Trigeminothalamic fibre connections in the donkey (Equus asinus) studied by means of the retrograde cell degeneration method.
In this study the left thalamus of seven very young donkeys was transected and the trigeminothalamic fibre connections were investigated by means of the retrograde cell degeneration method. The animals were allowed to survive for a period of 15-45 days and the paraffin sections of the brain stem were stained according to the Klüver-Barrera and the thionine methods. It was found that the principal sensory trigeminal nucleus exhibited retrograde cell changes and cell losses, in its dorsal part, only at the side ipsilateral to the thalamic transection. As far as the nucleus of the spinal tract is concerned, slight changes were found, mainly contralaterally, in its oral subnucleus only. These findings suggest that in the donkey the main trigeminothalamic projection follows an ipsilateral course to the thalamus.
D000818:Animals; D009420:Nervous System; D009434:Neural Pathways; D010527:Perissodactyla / Q000033:anatomy & histology*; D012183:Retrograde Degeneration; D013787:Thalamic Nuclei / Q000033:anatomy & histology; D013788:Thalamus / Q000033:anatomy & histology*; D014276:Trigeminal Nerve / Q000033:anatomy & histology*