Investigations on etiology and pathogenesis of abomasal displacement in adult cattle

heritability, fat:protein quotient, and motility disorders

Abstract

Heritability of abomasal displacement was estimated in 30 Friesian herds in Germany using similarity between mothers and daughters. Four-point correlation coefficients were calculated from quadrant squares. The h2 of abomasal displacement was estimated to be 0.24. Milk composition analysis was used to indicate an energy deficit in the diet (fat:protein ratio >1.4) and indicated that cows in 27 herds in which abomasal displacement occurred (case herds) had not received energy-rich carbohydrates in the diets unlike 27 herds in which abomasal displacement was not diagnosed (control herds). In herds where abomasal displacement occurred the high fat:protein ratio in the milk was found in the year before abomasal displacement was diagnosed, and was significantly higher than in the control herds. The fat:protein ratio also tended to be high in the month before abomasal displacement occurred. This indicates that herds in which abomasal displacement occurred received less energy-rich carbohydrates than herds in which displacement was not diagnosed. In vitro studies on muscle strips from the abomasal antrum of healthy cows and cows with abomasal displacement indicated that muscle activity was inhibited during abomasal displacement due to lack of cholinergic excitation and/or predominance of nitroxergic inhibition.