Abstract
Purpose :
The use of Optokinetic Response (OKR) as a quantitative measurement of visual acuity for adult zebrafish in the last decade continues to be increasingly popular. In previous studies, evidence suggests that visual acuity in zebrafish peaks around 15 months of age and plateaus thereafter. To expand this information and comprehend the viability of zebrafish in vision research, we examined six years of OKR visual acuity data completed in our lab to generate a baseline for visual acuity for adult zebrafish.
Methods :
We analyzed 18 different OKR experiments from the last six years (2011-2017). Each data set was assessed and combined using Microsoft Excel. Fish ID, genotype, birthdate, date of OKR, and visual acuity in cycles per degree (cpd) values were calculated and compiled. Wild-type consisted mostly of AB fish with some TU or TL data points. Mutant cpd data came from bugeye/Lrp2, Ruby, and Casper. Data sets missing birthdates were estimated based off breeding schedule logs and fish ID numbers. In experimental data that recorded only absolute spatial frequency (asf), cpd values were calculated using the mean of average eye distances. Data was analyzed using Excel and SPSS.
Results :
More than 483 zebrafish OKR measurements were observed: n=336 for wild-type, n=107 for bugeye, n=21 for Ruby, n=19 for Casper. The data reveals wild-type cpd values having the least variance at 5 months, 25-30 months and after 40 months of age. The greatest amount of variance in cpd values occur around 10 months and 34-39 months of age. Visual acuity initially plateaus around 12-15 months, but rises again around 20 months where it remains rather constant for years. In comparison to wildtype, bugeye zebrafishes had an increase in variance of cpd as it aged. Ruby zebrafish in comparison to wildtype had an overall lower cpd throughout their life span whereas Casper zebrafish acuities were not dissimilar to wildtype values.
Conclusions :
We were able to observe the visual acuity throughout the lifespan of wildtype and mutant zebrafishes ranging from 5 months to 90 months of age. The data reveals a gradual increase in wild-type visual acuity from 5 to 20 months of age and approximately plateaus thereafter. Zebrafish are viable for long term and longitudinal vision studies since their visual acuity remains consistent throughout their lifespan.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.