104 N metabolism in ruminants supplemented with post-ruminally delivered urea.

Practical aspects of urea and ammonia metabolism in ruminants

Nitrogen was recognized over 200 yr ago as an element essential for normal function of farm animals. During the first half of the 19th century, the roles of proteins and urea in N metabolism were discovered. By the middle of the 20th century, the substrates, products, and enzymes of the urea cycle were elucidated. Work since then has quantified dietary crude protein requirements for specific pr...

Urea metabolism in sulfate-deprived and sulfate-supplemented rats.

Dynamic Changes of Main Rumen Microflora and Ruminal Fermentation in Sheep Supplemented with Molasses-Urea

The digestion and utilization of roughage by sheep depends on rumen digestion. The aim of this study was to evaluate the microbe quantity and fermentative efficiency of rumen supplement with molasses-urea. This experiment was conducted in 2014, eight sheep were selected and divided into two groups (a control group and a treatment group), and only the treatment group animals were supplied with m...

The Utilization of Urea-supplemented Roughages

In many parts of the world, poor quality roughages low in nitrogen are the only food available to the grazing ruminant. Experiments have shown that under some conditions, still not clearly defined, urea can improve both the digestion and intake of these roughages, and also the nitrogen status of the animal. However, there are reports from both the laboratory and the field, which indicate that u...

Urea Metabolism in Sheep

The rate at which urea enters the body pool of urea in sheep was investigated using isotope dilution techniques. Both single injection and constant infusion of carbon-14 urea were used. Urea excretion rates were calculated by measuring the urea in urine collected from a catheter in the bladder. Urea entry and excretion rates were measured in sheep fed rations containing 3.5, 9, 17 and 27% crude...