Analyze Diet

Topic:Reproduction

Reproduction in horses encompasses the biological processes and mechanisms involved in the breeding and development of equine offspring. This includes the study of reproductive anatomy, physiology, and endocrinology in both mares and stallions. Key areas of interest include the estrous cycle, ovulation, conception, gestation, and parturition. Researchers also examine factors influencing fertility, reproductive technologies such as artificial insemination and embryo transfer, and management practices that impact reproductive success. This page compiles peer-reviewed research studies and scholarly articles that explore the physiological, genetic, and environmental aspects of equine reproduction.
[The castration of a stallion; past, present and future].
Tijdschrift voor diergeneeskunde    June 9, 2005   Volume 130, Issue 10 312-317 
van der Velden MA.No abstract available
Assessment of the cryopreservation of equine spermatozoa in the presence of enzyme scavengers and antioxidants.
American journal of veterinary research    June 7, 2005   Volume 66, Issue 5 772-779 doi: 10.2460/ajvr.2005.66.772
Baumber J, Ball BA, Linfor JJ.To evaluate the effect of the addition of enzyme scavengers and antioxidants to the cryopreservation extender on characteristics of equine spermatozoa after freezing and thawing. Methods: 2 ejaculates collected from each of 5 stallions. Methods: Equine spermatozoa were cryopreserved in freezing extender alone (control samples) or with the addition of catalase (200 U/mL), superoxide dismutase (200 U/mL), reduced glutathione (10 mM), ascorbic acid (10 mM), alpha-tocopherol (25, 50, 100, or 500 microM or 1 mM), or the vehicle for alpha-tocopherol (0.5% ethanol). After thawing, spermatozoal motili...
Effect of cryopreservation on the cellular integrity of equine embryos.
Reproduction (Cambridge, England)    June 1, 2005   Volume 129, Issue 6 789-798 doi: 10.1530/rep.1.00622
Tharasanit T, Colenbrander B, Stout TA.Horse embryos are rarely cryopreserved in practice because expanded blastocysts tolerate freezing poorly, and the embryo begins expanding very soon after entering the uterine cavity. This study examined the effects of freezing on cytoskeleton integrity, and investigated whether cell damage could be reduced using trypsin to thin the blastocyst capsule or cytochalasin-B (cyto-B) to stabilise the cytoskeleton. Sixty-nine embryos were recovered 7 days after ovulation and equilibrated in 10% glycerol, with or without pretreatment with 0.2% trypsin or 7.5 microg/ml cyto-B. Forty-two of the embryos w...
Advanced fertility diagnosis in stallion semen using transmission electron microscopy.
Animal reproduction science    May 31, 2005   Volume 91, Issue 3-4 285-298 doi: 10.1016/j.anireprosci.2005.04.004
Pesch S, Bostedt H, Failing K, Bergmann M.Routine semen analysis of stallions is based on light microscopy (LM). However, there are still a number of animals that are subfertile or even infertile not being identified with conventional semen analysis. The objective of this study was to investigate the suitability of transmission electron microscopy (TEM) for advanced fertility diagnosis in stallion. We examined ejaculates of 46 stallions with known fertility. Animals were divided into three different groups: group 1, fertile stallions (pregnant mares> or =70%, n=29); group 2, subfertile stallions (pregnant mares 10-69%, n=14); group 3,...
Effect of alpha-tocopherol and tocopherol succinate on lipid peroxidation in equine spermatozoa.
Animal reproduction science    May 25, 2005   Volume 87, Issue 3-4 321-337 doi: 10.1016/j.anireprosci.2004.12.004
Almeida J, Ball BA.The objective of this study was to compare the effect of alpha-tocopherol and its ester, alpha tocopherol succinate, on lipid peroxidation and motility of equine spermatozoa. In experiment one, spermatozoa were incubated with dl-alpha-tocopherol (5, 25, 100 or 500 microM), DL-alpha tocopherol succinate (5, 25, 100 or 500 microM) or vehicle (0.5% ethanol) at 38 degrees C, and sperm motility was determined at 30, 60 and 120 min. In experiment two, spermatozoa loaded with the lipophilic probe, C11BODIPY(581/591), were incubated with dl-alpha-tocopherol (50 and 100 microM), DL-alpha-tocopherol suc...
Effect of seminal plasma on the cryopreservation of equine spermatozoa.
Theriogenology    May 25, 2005   Volume 63, Issue 9 2372-2381 doi: 10.1016/j.theriogenology.2004.05.032
Moore AI, Squires EL, Graham JK.Seminal plasma is generally removed from equine spermatozoa prior to cryopreservation. Two experiments were designed to determine if adding seminal plasma back to spermatozoa, prior to cryopreservation, would benefit the spermatozoa. Experiment 1 determined if different concentrations of seminal plasma affected post-thaw sperm motility, viability and acrosomal integrity of frozen/thawed stallion spermatozoa. Semen was washed through 15% Percoll to remove seminal plasma and spermatozoa resuspended to 350 x 10(6)sperm/mL in a clear Hepes buffered diluent containing either 0, 5, 10, 20, 40 or 80%...
Equine hemi-castration: review of the condition, prevalence, aetiology, diagnosis and surgical management.
Australian veterinary journal    May 24, 2005   Volume 83, Issue 4 203-207 doi: 10.1111/j.1751-0813.2005.tb11648.x
Maxwell JA.No abstract available
Theriogenology question of the month. Seminoma, spermatocele, sustentacular cell tumor.
Journal of the American Veterinary Medical Association    May 24, 2005   Volume 226, Issue 10 1649-1650 doi: 10.2460/javma.2005.226.1649
Threlfall WR, Robertson JT, Munsterman AS, Oglesbee MJ, Hubbell JA.No abstract available
Transcervical endoscope-guided emptying of a transmural uterine cyst in a mare.
The Veterinary record    May 24, 2005   Volume 156, Issue 21 679-682 doi: 10.1136/vr.156.21.679
Rambags BP, Stout TA.An 18-year-old Friesian mare with a large intrauterine cyst was examined by transrectal ultrasonography. There were several small to moderately sized intraluminal endometrial cysts, one of which connected via the myometrium to a large subserosal cyst, thereby effectively forming a 'transmural' cyst complex. During a videohysteroscopy, the intraluminal part of this transmural cyst was removed by electrocoagulation via a polypectomy snare. It was then possible to drain the large subserosal part of the cyst into the uterine lumen by transrectal massage, thereby confirming the presence of the tran...
In vitro comparisons of two cryopreservation techniques for equine embryos: slow-cooling and open pulled straw (OPS) vitrification.
Theriogenology    May 24, 2005   Volume 64, Issue 7 1619-1632 doi: 10.1016/j.theriogenology.2005.04.001
Moussa M, Bersinger I, Doligez P, Guignot F, Duchamp G, Vidament M, Mermillod P, Bruyas JF.Vitrification using open pulled straw (OPS) has provided encouraging results with embryos from other species. The aim of this study was to compare the survival of 6.5- and 6.75-day-old equine embryos after OPS vitrification and slow-cooling. Eighteen embryos were frozen using a slow-cooling method. Embryos were placed in modified PBS with increasing glycerol concentration (2.5%, 5%, 7.5% and 10% (v/v) 5 min each). Embryos were loaded into 0.25 ml straws then placed in a programmable freezer and subsequently plunged into liquid nitrogen. After thawing, cryoprotectant was removed by five steps w...
Comparison of cell proliferation index in equine and caprine embryos using a modified BrdU incorporation assay.
Theriogenology    May 24, 2005   Volume 64, Issue 8 1823-1832 doi: 10.1016/j.theriogenology.2005.04.016
The measurement of cell proliferation and cell viability using 5'bromo-2'deoxy-uridine (BrdU) labelling has been described in several cell types and species. The aim of this study was to adapt this technique to equine embryos and to compare the index of DNA replication (S-phase) between equine and caprine embryos. Seventeen equine embryos were recovered at day 6.5 post-ovulation and 20 caprine embryos were recovered at day 7 after the onset of estrus. Equine embryos were incubated during 1h at 39 degrees C in PBS containing 1mM of BrdU. Embryos were then treated in 0.05% trypsin during 15 min ...
Estrous cycle stage-independent treatment of PMSG and hCG can induce superovulation in adult Wistar-Imamichi rats.
Experimental animals    May 18, 2005   Volume 54, Issue 2 185-187 doi: 10.1538/expanim.54.185
Kon H, Tohei A, Hokao R, Shinoda M.The estrous cycle influence on the number of ovulated eggs after injection of pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) was investigated in 12, 18, and 24 weeks old adult female Wistar-Imamichi (WI) rats. PMSG (150 IU/kg) was injected at metestrus, diestrus, proestrus, or estrus, followed by hCG (75 IU/kg) 55 h later. Ovulation was induced at all ages and stages of the estrous cycle. The number of ovulated eggs was not affected by stage for similarly aged rats, however, the number of ovulated eggs obtained after treatment decreased with age. These results d...
Immunoexpression of androgen receptors in the reproductive tract of the stallion.
Annals of the New York Academy of Sciences    May 14, 2005   Volume 1040 227-229 doi: 10.1196/annals.1327.030
Bilinska B, Hejmej A, Gancarczyk M, Sadowska J.The objective of this study was to visualize androgen receptors (ARs) in the testis, epididymis, and prostate of the stallion by means of immunohistochemistry. Nuclear immunostaining was found in all somatic cells in the testis--Leydig, Sertoli, and peritubular myoid cells; in both types of epithelial cells of the epididymis; and in the secretory cells of the prostate. These results indicate that ARs are distributed throughout the reproductive tract cells of the stallion.
Changes in the heart rate and plasma epinephrine and norepinephrine concentrations of the stallion during copulation.
Reproductive medicine and biology    May 3, 2005   Volume 4, Issue 2 143-147 doi: 10.1111/j.1447-0578.2005.00093.x
Terada M, Momozawa Y, Komano M, Kusunose R, Sato F, Saito TR. The physiological indexes of the copulatory behavior of the stallion have not been investigated in detail and may differ from those of other species, such as humans and rats. In order to understand the breeding capability of various stallions, their behavior during copulation was observed, and heart rate (HR) and the plasma concentrations of norepinephrine (NA) and epinephrine (Ad) were measured sequentially for a total of 13 copulations carried out during 2 days. The mean HR at rest was 35.3 ± 0.9 beats per minute (b.p.m.) and it peaked during mounting (162.1 ± 5.4 b.p.m.). The HR a...
Expression of mRNA encoding insulin-like growth factor binding protein-2 (IGFBP-2) during induced and natural regression of equine corpora lutea.
Theriogenology    April 25, 2005   Volume 64, Issue 6 1371-1380 doi: 10.1016/j.theriogenology.2005.02.015
Watson ED, Bae SE, Al-Zi'abi MO, Hogg CO, Armstrong DG.The insulin-like growth factors, IGF-I and -II, have been shown to play a key role in luteal function in some species. The IGF binding proteins, IGFBP-2 and -3, have been shown to inhibit binding of IGF-I and -II to bovine luteal cells and decrease progesterone production. We have recently shown that equine follicles have the genetic capacity to produce IGFBP-2, and that levels decrease in healthy preovulatory follicles. In the present study expression of mRNAs encoding IGFBP-2, as well as the rate-limiting steroidogenic enzyme, P450scc, were studied in equine corpora lutea to investigate whet...
Expression of aromatase and oestrogen receptors in reproductive tissues of the stallion and a single cryptorchid visualised by means of immunohistochemistry.
Domestic animal endocrinology    April 19, 2005   Volume 29, Issue 3 534-547 doi: 10.1016/j.domaniend.2005.03.002
Hejmej A, Gorazd M, Kosiniak-Kamysz K, Wiszniewska B, Sadowska J, Bilińska B.Androgen metabolism may proceed to amplify the action of testosterone by its aromatisation to oestradiol. Recently, a growing body of evidence suggests a role of oestrogens in the male reproductive tract via their specific oestrogen receptors (ERs). In order to check whether androgens are converted to oestrogens in the testis, epididymis and prostate of the stallion, the expression of aromatase was visualised by means of immunohistochemistry. Moreover, to show the cellular targets for oestrogens the presence of oestrogen receptor alpha (ERalpha) and oestrogen receptor beta (ERbeta) was demonst...
Nitric oxide levels and nitric oxide synthase expression in uterine samples from mares susceptible and resistant to persistent breeding-induced endometritis.
American journal of reproductive immunology (New York, N.Y. : 1989)    April 19, 2005   Volume 53, Issue 5 230-237 doi: 10.1111/j.1600-0897.2005.00270.x
Alghamdi AS, Foster DN, Carlson CS, Troedsson MH.Breeding-induced endometritis (BIE) in the mare is resolved by 36 hr after insemination in resistant mares. However, 10-15% susceptible broodmares fail to do so because of impaired uterine contractility between 7 and 19 hr after exposure to seminal or bacterial challenge, which reduces their fertility. Methods: Nitric oxide (NO) in uterine secretions, and expression of nitric oxide synthase (NOS) in uterine biopsies were compared between susceptible and resistant groups 13 hr after insemination. Results: Susceptible mares had a higher NO in their uterine secretions and greater inducible NOS (i...
Dopamine receptors in equine ovarian tissues.
Domestic animal endocrinology    April 14, 2005   Volume 28, Issue 4 405-415 doi: 10.1016/j.domaniend.2005.02.001
King SS, Campbell AG, Dille EA, Roser JF, Murphy LL, Jones KL.Dopamine (DA) agonist and antagonist treatments can affect ovarian reproductive events in the mare. To support our theory that DA produces these effects by acting directly on the ovary, we analyzed equine ovarian tissues for the presence of dopamine receptor-1 (D1r) and dopamine receptor-2 (D2r) mRNA by reverse transcription polymerase chain reaction (RT-PCR) and D1r and D2r proteins by Western blot and immunohistochemistry (IHC). RT-PCR was performed on RNA isolated from ovarian cortex, medulla, granulosa/theca or corpus luteum (CL) tissues and from pituitary (D2r control) and renal artery (D...
LH and IGF-1 release during oestrus and early luteal phase in lactating and non-lactating horse mares.
Animal reproduction science    April 14, 2005   Volume 91, Issue 1-2 97-106 doi: 10.1016/j.anireprosci.2005.03.002
Deichsel K, Aurich J, Parvizi N, Bruckmaier RM, Aurich C.The aim of the present study was to determine effects of lactation on basal LH and IGF-1 concentrations and on the LH response to a GnRH-analogue at different stages of the oestrous cycle in mares. A total of 17 cyclic Haflinger mares were included in the study. Experiments were performed on lactating mares in first postpartum oestrus, the subsequent early luteal phase, and second postpartum oestrus. Non-lactating mares were used in oestrus and early luteal phase. Blood samples were taken for 1 h at 15 min intervals. Mares were then injected with the GnRH-analogue buserelin (GnRHa; 5 microg i....
Regulation of circulating gonadotropins by the negative effects of ovarian hormones in mares.
Biology of reproduction    April 13, 2005   Volume 73, Issue 2 315-323 doi: 10.1095/biolreprod.105.040253
Ginther OJ, Gastal EL, Gastal MO, Beg MA.The functional and temporal relationships between circulating gonadotropins and ovarian hormones in mares during Days 7-27 (ovulation = Day 0) was studied using control, follicle ablation, and ovariectomy groups (n = 6 mares/group). In the follicle-ablation group, all follicles > or = 6 mm were ablated on Day 7, and every 2 days thereafter, newly emerging follicles were also ablated. Estradiol concentrations decreased (P < 0.01) similarly in the controls and the follicle-ablation group between Days 7 and 11 and by Day 15 began to increase in the controls and continued to decrease in the ...
Inheritance of hereditary equine regional dermal asthenia in Quarter Horses.
American journal of veterinary research    April 13, 2005   Volume 66, Issue 3 437-442 doi: 10.2460/ajvr.2005.66.437
Tryon RC, White SD, Famula TR, Schultheiss PC, Hamar DW, Bannasch DL.To assess heritability and mode of inheritance for hereditary equine regional dermal asthenia (HERDA) in Quarter Horses. Methods: 1,295 horses with Quarter Horse bloodlines, including 58 horses affected with HERDA. Methods: Horses were classified as affected or unaffected or as undetermined when data were insufficient to assess phenotype. Pedigree data were analyzed to determine the probable mode of inheritance. Heritability was estimated by use of Bayesian statistical methods. Results: Heritability (mean+/-SD) of HERDA was estimated to be 0.38+/-0.13, with both sexes having an equal probabili...
Acute insulin-induced hypoglycaemia does not alter IGF-1 and LH release in cyclic mares.
Reproduction in domestic animals = Zuchthygiene    April 12, 2005   Volume 40, Issue 2 117-122 doi: 10.1111/j.1439-0531.2005.00564.x
Deichsel K, Hoppen HO, Bruckmaier R, Kolm G, Aurich C.Lactation in the mare is associated with changes in the release of metabolic as well as reproductive hormones. Plasma glucose concentration is constantly reduced in lactating compared with non-lactating mares. Several metabolic signals have been proposed to link nutrition and somatic metabolism with reproductive function. The following experiment was performed to study the effect of acute hypoglycaemia on the release of insulin-like growth factor-1 (IGF-1) and luteinizing hormone (LH) in cyclic mares. Different doses of insulin (0.1 and 0.2 IU/kg body weight) were given to induce a decrease in...
The early conception factor (ECF) lateral flow assay for non-pregnancy determination in the mare.
Theriogenology    April 7, 2005   Volume 64, Issue 5 1061-1071 doi: 10.1016/j.theriogenology.2005.02.012
Horteloup MP, Threlfall WR, Funk JA.The horse early conception factor (ECF) test is designed for qualitative determination of the ECF glycoprotein in the mare that has conceived. The objectives of this study were to determine the performance of the horse ECF test for the detection of the non-pregnant mare, and to determine the agreement among subjects or "readers" regarding the interpretation of the test. Blood samples from 60 mares were collected on Days 0, 5, 8, 11 and 18 following ovulation. Pregnancy status diagnosed with the ECF test was compared (2 x 2 table) to pregnancy status diagnosed by palpation per rectum and ultras...
Follicular fluid concentrations of free insulin-like growth factor (IGF)-I during follicular development in mares.
Domestic animal endocrinology    April 7, 2005   Volume 29, Issue 4 573-581 doi: 10.1016/j.domaniend.2005.03.003
Spicer LJ, Santiago CA, Davidson TR, Bridges TS, Chamberlain CS.The objective of the present study was to evaluate changes in concentrations of free insulin-like growth factor (IGF)-I in follicular fluid (FFL) during follicle development in the mare. Mares (n = 14) were classified as either in the follicular phase (n = 8) or luteal phase (n = 6). Follicles (n = 92) were categorized as small (6-15 mm; n = 54), medium (16-25 mm; n = 23) or large (>25 mm; n = 15) and FFL was collected. Free IGF-I levels in FFL in large follicles of follicular phase mares were greater (P < 0.05) than in large follicles of luteal phase mares and small or medium follicles ...
Application of MTT reduction assay to evaluate equine sperm viability.
Theriogenology    April 2, 2005   Volume 64, Issue 6 1350-1356 doi: 10.1016/j.theriogenology.2005.02.009
Aziz DM, Ahlswede L, Enbergs H.The assay of MTT reduction depends on the ability of metabolically active cells to reduce the tetrazolium salt (3[4,5-dimethylthiazol-2-y1]-2,5-diphenyltetrazolium bromide) to formazan. This study was conducted to examine and validate of a simple and less costly MTT test in determining equine sperm viability and compare the efficiency of this test with a flow cytometer. Fresh ejaculates from 11 stallions (warm blood) were included in this study. Semen was diluted to 100 million cells/ml in a Hepes 0.1% BSA. The rates of MTT reduction were measured in microtiter plates after incubation for 1 an...
[Horse Advisory Committee: ‘newborn foal’].
Tijdschrift voor diergeneeskunde    March 31, 2005   Volume 130, Issue 6 177-179 
Wesselink HG, Sloet van Oldruitenborgh-Oosterbaan MM.No abstract available
[Horse Advisory Committee: ‘Sperm handling’].
Tijdschrift voor diergeneeskunde    March 31, 2005   Volume 130, Issue 6 179-181 
Stout TA, Seuren-Coppens ML, Parlevliet JM, Colenbrander B.No abstract available
In vivo effects of pregnancy-associated plasma protein-A, activin-A and vascular endothelial growth factor on other follicular-fluid factors during follicle deviation in mares.
Reproduction (Cambridge, England)    March 31, 2005   Volume 129, Issue 4 489-496 doi: 10.1530/rep.1.00555
Ginther OJ, Gastal EL, Gastal MO, Beg MA.During a follicular wave in mares, the two largest follicles (F1 and F2) begin to deviate in diameter when F1 is a mean of 22.5 mm. The intrafollicular effects of pregnancy-associated plasma protein-A (PAPP-A), IGF-I, activin-A and vascular endothelial growth factor (VEGF) on other follicular-fluid factors during deviation were studied. In four treated groups (n = 7/group), a single dose of one of the four factors was injected into F2 when F1 was > or = 20.0 mm (expected beginning of deviation). In a control group (n = 7), F2 was injected with vehicle. One day after treatment, a sample of f...
Theriogenology question of the month. Endometrial cups.
Journal of the American Veterinary Medical Association    March 25, 2005   Volume 226, Issue 6 877-879 doi: 10.2460/javma.2005.226.877
Willis LA, Riddle WT.No abstract available
Genetic diagnosis of sex chromosome aberrations in horses based on parentage test by microsatellite DNA and analysis of X- and Y-linked markers.
Equine veterinary journal    March 23, 2005   Volume 37, Issue 2 143-147 doi: 10.2746/0425164054223787
Kakoi H, Hirota K, Gawahara H, Kurosawa M, Kuwajima M.Sex chromosome aberrations are often associated with clinical signs that affect equine health and reproduction. However, abnormal manifestation with sex chromosome aberration usually appears at maturity and potential disorders may be suspected infrequently. A reliable survey at an early stage is therefore required. Objective: To detect and characterise sex chromosome aberrations in newborn foals by the parentage test and analysis using X- and Y-linked markers. Methods: We conducted a genetic diagnosis combined with a parentage test by microsatellite DNA and analysis of X- and Y-linked genetic ...