Hospitalization disrupts the daily rhythm of tear production in cats.

Abstract

The exposure to constant light during the hospitalization was investigated to verify its influence on the daily rhythmicity of Schirmer tear test I (STT I) in the Felis catus. One group (HG-hospitalized group) was consisted of 10 owned-cats hospitalized to perform a sterilization procedure and was exposed to a 24/0 light/dark (L/D) cycle; the cat control group (CG) was consisted of 10 staff-owned cats living in an indoor environment (12/12 L/D cycle). The STT I values was performed at 4h intervals over a 48 h period (starting at 8:00 a.m. on Day 1 and finishing at 8:00 a.m. on Day 3) on the left (LE) and right (RE) eyes into two cat groups. A 35 x 5 mm commercial tear test strip was used to record tear production in millimeters wetting per minute (mm/min). Multivariate for repeated measure analysis of variance (ANOVA) showed a statistically significant effect of time. No difference was found between LE and RE tear production, and between the two experimental conditions. Robust daily rhythmicity was exhibited by the STT I in both eyes during the entire monitoring period in control cats and only during the Day 1 in hospitalized cats. These data are a starting point for evaluating the imbalance of ocular physiology observed in hospitalized cats. Further studies on larger sample size and exposing the animals to various hospitalization procedures are needed to establish whether these alterations are caused by hospitalization procedures or by the light/dark schedules.