The effect of the plasma glucose level on the abomasal function in dairy cows.

Abstract

We have studied the effect of plasma glucose level on the abomasal outflow rate of fluid using a hyperinsulinemic glucose clamp technique in dairy cows. Four nonpregnant, nonlactating cows were subjected to one of the following treatments: hyperinsulinemic normoglycemic clamp; hyperinsulinemic hypoglycemic clamp; hyperinsulinemic hyperglycemic clamp; or, as a control, an intravenous infusion of .9% sodium chloride in a Latin square design. The cows were previously fitted with a permanent fistula in the abomasum and the outflow rate of abomasal fluid was determined using Co-EDTA as a marker assuming that the outflow followed first-order kinetics. The abomasal pH was also registered. Insulin was infused continuously through a jugular catheter at a rate of 4.8 mU. kg(-1)min(-1) for 2.5 h in the three clamp treatments. A glucose solution was infused through the catheter at a variable rate to achieve a circulating concentration, near the preinfusion glucose level (approximately 4.1 mmol/L), 2 mmol/L below the preinfusion level, and 2 mmol/L above the preinfusion level for the three hyperinsulinemic treatments, respectively. There was a significant effect of treatment on the rate of abomasal outflow (P < .001). The rate of abomasal outflow was highest for the control treatment (7.8%/min). The slowest outflow was observed in the hyperglycemic cows (3.40%/min). The hypoglycemic and normoglycemic cows showed intermediate rates (6.0%/min and 5.2%/min, respectively). The rate of outflow for the hyperglycemic cows was significantly lower than for all the other treatments (P < .01). Abomasal pH was affected by treatment (P < .05). The highest pH was observed in the hyperglycemic cows (pH 2.3). The values for the other three treatments ranged from pH 1.9 to 2.0. These results show that hyperglycemia reduced the rate of outflow and increased the pH of abomasal fluid in dairy cows. An elevated plasma glucose level thus can be considered as a potential risk factor in the pathogenesis of left-displaced abomasum.

Left displacement of the abomasum in dairy cattle: recent developments in epidemiological and etiological aspects

“…A severe NEB has been regarded to result in an increased risk for DA [5,9,21,26,53]. Pathways mentioned are hypo-or hyperglycemic status, hyper-, or hypoinsulinemia in these cows [28].…”

“…Patients with a displaced abomasum however, have often an elevated glucose and insulin level in the blood circulation [12,30,46]. Holtenius et al report decreased abomasal motility in cows with elevated insulin, glucose, and glucagon levels as well as in cows with high insulin combined with low glucose levels [27,28]. The authors mention difficulties in interpreting the results since the levels of glucagon, glucose and insulin are dependent on each other and the blood levels exceed normal conditions.…”

“…The authors mention difficulties in interpreting the results since the levels of glucagon, glucose and insulin are dependent on each other and the blood levels exceed normal conditions. The effect of high glucose levels can be mediated by a decreased vagal tonus [18,28]. Van Winden et al found low levels of insulin and glucose in cows that later on developed DA [66].…”

Comparison of laparoscopic and traditional abomasal cannulation in sheep

“…Digestive tract fistulation was first used to study alimentary tract physiology in 1822. Cannulation of the abomasum has been used for abomasum examination (13) to obtain abomasal fluid (24), to measure abomasal emptying rate (14,28), for parasitological (26) and pharmacological studies (5), and for the treatment of abomasal ulceration (23).…”

Laparoscopic abomasal cannulation in sheep

“…There has been considerable interest in the cannulation of the abomasum in nutritional studies to obtain abomasal fluid for the measurement of the abomasal contents (Pearson et al 1981) and to determine the outflow rate of abomasal fluid for the further study of abomasal function (Holtenius et al 2000). The application of abomasal cannulation has also been described for the examination of the abomasum in follow-up studies in veterinary parasitology (Hertzberg et al 1994) and for the infusion of nutrients and drugs into the abomasum to reach high concentrations (Charles et al 1993;Vynckier and Debackere 1993).…”