Progress 09/01/00 to 08/31/06
Outputs
Dairy cows enrolled in the NC 1006 Dairy Project that developed spontaneous ovarian cysts during the project were identified as a subgroup of the treated cows and their reproductive records and endocrine profiles examined to determine cows treated with the Ovsynch protocol (GnRH+PGF+GnRH and timed AI) have similar reproductive performance as cows treated with Ovsynch plus CIDR. Cows have been enrolled in the study and progesterone concentrations have been determined. Currently, data are undergoing analysis.
Impacts
We expect to demonstrate that cows with ovarian cysts that are treated with the Ovsynch + CIDR protocol have reproductive performance superior to cows treated with the Ovsynch protocol alone. If our hypothesis is correct, reproductive performance and subsequent milk production in affected dairy cows will be improved.
Publications
- No publications reported this period
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Progress 01/01/03 to 12/31/03
Outputs
We have participated in the NC 1006 Dairy Project and have enrolled approximately 80 cows. The hypotheses of the project are 1) anovulatory dairy cows can be identified by a) heat detection patches or b) one or two ovarian examinations by ultrasound; 2) anovulatory dairy cows have improved pregnancy rates after treatment with progesterone and GnRH; and 3) altering timing of timed AI (TAI) relative to an ovsynch-like protocol will maximize pregnancy rates in anovulatory and cycling dairy cows. Blood samples for nutritional profiles and hormonal analysis have been obtained and will be analyzed later.
Impacts
The purpose of this project is to improve pregnancy rates in dairy cows and make milk production on modern dairy farms more efficient.
Publications
- KR Kieborz-Loos, HA Garverick, DH Keisler, SA Hamilton, BE Salfen, RS Youngquist and MF Smith. 2003. Oxytocin-induced secretion of p rostatiandin F2alpha in postpartum beef cows: Effects of progesterone and estradiol-17beta treatment. J. Anim. Aci. 81:1830-1836.
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Progress 01/01/01 to 12/31/01
Outputs
Ovarina cysts were induced in cows and the animals were treated with intravaginal progesterone. Blood samples have been collected to characterize the luteinizing hormone profile of treated and control animals. Assays for gonadotropins and ovarian steroids are currently pending.
Impacts
We expect the results of this project to yield a more effective method of clinical management of ovarian cysts in dairy cows.
Publications
- No publications reported this period
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Progress 01/02/00 to 12/31/00
Outputs
Holstein and Guernsey dairy cows tentatively diagnosed with cystic ovarian disease during routine reproductive examinations are enrolled in this clinical trial. The ovaries of these cows are subsequently examined thrice weekly by transrectal ultrasnongraphy to make a definitive diagnosis of ovarian cysts based on size (greater than 20 mm diamter) and persistence (10 days or more). Blood samples are obtained for measurement of serum progesterone concentrations at each examination. Cows in which cysts persist for at least 10 days are treated with an intravaginal progesterone releasing device which is left in situ for 9 days. On the day before withdrawal of progesterone, cows are treated with 25 mg dinoprost tromethamine. Ultrasound examinations are continued until the cow ovulates or another follicular cyst develops. A sufficient number of cows has not yet been treated to permit critical evaluation of the data, but to date, all cows treated with intravaginal
progesterone have ovulated within a few days after cessation of treatment.
Impacts
The preliminary data available to date suggest that intravaginal progesterone may be a more effective method of correcting cystic ovarian disease than the traditional methods of treatment. Further, restoration of normal estrous cycles may occur earlier, thus fewer days open result from this common cause of infertility in dairy cows.
Publications
- No publications reported this period
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Progress 01/01/99 to 12/31/99
Outputs
Progress narrative: Holstein and Guernsey cows affected by chronic ovarian cysts were included in a clinical study. Cows included had been treated one or more times with GnRH but had not responded positively. Ovarian cysts were confirmed by ultrasound examination and cows were treated with progesterone delivered by a CIDR (controlled internal drug release). On the day CIDR's were removed, cows were treated with prostaglandin F2-alpha (dinoprost) and observed for estrus three times daily. The ovaries were examined by ultrasound and serum samples taken for progesterone assay thrice weekly. Cows were inseminated when estrus was detected. Pregnancy was diagnosed by ultrasound examination between 28 and 35 days after insemination if cows had not been subsequently detected in estrus. At the end of the project, all cows had been diagnosed pregnant after one or several inseminations. Data are currently being reviewed and analyzed for publication.
Impacts
Impact: Ovarian cysts are a significant cause of delayed breeding and subsequent economic loss to the dairy industry in the United States. While GnRH is an effective treatment in many cases, some cases seem to be refractory and the condition persists despite treatment. We believe the data generated by this project offers a basis for an alternative mode of therapy and will benefit dairy producers.
Publications
- Calder MD, BE Salfen, B Bao, RS Youngquist, HA Garverick: Administration of progesterone to cows with ovarian follicular cysts results in a reduction in mean LH and LH pulse frequency in initiates ovulatory follicular growth. J Anim Sci (1999) 77:3037-3042.
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Progress 01/01/98 to 12/31/98
Outputs
The primary focus of the theriogenology section is in the area of food animal reproduction but substantial clinical service is rendered to horses and small companion animals. Caseload in each of these areas was: equine-1,790; food animal-1,632; ambulatory visits-683 with 8,261 animals treated. Reproductive services include examination of individual animals and herds for pregnancy by manual palpation and ultrasonography; examination of male animals (bulls and stallions) for potential breeding soundness; restorative surgery for injuries of the reproductive organs of bulls; diagnosis and treatment of individual and herd cases of infertility; and artificial insemination of mares and bitches.
Impacts
(N/A)
Publications
- Manimmam, M., Calder, M.D., Salfen, B.E., Younquist, R.S., Keisler, D.H., Garverick, H.A. 1998. Effect of luteinizing hormone (LH) infusion on gene expression of cytochrome P450 aromatase and concentration of steroids in 2nd wave bovine ovarian follicles. Biol. Reprod. 58:438.
- Bao, B., Calder, M.D., Xie, S., Smith, M.F., Salfen, B.E., Youngquist, R.S., Garverick, H.A. 1998. Expression of steroidogenic acute regulatory protein messenger ribonucleic acid is limited to theca of healthy bovine follicles collected during recruitment, selection and dominance of follicles of the first follicular wave. Biol. Reprod. 59:953-959.
- Yuan, .W, Bao, B., Garverick, H.A., Youngquist, R.S., Lucy, M.C. 1998. Follicular dominance in cattle is associated with divergent patterns of ovarian gene expression for insulin-like growth hormone factor (IGF)-I, IGF-II, and IGF binding protein-2 in dominant and subordinant follicles. Domest Anim. Endocrin. 15:55-63.
- Evans, T.J., Ganjam, V.K., Miller, M.A., Niswender, K.D., Krause, W.J., Youngquist, R.S. Autoradiographic, morphometric, and ultrastructural analysis of the role of angiotension converting enzyme (ACE) in the pathogenesis of equine endometrial periglandular fibrosis (EPF). Proc Soc for Theriogenology, Baltimore, MD, 4-6 Dec 1998, pp 167-168.
- Evans, T.J., Miller, M.A., Ganjam, V.K., Niswender, K.D., Ellersick, M.R., Krause, W.J., Youngquist, R.S. 1998. Morphometric analysis of endometrial periglandular fibrosis in mares. Am. J. Vet. Res. 59:1209-1214.
- Calder, M., Salfen, B.E., Manikkam, M., Youngquist, R.S., Garverick, H.A. 1998. Follicular-fluid steroid-hormone concentrations and expression of cytochrome P450 aromatase messenger RNA in developing dominant follicles of cows with normal estrous cycles compared to cows with follicular cysts. Biol. Reprod. 58:437.
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Progress 01/01/97 to 12/31/97
Outputs
In a collaborative project, the objectives were to characterize the changes in expression of mRNAs for gonadotropin receptors and steroidogenic enzymes during growth, dominance, and atresia of bovine ovarian follicles. Expression of mRNA for steroidogenic enzymes was first detected in recruited follicles in the granulosa layer but not in smaller follicles. mRNA for luteinizing hormone receptor was first detected in the granulosa layer of follicles greater than 9 mm in diameter, similar to the time of selection. The objective of a second study was to determine if there were detectable levels of angiotensin converting enzyme (ACE) in the endometrium of mares and determine if there were any relationship to development of endometrial periglandular fibrosis (EPF). An increase in endometrial ACE was, possibly as a result of myofibroblastic transformation of periglandular fibroblasts appears to play a role in the pathogenesis of EPF.
Impacts
(N/A)
Publications
- Bao H, HA Garverick, GW Smith, MF Smith, et. al. 1997. Expression of messenger RNA encoding 3Beta-hydroxysteroid dehydrogenase/ 5-4 isomerase (3Beta-HSD) . Biol Reprod 56:1466-1473.
- Bao B, Calder MD, Smith MF, Youngquist RS, et. al. 1997. Steroidogenic acute regulatory protein messenger ribonucleic acid (mRNA) expression . Biol Reprod 56(Suppl 1):143 abstract 243.
- Youngquist RS (ed). 1997. Current Therapy in Large Animal Theriogenology. Philadelphia, W.B. Saunders Co.(898 pp).
- Youngquist RS. 1997. Pregnancy diagnosis. In: Current Therapy in Large Animal Theriogenology, WB Saunders Co, Philadelphia. pp
- Youngquist RS. 1997. Parturition and dystocia. In: Current Therapy in Large Animal Theriogenology, WB Saunders Co, Philadelphia. pp
- Youngquist RS, Shore MD. 1997. Postpartum uterine infections. In: Current Therapy in Large Animal Theriogenology, WB Saunders Co, Philadelphia. pp 335-340.
- Youngquist RS. 1997. Surgical correction of . In Youngquist RS (ed): Current Therapy in Large Animal Theriogenology, WB Saunders Co, Philadelphia. pp 429-440.
- Bao B, HA Garverick, GW Smith, et. al. 1997. Changes in messenger RNA encoding cytochrome P450 side chain cleavage, cytochrome P450 . Biol Reprod 56:1158-1168.
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Progress 01/01/96 to 12/30/96
Outputs
In an effort to develop a more accurate diagnostic test for bovine venereal trichomoniasis, three adult bulls were purchased and infected with Tritrichomonas foetus by infusion of cultured organisms into the preputial cavity. Biopsies of the preputial mucous membrane were obtained before and at intervals after the bulls were infected. The hypothesis was that organisms could be identified in tissue samples after staining with immunofluorescent monoclonal antibodies to T. foetus. To date, attempts to obtain consistently stained samples have not been successful. Efforts to refine the process continue.
Impacts
(N/A)
Publications
- Smith GW, et.al. Ontogenies of messenger RNA encoding tissue inhibitor of metalloproteinases 1 and 2 within bovine preovulatory follicles... Dom Anim Endocrinol 13:151-160 (1996).
- Bao H, et. al. Changes in messenger RNA encoding cytochrome P450 side chain cleavage, cytochrome P450 17"-hydroxylase and cytochrome P450 aromatase during... Biol Reprod (1997) (in press).
- Bao H,et. al. Changes in messenger RNA encoding 38-hydroxysteroid dehydrogenase/)5-)4 isomerase (38-HSD) during recruitment and selection of bovine ovarian... Biol Reprod (1997) (in press).
- Xu Z, et al. Expression of follicle-stimulating hormone and luteinizing hormone receptor messenger ribonucleic acids in bovine follicles during the first... Endocrino 136:981-989, 1995. PB Xu ZZ, et. al. Expression of messenger RNA encoding cytochrome P450 side chain cleavage, cytochrome P450 17"-hydroxylase and cytochrome P450 aromatase in... Biol Reprod 53:951-957, 1995.
- Evans TJ. The effects of bromocriptine, domperidone, and reserpine on circulating maternal levels of progestins, estrogens, and prolactin in pregnant... MS Thesis, UMC, 1996.
- Bao B,et. al. Changes in messenger RNA encoding 38-hydroxysteriod dehydrogenase/)5-)4 isomerase (38-HSD) during recruitment and... Serono Symposi.
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Progress 01/01/95 to 12/30/95
Outputs
Trichomoniasis, a venereal disease of cattle, was diagnosed in a large commercial farm in southern Missouri. Smegma samples from eighty-six bulls were cultured for the presence of Tritrichomonas foetus. Positive cultures were obtained from a total of 18 bulls. Of these, 28% (5/18) were positive on 3 weekly cultures, 55% (10/18) were positive on 2 cultures, and 17% (3/18) were positive on only one culture. These data demonstrate that repetitive culturing is necessary to detect chronically infected bulls, and that a commercial pouch culture system is an effective, convenient method of detecting T. foetus infections. This is the first reported diagnosis of an outbreak of trichomoniasis in Missouri cattle. Three bulls were purchased and experimentally infected with T. foetus. Preputial and penile cutaneous biopsies were taken before the bulls were infected and at intervals after infection. Work is in progress using an immunofluorescent stain coupled with a monoclonal
antibody in an attempt to develop a diagnostic test for infected bulls.
Impacts
(N/A)
Publications
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Progress 01/01/94 to 12/30/94
Outputs
The first recently-reported recovery of Tritrichomonas foetus in Missouri cattlewas in a 3500 head herd. After T. foetus was initially recovered from a sample of bulls, the entire bull battery was evaluated. All bulls were tested using preputial aspirates cultured in the BioMed InPouch(superscript TM) TF culture packs. Samples were collected weekly for three weeks, and resulted in 15 of 86, 8 of 85, and 12 of 86 successive positive cultures. These results confirm the necessity of repetitive samples to detect chronically infected bulls and the usefulness of the InPouch(superscript TM) culture system in the successful recovery of T. foetus. A control program was instituted and reproductive performance of the herd has returned to normal. Trichomoniasis was diagnosed in a second herd in the state after isolation of the organism from the prepuce of a bull. Both herds had a history of importation of bulls from states in the western United States. Preputial aspirates were
obtained from approximately 600 bulls presented to auction markets at selected geographic areas throughout the state and examined for the presence of T. foetus. Only one sample yielded a positive culture. Thus, the observations to date suggest that trichomoniasis is present in the state of Missouri but it does not appear to be widespread.
Impacts
(N/A)
Publications
- PLATA-MADRID, H., YOUNGQUIST, R.S., MURPHY, C.N., BENNETT-WIMBUSH, K., BRAUN, W.F., and LOCH, W.E. 1994. Ultrasonographic characteristics of the follicular and uterine dynamics in Belgian mares. J. Equine Vet. Sci. 14:412-423.
- YOUNGQUIST, R.S., GARVERICK, H.A., and KEISLER, D.H. 1995. Use of umbilical cord clamps in ovariectomies in cattle. J. Am. Vet. Med. Assoc. (in-press).
- JUENGEL, J.L., SMITH, G.W., SMITH, M.F., YOUNGQUIST, R.S., and GARVERICK, H.A. 1994. Pattern of protein production by bovine corpora lutea during luteolysis and characterization of expression of two major secretary products of regressing.
- PETER, D.A., FALES, W.H., MILLER, R.B., YOUNGQUIST, R.S., RANDLE, R.F., GANJAM, I.K., and LYBYER, J.L. 1995. Tritrichomonas foetus infection in a herd of Missouri cattle. J. Vet. Diagn. Invest. 7:xxx (in-press).
- XU, Z.Z., HAMILTON, S.A., SMITH, G.W., YOUNGQUIST, R.S., and GARVERICK, H.A. 1994. Expression of cytochrome P(subscript 450) 17(alpha)-hydroxylase (17(alpha)-H) and cytochrome P(subscript 450) aromatase (AROM) mRNAs in bovine follicles.
- KIEBORZ-LOOS, K.R., SMITH, M.F., KEISLER, D.H., YOUNGQUIST, R.S., HAMILTON, S.A., SALFEN, B.E., and GARVERICK, H.A. 1994. Oxytocin-induced release of prostaglandin F(subscript 2)(alpha) (PGF(subscript 2)(alpha)) in postpartum (PP) beef.
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