Abstract
The cutaneous horn on the white spot of the skin in Holstein dairy cattle.
Sadayuki Higuchi*, S. Horigome, G. Tsunoda1), H. Nemoto1) (Kennan Veterinary Clinic of Fukushima prefecture, 1)Fukushima Veterinary clinical & Technical Center)
Nail like phyma was admitted to the Holstein milking cow (about 3-4 years old). The diseased part was composed of two nail like phyma (10×15cm, 2-3cm in high) and many liner phyma (several mm in high) on the white spot of the skin. There were no worthy changes in the clinical symptoms or the blood. The proliferation of eoshinophic horny tissue and flat cells were admitted in phyma on histological examination. The thick epidermis and hyperkeratosis were admitted in the skin near phyma. There was remarkable proliferation of prickle cells in the thick epidermis. We suspected that the phyma in this case was caused by hyperkeratosis of the epidermis. It proved that phyma in this case was like a cutaneous horn. The cause of this phyma was not clear, but the influence of a ray causing solar keratosis was suggested as causing the original disease by phyma only on the white spot of the skin.
