Dr. Mark C. Walker, BVSc, DACVIM

Internal Medicine


Dr. Walker originates from Auckland, New Zealand. He graduated from Massey University in 1990 with a Bachelor of Veterinary Medicine. After working in a referral clinic in Liverpool, England, he was appointed the position of Junior Lecturer at Massey University. Dr. Walker completed a residency in small animal internal medicine at the University of Florida in 1999, the same year he became a Diplomate of the American College of Veterinary Internal Medicine.

Dr. Walker’s primary interests include patient diagnosis and management as well as actively contributing to veterinary continuing education. He has lectured in the advanced small animal medicine course at the University of Florida and he presents seminars, lectures and workshops to veterinarians locally and nationally. He received the Small Animal Chapter Prize in Small Animal Medicine from the Australian College of Veterinary Scientists. Dr. Walker is a member of the American Animal Hospital Association, Florida Veterinary Medical Association, Big Bend Veterinary Medical Association and the Comparative Gastroenterology Society.

Dr. Walker has a number of journal and proceedings publications. He has authored chapters in the second and third edition of The 5 Minute Veterinary Consult and third edition of Slatter’s Small Animal Surgery textbook. Dr. Walker’s medical interests include cardiology and gastroenterology. Dr. Walker is married to Dr. Olga Walker. They have 5 children and a Staffordshire Bull Terrier named Luna.


  • 1999-2012: Associate North Florida Veterinary Specialist
  • 2001-2004: Research Scientist, Gene Therapy for Anemia (cats) and Pompe’s Disease (human cardiomyopathy), Applied Genetic Technologies Corporation Inc.
  • 1996-1999: Resident, University of Florida
  • 1998: ACVIM Boarded (Small Animal Internal Medicine)
  • 1996: MACVSc (Internal Medicine)
  • 1994-1996: Junior Lecturer, Massey University, New Zealand
  • 1990-1994: Associate and Intern, Rutland House Veterinary Hospital, Liverpool, United Kingdom
  • 1990: MRCVS


Anesthesia and Critical Care


Dr. Shih is double-boarded in Veterinary Anesthesia and Analgesia and in Veterinary Emergency and Critical Care. He graduated from the University of Sao Paolo in Brazil with his doctorate degree in Veterinary Medicine in 1999. He completed his residency in Veterinary Anesthesia at the University of Florida. He then completed a fellowship in Veterinary Emergency Medicine and Critical Care. Dr. Shih is boarded in both the American College of Veterinary Emergency Critical Care and also in the American College of Veterinary Anesthesia and Analgesia. Following his residency and fellowship, he spent 12 years on faculty as an associate professor in the Department of Anesthesia at the University of Florida College of Veterinary Medicine. He joined the staff at Capital Veterinary Specialists, Jacksonville in 2016 and is excited to be serving the First Coast. Dr. Shih's areas of interest include preload monitoring, hypovolemic shock, and cardiopulmonary resuscitation.

Dr. Shih is married and has two children. He enjoys fishing with his sons in his free time.


2013 - 2016: Associate Professor, Department of Anesthesia, University of Florida College of Veterinary Medicine
2007 - 2013: Assistant Professor, Department of Anesthesia, University of Florida CVM
2009 - 2016: Fellowship in Veterinary Emergency and Critical Care, University of Florida CVM
2007: Boarded by the American College of Veterinary Anesthesia and Analgesia
2004 - 2007: Veterinary Anesthesia Residency, University of Florida CVM
2003: Boarded by the American College of Veterinary Emergency and Critical Care
1994 - 1999: Doctor of Veterinary Medicine, University of Sao Paolo, Brazil, School of Veterinary Medicine

Dr. Steven Neihaus, DVM, DACVS



Dr. Neihaus is a Chicago area native and came to the surgery department of Capital Veterinary Specialists in May 2015. He attended the University of Florida in Gainesville for his undergraduate education. After graduating from the University of Illinois College of Veterinary Medicine, Dr. Neihaus spent a year as a general practitioner before going on to complete a rotating internship at the Animal Emergency and Referral Center (now Blue Pearl Veterinary Partners) in Northbrook, Illinois. During his residency at Affiliated Veterinary Specialists under Dr. Robert Goring, Dr. Neihaus published multiple research papers, presented at national veterinary conferences and was the recipient of the prestigious Clinical Research Award at the American College of Veterinary Surgeons Residents Forum.

Dr. Neihaus’ professional interests include minimally invasive surgery (arthroscopy and laparoscopy), oncologic surgery and soft tissue reconstruction, and complex orthopedic and fracture repair. As a dedicated member of his community, Dr. Neihaus also enjoys giving back. Dr. Neihaus donates his time and surgical skills to help special needs cases from various rescue organizations around the country. Dr. Neihaus is a member of the Veterinary Society of Surgical Oncologists, Veterinary Orthopedic Society, and local and national veterinary medical associations.

Dr. Neihaus and his wife, who is also a veterinarian, live in the Mandarin area with their two sons and Dalmation mix, Lucy. When not at work, Dr. Neihaus enjoys fishing, boating, playing and coaching ice hockey and cheering on his favorite sports teams – the Chicago Bears, Blackhawks and the Florida Gators.


  • 2011-2015: Associate Surgeon – Chicago Veterinary Emergency and Specialty Center
  • 2012: Board Certification – American College of Veterinary Surgeons
  • 2010: American College of Veterinary Surgeons Residents Forum Award for Clinical Research
  • 2008-2011: Surgical Residency w/ Dr. Robert Goring
  • 2006-2007: Rotating Internship – Animal Emergency and Referral Center, Northbrook, Illinois
  • 2005: Doctor of Veterinary Medicine with Honors – University of Illinois, Illinois
  • 1998-2001: Undergraduate – University of Florida, Gainesville, Florida

Dr. Brett Darrow, DVM, CCRP, Residency Trained in Small Animal Surgery



Dr. Darrow will soon join Capital Veterinary Specialists in September, 2017! He was born in Iowa and maintains strong ties to his family and blue-collar Midwest roots. After completing his undergraduate studies and working for one year as a chemical engineer, Dr. Darrow realized true fulfillment could come working with animals and enrolled at the University of Wisconsin. After earning his veterinary degree, Dr. Darrow performed a rotating internship followed by one year of general practice medicine in Bremen, Germany and emergency medicine in Ft. Lauderdale, FL. It was while volunteering at several local wildlife rehabilitation centers that Dr. Darrow realized how much he enjoyed the surgical aspects of animal care.

Dr. Darrow has completed his residency in small animal surgery at the University of Tennessee. His current research lies in 3D printing bone models and surgical guides to improve the accuracy and efficiency of orthopedic surgery. Dr. Darrow has authored several peer-reviewed scientific publications and has lectured nationally on topics ranging from surgical infection control to avian (bird) surgery. He is currently co-authoring a chapter in the newest edition of Small Animal Veterinary Surgery. His professional interests include minimally invasive surgery, wildlife and exotic animal surgery, and complex orthopedic procedures. He is a member of the Veterinary Society of Surgical Oncologists, Veterinary Orthopedic Society, and American Veterinary Medical Association.

Dr. Darrow is married to Dr. Janina Bartels, and together they look after Emely, a 15-year-old jack Russell terrier. In their free time, they enjoy virtually all outdoor pursuits including camping, mountain-biking, running, snorkeling, fishing, surfing, and snow-boarding. To Dr. Neihaus’ dismay, they are die-hard Packer fans.

  • September 2017!: Associate Surgeon – Capital Veterinary Specialists
  • 2014-2017: Small animal surgery residency – University of Tennessee, Knoxville, TN
  • 2013-2014: Emergency veterinarian – Lauderdale Veterinary Specialists, Ft. Lauderdale, FL
  • 2012-2013: General practice – Tierärtzeliche praxis van Loosen, Bremen, Germany
  • 2011-2012: Rotating internship – VCA Veterinary Care and Referral Center, Albuquerque, NM
  • 2007-2011: Doctor of Veterinary Medicine with Honors – University of Wisconsin, Madison, WI
  • 2000-2005: BSE Chemical engineering – University of Iowa, Iowa City, IA

Dr. Rick Alleman, DVM, PhD. Diplomate ABVP & ACVP

Clinical Pathologist


Dr. Rick Alleman received his DVM degree from Louisiana State University and practiced companion animal medicine and surgery for 9 years in a private, small animal practice in New Orleans. In 1987, he became board certified as a Diplomate of the American Board of Veterinary Practitioners with a specialty in companion animal practice. He was re-certified in 1997 and 2007.

Dr. Alleman completed a residency in Clinical Pathology at the University of Florida and became a Diplomate of the American College of Veterinary Pathologists with a specialty in Clinical Pathology and completed his PhD degree in molecular biology of vector-borne diseases. He is a former Professor, Service Chief, Resident Coordinator and Director of Laboratories at the University of Florida, College of Veterinary Medicine, where he was on faculty for 20 years. He is currently Manager of Lighthouse Veterinary Consultants. He is a consultant and serves on the Advisory Boards for IDEXX Laboratories, Merck Animal Health, and Zoetis.

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