Reproduction & Behavior

New Bolton Center, reproduction

New Bolton Center's Section of Reproduction & Behavior provides comprehensive reproductive services for mares and stallions.

Based at the Georgia and Philip Hofmann Research Center for Animal Reproduction, the section’s clinicians have extensive clinical experience enhanced by the latest in research and technology.

The section provides a wide range of reproductive services, from natural breeding to advanced assisted reproductive techniques like embryo transfer. Stallions are a specialty, and the section has extensive experience in dealing with male fertility and behavior problems. The equine behavior service is considered one of the best in the world. The section’s faculty members are board certified by the American College of Theriogenologists.

The Georgia and Philip Hofmann Center for Animal Reproduction at Penn Vet’s New Bolton Center offers a full range of embryo transfer services. Clients can choose to use one of Hofmann Center’s resident recipient mares or provide their own recipient mare. We accept embryos transported from other facilities and recover embryos for domestic transport. Embryo vitrification is available upon request. 


Phone: 610-925-6364

Hofmann Center for Reproduction and Behavior
Bartram Road
(One mile SW of New Bolton Center)
Kennett Square, PA 19348

At New Bolton Center, reproduction specialists work closely with board certified surgeons and internists to provide comprehensive care for dystocias and other reproductive emergencies. The section’s ongoing basic and applied research contributes to the advancement of the theriogenology specialty.

Providing service to the North American animal industries is the Reference Andrology Laboratory. This laboratory provides complete testing of semen from mammalian and avian species which serves as an aid to practitioners working on reproductive issues.

New Bolton Center’s High-Risk Pregnancy Program manages the mare that may have problems with foaling. The ICU is equipped with a specially modified ECG telemetry unit used to monitor and record up to eight fetal heart rates simultaneously without disturbing the mares. Stalls housing the pregnant mares are equipped with low light cameras to monitor signs of labor in a natural setting.

Our team includes five board certified specialists in reproduction or behavior, working in collaboration with sports medicine and imaging, medicine, and surgery colleagues at New Bolton Center, to offer a comprehensive approach to case management.

Dr. Tamara Dobbie Tamara Dobbie, DVM, DACT
  • Director, Hofmann Center
  • Associate Professor, Large Animal Reproduction
  • Board Certification: Theriogenology
Sue McDonnell, Penn Vet, behavior
Sue McDonnell, MS, PhD, CAAB, HMACT
  • Clinical Associate, Equine Behavior
Patricia Sertich Patricia Sertich, VMD, DACT
  • Associate Professor, Large Animal Reproduction
  • Board Certification: Theriogenology
Regina Turner Regina Turner, VMD, DACT
  • Associate Professor, Reproduction
  • Chief, Reproduction & Behavior
  • Board Certification: Theriogenology
Morgan Agnew, VMD, New Bolton CenterMorgan Agnew, VMD
  • Resident
Lauren Pasch, DVM, New Bolton CenterLauren Pasch, DVM
  • Resident
Kristina Soltow, New Bolton CenterKristina Soltow
  • Reproduction Technician
Ben Guessford, New Bolton CenterBen Guessford
  • Stallion Handler
Rick Ladow, New Bolton CenterRick Ladow
  • Stallion Handler

New Bolton Center, reproductionEquine Breeding Services include:

  • Breeding by Natural Cover
  • Semen Collection, Evaluation & Chilled Transport
  • Semen Freezing
  • Mare Cycle Management
  • Artificial Insemination
  • Mare & Stallion Breeding Soundness Examinations
  • Mare & Stallion Infertility Examinations & Therapy
  • Embryo Transfer with Recipient Herd
  • Reproduction-Related Performance Problems

Resources for Our Clients

Specialty Service in Stallion Handling & Behavior:

  • Starting & Re-schooling Stallions for Breeding
  • Dummy Mount Training - Ground Semen Collection
  • Assisting Disabled & Aging Stallions
  • Evaluation & Therapy for Libido, Erection & Ejaculation Dysfunction

Our Equine Behavior Program and Laboratory at New Bolton Center has grown from within the Section of Reproductive Studies. Since the early 1980s, the program has had research as its core activity. The program has included involvement in related clinical and teaching in the veterinary school and continuing education programs nationally and internationally.

Consults, Appointments, and On-Farm Visits

What we offer:

  • Telephone consultations
  • Appointments at our facility
  • On-your-farm visit and/or consultation

Learn more about Equine Behavior and Dr. McDonnell...

Residency: Theriogenology

If you hold a VMD, DVM, or equivalent degree, you can apply for a two-year residency in large animal theriogenology.

Download instructions on how to apply (PDF)...