Comparative fluorescein angiography of the normal sheep and goat ocular fundi

Fluorescein angiography without sedative or anesthetic agents was evaluated in 20 normal goats and 20 normal sheep. All of the angiographic phases were observed using 20 mg/kg fluorescein IV in both species. Fundus fluorescein angiography results revealed wide stars of Winslow in the tapetal fundus, central or marginal flow during the first part of the arterial phase, delayed filling of the focal areas in the choroid near the optic disc that often coincided with others in the disc, and lack of evidence of the 'striate area' in the tapetal fundi. In goats, the angiographic times were 6.54 +/- 1.25 s for the arterial phase (TA), 7.80 +/- 1.37 s for the arterio-venous phase (TAV), and 14.13 +/- 2.01 s for the venous phase (TV). I1: 1.30 +/- 0.30 s (time elapsing between TA and TAV), and I2: 6.20 +/- 1.60 s (time elapsing between TAV and TV). In sheep, times were 9.54 +/- 2.18 s TA, 11.73 +/- 2.10 s TAV, and 20.86 +/- 2.74 s TV. I1: 2.04 +/- 0.75 s and I2: 8.98 +/- 2.47 s, respectively. Due to the large size of the fundic vessels in sheep and goats, fluorescein angiography of the retinal vasculature can facilitate the study of the different vascular diseases in these species.