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Beachler TM, Bailey CS, McKelvey KA, Davis JL, Edwards A, Diaw M, Vasgaard JM, Whitacre MD. Haemoperitoneum in a pregnant mare with an ovarian haematoma. EQUINE VET EDUC 2014. [DOI: 10.1111/eve.12211] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- T. M. Beachler
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
| | - C. S. Bailey
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
| | - K. A. McKelvey
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
| | - J. L. Davis
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
| | - A. Edwards
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
| | - M. Diaw
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
| | - J. M. Vasgaard
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
| | - M. D. Whitacre
- College of Veterinary Medicine; North Carolina State University; Raleigh USA
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Sper RB, Whitacre MD, Bailey CS, Schramme AJ, Orellana DG, Ast CK, Vasgaard JM. Successful reduction of a monozygotic equine twin pregnancy via transabdominal ultrasound-guided cardiac puncture. EQUINE VET EDUC 2011. [DOI: 10.1111/j.2042-3292.2011.00254.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Schramme AR, Pinto CRF, Davis J, Whisnant CS, Whitacre MD. Pharmacokinetics of carbetocin, a long-acting oxytocin analogue, following intravenous administration in horses. Equine Vet J 2009; 40:658-61. [PMID: 19165935 DOI: 10.2746/042516408x334343] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASON FOR PERFORMING STUDY Current therapy protocols to treat persistent post mating endometritis and retained fetal membranes in mares typically include the administration of ecbolic drugs. Evaluation of the pharmacokinetics and tolerability of carbetocin, a long-acting oxytocin analogue, after i.v. administration is required. OBJECTIVES To determine the pharmacokinetic parameters (principally half-life) of carbetocin in horses. METHODS Five mature mares and one gelding received 0.175 mg carbetocin i.v. All animals were monitored periodically throughout the study for elevation in rectal temperature, heart rate, respiratory rate and signs of pain or discomfort. Plasma samples were collected for determination of carbetocin concentrations by radioimmunoassay. RESULTS Administration of carbetocin was well tolerated by all horses and its half-life was 17.2 min. CONCLUSIONS The half-life of carbetocin is greater than that previously reported for oxytocin (6.8 min). POTENTIAL RELEVANCE Carbetocin is an attractive alternative to oxytocin therapy in broodmare management.
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Affiliation(s)
- A R Schramme
- North Carolina State University, College of Veterinary Medicine, Department of Population Health and Pathobiology, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA
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Abstract
Mismating is one of the most frequently presented reproductive problems presented to veterinarians. Confirming whether or not a mismating has occurred is necessary to determine if therapy will be instituted. Detection of spermatozoa in the vagina is irrefutable evidence of copulation; however, absence of sperm in a vaginal cytology cannot rule out coitus. In order to improve detection of spermatozoa post-coitus, a prospective study was initiated utilizing natural breedings of purebred beagles.
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Affiliation(s)
- M. D. Whitacre
- College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC 2760
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Papich MG, Van Camp SD, Cole JA, Whitacre MD. Pharmacokinetics and endometrial tissue concentrations of enrofloxacin and the metabolite ciprofloxacin after i.v. administration of enrofloxacin to mares. J Vet Pharmacol Ther 2002; 25:343-50. [PMID: 12423224 DOI: 10.1046/j.1365-2885.2002.00434.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Enrofloxacin was administered i.v. to five adult mares at a dose of 5 mg/kg. After administration, blood and endometrial biopsy samples were collected at regular intervals for 24 h. The plasma and tissue samples were analyzed for enrofloxacin and the metabolite ciprofloxacin by high-pressure liquid chromatography. In plasma, enrofloxacin had a terminal half-life (t(1/2)), volume of distribution (area method), and systemic clearance of 6.7 +/- 2.9 h, 1.9 +/- 0.4 L/kg, and 3.7 +/- 1.4 mL/kg/min, respectively. Ciprofloxacin had a maximum plasma concentration (Cmax) of 0.28 +/- 0.09 microg/mL. In endometrial tissue, the enrofloxacin Cmax was 1.7 +/- 0.5 microg/g, and the t(1/2) was 7.8 +/- 3.7 h. Ciprofloxacin Cmax in tissues was 0.15 +/- 0.04 microg/g and the t(1/2) was 5.2 +/- 2.0 h. The tissue:plasma enrofloxacin concentration ratios (w/w:w/v) were 0.175 +/- 0.08 and 0.47 +/- 0.06 for Cmax and AUC, respectively. For ciprofloxacin, these values were 0.55 +/- 0.13 and 0.58 +/- 0.31, respectively. We concluded that plasma concentrations achieved after 5 mg/kg i.v. are high enough to meet surrogate markers for antibacterial activity (Cmax:MIC ratio, and AUC:MIC ratio) considered effective for most susceptible gram-negative bacteria. Endometrial tissue concentrations taken from the mares after dosing showed that enrofloxacin and ciprofloxacin both penetrate this tissue adequately after systemic administration and would attain concentrations high enough in the tissue fluids to treat infections of the endometrium caused by susceptible bacteria.
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Affiliation(s)
- M G Papich
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC 27606, USA.
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Cavalieri J, Farin PW, Kinder JE, Van Camp SD, Whitacre MD, Washburn SP, Britt JH. Ovarian follicular development following administration of progesterone or aspiration of ovarian follicles in Holstein cows. Theriogenology 2001; 55:805-21. [PMID: 11245267 DOI: 10.1016/s0093-691x(01)00445-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of this study was to compare the effects of administration of a single injection of progesterone (P4) and follicle aspiration on Day 7 of the estrous cycle on the timing and synchrony of follicular wave emergence, time of ovulation, and concentrations of P4, estradiol and FSH in Holstein cows. Twenty cows were assigned to 4 groups (n=5 cows per group) in a 2 by 2 factorial arrangement. Cows were treated on Day 7 (Day 0 = estrus) of the estrous cycle with either sham follicular aspiration and an oil vehicle administered intramuscularly (control), aspiration of ovarian follicles (aspiration), 200 mg of P4 im, or aspiration and 200 mg of P4 im (aspiration + P4). On Day 11, PGF(2alpha)(25mg) was administered to all groups. Synchrony of ovulation was less variable in each of the treatment groups compared with the control group (P<0.05), whereas ovulation was delayed in cows in the P4 group (P<0.05). Day of follicular wave emergence was delayed in the cows of the P4 group compared with cows in the aspiration and aspiration + P4 groups (P<0.01), whereas variability in wave emergence was less among both groups of aspirated cows compared with the cows in the control group (P<0.01). More follicles 4 to 7 mm in diameter were detected in the 2 aspiration groups compared with the cows in the control and P4 group (P<0.05). No difference was detected among groups in the maximum concentration of FSH associated with follicular wave emergence. We conclude that both the administration of P4 and the aspiration of follicles on Day 7 of the estrous cycle improves the synchrony of ovulation when luteolysis is induced on Day 11 and results in similar concentrations of FSH at the time of follicular wave emergence, but the timing of wave emergence and the number of follicles post-emergence differ.
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Affiliation(s)
- J Cavalieri
- Department of Farm Animal Health and Resource Management, North Carolina State University, Raleigh, USA
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Van Camp SD, Papich MG, Whitacre MD. Administration of ticarcillin in combination with clavulanic acid intravenously and intrauterinely to clinically normal oestrous mares. J Vet Pharmacol Ther 2000; 23:373-8. [PMID: 11168915 DOI: 10.1046/j.1365-2885.2000.00297.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ticarcillin and clavulanic acid (potassium clavulanate) were administered to normal oestrous mares intravenously (i.v.) at a dose of 50 and 1.67 mg/kg for ticarcillin and clavulanate, respectively. In a crossover design, the same drugs were administered intrauterine (i.u.) at a dose of 12.4 and 0.4 mg/kg for ticarcillin and clavulanate, respectively. The i.u. dose was administered in 100 mL of saline solution. Endometrial tissue biopsies and plasma samples were collected after drug administration for the determination of ticarcillin and clavulanate concentrations by high-pressure liquid chromatography and pharmacokinetic calculations. After i.u. administration both drugs were poorly absorbed into the plasma. The ticarcillin half-life from tissue and plasma was short after i.v. administration. Although concentrations in tissue were higher after i.u. administration than i.v., concentrations of ticarcillin declined rapidly, which would necessitate frequent treatment in order to maintain drug concentrations above the minimum inhibitory concentrations (MIC) throughout the treatment period. Clavulanate concentrations in tissue were either low or persisted for only a short time after administration via either route. It appears that addition of clavulanate to the formulation for treatment of i.u. infections in mares is of questionable value based on these concentrations.
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Affiliation(s)
- S D Van Camp
- North Carolina State University, College of Veterinary Medicine, Department of Farm Animal Health and Resource Management, 4700 Hillsborough Street, Raleigh, NC 27606, USA.
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Schoppee PD, Armstrong JD, Harvey RW, Whitacre MD, Felix A, Campbell RM. Immunization against growth hormone releasing factor or chronic feed restriction initiated at 3.5 months of age reduces ovarian response to pulsatile administration of gonadotropin-releasing hormone at 6 months of age and delays onset of puberty in heifers. Biol Reprod 1996; 55:87-98. [PMID: 8793063 DOI: 10.1095/biolreprod55.1.87] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A severe or moderate suppression of serum insulin-like growth factor I (IGF-I) was induced in heifers, beginning at 104 days of age, by active immunization against growth hormone-releasing factor (GRFi) or by chronic feed restriction (RES), respectively. We hypothesized that reduced serum IGF-I results in decreased serum estradiol-17 beta (E2), which in turn delays onset of puberty. The objectives of this experiment were to determine 1) whether GRFi and RES would alter follicular development and delay onset of puberty through similar mechanisms, and 2) whether GnRH would enhance follicular growth in control, GRFi, and RES heifers at 6 mo of age. Changes in IGF-I, somatotropin, LH, FSH, and E2 were evaluated. Serum IGF-I was greater in control than in RES heifers, and was greater in both these groups than in GRFi heifers by 169 days of age. Basal LH decreased in control and RES but not in GRFi heifers from 136 to 157 days of age. During the same period, a decrease in mean FSH was detected in control but not in GRFi and RES heifers. RES decreased mean serum E2 from 148 to 183 days of age. At 6 mo of age, pulsatile administration of GnRH (5 micrograms every 2 h for 42-46 h) increased serum LH and FSH similarly across treatments but had no effect on the number of follicles > or = 8 mm in GRFi and RES heifers relative to saline treatment. Serum E2 and IGF-I in follicular fluid from follicles > or = 8 mm were increased in all GnRH-treated heifers; however, concentrations of both hormones were lower in GRFi than in control or RES heifers. The main effect of treatments on serum IGF-I was reflected in follicles < or = 7 mm; follicular fluid IGF-I was greater in control than in RES heifers and was greater in both these groups than in GRFi heifers. Serum E2 was lower in RES than in control and GRFi heifers from 253 to 281 days of age. Because of an interaction, E2 was lower in GRFi-GnRH than in control-GnRH heifers but similar in GRFi-saline and control-saline heifers. By 393 days of age, 0% of RES and 32% of GRFi heifers had reached puberty compared to 71% of control heifers. These data support our hypothesis that decreased serum IGF-I results in decreased serum E2. GRFi appears to delay puberty in heifers because decreased serum IGF-I impairs the ovary's ability to synthesize preovulatory concentrations of E2, thereby delaying stimulation of an LH surge. In contrast, RES may delay puberty by delaying follicular development at two stages: a) decreased IGF-I in follicles < or = 7 mm may delay predominant follicular growth, and b) decreased LH may delay maturation of the preovulatory follicle.
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Affiliation(s)
- P D Schoppee
- Department of Animal Science, North Carolina State University, Raleigh 27695-7621, USA
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Cohick WS, Armstrong JD, Whitacre MD, Lucy MC, Harvey RW, Campbell RM. Ovarian expression of insulin-like growth factor-I (IGF-I), IGF binding proteins, and growth hormone (GH) receptor in heifers actively immunized against GH-releasing factors. Endocrinology 1996; 137:1670-7. [PMID: 8612500 DOI: 10.1210/endo.137.5.8612500] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Active immunization against GRF at 6 months of age delays puberty in beef heifers. The objectives of the present study were to determine whether active immunization against GRF at an earlier age would affect normal onset of puberty and follicular growth and to determine whether these changes were related to alterations in ovarian insulin-like growth factor I (IGF-I) or IGF binding protein (IG-FBP) messenger RNA (mRNA) levels. Heifers were immunized against human serum albumin (HSAi; n = 15) or against GRF conjugated to HSA (GRFi; n = 18) at 3 months of age. A third group of heifers was not immunized (CON; n = 16). Immunization against GRF delayed puberty beyond 13 months of age in 75% of treated heifers. Unilateral ovariectomy at 191 days of age revealed that the delay in puberty was associated with a reduction in the number of large ( > or = 7 mm in diameter) follicles. Large follicles were present in only 22% of GRFi heifers compared to 77% of HSAi heifers. The number of small ( < or = 3 mm in diameter) and medium (4 to 6 mm in diameter) follicles was not affected by GRFi. The percentage of 1- to 3-mm follicles that were atretic was not different between HSAi (65%) and GRFi (62%) heifers. Unilateral ovariectomy had no effect on age at puberty. Immunization against GRF decreased (P < 0.01) concentrations of IGF-I in serum (23 +/- 2 ng/ml) compared to HSAi heifers (109 +/- 11 ng/ml). IGF-I levels in follicular fluid (FFL) of medium and small follicles were also decreased by GRFi from 82 +/- 3 ng/ml in HSAi heifers to 48 +/- 6 ng/ml (P < 0.01). Levels of IGFBP-3 (determined by ligand blot analysis) in serum and FFL of small follicles were decreased by GRFi (P < 0.01). In contrast, IGFBP-2 serum levels were increased from 422 +/- 32 ng/ml in HSAi heifers to 657 +/- 6 ng/ml in GRFi heifers (P < 0.05). Likewise, IGFBP-2 levels in FFL from small and medium follicles were increased from 785 +/- 44 ng/ml to 926 +/- 44 ng/ml (P < 0.05). Ligand blot analysis indicated that IGFBP levels were lower in FFL from large vs. small follicles. The band intensities of IGFBP-4 and -5 were drastically reduced ( > 80%) while the decreases in IGFBP-2 and -3 were less marked ( < 50%). The decreased levels of IGFBP-5 in FFL from large follicles was not associated with an increase in proteolytic fragments detectable by immunoblot analysis. While mRNA transcripts for IGF-I, GH receptor, and IGFBP-2, -3, -4, and -5 were readily detectable in ovarian tissue, GRFi had no effect on ovarian levels of mRNA for each of these proteins. This suggests that the decrease in follicular development associated with GRFi may be related to changes in circulating IGF-I and/or IGFBPs.
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Affiliation(s)
- W S Cohick
- Department of Medicine, University of North Carolina School of Medicine, Chapel Hill 27599, USA
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Stanko RL, Cohick WS, Shaw DW, Harvey RW, Clemmons DR, Whitacre MD, Armstrong JD. Effect of somatotropin and/or equine chorionic gonadotropin on serum and follicular insulin-like growth factor I and insulin-like growth factor binding proteins in cattle. Biol Reprod 1994; 50:290-300. [PMID: 7511418 DOI: 10.1095/biolreprod50.2.290] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We investigated the effect of administration of somatotropin (ST) and/or eCG on insulin-like growth factor I (IGF-I) and IGF-binding proteins (IGFBP) in serum and follicular fluid (FFL) of cattle actively immunized against growth hormone-releasing factor (GRF). Cyclic beef cattle, previously immunized against GRF-(1-29)-Gly-Gly-Cys-NH2 conjugated to human serum albumin (synthesized and provided by Hoffmann-LaRoche, Inc., Nutley, NJ; GRFi, n = 31) or to human serum albumin alone (HSAi, n = 26), received (i.m.): 1) 25 mg recombinantly derived methionyl somatotropin (rbST, n = 14; sometribove provided by Monsanto Co., St. Louis, MO); 2) 1100 IU eCG (n = 10); 3) rbST and eCG (rbST-eCG, n = 15); or 4) vehicle (VEH, n = 17) at 0 and 24 h after receiving prostaglandin F2 alpha (PGF2 alpha). Serum samples were collected at 0 and 40 h after PGF2 alpha, and the ovary bearing the largest follicle (DOM) was removed 44.0 +/- 0.5 h after PGF2 alpha; FFL was harvested from DOM and the subordinate follicle (SUB). Before treatment (0 h), GRFi cows had lower serum ST (0.6 +/- 0.2 vs. 2.2 +/- 0.2 ng/ml; p < 0.01) and IGF-I (26 +/- 4 vs. 72 +/- 4 ng/ml; p < 0.01), but greater IGFBP-2 (594 +/- 48 vs. 384 +/- 52 ng/ml; p < 0.01) than HSAi cows. Serum and FFL concentrations of IGF-I or IGFBP-2 were not different between rbST- and rbST-eCG-treated cows or between VEH- and eCG-treated cows at Hour 40 after the initial treatment injection; therefore, data were combined and designated as rbST and VEH, respectively. Serum IGF-I was increased to a greater extent (percentage increase above 0 h) by rbST treatment in GRFi (362 +/- 24) than in HSAi (176 +/- 16) cows (immunization by treatment, p < 0.01). Across GRFi and HSAi, rbST lowered serum IGFBP-2 (342 +/- 31 vs. 541 +/- 27 ng/ml, rbST vs. VEH; p < 0.01). Diameters of DOM or SUB were not affected by immunization or treatment. Concentrations of IGF-I and IGFBP-3 (determined by ligand blot analysis) in FFL from both DOM and SUB were lower (p < 0.05) in GRFi than in HSAi cows. In contrast, IGFBP-2 in FFL was elevated in SUB, but not DOM, in GRFi compared to HSAi cows.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- R L Stanko
- Department of Animal Science, North Carolina State University, Raleigh 27695-7621
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Armstrong JD, Stanko RL, Cohick WS, Simpson RB, Harvey RW, Huff BG, Clemmons DR, Whitacre MD, Campbell RM, Heimer EP. Endocrine events prior to puberty in heifers: role of somatotropin, insulin-like growth factor-I and insulin-like growth factor binding proteins. J Physiol Pharmacol 1992; 43:179-93. [PMID: 1285340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We have utilized active immunization against growth hormone releasing factor (GRF) to investigate relationships among somatotropin (ST), insulin-like growth factor-I (IGF-I), IGF binding proteins (IGFBP) and ovarian function in heifers. Active immunization against GRF (GRFi) has been demonstrated to abolish episodic release of ST and decrease serum concentrations of IGF-I. In initial experiments investigating onset of puberty, breeds of heifers differing in growth rate and reproductive traits (Angus, Charolais and Simmental) were immunized against GRF or served as controls (immunized against carrier protein, human serum albumin, HSAi). GRFi decreased rate of muscle and skeletal growth, but increased deposition of adipose tissue. In Angus and Charolais, but not Simmental heifers, GRFi at 6 mo of age significantly delayed onset of puberty beyond 18 mo of age. Retrospective analyses of serum IGF-I revealed that GRFi heifers reaching puberty at a normal age had greater pre-treatment (6 mo of age) IGF-I than GRFi heifers in which puberty was delayed. Collectively, these results strongly indicate that the bovine hypothalamic-hypophyseal-ovarian axis is particularly sensitive to changes in metabolism at or near 6 mo of age. Another series of experiments tested the hypothesis that lowering serum IGF-I via GRFi initially at 3 mo of age would increase the percentage of Angus and Simmental heifers not reaching puberty. Three mo old Angus and Simmental heifers were assigned to GRFi (n = 18), HSAi (n = 14) or received no treatment (controls, n = 16). HSAi and GRFi heifers were unilaterally ovariectomized (ULO) at 6 mo of age. As anticipated, GRFi at a younger age increased percentage of heifers not reaching puberty; over 75% of control and HSAi heifers reached puberty by 14 mo of age compared to 22% of GRFi heifers. Serum and follicular fluid (FFL; follicles < or = 4 mm) concentrations of IGF-I were suppressed by GRFi. Serum, but not FFL concentrations of IGF binding protein-2 (IGFBP-2) were greater in GRFi than in HSAi heifers. GRFi delayed puberty apparently by suppressing follicular growth because number of follicles < or = 7 mm was significantly lower in GRFi than in HSAi heifers. In conclusion, active immunization against GRF at 3 or 6 months of age delays puberty in beef heifers. Delayed puberty was preceded by suppression of follicular growth, and decreased concentrations of IGF-I in serum and follicular fluid.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- J D Armstrong
- Department of Animal Science, College of Agriculture and Life Sciences, North Carolina State University, Raleigh
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Abstract
A vaginal septum was diagnosed in an English bulldog bitch during routine estrous cycle staging. The septum extended 16 cm from the vestibulo-vaginal junction to just caudal to the cervix. The septum was removed by two applications of an Nd:YAG laser via a flexible fiberoptic endoscope. Complete healing occurred over a 5-week period and was uneventful. The bitch was bred and subsequently delivered four puppies vaginally. Transendoscopic laser ablation provided a noninvasive approach to surgically remove a vaginal septum in the dog.
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Affiliation(s)
- M D Whitacre
- Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606
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Wichtel JJ, Whitacre MD, Yates DJ, Van Camp SD. Comparison of the effects of PGF2α and bromocryptine in pregnant beagle bitches. Theriogenology 1990; 33:829-36. [PMID: 16726779 DOI: 10.1016/0093-691x(90)90818-e] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/1989] [Accepted: 01/17/1990] [Indexed: 10/26/2022]
Abstract
Termination of pregnancy (abortion) was successful in four of four bitches that received PGF(2)alpha (125 mug/kg bid s.c.) and in two or four bitches that received bromocryptine (62.5 mug/kg bid po) for up to 6 d beginning 43 to 45 d post ovulation. Four sham-treated controls whelped normally at term. The incidence of side effects, primarily emesis and loose stools, was similar for both experimental groups. Bitches that failed to abort following treatment with bromocryptine whelped normally at term.
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Affiliation(s)
- J J Wichtel
- Department of Food Animal and Equine Medicine College of Veterinary Medicine North Carolina State University. Raleigh, NC 27606 USA
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Van Camp SD, Mahler J, Roberts MC, Tate LP, Whitacre MD. Primary ovarian adenocarcinoma associated with teratomatous elements in a mare. J Am Vet Med Assoc 1989; 194:1728-30. [PMID: 2753798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
An ovarian adenocarcinoma with teratomatous elements was removed from a 9-year-old mare. Although no other lesions were detected at ovariectomy, multifocal metastatic masses led to cachexia and euthanasia 2 months later. This case reaffirms the need to exercise caution when removing ovarian masses to prevent seeding of the abdomen. This report includes discussion of the WHO system of classification of ovarian tumors.
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Affiliation(s)
- S D Van Camp
- Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606
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Whitacre MD, Van Camp SD, Maclachlan NJ, Umstead JA. Premature lactation in a heifer with a sex cord-stromal tumor. J Am Vet Med Assoc 1988; 193:946-8. [PMID: 3192476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A tumor of the ovary was believed to be responsible for initiating lactation in a nonpregnant heifer. The only abnormal clinical sign was milk secretion from all 4 mammary glands and a large mass in the abdomen. Concentrations of estrogen and progesterone were markedly high. The mass was removed and identified as a sex cord-stromal tumor with a granulosa cell pattern.
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Affiliation(s)
- M D Whitacre
- Department of Food Animal and Equine Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh NC 27606
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Abstract
Artificial insemination is an effective technique for improving utilization of the stallion while maintaining normal conception rates in the mare. However, procedures for collection, evaluation, and insemination of semen must be followed carefully to achieve good results. Techniques for preservation of equine semen in the liquid or frozen state could potentially allow for more widespread use of genetically superior stallions. Further acceptance of artificial insemination and the use of cooled or frozen transported semen by breed registries is needed before this will occur. More work is needed to perfect methods of semen preservation, even though semen from some stallions can be cooled or frozen quite successfully at the present time.
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Affiliation(s)
- D J Yates
- Department of Food Animal and Equine Medicine, North Carolina State University College of Veterinary Medicine, Raleigh
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Affiliation(s)
- J M Cullen
- Department of Microbiology, Parasitology and Pathology, School of Veterinary Medicine, Raleigh, NC 27606
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Brown TT, Whitacre MD, Robison OW. Use of an inactivated vaccine for prevention of parvovirus-induced reproductive failure in gilts. J Am Vet Med Assoc 1987; 190:179-81. [PMID: 3028999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Gilts from dams that had been inoculated with inactivated porcine parvovirus (PPV) vaccine before breeding became seronegative to PPV by 26 weeks of age. Vaccination of these gilts with inactivated PPV vaccine at 32 weeks of age resulted in an antibody response that peaked at about 2 weeks after vaccination, with -log10 mean hemagglutination inhibiting (HI) antibody titers of less than 2. In the first-year group (82 gilts), HI titers gradually decreased, 20% of the gilts being seronegative by 6 to 7 weeks after vaccination and 75% being seronegative by 16 weeks after vaccination. In the second-year group, 93 gilts were infected naturally by a field strain of PPV at about 11 weeks after single vaccination with inactivated PPV. Additionally, in the second year, 20 vaccinated and 6 nonvaccinated gilts were immune-challenged with virulent PPV at 10 to 12 weeks after vaccination. Neither field nor challenge PPV infection of vaccinated pregnant gilts caused reproductive failure, even though some of the gilts became seronegative for PPV before challenge. Our findings suggest that single vaccination of gilts with inactivated PPV vaccine should give adequate protection from PPV-induced reproductive failure, even though serum HI titers decrease to an undetectable level shortly before PPV infection.
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Abstract
The objective was to determine factors that affect the expression of estrus. Thirteen lactating Holstein cows were ovariectomized about 4 to 6 wk postpartum and then challenged repeatedly with progesterone and estradiol benzoate to induce estrus six times during the postpartum period. Each challenge included 5 d when the cow was primed with progesterone through insertion of a progesterone-impregnated, foam rubber pessary. Estradiol benzoate (1 mg) was injected intramuscularly 36 h after removal of the pessary. Groups of two to three cows each began the experiment at 3-mo intervals to avoid confounding treated simultaneously. Observations for estrous behavior were at 8-h intervals following each challenge. A minimum of three sexually active cows were always observed together to avoid differences in estrous behavior caused by having too few sexually active animals in the group. Observations for estrous behavior were at 8-h intervals following each challenge. During each observation, cows were observed for 30 min on dirt and for 30 min on concrete. Standing behavior was not influenced by postpartum interval, season of year, or milk yield. Mounting behavior increased from the first to the sixth postpartum challenge, but it was not affected by season of year or milk yield. Duration of estrus, mounting activity, and standing activity were greater on dirt than on concrete. These results indicate that the surface on which cows were observed had a profound effect on sexual behavior; however, postpartum interval, season of year, and milk yield were of minor importance.
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Froetschel MA, Croom WJ, Gaskins HR, Leonard ES, Whitacre MD. Effects of avoparcin on ruminal propionate production and amino acid degradation in sheep fed high and low fiber diets. J Nutr 1983; 113:1355-62. [PMID: 6306185 DOI: 10.1093/jn/113.7.1355] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The effect of the antibiotic, avoparcin, on ruminal propionate production and amino acid degradation was investigated by using four rumen fistulated wethers. Wethers were fed each of four diets during 28-day periods in a 4 X 4 Latin square design. Diets were high fiber (HF), high fiber plus 50 ppm avoparcin (HF-AVO), low fiber (LF) and low fiber plus 50 ppm avoparcin (LF-AVO). Total digestible energy intake (1.25 X maintenance) and crude protein intake for each animal were similar for all diets. Propionate production was determined each period from all animals by using a single injection of [1-14C]propionate and polyethylene glycol. Avoparcin decreased total volatile fatty acid concentration, increased ruminal pH and molar proportions of propionate on both HF and LF diets. Daily propionate production and pool turnover rate increased in sheep fed LF-AVO. Similar changes were noted in HF-AVO animals, although they were not statistically significant. Avoparcin decreased ruminal ammonia (50 vs. 45 mg/100 ml) and increased alpha amino nitrogen (8.6 vs. 14.3 mM) in LF-fed sheep. In vitro studies demonstrated a decreased degradation of crystalline amino acids by mixed populations of rumen microorganisms from sheep receiving LF diets containing avoparcin. Avoparcin appears to modify rumen fermentation by increasing propionate production and inhibiting protein or amino acid degradation.
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Whitacre MD, Threlfall WR. Effects of ergocryptine on plasma prolactin, luteinizing hormone, and progesterone in the periparturient sow. Am J Vet Res 1981; 42:1538-41. [PMID: 6895686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Effects of ergocryptine (ERG) on the periparturient sow were assessed by measuring changes in prolactin, luteinizing hormone, and progesterone in plasma. Hormones in plasma were determined on samples collected daily from 21 days before parturition until postpartum day (PPD) 21. Administration of ERG completely blocked the initiation of lactation and prevented the surge in prolactin that occurred just before parturition, as compared with effects in control sows. The gestation period was shorter (P less than 0.01) in ERG-treated sows compared with the gestation period in controls. Although the number of pigs farrowed was not different between treated and control sows, the ERG-treated sows did not raise any pigs to PPD 21. Luteinizing hormone concentrations were higher (P less than 0.01) from 10 days before parturition until PPD 21, but plasma progesterone concentrations were not different in treated sows when compared with concentrations in control sows.
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