Reproductive Biology

Bruce W. Christensen, DVM, MS, DACT

Clinical Theriogenology

VMTH

Dr. Christensen is a board-certified theriogenologist whose clinical work focuses on equine and canine reproduction. Dr. Christensen's research interests focus on endangered species reproduction. He has used domestic species as models for their endangered counterparts, such as using dogs as models for the Mexican gray wolf and horses as models for Somali Wild Ass, Przewalski horses, or even rhinoceros. Current research that may involve students includes investigating ways of transporting semen over distances, combating endometritis, and the effects of phytoestrogens on reproductive cycles. Students would be involved with assessing reproductive behaviors, collecting semen and blood, and performing semenalysis.

Ghislaine Dujovne, DVM, MS

Assistant Professor in Clinical Theriogenology

VMTH

Dr. Dujovne is a theriogenologist whose clinical work focuses mainly in equine reproduction. Dr. Dujovne's research interests focus on reproductive problems of clinical relevance on mares and stallions. Dr Dujovne’s main interest is efficient clinical management of reproductive diseases and artificial reproductive techniques. She has participated in research related with estrus suppression in performance mares, endometritis treatment in mares, stallion semen quality, post-mortem sperm recovery in stallions and semen evaluation in canine semen.

CONTACT EMAIL:  gadujovne@ucdavis.edu

Pascal Gagneux, Ph.D.

Affiliated with UC Veterinary Medical Center – San Diego

(See also: Biochemistry/Cell Biology)

Dr. Gagneux is interested in primate molecular diversity. His lab investigates the evolutionary mechanisms responsible for the generation and maintenance of primate diversity, its potential roles in protecting populations from pathogens as well as potential consequences for reproductive compatibility. He is currently studying cell-surface molecules of sperm cells in closely related primate species. His focus is on glycans, the oligosaccharides attached to glycolipids and glycoproteins of the cell surface. The numerous parallels between the surface molecules of successful pathogens and those found on the surface of mammalian sperm, invite the analogy between internal fertilization and “extremely successful infection”. These interests examine the differences in sperm surface molecules  and sexual selection (via sperm competition and cryptic female choice) and whether such differences might contribute to reproductive incompatibility and speciation due to female immune rejection of sperm with incompatible glycoconjugates. Dr. Gagneux has studied the behavioral ecology of wild chimpanzees in the Taï Forest, Ivory Coast, population genetics of West African chimpanzees, and differences in sialic acid biology between humans and great apes with special consideration of their differing pathogen regimes. His great concern is that the current surge in interest for comparative genomics is not being translated into direct support for the conservation of primates in their endangered natural habitats.

Please contact Peter Ernst pernst@ucsd.edu or Christina Sigurdson csigurdson@ucsd.edu first for more information

Stuart Meyers, DVM, PhD

Reproduction, aging and sperm physiology and cryopreservation, male effects on embryo development, and germ cell transplantation in endangered fish

VM: Anatomy, Physiology & Cell Biology

Dr. Meyers is a veterinarian, professor, and researcher in the SVM with special interest in reproduction. Research in our laboratory has centered on gamete cryopreservation and an understanding of the role of the paternal genome on embryo development and fertility.  Our newest research area is germ cell transplantation of endangered fish into surrogate non-endangered species. Our study models are the rhesus monkey, stallion, dog, and endangered fish. Our goals are to develop an understanding of fundamental mechanisms of cellular damage caused by low temperature storage, and then to use this knowledge to develop new methods for gamete preservation and subsequent fertility. We use a variety of techniques including flow cytometry and confocal, fluorescence, and electron microscopy to evaluate the integrity of sperm cell organization and cell function. 

Please visit Dr. Meyers's website at: http://faculty.vetmed.ucdavis.edu/faculty/smeyers/

Swee Teh, Ph.D.

Department of Anatomy, Physiology, and Cell Biology (see also: aquatic health, pathology, pharmacology/toxicology)

Independent research in the fields of developmental biology, nutrition, pathology, and ecotoxicology. Special emphasis on adverse effects of environmental endocrine disruptors and other contaminants in the embryonic development, growth, and reproduction of invertebrates, fish and shellfish populations. Development of biomarkers of exposure and deleterious effects in aquatic organisms. Development of a screening assay for endocrine disrupting chemicals utilizing microarray technology.

Research will include:

1. The culture of native (salmon, delta smelt, and splittail) and surrogate (Medaka) fish models for use in carcinogens, endocrine disruptors and toxicants testing;
2. Design QA/QC & safety protocols for animal care & exposure experiment. Acute and chronic toxicity testing of contaminants and toxicants using native and non-native fish;
3. The long-term, sublethal growth and reproductive effects of fish exposed to contaminant-laden diets (metals, and organic chemicals including endocrine disruptors and pesticides);
4. Development and use of biochemical, molecular, and histopathologic indicators (biomarkers) of exposure to determine the sublethal deleterious effects of environmental pollutants on fish and aquatic invertebrate populations;
5. Development and the application of toxicogenomics in aquatic toxicology testing;
6. Effects of toxicants on quality and quantity of food chain organisms and resultant consequences on the higher trophic organisms.
7. Integrate growth, biochemical, molecular, histopathologic, and reproductive indicators into an individual and population health effects and extrapolation of population level effects to ecosystem health effects.

Active Projects's

1. Groundwater ambient monitoring and assessment program - Hexavalent chromium and endocrine disrupting chemicals.
2. Using a Sensitive Japanese Medaka (Oryzias Latipes) Fish Model for Endocrine Disruptors Screening.
3. Histopathological examinations of larval and juvenile pelagic fish.
4. Biomass and Toxicity of a Newly Established Bloom of the Cyanobacteria Microcystis Aeruginosa and its Potential Impact on Beneficial Use in the Sacramento-San Joaquin Delta.

Please visit Dr. Teh's website at: http://faculty.vetmed.ucdavis.edu/faculty/sjteh/