Prostaglandins are lipid compounds derived from fatty acids that are present in various tissues of horses. They are involved in a wide range of physiological processes, including the regulation of inflammation, blood flow, and reproductive functions. In equine medicine, prostaglandins are often studied for their role in modulating inflammatory responses and their potential therapeutic applications. These compounds can influence pain perception and are involved in processes such as parturition and the estrous cycle in mares. This page collects peer-reviewed research studies and scholarly articles that explore the synthesis, function, and clinical applications of prostaglandins in equine health.
Eyre P.Systemic anaphylaxis was induced in seven groups of ponies. Systemic hypotension, pulmonary hypotension, and apnea were observed in the control group. Suppression of anaphylaxis was achieved most efficiently with sodium meclofenamate followed by acetylsalicylic acid and diethylcarboamazine. Tripelennamine and methysergide reduced anaphylaxis minimally and burimamide not at all. The findings suggest that histamine and serotonin are of relatively low significance in equine anaphylaxis whereas kinins, prostaglandins and slow reacting substance may be more important.
Nelson AM.Of 275 mares receiving prostaglandin F2alpha-Tham salt for its luteolytic effect upon the corpus luteum, 231 (84 per cent) exhibited signs of oestrus (range 73-95 per cent). Some mares not exhibiting overt oestrus may, nevertheless, ovulate and post-treatment rectal palpation of mares apparently failing to respond is suggested in these cases. Of 210 mares for which subsequent history was available. 104 (49.5 per cent) became pregnant from breeding at the post-treatment oestrus that immediately followed the induced regression of the corpus luteum (range 42.2-55.5 per cent). Fertility is compara...
Douglas RH, Ginther OJ.Prostaglandins F were quantitated by radioimmunoassay in uterine venous plasma of anesthetized mares on day 7 of estrus, days 2, 6, 10, 14 or 18 of diestrus and days 10, 14 or 18 of pregnancy. The PGF concentration was greater (P less than .01) at day 14 of diestrus than at all other days studied. The concentrations at days 10 and 18 of diestrus and at days 10, 14 and 18 of pregnancy were greater (P less than .05) than at day 7 of estrus and days 2 and 6 of diestrus. PGF concentrations at days 10 and 14 were greater (P less than .01) for diestrous than for pregnant mares.
Kooistra LH, Ginther OJ.At day 24 of gestation, pregnant mares were allotted to 1 of 5 treatment groups (3 to 5 mares/group): group A--nontreated controls; group B--intraembryonic injection of 4 mg of colchicine on day 24; group C--removal of embryo on day 24; group D--subcutaneous injection of 1.25 mg of prostaglandin F2alpha (PGF2alpha) on day 32; and group E--removal of embryo on day 24 and subcutaneous injection of PGF2alpha on day 32. In all mares treated with colchicine (group B), the fetal bulge was absent within 2 days. The interval from injection of colchicine to onset of estrus was very short (mean, 4 days)...
Sharma OP.The concentrations of PGF-2alpha in the peripheral blood of five foaling mares were measured by radioimmunoassay. Low levels of PGF-2alpha were detected as early as 1 week before foaling in two of the mares. These levels increased steadily, reaching a peak (1-74 +/- 0-44 ng/ml) during fetal expulsion. A relatively high PGF-2alpha level was found in samples collected 60 min after foaling.
Douglas RH, Garcia MC, Ginther OJ.Luteolysis, determined by corpus luteum weight and progesterone concentration in jugular blood, occurred in uterine-intact and in hysterectomized mares after injection of prostaglandin F2alpha or of an antiserum against an equine pituitary fraction. Results indicated that luteolytic effects of exogenous prostaglandin F2alpha and inhibition of the endogenous luteotrophic activity of the hypophysis (pituitary gland) by antiserum did not involve the uterus.
Arthur GH.The effect of intrauterine saline on reproductive function was studied by infusion of mares in anoestrus, dioestrus, oestrus and prolonged dioestrus. Anoestrous mares were unaffected except near the beginning and end of the breeding season when anovulatory heats were induced. Dioestrous mares infused between Days 5 and 9 returned to heat an average of 3-8 days earlier than expected, and infusions during dioestrus were followed by ovulatory heats of normal fertility. Three mares in prolonged dioestrus showed ovulatory heats within 3 to 9 days of infusion. Infusions during oestrus had no appreci...
Douglas RH, Ginther OJ.Several experiments indicated that prostaglandin F2alpha (PGF2alpha) has luteolytic and abortifacient properties in mares. A single subcutaneous injection of 1-25 mg PGF2alpha on Day 6 of dioestrus was as effective as 10 mg PGF2alpha in inducing luteolysis. Oestrus and ovulation appeared to be synchronized when a single injection of 1-25 mg PGF2alpha was given on Days 7, 10 or 13 after ovulation but not on Days 1 or 4 after ovulation or on Day 2 of oestrus. Intramuscular administration was as effective as subcutaneous administration and 1-25 mg PGF2alpha was the minimal effective systemic dose...
Palmer E, Jousset B.Following an initial observation period of 13 days when plasma progesterone levels were determined, synchronization of oestrus and ovulation was investigated in thirty-three mares treated with a prostaglandin analogue ('Equimate') and HCG. Two courses of treatment were given 8 days apart and each consisted of a single intramuscular injection of Equimate (250 mug) followed 6 days later by an intramuscular injection of HCG (2500 i.u.). The first course was designed to remove all luteal tissue and to induce ovulation of any follicles that developed in response to the withdrawal of progesterone. T...
Alm CC, Sullivan JJ, First NL.Dexamethasone (100 mg/day) injected from Days 318 to 324 of pregnancy induced parturition. Progesterone (500 mg/day) administered daily from Day 318 of pregnancy also shortened gestation while oestrogen (50 mg/day) administered on the same schedule as progesterone had no such effect. Dexamethasone treatment superimposed on the oestrogen or progesterone treatments shortened gestation. Prostaglandin F2alpha alone did not induce parturition, unlike PGF2alpha with dexamethasone, or PGF2alpha given to ovariectomized mares.
Spincemaille J, Coryn M, Vandekerckhove D, Vandeplassche M.Prostaglandin F2alpha (PGF2alpha), administered by untrauterine infusion and intramuscular injection, was used to induce oestrus and ovulation in non-cyclic mares. A satisfactory response rate (80% or more) was obtained and the dose (2-5--7-5 mg) and the time taken for ovulation to occur (up to 9 days) was the same irrespective of the route of administration. Only about one-half of the mares conceived to mating at the induced oestrus but the low conception rate could be attributed to the infertile condition of the mares. Plasma progesterone remained at basal levels after PGF2alpha and oestroge...
Oxender WD, Noden PA, Hafs HD.The luteolytic effect of PGF2alpha, administered by intrauterine infusion or subcutaneous injection during early dioestrus, was observed in mares of mixed breeds. An infusion of 10 mg on Days 7 to 9 after ovulation caused a sharp fall in plasma progesterone levels and induced oestrus and ovulation. Oestrus was significantly longer than in the natural cycle but the time of ovulation in relation to the end of oestrus was normal. The time of return to oestrus following luteolysis was not dependent on the amount of PGF2alpha within the range of doses given. Luteolysis could be induced as early as ...
Kenney RM, Ganjam VK, Cooper WL, Lauderdale JW.Seventy-three Standardbred and Thoroughbred mares in clinical anoestrus during the breeding season were treated with PGF2alpha. The mares were divided into four categories; foaling, barren, maiden and unknown. The response was consistent in all groups. Mares at Days 2 to 4 of dioestrus showed no decrease in plasma progesterone levels, and those at Days 6 to 8 showed a return of progesterone to baseline levels (less than 1 ng/ml) in 24 to 48 hr after treatment. Plasma progesterone levels returned to basal levels in 24 to 48 hr in 93% of mares; progesterone levels had not changed by 96 hr in 7% ...
Oxender WD, Noden PA, Bolenbaugh DL, Hafs HD.To determine the minimal effective dose of prostagiandin (PGF2alpha; tromethamine salt) given subcutaneously (SC), mares of mixed breeding (400 kg av body weight) were given 2-, 3-, 5-, and 10-mg doses from 7 to 9 days after ovulation. In some but not all mares given doses of 2 and 3 mg of PGF2alpha, luteolysis occurred, but doses of 5 or 10 mg of PGF2alpha were luteolytic in all mares. The 10-mg dose of PGF2alpha did not cause luteolysis in mares 1 day after ovulation, and caused luteolysis in only 2 of 5 mares on day 3 after ovulation. The same dose of PGF2alpha, however, caused luteolysis i...
Robinson NE, Dabney JM, Weidner WJ, Jones GA, Scott JB.The digital circulation was isolated in 12 ponies under pentobarbital anesthesia. Blood flow was either controlled by a pump or measured under natural perfusion. The responses to rapid changes and stoppages of blood flow indicated no evidence of autoregulation or reactive hyperemia. Local administration of acetylcholine, histamine, and prostaglandins E1 and E2 decreased prevenous resistance, whereas epinephrine and serotonin caused prevenous constriction. Large doses of epinephrine and serotonin decreased venous caliber. The effects of prostaglandins A1 and F2alpha were variable. The equine di...
Brand A, de Bois CH, Vandenhende R.Parenteral administration of 2.5-5 mg. of prostaglandin F2alpha to horses, 15 mg. to heifers or 25-30 mg to lactating cows and 15 mg. to sheep will induce regression of the corpus luteum (luteolysis) and a fertile oestrus within 48-72 hours. Because of their luteolytic effect prostaglandins may be used in various indications in the field of reproduction. An exception is the pig in which administration of prostaglandins does not induce luteolysis before D12 and therefore fails to induce oestrus. In horses, cattle and sheep, administration of prostaglandins during the first four days of the cycl...
Douglas RH, Ginther OJ.Nine groups of pony mares (3/group) were used in a 3 times 3 factorial experiment. The factors were dose of PGF-2 alpha (0, 0.25 of 1.25 mg and route of administration (im, iu or il). Mares were laparotomized and treated on day 7 postovulation. Jugular blood was collected for progesterone RIA at 0 (pretreatment) and 1,6,12,24,48, and 72 hr posttreatment. In mares given either 0.25 mg or 1.25 mg PGF-2alpha, progesterone concentrations were not significantly different among the three routes at any of the posttreatment times studied except at 6 hr posttreatment. In mares given 0.25 mg, progestero...
Allen WR, Stewart F, Cooper MJ, Crowhurst RC, Simpson DJ, McEnery RJ, Greenwood RE, Rossdale PD, Ricketts SW.This research investigates the use of synthetic prostaglandin analogues, specifically ICI-81008 and ICI-79939, in mares for inducing luteolysis, the regression of the corpus luteum, to manage infertility issues. The study […]
Kasman LH, Hughes JP, Stabenfeldt GH, Starr MD, Lasley BL.Serum and urinary estrone sulfate concentrations were determined in 7 pregnant mares before and after prostaglandin-induced abortion (n = 4) or surgical removal of the fetus (n = 3) to determine the source of estrogen during early pregnancy (gestation days [GD] 44 to 89). Estrone sulfate concentrations also were determined in serum samples (stored frozen for 2 years) from 3 mares that had been ovariectomized between GD 51 and 58. Estrone sulfate concentrations decreased in serum and urine after expulsion or removal of the fetus (urinary patterns were more definitive than were patterns for seru...
Neely DP, Stabenfeldt GH, Kindahl H, Hughes JP, Kendrick JW.The intrauterine infusion of 500 ml of warm sterile saline solution into mares on days 12, 13, or 14 after ovulation failed to alter the ovulatory interval, although intervals were shorter for days 12 and 13 (20.6 days) when compared with those in control mares (21.6 days). The IU fusion shortened luteal-life-span on days 12 (12.0 vs 13.8 days) and 13 (13.0 vs 14.4 days) (P is less than 0.05), but not day 14 (14.0 vs 13.5 days), when comparing the effects of IU infusion with an average of before and after base-line data. There was no effect on the interval from corpus luteum regression to ovul...
Castro T, Jacob JC, Domingues RR, Ginther OJ.Prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) are involved in equine embryo mobility throughout the uterus on Days 11-15 (ovulation = Day 0). On a day (Day 12) of maximal embryo mobility in pregnant mares (n = 13) and before luteolysis in nonbred mares (n = 10), gene expressions were compared between the uterine horns that did and did not contain the mobile embryo and between pregnant and nonbred mares. A cytobrush was used to collect an endometrial sample from the middle of each uterine horn. In nonbred mares, there was no difference for any of the considered gene expressions ...
Takafuji VA, McIlwraith CW, Howard RD.To evaluate the effects of equine recombinant interleukin-1alpha (rEqIL-1alpha) and recombinant interleukin-1beta (rEqIL-1beta) on proteoglycan metabolism and prostaglandin E2 (PGE2) synthesis by equine articular chondrocytes in explant culture. Methods: Near full-thickness articular cartilage explants (approx 50 mg) harvested from stifle joints of a 3-year-old and a 5-year-old horse. Methods: Expression constructs containing cDNA sequences encoding EqIL-1alpha and EqIL-1beta were generated, prokaryotically expressed, and the recombinant protein purified. Near full-thickness articular cartilag...
Watson ED, Zanecosky HG.Immunosuppressive substances which interfere with lymphocyte blastogenesis are released in vitro by embryos and endometrium from mares in early pregnancy. Immunosuppression was not evident when tissues were cultured in the presence of indomethacin (a prostaglandin-synthesis inhibitor). Various prostaglandins (PGs) were added to equine lymphocytes and lymphocyte proliferation was measured after the addition of concanavalin A (Con A) or phytohaemagglutinin A (PHA). PGE2 and PGF2 alpha inhibited Con A-induced blastogenesis down to final concentrations of 1.8 x 10(-9) M and 1.3 x 10(-6) M, respect...
Nagel C, Aurich C.Based on the marked variability in physiological equine gestation length, induction of foaling in mares often results in the birth of dysmature foals. Precise prediction of preparedness of the mare for foaling is thus essential. Treatment with glucocorticoids mimics the fetal signal that initiates birth. Repeated daily dexamethasone treatment in late gestation results in birth of mature foals but the time from initiation of treatment to foaling is highly variable and complications such as dystocia have been reported. Contrary to most expectations, treatment of prepartum mares with progestogens...
Kojima AY, Kobayashi S, Acosta TJ, Kudo M, Miyamoto A, Takagi M, Miyazawa K, Sato K.Microdialysis System (MDS) is a novel technique used for investigation of molecule secretion between different cell populations. Local hormonal secretion at follicular wall has been still unclear. This MDS study was used to determine progesterone (P4), androstenedione (A4), estradiol-17beta (E2) and Prostaglandin F2alpha (PGF2alpha) release in mare pre-ovulatory follicles. Follicles larger than 30 mm were isolated from the ovary and follicular fluid aspirated for hormone assay. Follicular fluid collected from small, middle and large follicles were analyzed by EIA. The concentrations of P4 and ...
Bottoms GD, Johnson MA, Lamar CH, Fessler JF, Turek JJ.Dispersed equine vascular endothelial cells grown in tissue culture, and freshly isolated neutrophils were used to determine direct effects of endotoxin on cyclooxygenase and lipoxygenase products. Endothelial cells (10(7)/ml) or neutrophils (2 X 10(6)/ml) were incubated with (a) buffer, (b) endotoxin (10 micrograms/ml), (c) endotoxin + flunixin meglumine (10 micrograms/ml), or (d) calcium ionophore, A23187 (10 micrograms/ml). Thromboxane (TxB2), prostacyclin (6-keto-PGF1 alpha), and leukotriene C4 (LTC4) were determined in the incubation fluid by radioimmunoassay. Thromboxane and prostacyclin...
Solti L, Eulenberger K, Kurth D, Schöne L.Anoestrous mares were treated with prostaglandin (n = 43) and those that did not respond to prostaglandin (n = 29) with a synthetic progestagen, allyloestrenol, at a dose of 0.05 mg/kg body mass for 12 days. After the cessation of the long-term per os gestagen blockade the animals were checked for heat and, if a preovulatory follicle could be palpated, 2000 IU hCG was administered to induce ovulation. In some animals the plasma 17 beta-oestradiol (E2) and progesterone (P4) levels were also followed up throughout the gestagen treatment and for 10-14 days thereafter. As the favourable oestrus ra...
Morris DD, Henry MM, Moore JN, Fischer K.In laboratory animals, the incorporation of alpha linolenic acid or other n-3 series fatty acids into the diet results in marked changes in cell membrane composition as well as arachidonic acid metabolism. The purpose of the present study was to determine whether endotoxin-induced thromboxane A2 (TxA2) and/or prostacyclin (PGI2) production by equine peritoneal macrophages was altered by feeding horses a diet containing 8% linseed oil as a source of alpha linolenic acid for 8 weeks. Peritoneal macrophages were cultured in vitro in the presence of endotoxin (LPS) (0.5-500 ng/ml) or calcium ionop...
Smits K, Willems S, Van Steendam K, Van De Velde M, De Lange V, Ververs C, Roels K, Govaere J, Van Nieuwerburgh F, Peelman L, Deforce D, Van Soom A.During maternal recognition of pregnancy (MRP), a conceptus-derived signal leads to the persistence of the corpus luteum and the maintenance of gestation. In the horse, the nature of this signal remains to be elucidated. Several studies have focused on the changes in gene expression during MRP, but little information exists at the protein level. The aim of this study was to identify the proteins at the embryo-maternal interface around signalling of MRP in the horse (day 13) by means of mass spectrometry. A distinct influence of pregnancy was established, with 119 proteins differentially expres...
Baxter GM, Tackett RL, Moore JN.Palmar digital arteries and veins removed surgically from healthy horses under general anesthesia were cut into 4 mm vascular rings, suspended in tissue baths, and attached to force displacement transducers for continuous measurement of vascular tension. In vitro vascular responses were determined for acetylcholine, acepromazine, isoxsuprine hydrochloride (isoxsuprine), prostaglandin E2 (PGE2), and prostaglandin I2 (prostacyclin). After preconstriction with norepinephrine hydrochloride (norepinephrine), or prostaglandin F2 alpha (PGF2 alpha), the concentrations needed to produce 50% maximum re...
Vanderwall DK, Betschart RW, Squires EL.The objective of this study was to determine if the primary circulating metabolite of PGF2alpha, 13,14-dihydro-15-keto-PGF2alpha (PGFM), is biologically active and would induce luteolysis in nonpregnant mares. On Day 9 after ovulation, mares (n = 7/group) were randomly assigned to receive: 1) saline control, 2) 10 mg PGF2alpha or 3) 10 mg PGFM in 5 mL 0.9% sterile saline i.m. On Days 0 through 16, blood was collected for progesterone analysis. In addition, blood was collected immediately prior to treatment, hourly for 6 h, and then at 12 and 24 h after treatment for progesterone and PGFM analy...
Taylor TB, Pemstein R, Loy RG.Two trials were conducted to (1) determine the degree of control of ovulation achieved by treating mares in late winter with progesterone and oestradiol-17 beta combined after prior exposure to an artificially increased photoperiod, and (2) to examine the effectiveness of such a procedure incorporated into equine breeding farm management systems. Following a 15-day treatment of 150 mg progesterone and 10 mg oestradiol-17 beta daily with 10 mg PGF-2 alpha on the last day of steroid treatment, 27 of 31 mares ovulated on Days 8-14 after the last injection in one trial. Conception rate for mares m...
Tung JT, Venta PJ, Eberhart SW, Yuzbasiyan-Gurkan V, Alexander L, Caron JP.To determine the effects of recombinant equine interleukin -1beta (reIL-1beta) and 4 anti-inflammatory compounds on the expression and activity of cyclooxygenase (COX)-2 in cultured equine chondrocytes. Methods: Articular cartilage from 9 young adult horses. Methods: Reverse transcriptase-polymerase chain reaction methods were used to amplify a portion of equine COX-2 to prepare a cDNA probe. Northern blot analysis was used to quantify the expression of COX-2 in first-passage cultures of equine articular chondrocytes propagated in media containing dexamethasone (DEX), phenylbutazone (PBZ), pol...
Rigby S, Love C, Carpenter K, Varner D, Blanchard T.Eleven light-breed pregnant mares (335 to 347 d gestaton) were used to evaluate the use of prostaglandin E2 as a cervical ripening agent prior to induction of parturition during the months of April and May. Six hours prior to induction, each mare's cervix was examined per vagina for softness and dilation. Each mare was then assigned to 1 of 2 treatment groups: Group PGE mares (n = 7) received 2.0 to 2.5 mg prostaglandin E2 deposited intracervically; Group SAL mares (n = 4) received 0.5 mL of sterile NaCl deposited intracervically. Six hours later, the mares were readied for parturition by wrap...
Kenney RM, Ganjam VK, Cooper WL, Lauderdale JW.Seventy-three Standardbred and Thoroughbred mares in clinical anoestrus during the breeding season were treated with PGF2alpha. The mares were divided into four categories; foaling, barren, maiden and unknown. The response was consistent in all groups. Mares at Days 2 to 4 of dioestrus showed no decrease in plasma progesterone levels, and those at Days 6 to 8 showed a return of progesterone to baseline levels (less than 1 ng/ml) in 24 to 48 hr after treatment. Plasma progesterone levels returned to basal levels in 24 to 48 hr in 93% of mares; progesterone levels had not changed by 96 hr in 7% ...
Heath MF, Evans RJ, Poole AW, Hayes LJ, McEvoy RJ, Littler RM.The responses of equine blood platelets in citrated platelet-rich plasma to arachidonic acid, U44069 (prostaglandin endoperoxide analogue), adenosine 5'-diphosphate, platelet-activating factor or collagen were investigated by turbidimetric aggregometry. Pre-treatment of the platelets with aspirin (1 mmol/l) or paracetamol (1.3 mmol/l) abolished shape change and aggregation in response to arachidonic acid; decreased the rate of aggregation in response to collagen, with no separate effect on shape change; had no marked effect on aggregation caused by the other agonists; but in no case transforme...
Schwarzbach SV, Melo CF, Xavier PLP, Roballo KC, Cordeiro YG, Ambrósio CE, Fukumasu H, Carregaro AB.Osteoarthritis (OA) is one of the main locomotor disorders in horses. Although nonsteroidal anti-inflammatory drugs are the first-line treatment for OA, opioids could also be used. In previous studies, opioids showed promising anti-inflammatory and analgesic effects. In this study, we aimed to investigate the effects of two opioids (morphine and methadone) against inflammation in lipopolysaccharide (LPS)-stimulated synoviocytes by analyzing microsomal prostaglandin E synthase-1 (mPGES-1) and prostaglandin-endoperoxide synthase 2 (PTGS2) expression. Synoviocytes were obtained from the joints at...
Driancourt MA, Palmer E.An experiment was carried out on pony mares to establish the time of the oestrous cycle at which ovarian follicles are recruited for ovulation. In one group (n=7), the cycle was interrupted at the preovulatory stage by removing the preovulatory follicle; in another group (n=13) the cycle was interrupted at day 6 of the luteal phase by inducing luteolysis with a prostaglandin injection (PG). In a subgroup (n=7) of those given PG, the ovary not bearing the corpus luteum was removed at the time of injection. A further group (n=6) served as surgical controls. The interval to the next ovulation and...
Shand N, Irvine CH, Turner JE, Alexander SL.Jugular blood samples were collected at 4 h intervals from six mares during an oestrous cycle to study the hormonal events that occur around the time of luteolysis. Blood samples from day 10 (day 0 = ovulation) until day 3 of oestrus were assayed for prostaglandin metabolite 13,14-dihydro-15-keto PGF2alpha (PGFM), oxytocin, prolactin, progesterone and oestrogen conjugates. PGF2alpha (0.5 or 1.5 mg) was administered to six mid-dioestrous mares and the oxytocin and prolactin responses were measured. One to five large (peak > or =2 x nadir) pulses of PGFM, oxytocin and prolactin were detected ...
McConnico RS, Argenzio RA, Roberts MC.The objective of this project was to determine early tissue biochemical events associated with increased colonic secretion during the acute stage of castor-oil-induced colitis by measuring cecal mucosal and submucosal malondialdehyde (MDA) and prostaglandin E2 (PGE2), levels in ponies. Intestinal tissue (inflamed or healthy) samples were obtained from 4 age- and sex-matched Shetland ponies. Biochemical methods were used to determine MDA and PGE2 levels in intestinal tissue samples from inflamed and healthy equine intestine. Inflamed tissue MDA and PGE2 levels increased with time after castor o...
Hinrichs K, Riera FL.Ten mares were used to investigate the effect of administration of prostaglandin F2 alpha on uterine tubal motility, as reflected by embryo recovery from the uterus 5 days after ovulation (day 0). Mares were assigned to 3 groups: group A, uterine flush for embryo recovery on day 7; group B, uterine flush for embryo recovery on day 5; and group C, uterine flush for embryo recovery on day 5, after treatment with prostaglandin F2 alpha (10 mg, IM) on day 3. Each mare was assigned to each group once. Embryo recovery rates for the 3 groups were: A, 6 of 10; B, 2 of 8; and C, 0 of 10. The embryo rec...
Loy RG, Buell JR, Stevenson W, Hamm D.Sixty-two non-cycling mares were classified according to the size of largest follicles at the time of treatment with Prostalene, an analogue of prostaglandin (PG) F-2 alpha. Although oestrus occurred in only 77.4% of mares, 98.4% ovulated at an average of 6.8 days after treatment. Greatest variance of interval to ovulation was observed in mares having follicles greater than or equal to 40 mm at the time of treatment. This was due to regression of large follicles about one-third of the time and later ovulation of a succeeding follicle. This resulted also in greatest uncertainty of prediction of...
Vergara-Hernandez FB, Panek CL, Nielsen BD, Robison CI, Colbath AC.To determine the effects of clodronate disodium (CLO) on control and recombinant equine interleukin-1β (IL-1β)-treated equine joint tissues. Methods: In vitro experimental study. Methods: Cartilage explants, chondrocytes, and synoviocytes (n = 3 horses). Methods: Monolayer cultures of chondrocytes and synoviocytes from three horses were subjected to: control media (CON), 5 ng/ml CLO (C/low), 50 ng/ml CLO (C/med), 100 ng/ml CLO (C/high), with and without IL-1β, and 10 ng/ml IL-1β (IL) alone for 72 hours. Cartilage explants from three horses were subjected to CON, IL, C/low, and C/...
Roth TL, White KL, Thompson DL, Horohov DW.It has been proposed that PGE2 is an important immunosuppressant acting at the fetal-maternal interface during pregnancy. We have previously shown that horse conceptus-conditioned medium suppresses lymphocyte proliferation. This experiment was designed to determine if horse conceptus-derived immunosuppressive activity could be attributed to PGE2 production by the trophoblast tissue. Trophoblast tissue from 21-day-old conceptuses was cut into equal sections and cultured in the presence or absence of the prostaglandin inhibitor, indomethacin. Following culture, immunosuppressive activity and the...
Jackman BR, Moore JN, Barton MH, Morris DD.The purpose of this study was to investigate the in vitro effects of flunixin meglumine, a cyclo-oxygenase inhibitor, and ketoprofen, a reported cyclo-oxygenase and lipoxygenase inhibitor, on the synthesis of cyclo-oxygenase end-products thromboxane B2 and prostaglandin E2, lipoxygenase derived 12-hydroxyeicosatetraenoic acid, tumor necrosis factor and tissue factor. Six adult horses were each randomly administered flunixin meglumine (1.1 mg/kg) or ketoprofen (2.2 mg/kg) intravenously every 12 hours with the drug treatments separated by two weeks. Blood samples were obtained prior to initiatin...
Menozzi A, Pozzoli C, Poli E, Dacasto M, Giantin M, Lopparelli RM, Passeri B, Zullian C, Gobbetti T, Bertini S.We investigated the effects of nonselective cyclooxygenase (COX) inhibitors (indomethacin and flunixin meglumine) and selective COX-1 (SC-560) or COX-2 (celecoxib, DUP-398 and NS-697) inhibitors on horse small bowel motility in vitro. At this purpose, samples of equine ileum were put in isolated organ baths for the motility experiments. Nonselective COX inhibitors were devoid of major effects on motility, except for an inhibition of tonic contraction shown by flunixin meglumine. SC-560, selective COX-1 inhibitor, was devoid of significant effects on ileal motility. Selective COX-2 inhibitors r...
Alkhadrawy JMH, Aboelmaaty AM, Abou-Ahmed MM, Ghallab AM.Commercial embryo flushing of horses has required hormonal management of both the donor and recipient mares throughout the breeding season. Unassigned: This study aimed to find out the effect of using human chorionic gonadotropin (hCG) and prostaglandin F2α (PG) on the ovarian and uterine dynamics and hemodynamics, estradiol (E2), progesterone, oxidants-antioxidants, and blood biochemicals in embryo donor mares during the hottest months of the year in a subtropical climate. Unassigned: Three Control estrous cycles of native mares (10-20 years; = 10) followed by two treated cycles with hCG an...
Jacobs RD, Grum D, Trible B, Ayala DI, Karnezos TP, Gordon ME.Probiotics are commonly incorporated into equine diets to impart health and performance benefits; however, peer-reviewed evidence supporting their efficacy in horses is limited. Interestingly, bacteria from the Bacillus genus are gaining interest for their unique ability to impact metabolic, immune, and inflammatory pathways. The objective of this trial was to evaluate a selection of Bacilli for their role in altering the inflammatory response in horses to exercise. Eighteen horses were utilized in a randomized cross-over trial. Horses were randomly assigned to one of 6 starting treatments inc...
