Equine Research

UF Surgical Translation & 3D Printing Research Lab

About

UF Equine Performance Laboratory

Drug studies include:

• Common medications that are cited as having performance-altering potential, but for which the elimination time is unknown.
• Medications for which the Division of Pari-Mutuel Wagering wishes to write rules for use in racing horses.
• Drugs for which the Racing Laboratory is improving detection techniques.
• Any medication or compound which may have regulatory importance, but about which scientific information is lacking.

Funding for these studies has come from:

• The Racing Medication and Testing Consortium
• The American Quarterhorse Foundation
• University of Florida Development funds
• Private contributors to UF for the support of race horse research
• The Pari-Mutuel Wagering Competitive grants fund
• NIH

Equine Reproduction Laboratory

Mares with Placentitis

Work in our laboratory has focused on effective treatments for mares experiencing placentitis. Most recently, we have treated mares with different antibiotics to determine if the drugs will combat bacterial infections of the placenta in mares. Cephalosporins are an antibiotic class that is highly effective against many types of bacteria in horses, including those that cause placentitis. We are determining if both a daily administered cephalosporin antibiotic (ceftiofur sodium, Naxcel) and a long-acting cephalosporin antibiotic (ceftiofur crystalline free acid, Excede) cross the placenta in mares and reduce placental infection. Our goal is to verify that these drugs are effective for treating mares with placentitis as they are commonly used in practice.

Fertility problems in breeding stallions

Fertility problems in breeding stallions cause significant financial losses in the equine industry. Currently, available treatments of testicular dysfunctions in stallions on semen quality have low efficacy. There are numerous new developments in this area in human medicine, but few preliminary studies conducted on normal stallions did not show any significant effects of these treatments on semen parameters. In order to increase our chances for success in future studies on medical treatment of this condition, our laboratory has recently established  a model of testicular degeneration in stallions, using a new candidate for male contraceptive, RTI-4587-073(l).

A single administration of this compound to the miniature horse stallions severely affected testicular function and structure, which was consistent with testicular degeneration. Currently, we are planning to use this model to conduct a study on the effectiveness of a combined treatment with pentoxifylline and Vitamin E in improving testicular function in stallions with testicular degeneration. We have already shown that a long-term treatment with pentoxifylline improves testicular perfusion in stallions. In addition, a combined treatment with pentoxifylline and antioxidants has beneficial effects in both men and women with fertility problems. Therefore, we expect that this treatment will have positive effects on testicular function in stallions with medically induced testicular degeneration.

The value of the proposed research is particularly high for the Thoroughbred industry, since only natural breeding is allowed in this breed, and a breeding stallion is expected to deposit good quality semen into the mare’s reproductive tract. Therefore, therapies for testicular dysfunctions in these stallions have to be administered to the animal itself, and not to semen, which was collected from him. The proposal of this project was recently submitted to the Grayson-Jockey Club Research Foundation for funding.

Island Whirl Equine Colic Research Laboratory

The Island Whirl Equine Colic Research Laboratory (IWECRL) in the Department of Large Animal Clinical Sciences (LACS) was endowed in 1988 by Mr. And Mrs. William Harder in honor of their highly regarded Thoroughbred stallion, “Island Whirl.” The activities of the laboratory are directed at expanding our knowledge concerning the normal function of the equine gastrointestinal tract and ways in which we can improve prevention and treatment of colic. The IWECRL endowment maintains a well-equipped laboratory complex that accommodates in vivo and ex vivo research projects. In addition, this well-equipped laboratory has attracted extramural grant support on colic-related issues from Morris Animal Foundation, American Quarter Horse Association, and the Grayson Jockey Club Research Foundation. It also provides a research facility for graduate students funded by other sources, but particularly those that receive a stipend and tuition coverage from the Deedie Wrigley-Hancock Fellowship for Colic Research. Numerous publications and abstracts have been generated from research projects in the IWECRL.

Credit for the development of the IWECRL belongs to Dr. Al Merritt, who retired as Director in 2004. He was followed in this role by Dr. David Freeman, who is an experienced equine surgeon that specializes in colic surgery. Dr. Freeman’s primary goal as a surgeon is to increase survival after colic surgery through improving surgical management and postoperative care, and increasing the availability of effective treatments to horse owners through responsible cost management.

Dr. Sanchez is a large animal internist, who successfully completed her PhD research through the IWECRL and has similar interests as Dr. Merritt, also brings to the group a strong interest in gastrointestinal motility disorders and pain management. Other faculty members are Dr. Ali Morton and Dr. Anje Bauck, both of whom have strong clinical interests in colic surgery and have contributed to colic research in the IWECRL. As a group, all of us strive to improve the welfare of the horse and to leave this wonderful animal a legacy that will long outlast us and improve its wellbeing forever.

Accomplishments of the IWECRL are as follows:

• Gastric ulcers are an intriguing but critical disease in horses. Dr. Merritt and Dr. Sanchez have advanced our understanding of the pathophysiology of these diseases and their pharmacological prevention and management. Both are regarded internationally as experts in equine gastric ulcer syndrome based on research from IWECRL, most evident In Dr. Sanchez’ role in collaborating with the University of Copenhagen to support a PhD student, Dr. Louise Husted. Dr. Merritt and Dr. Sanchez have also successfully investigated the potential to modify gastrointestinal tract dysmotility and pain by various drugs in common usage.   
• Dr. Freeman, Dr. Astrid Grosche, Dr. Morton and Dr. Bauck have examined ability of small intestine and large intestine to repair in vivo and ex vivo after brief periods of ischemia, and have gained useful information about the recovery process and means of manipulating it to the horse’s advantage. Particularly noteworthy was the finding that inflammation in one intestinal segment actually induced inflammation in distant unmanipulated intestinal segments. Part of this research was supported by a very prestigious first award for Dr. Grosche from the Morris Animal Foundation, and therefore provided a critical step in her career. Collaboration with colleagues in Denmark produced further insights into the inflammatory process and its assessment. Research by Dr. Julia Daggett in IWECRL earned her a Master of Science degree and demonstrated that inflammation in the gastrointestinal tract can induce distant responses in lungs, liver and kidneys.
• Dr. Freeman published a study on water consumption in healthy horses that demonstrated the magnitude of the effect of feed intake and the subsequent digestive process on water needs in this large herbivore. Results of this study on a previously neglected aspect of gastrointestinal physiology should be considered when applying fluid therapy in horses, especially when addressing maintenance needs in horses that are not eating for a variety of reasons.
• Dr. Freeman, Dr. Bauck and Dr. Ruethaiwan Vinijkumthorn (PhD student from Thailand) have demonstrated that the widely used nonsteroidal anti-inflammatory drug, phenylbutazone, can inhibit bicarbonate secretion by the right dorsal colon. This secretion appears to be unique to the right dorsal colon, and its loss could mean reduced buffering of the intense acid production during fermentation in this segment. This finding raises the possibility that right dorsal colitis in horses is a drug-induced form of cystic fibrosis, which in turn suggests that treatments to restore or replace the effects of this secretion need to be explored. Both Dr. Bauck and Dr. Vinijkumthorn earned PhDs from their research on this topic, which was enhanced by collaboration with Dr. Sadasivan Vidyasagar, in the UF College of Medicine.
• Other projects recently completed, accepted for publication, or nearing completion, and made possible by the IWECRL, address features of different small intestinal anastomoses, effects of body position on closure of the abdominal incision, and a method for correcting a difficult small intestinal strangulation.
• Five graduate students have completed their programs through the IWECRL, including 4 that earned PhDs and one Master of Science degree. All research conducted in this laboratory has been published, is accepted for publication, or has been presented at an international meeting, such as the Equine Colic International Research Symposium.

Future research will focus on the efficacy of different intestinal anastomoses that are relevant to treatment of common small intestinal strangulating diseases in horses, markers of risk for strangulating lipomas in horses, and effects of rates of infusion of intravenous fluids on the intestinal microcirculation. We are optimistic that we can continue these lines of investigation to improve survival in horses from colic, a cruel and deadly disease.