Bovine Skin Diseases Study Guide

Overview and Clinical Importance

This study guide covers two high-yield bovine skin conditions: Ocular Squamous Cell Carcinoma (OSCC) and Dermatophytosis (Ringworm). OSCC is the most common neoplasm in cattle, accounting for approximately 80% of tumors identified at slaughter, while dermatophytosis represents the most common fungal skin infection in cattle with significant zoonotic potential.

Section 1: Ocular Squamous Cell Carcinoma (Cancer Eye)

Definition and Epidemiology

Ocular squamous cell carcinoma (OSCC), commonly called "cancer eye," is a primary neoplasm of epithelial origin affecting the ocular and periocular structures of cattle. It represents the most economically significant tumor in the cattle industry, with losses estimated at approximately $20 million annually in the United States alone.

OSCC predominantly affects cattle over 5-7 years of age and rarely occurs in animals less than 3 years old. The prevalence varies geographically, being higher in southwestern regions and lower latitudes with greater UV exposure.