Effect of Age on Pharyngeal Pumping in Two Species of Free-Living Nematodes

Pharynx is a neuromuscular pump present at the anterior end of the alimentary tract. Feeding rate as well as the precise timing of pharyngeal movements, is required for efficient feeding and for survival in nature. Described here are the age-related changes in pharyngeal behaviour of two rhabditid nematodes viz., Metarhabditis andrassyna and Teratorhabditis palmarum. In both the species the average pharyngeal pulsation were more in the presence of bacteria than in its absence. Pulsation rates declined with age in both species in both the conditions. Deterioration in the structure of the basal bulb was also observed.