animals, eight of which were Friesians and four Finnish Ayrshires, and the average age of the animals at the beginning of the experiment was about 3.5 months. After a standardization period of two weeks, the animals were divided into two groups with similar distributions by daily gain, feed utilization, liveweight and age. During the following transition period of one week the feeding of the animals was changed to the experimental diets of the 24-week test period. The feeding was based on NaOH-treated barley straw and a mixture of barley, oats and molassed beet pulp, and planned for a daily gain of 1000 grams/animal. During the standardization period the animals received 2.9 % untreated urea in the concentrate, and soybean meal was also used to bring the feeding into agreement with the standards chosen. During the test period the animals received untreated or treated urea and their contributed about 35—40 % of their DCP requirements. There were no significant differences between the groups in daily gain, feed utilization or slaughter results. Nor did the two groups show any significant differences in plasma urea, albumin and total proteins. The plasma concentrations of aspartate aminotransferase, alanine amino transferase and creatinine did not differ significantly between the groups.