The Animal Emergency doctors at Nashville Veterinary Specialists - Clarksville see patients for emergencies during weekday evenings and 24/7 on weekends and holidays. You don’t need an appointment or referral to use our emergency services. The veterinarians who specialize in surgery and internal medicine see patients for scheduled non-emergency appointments Mondays-Fridays during the day. A referral from your primary care veterinarian is needed to schedule an appointment with one of our specialists.