Arginine: an indispensable amino acid for mature dogs.

There studies examined the effect of dietary arginine deficiency in the mature dog. Deletion of arginine from the diet resulted in a slight but significant loss of body weight. Severe episodes of emesis were observed in all experiments. Muscle tremors and frothing around the mouth were also observed in the experiments where the arginine-free diet was force fed. Increasing the amount of diet force-fed to mature dogs accentuated the symptoms of emesis, muscle tremors and frothing. Elevated plasma ammonia and orotate were detected in dogs fed an arginine-deficient diet. Urinary citric and orotic acid was also increased in mature dogs fed a diet devoid of arginine. Nitrogen balance was not significantly altered by deletion of arginine from the diet. Based on the occurrence of emesis, loss of body weight and alterations in intermediary metabolism, we concluded that the mature dog does require a dietary source of arginine. Dietary inclusions of 0.28% arginine prevented the symptoms of arginine deficiency.