Glucose Metabolism in Steers Receiving High Fibre Diets and Glucose Infusion Into Abomasum

ABSTRACT: Glucose has been the subject of a number of studies due to as important role in ruminant metabolism. Nevertheless, there is paucity in the literature dealing with glucose metabolism when ruminants are offerred a low-quality roughages_ Eight Brahman steers approximately two years old and weighing 238 ± 23 kg were alloted randomly into an individual metabolism cage. Each steer received barley straw ad lib., 151) gld mineral mix and 75 g/d urea which was infused eontmously into the rumen. In addition to that, two steers were infused continously per abomasum with 1500 ml water/headid, whilst the remainders were infiised with 50, 100, 150, 200, 250 and 300 g/1500 mi/d anhydrous glucose during which die folloNving parameters were observed 7 feed consumption, rumen metabolites, nitrogen balance (NB). and metabolism of glucose. The last parameter was studied using a radio isotope technique. The results showed that aboniasal infusion of glucose significantly improved (130.01) the consumption of dry matter and organic matter as well as NB. The latter was associated with a significant reduction of urinary N excretion suggesting that there was a competition of glucose requirement on the expense of amino acid catabolism. There was no significant alteration (P>0. I) on the rumen metabolites attributable. to glucose infusion. Pool size of glucose was not altered by infusion but glucose entry rate (GER) and T 112 were linearly increased as the level of glucose infusion increased. The implication of this study is discussed in relation to practical app[icatiois with particular el nialiasis given to enhancement of niminant productivity on low-quality roughage. Key Words: Glucose. Metabolism, Barley Straw, Nitrogen Balanc