Elaine M. Carnevale, DVM, PhD
Office: W131 ARBL Building, Foothills Campus
I teach equine reproduction to Junior and Senior veterinary students. My teaching responsibilities include lectures in VM749, coordinating and teaching Junior Practicum, and teaching Senior Practicum (VM786B). I participate in undergraduate training at the Equine Reproduction Laboratory, and mentor graduate students and visiting international students in research and assisted reproduction in the horse. Additional teaching is provided for a series of short courses held at Colorado State University each fall and winter. The courses provide training for lay people and veterinarians in equine breeding management, ultrasonography, embryo transfer and assisted reproduction technologies.
Research Interests -- Equine Assisted Reproduction
In the past 10 years, assisted reproductive technologies (ART) have greatly expanded for use in the horse, with the development of new technologies and the recognition of offspring by breed registries. The development of ART has been one of my research interests at Colorado State University. The program at Colorado State University is unique in that research is closely associated with a clinical program in assisted reproduction. The result is research and development that is rapidly assimilated into clinical practice.
The primary clinical use of ART in the horse is to establish pregnancies for mares or stallions with poor fertility. Offspring from some mares and stallions are very valuable, providing an economic motive for using ART if other reproductive methods fail. One of the big advances in ART was the establishment of methods to consistently collect oocytes (eggs) from the ovarian follicles of mares. Subsequently, oocyte transfer was developed. Oocyte transfer involves the transfer of a donor mare's oocyte (egg) from her follicle into the oviduct (fallopian tube) of a recipient mare. Using the procedure, we can avoid problems in the reproductive tract of the donor, allowing fertilization and pregnancy to occur in a young, health recipient. Therefore, oocyte transfer can be used to obtain pregnancies from a mare that would otherwise be unable to produce offspring. We have modified the procedures to obtain foals from mares after death or euthanasia for medical reasons; the ovaries are shipped to Colorado State University for the collection and transfer of eggs. For stallions with poor sperm quality or low sperm numbers, sperm can be injected directly into a mare's egg using a process called intracytoplasmic sperm injection (ICSI). Current research is focused on increasing the efficiency of success of ART for old and horses and horses with special reproductive problems. Other research in this area has resulted in increased knowledge of the interactions between oocyte, sperm and oviduct in the horse.
Our abilities to manipulate equine oocytes have advanced; however, many aspects of the oocyte and its surrounding follicle are still poorly understood. Additional research in our laboratory involves the characterization of events associated with maturation of the follicle and oocyte. These events prepare the oocyte for fertilization and are essential for normal fertility. Research in our laboratory is focused on studying maturation events within the follicle, so we can minimize the artifacts that result after the oocyte is removed from its natural environment. One aim of this research is to compare oocyte maturation between young and old mares, using the old mare as a model for reproductive aging in women. The mare may provide a unique model for reproductive aging in women. Age-associated changes in reproduction appear similar between the species. Current research is aimed at studying changes in the follicle and oocyte that occur with aging and affect fertility. The long-term goals are the development of methods to treat some of the causes of reduced fertility associated with aging in the mare and, potentially, the woman.
For further information on current projects, see the page on Reproductive Technology.
Carnevale EM, Squires EL, McKinnon AO. 1987. Comparison of Ham's F10 with CO2 or Hepes buffer for storage of equine embryos at 5C for 24 H. J Anim Sci 65:1775-1781.
McKinnon AO, Carnevale EM, Squires EL, Voss JL, Seidel GE Jr. 1988. Heterogenous and xenogenous fertilization of in vivo matured equine oocytes. J Equine Vet Sci 8:143-147.
Carnevale EM, Ginther OJ. 1992. Relationships of age to reproductive function and uterine efficiency in mares. Theriogenology 237:1101-1115.
Carnevale EM, Bergfelt DR, Ginther OJ. 1993. Aging effects on follicular activity and concentrations of FSH, LH, and progesterone in mares. Anim Reprod Sci 31:287-299.
Carnevale EM, Ginther OJ. 1993. Use of a linear ultrasonic transducer for the transvaginal aspiration and transfer of oocytes in the mare. J Equine Vet Sci 13:25-27.
Carnevale EM, Bergfelt DR, Ginther OJ. 1994. Follicular activity and concentrations of FSH and LH associated with senescence in mares. Anim Reprod Sci 35:231-246.
Carnevale EM, Ginther OJ. 1995. Defective oocytes as a cause of subfertility in old mares. Biol Reprod Monogr 1 (Equine Reproduction VI):209-214.
Carnevale EM, Squires EL, Maclellan LJ, Avarenga MA, Scott TJ. 2001. Use of oocyte transfer in a commercial breeding program for mares with various abnormalities. JAVMA 218:87-91.
Scott TS, Carnevale EM, Maclellan LJ, Scoggin CF, Squires EL. 2001. Embryo development rates after transfer of oocytes matured in vivo, in vitro, or within oviducts of mares. Theriogenology 55:705-715.
Carnevale EM, Maclellan LJ, Coutinho da Silva MA, Checura CM, Squires EL. 2001. Equine sperm-oocyte interaction: Results after intraoviductal and intrauterine inseminations of recipients for oocyte transfer. Anim Reprod Sci 68:305-314.
Scoggin CF, Meira C, McCue PM, Carnevale EM, Nett TM, Squires EL. 2002. Strategies to improve the ovarian response to equine pituitary extract in cyclic mares. Theriogenology 58:151-164.
Coutinho da Silva MA, Carnevale EM, Maclellan LJ, Seidel GE Jr, Squires EL. 2002. Effect of time of oocyte collection and site of insemination on oocyte transfer in mares. J Anim Sci 80:1275-1279.
Maclellan LJ, Carnevale EM, Coutinho da Silva MA, Scoggin CF, Bruemmer JE, Squires EL. 2002. Pregnancies from vitrified equine oocytes collected from super-stimulated and non-stimulated mares. Theriogenology 58:911-919.
Squires EL, Carnevale EM, McCue PM, Bruemmer JE. 2003. Embryo technologies in the horse. Theriogenology 59:151-170.
Carnevale EM, Maclellan LJ, Coutinho da Silva, MA, Squires EL. 2003. Pregnancies attained after collection and transfer of oocytes from ovaries of 5 euthanatized mares. J Am Vet Med Assoc 222:60-62.