Incorporation of endogenous urea nitrogen into the amino acids of bacterial protein in the rumen of goats fed diets with various protein levels

Journal Title: Journal of Animal and Feed Sciences - Year 2013, Vol 22, Issue 4

Abstract

The aim of the study was to investigate the effect of different levels of protein in a diet on the incorporation of endogenous urea nitrogen (EUN) into individual amino acids (AA) of the ruminal bacteria of goats fed a low- (LP), medium- (MP), or high-protein diet (HP) in a 3 × 3 Latin square design. Three Alpine goats of about 35 kg body weight fitted with cannula into the rumen and catheter into the jugular vein were fed three isoenergetic diets containing 11% (LP), 13% (MP), or 16% (HP) crude protein in dry matter. The goats were infused for 6 days continuously with an 15N urea solution into the jugular vein. Ruminal bacteria were hydrolysed with 6M HCl. Next, butyl derivatives of free bacterial AA were obtained using HCl in butanol, then N-acylated using trifluoroacetic acid anhydride and analysed by gas chromatography using a mass-selective detector. The concentration of urea in plasma was 178, 356 and 667 mg · l–1 in goats from groups LP, MP and HP, respectively. 15N-excess during the infusion of labelled urea was significantly higher (P < 0.05) in the vast majority of AA of ruminal bacteria from goats fed the LP diet in comparison with goats fed the HP diet. Therefore, the level of protein in the diets affects the incorporation of EUN into bacterial AA. With the LP diet, EUN was incorporated mostly into glutamic acid, isoleucine and arginine, while in the case of the HP diet, into glutamic acid and arginine, as well as methionine. Regardless of the level of nitrogen in the diets, the incorporation of 15N into proline was very low. Irrespective of the dietary nitrogen level, EUN appears to be predominantly used for synthesis of glutamic acid in ruminal bacteria.

Authors and Affiliations

J. P. Michalski, J. Kowalczyk, M. Czauderna, W. Litwin

Keywords

Related Articles

Performance, egg quality, blood profile, immune function, and antioxidant enzyme activities in laying hens fed diets with thyme powder

This study evaluated the effect of thyme (Thymus vulgaris L.) on productive performance, egg quality, blood profile, immune function and antioxidant enzyme activity in laying hens. A total of 96 thirty-six-week-old layin...

The influence of hydrolyzed and non-hydrolyzed linden inflorescence (Tilia cordata) extract on metabolic and transcriptomic profile in rat liver

The extract from linden inflorescence is one of the pharmacognostic resources which properties are associated with the presence of flavonoids (mainly: quercetin, aempferol, acacetin glycosides and tiliroside). Flavonoids...

Genetic relationships among time of egg formation, clutch traits and traditional selection traits in laying hens

In a population of Rhode Island White hens heritability of egg formation, clutch characters and traditional selection traits as well as the genetic and phenotypic correlations between them were estimated via multitrait a...

The development of the small intestine of piglets - chosen aspects

The development of the gastrointestinal tract is a very sophisticated process, which starts during prenatal life and continues after birth. Diet is the most important factor modulating structure and functions of the inte...

Incorporation of endogenous urea nitrogen into amino acids of milk in goats fed diets with various protein levels

The aim of the study was to estimate how much endogenous urea nitrogen (EUN) was incorporated into various amino acids of milk protein when goats were fed low (LP), medium (MP), or high protein (HP) diets in a 3 × 3 Lati...

Download PDF file
  • EP ID EP73001
  • DOI -
  • Views 132
  • Downloads 0

How To Cite

J. P. Michalski, J. Kowalczyk, M. Czauderna, W. Litwin (2013). Incorporation of endogenous urea nitrogen into the amino acids of bacterial protein in the rumen of goats fed diets with various protein levels. Journal of Animal and Feed Sciences, 22(4), 311-315. https://europub.co.uk/articles/-A-73001