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Objective: Our aim was to generate baseline optical coherence tomography (OCT) measurements of retinal thickness in female Beagles and to determine how these are affected by meridian, eccentricity, and age. Methods: Twenty‐three female Beagles, including six puppies (<6 months old), six mature (1.8‐8.2 years old), and 11 elderly dogs (>11 years old) were studied. Both retinas of each dog were scanned (in 4 principal meridians) using the Heidelberg Spectralis following ophthalmic examination, refraction, and sedation. In each eye and each meridian, total retinal, outer retinal, and nerve fiber layer (NFL) thickness were measured from the disc rim up to 6 mm peripherally. Results: The canine retina is thickest dorsally and thinnest ventrally. Total retinal, outer retinal, and NFL thickness decrease progressively and significantly as a function of eccentricity. The greatest eccentricity‐dependent thinning occurs dorsally. This thinning is due mostly to NFL tapering, while the eccentricity‐dependent change in outer retinal thickness is more moderate, especially in the lateral meridian, possibly due to the presence of the visual streak. The retina is thickest in puppies, but there were no significant differences between mature and elderly dogs. Conclusions: Our results provide normative values for total, outer, and inner retinal thickness in female dogs and may facilitate OCT use in the diagnosis of canine glaucoma and inherited retinopathies. [ABSTRACT FROM AUTHOR]

Objective: To investigate age‐associated changes of flash visual evoked potentials (FVEPs) in sedated horses. Animal studied: Twenty‐eight clinically healthy Standardbred Warmblooded trotters, aged 36 hours to 28 years. Procedures: Light‐adapted FVEPs and FERGs were recorded (An‐vision RETIport, Roland‐consult, Germany) in response to flash stimuli. Sedation was obtained using alpha‐2‐agonists intravenously. Akinesia of the eyelids was induced and pupils were dilated. Results: Reproducible FVEPs and FERGs were readily recorded from all foals and horses. The FVEP waveform included up to four positive components (P1‐P5) and two negative components (N1 and N2) and FVEP waveform morphology was similar across all age groups. Some differences in peak times and amplitudes associated with increasing age were observed. FVEP amplitudes recorded from newborn foals were well above the amplitudes observed in normal adult horses and FVEP peak times were somewhat shorter. In adult horses, a significant increase in P4 peak time and a gradual decrease in amplitudes, mainly for N2P4, were seen across the life‐span. Conclusions: The overall equine FVEP waveform was similar across the normal life‐span of the horse in our cross‐sectional study. We found that the visual system of the foal seems to be well developed already at birth. Furthermore, our results showed a decrease in amplitudes and increase in some peak times with increasing age. We recommend that age‐matched controls should be used when evaluating foals and young horses in clinical practice, whereas horses over the age of three years can be compared to other adult horses. [ABSTRACT FROM AUTHOR]