Glucose tolerance test during abomaso-duodenal electromyography in three cows operated for left displaced abomasum.

The objective of the study was to analyze glucose metabolism and abomasal myoelectrical activity during an intravenous glucose tolerance test in cows operated for LDA. Three dairy cows, at the onset of lactation, suffering from left displaced abomasum were selected from the animals presented at the clinic. During surgical therapy, one pair of electrodes was placed in the smooth muscle of the abomasal body, the pars pylorica and the duodenum respectively. The animals were subjected to electromyography on five occasions during hospital admittance (Days 1, 2, 3, 5 and 7 post-operative); their insulin, glucagon, glucose, beta-hydroxybutyrate and NEFA levels were then measured. Two days after surgery, the animals were subjected to an intravenous glucose load (300 g glucose in 30 min) during abomaso-duodenal electromyography. The findings indicate that the three animals had glucose metabolism disorders during hospitalization. The abomaso-duodenal myoelectric activity of Cows 1 and 3 was lower than in Cow 2. During the glucose load, the analysis of hormones and metabolites showed that there were different degrees of reactivity and that myoelectric activity differed in the 3 cows. The results of the study suggest that despite the surgical reposition of the abomasum, disorders of abomasal motility persist in different degrees in cows operated for LDA and could be influenced by glucose administrations.