The Effect of Viral Infection under Various Mucociliary Transport Rates in the Non-Anesthetized Chicken

Abstract

The effects of viral infection following nasal mucociliary impairment in the nonanesthetized chicken were investigated by measuring the mucociliary transport rate under physiological conditions. Mucociliary transport rates in chickens’ postnasal fossa were measured by using a video monitor system connected to an otomicroscope, with direct vision through the palatine cleft. The chick was positioned in a specially designed plastic holder with a mouth opener. Changes of the mucociliary transport rates were induced by mechanical stimulation, dehydration, and 20% cocaine. The mucociliary transport rate was accelerated on the postnasal fossa adjacent to the mechanically stimulated side of the palatine cleft. Dehydration for 96 hours produced a progressive deceleration of the mucociliary transport rate. Topical application of 20% cocaine into the postnasal fossa caused ciliary paralysis within 5 minutes that continued for more than 1 hour. The topical inoculation of the Newcastle disease virus into the postnasal fossa induced significant deceleration of the mucociliary transport rate after 4 days. We studied the effect of mucociliary transport rates arising from topical inoculation of the Newcastle disease virus after inducing mucociliary dysfunction by mechanical stimulation, dehydration, and the application of 20% cocaine. Mucociliary transport rates in the dehydration and cocaine groups decelerated significantly 4, 7, 10, and 13 days after the inoculation compared with that before the inoculation. No decrease was seen in the mechanical stimulated group. Additionally, mucociliary transport rates at 10 and 13 days after inoculation were significantly decelerated in the dehydrated and 20% cocaine groups compared with that in the normal control group. These results suggest that the deceleration of the mucociliary transport rate may increase and prolong the severity of a viral infection.