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.
Whittle BJ, Moncada S, Vane JR.The activity of prostacyclin (PGI2), PGE1 or PGD2 as inhibitors of platelet aggregation in plasma from human, dog, rabbit, rat, sheep and horse was investigated. Prostacyclin was the most potent inhibitor in all species. PGD2 was a weak inhibitor in dog, rabbit and rat plasma whereas PGE1 and prostacyclin were highly active. Theophylline or dipyridamole potentiated the inhibition of human platelet aggregation by prostacyclin, PGE1 or PGD2. Compound N-0164 abolished the inhibition by PGD2 of human platelet aggregation but did not inhibit the effects of PGE1 or prostacyclin. The results suggest ...
Barnes RJ, Comline RS, Jeffcott LB, Mitchell MD, Rossdale PD, Silver M.The concentrations of 13, 14-dihydro-15-oxo-prostaglandin F(PGFM), the stable metabolite of prostaglandin F, were measured in the plasma of catheterized mares and foetuses and non-catheterized thoroughbred mares and ponies during the last months of gestation. The plasma concentration of PGFM increased gradually towards term in all groups of animals. During the operation for insertion of catheters, maternal and foetal concentrations of PGFM were high, but the values fell to basal levels 24--48 h after the operation. It was found the preoperative starvation (24 h) led to a rise in the concentrat...
Basu R, Chatterjee A.The administration of pregnant mare's serum gonadotropin (PMSG), 30 IU on day 18 of pregnancy, resulted in premature labor in rats. However, this abortifacient efficacy of PMSG was not demonstrable when a simultaneous injection of progesterone, clomiphene, or indomethacin was scheduled, thus suggesting that the action of PMSG is medicated by the estrogen-stimulated release of prostaglandin. The termination of pseudopregnancy in bilaterally hysterectomized rats by PMSG and its reversal by indomethacin revealed that the inhibition of luteal function by PMSG does not require the presence of a ute...
Gupta T, Chatterjee A.Pregnant mare's serum gonadotropin (PMSG) of 10 IU on day 5 of pregnancy induced luteal demise and consequently an absolute resorption of fetuses and placentae resulted on day 16 of pregnancy. Simultaneous regimen of PMSG and indomethacin or cortisone was found to be consistently effective in preventing the luteolytic effect of PMSG. The growth of the fetuses, placentae as well as corpora lutea was found to be parallel to controls. Similarly, shortening of the duration of pseudopregnancy to 10--12 days in the bilaterally hysterectomized rat by PMSG and its retaining the normal duration of 18--...
Jeffcott LB, Rossdale PD.The efficacy and safety of oxytocin, dexamethasone and prostaglandin, used alone or in combination as inducing agents, are discussed. It is contended that insufficient evidence exists to support the routine application of any of these methods in practice. Oxytocin has been the most widely used and it is claimed by some to be free from side effects. However, the synthetic prostaglandin analogue, fluprostenol, seems to pose the least risk to the foetus and dexamethasone appears to be either ineffective, or too dangerous to use at all. The main indications for induced foaling are managerial conve...
Chand N, Eyre P.Nonsteroidal anti-inflammatory drugs inhibit the biosynthesis of kinins and prostaglandins and stabilize leukocyte lysosomal membranes. Nonsteroidal anti-inflammatory drugs also weakly block the biosynthesis of histamine and serotonin, and pharmacologically antagonize kinins, prostaglandins and slow-reacting substance of anaphylaxis. Nonsteroidal anti-inflammatory drugs effectively control both cardiovascular and respiratory manifestations of hypersensitivity in cattle and horses. This, coupled with the contrasting lack of effectiveness of "antiamine" drugs, suggests that bio-amines such as hi...
Allen WE.Seven Welsh pony mares (9 pregnancies) received either 50 mg, 100 mg or 150 mg progesterone on alternate days, starting on day 21 of gestation. All but 2 pregnancies failed following prostaglandin administration on day 27. Although both mares were receiving the 150 mg progesterone dose rate, this treatment was not consistently successful in preventing pregnancy failure after prostaglandin administration.
Kimball FA, Wyngarden LJ.Preliminary studies indicate the presence of PGF2alpha specific binding sites in membrane fractions prepared from equine corpora lutea. The equilibrium binding data indicate an apparent dissociation constant of 3.2 X 10(-9)M and the concentration of binding sites of -0.1 pmoles/mg membrane protein. Competition of several natural prostaglandins for equine luteal PGF2alpha specific binding sites indicates specificity for the 9alpha-hydroxyl moiety and the 5,6-cis doublebond. Significant increases in relative binding affinities were demonstrated for PGF2alpha analogs with a phenyl ring introduced...
Mitchell D, de Gannes R, Sugden EA.THE ABILITY OF PROSTAGLANDIN (PG)F2a and its synthetic analogues to induce luteolysis in the mare has been adequately demonstrated (3, 6). This luteolytic effect has been utilized in the treatment of several forms of cyclic dysfunction encountered in horse breeding. It has been shown that a high proportion of Thoroughbred mares with persistent luteal function (prolonged diestrus) treated with PCF2a analogues will come into estrus within four days of treatment and that they will ovulate normally (4, 10). Thus PG treatment of mares which exhibit aberrant estrous cycles during the breeding season...
Douglas RH, Ginther OJ.In experiment 1, seven groups of pony mares (2 or 3/group) were given either no injections (controls), or 5 (5X) or 10 (10X) daily subcutaneous (SC) injections of 1.25 mg PGF2alpha beginning on days 1, 7 or 13 post-ovulation. Compared to controls (24.5 days), the interovulatory interval was longer (P less than ..05) for day 7, 10X (33.5 days) and day 13, 10X mares (49.0 days) but was not different for the remaining groups. In experiment 2, nine groups of pony mares (4/group) were given either no injections (controls) or 1 (1X) or 10 (10X) daily SC injections of 1.25 mg PGF2alpha beginning on d...
Shepherd GE, Findlay JK, Cooper MJ, Allen WR.A clinical trial involving 359 mares was conducted to ascertain the clinical value of a synthetic prostaglandin analogue (fluprostenol, ICI-81,008) structurally related to PGF2oc for treating mares in prolonged dioestrus. Some 263 mares (73.3%) displayed oestrus within 5 days of a first intramuscular injection of 250 mug fluprostenol and, of those mares later examined for pregnancy, 108 (40%) were found to have conceived during the first induced oestrus. A further 21 mares (8%) cycled normally and conceived to services during the second oestrus. Most (80.3%) of the plasma samples obtained from...
Cooper MJ.Fluprostenol (ICI 81,008) is a 16-aryloxyprostaglandin, structurally related to PGF2alpha. It is a highly potent luteolytic agent, being effective in thoroughbred mares at a single intramuscular dose of 250 mug and having a wide margin of safety in this species. A total of 941 mares have been treated with fluprostenol in an international trial, for various forms of infertility associated with abnormal persistence of luteal function. These mares were selected for treatment on the basis of clinical examination and 760 (approximately 80 per cent) responded fluprostenol by showing oestrus within s...
Douglas RH, Del Campo MR, Ginther OJ.On the day of ovulation (Day 0), 20 pony mares were randomly assigned to one of five groups (4 mares/group) which were given intracarotid arterial (ICA) and intraovarian arterial (IOA) injections on Day 7 as follows: 1) vehicle ICA, vehicle IOA (control); 2) .125 mg PGF2α ICA, vehicle IOA; 3) vehicle ICA, .125 mg PGF2α IOA; 4) .250 mg PGF2α ICA, vehicle IOA; or 5) vehicle ICA, .250 mg PGF2α IOA. Peripheral plasma progesterone and LH concentrations were determined for 0 (pretreatment) and .1, .25, .50, .75, 1, 6, 12, 24, 48, 72 and 96 h posttreatment. The intervals (days) from treatment to ...
Ginther OJ, Domingues RR, Kennedy VC, Dangudubiyyam SV.An inhibitor of PGF2α biosynthesis (flunixin meglumine, FM) was used to study the role of endogenous PGF2α on the luteolytic effect of exogenous PGF2α in mares. A 2-h infusion of PGF2α at a constant rate (total dose, 0.1 mg) on Day 10 (ovulation = Day 0) was used to mimic the maximal concentrations of a spontaneous pulse of a PGF2α metabolite (PGFM). Treatment with FM (1.7 mg/kg) was done 1 h before and 5 h after the start of PGF2α infusion. In hourly blood samples beginning 1 h before the start of PGF2α infusion, progesterone decreased (P < 0.05) similarly by 5 h in each of t...
Pham HC, Lasserre B, Tronche P, Couquelet J, Dossou-Gbete V, Palhares de Miranda AL.The effects of 3-dimethylamino 5-(2',6'-dichlorobenzylidene) 6-methyl (4H)-pyridazine (PC 89) on the biosynthesis of PG I2 and TX A2 using horse aorta and horse platelet microsomes as sources of enzymes and arachidonic acid as substrate, were investigated. PC 89 (1.10(-6) M- 1.10(-3) M) dose-dependently - enhanced the biosynthesis of PG I2: the AD50 was 6.8 X 10(-6) M +/- 1.2 X 10(-9) M, the Vmax did not vary significantly with concentrations: PC 89 increased the affinity of enzyme for substrate - but inhibited TX A2 biosynthesis (ID50 = 3.31 X 10(-3) M +/- 4.8 X 10(-7) M): this inhibiting act...
Ginther OJ, Cuervo-Arango J, Beg MA.The role of passage of follicular fluid into the peritoneal cavity during ovulation in the transient disruption in the periovulatory FSH and LH surges was studied in ovulatory mares (n=7) and in mares with blockage of ovulation by treatment with an inhibitor of prostaglandin synthesis (n=8). Mares were pretreated with hCG when the largest follicle was ≥32 mm (Hour 0). Ultrasonic scanning was done at Hours 24 and 30 and every 2h thereafter until ovulation or ultrasonic signs of anovulation. Blood samples were collected at Hours 24, 30, 32, 34, 36, 38, 48, and 60. Ovulation in the ovulatory gr...
Brooks AC, Menzies-Gow NJ, Wheeler-Jones C, Bailey SR, Cunningham FM, Elliott J.The endothelium plays a major role in the pathogenesis of endotoxemia. Binding of endotoxin (lipopolysaccharide; LPS) to endothelium initiates a range of signalling events, including activation of p38 mitogen activated protein kinases (MAPKs) that are involved in the initiation of inflammatory responses. In the present study we have examined whether clinically relevant concentrations of LPS can activate p38 MAPK in equine endothelial cells and have investigated the role of the kinase in neutrophil adhesion and mediator release. Cultured equine digital vein endothelial cells (EDVEC) were expose...
Emmerich IU.In 2022, one novel pharmaceutical agent was released on the German market for horses or food-producing animals: An injection suspension for horses containing tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells as the active ingredient (RenuTend®) is now available. The authorization of one established veterinary active ingredient was extended to an additional species: The synthetic prostaglandin F2α-analogue cloprostenol (Syncroprost®) received approval for goats. Additionally, for 2 active ingredients (paracetamol, suxibuzone), drugs with a higher content of t...
Bianco AW, Moore GE, Cooper BR, Taylor SD.Flunixin meglumine (FM) is a commonly used Nonsteroidal anti-inflammatory drug (NSAID) in horses, but clinical efficacy is often unsatisfactory. Ketorolac tromethamine (KT) demonstrates superior efficacy compared to other NSAIDs in humans, but its anti-inflammatory effects have not been investigated in the horse. Safety of repeated dosing of KT has not been evaluated. The first objective was to conduct a dose determination study to verify that a previously described dosage of KT would inhibit Lipopolysaccharide (LPS)-induced eicosanoid production in vitro, and to compare KT effects of this inh...
Campbell NB, Blikslager AT.Cyclooxygenase inhibitors are administered to horses to prevent endotoxin-induced elaboration of prostaglandins. However, PGE2 and PGI2 stimulate repair of injured intestine. There are 2 isoforms of cyclooxygenase: COX-1, which constitutively produces prostaglandins and COX-2, which is induced by inflammation. We hypothesised that the nonspecific cyclooxygenase inhibitor flunixin meglumine would retard repair of ischaemic intestinal injury by preventing production of reparative prostaglandins, whereas the selective COX-2 inhibitor, etodolac, would permit repair as a result of continued COX-1 p...
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...
Inoue OJ, Freeman DE, Wallig MA, Clarkson RB.To determine effects of reactive oxygen metabolites (ROMs), with and without flunixin meglumine, on equine right ventral colon (RVC) in vitro. Methods: 18 healthy horses and ponies. Methods: In 3 groups of 6 animals each, short-circuit current and conductance were measured in RVC mucosa in Ussing chambers. The 3 groups received physiologic saline (0.9% NaCl) solution, IV, 10 minutes before euthanasia and tissue incubation in Krebs-Ringer-bicarbonate (KRB) solution; flunixin meglumine (1.1 mg/kg, IV) 10 minutes before euthanasia and tissue incubation in KRB solution; or physiologic saline solut...
Sevinga M, Hesselink JW, Barkema HW.Because the incidence of retained placenta in Friesian mares is estimated to be high, and no reports have been published on the reproductive performance of Friesian mares after retained placenta, we studied postpartum reproductive performance in Friesian brood mares with (n = 54) and without (n = 50) retained placenta. We defined a retained placenta as the failure to expel all fetal membranes within 3 h after the delivery of a foal. We subdivided the group of mares with retained placenta into mares in which the placenta had been removed manually (n = 30) and mares in which it had not (n = 24)....
Booth LC, Oxender WD, Douglas RH, Woodley SL.A gonadotropin-releasing hormone (GnRH) was injected in mares given prostaglandin F2 alpha (PGF2 alpha) to induce luteolysis in an attempt to sunchronize ovulation. Pretreatment with estradiol-17 beta (E2-17 beta) was used to determine whether or not estradiol would enhance the release of luteinizing hormone (LH) after treatment with GnRH. Twelve mares were used in a balanced Latin square crossover design. Mares were injected with PGF2 alpha, treatment A; PGF2 alpha mgnRH, treatment B; or PGF2 alpha me2-17 beta mgnRH, treatment C. The interval +/- SEM from PGF2 alpha injection to estrus was 3....
Donatsch L, Friker B, Sieme H, Kaeser R, Burger D.A potential source of fertility loss in mares is oviductal dysfunction, potentially caused by masses or debris in the lumen, that may prevent either sperm from reaching the fertilization site or the embryo from reaching the uterus. Recently a novel therapeutic method leading to increased pregnancy results was described by infusing misoprostol, a synthetic prostaglandin E, in the uterus of mares with unexplained fertility problems. In this study, we aimed, after examining the compatibility of misoprostol with semen, to evaluate the pregnancy rate after routine preovulatory deep uterine horn app...
Pascoe DR, Pascoe RR, Hughes JP, Stabenfeldt GH, Kindahl H.One hundred mares carrying twin conceptuses between gestation days (GD) 12 and 30 were assigned to 4 groups. Group-1 mares (n = 20) were given a placebo (sterile saline solution, IV, and sesame oil, IM). Group-2 mares (n = 32) were given a single dose of progesterone (625 mg, IM) in sesame oil. Group-3 mares (n = 28) were given multiple progesterone treatments (625 mg, IM) at 6-day intervals until GD 42. Group-4 mares (n = 20) were given a single treatment of flunixin meglumine (500 mg, IV) and progesterone (625 mg, IM). Each group was further assigned to equal subgroups A and B according to t...
van den Boom R, van de Lest CH, Bull S, Brama RA, van Weeren PR, Barneveld A.The importance of osteoarthritis (OA) in the horse and the difficulty in its early diagnosis have led to a search for potential biomarkers of joint disease. If the levels of such markers are to be interpreted accurately, clinicians and researchers need to know whether they are influenced by environmental factors and/or interventions such as exercise and repeated arthrocentesis. Objective: To investigate the influence of repeated arthrocentesis and exercise on nitric oxide (NO), prostaglandin E2 (PGE2) and glycosaminoglycan (GAG) concentrations in synovial fluid (SF) from normal equine joints. ...
Gastal MO, Gastal EL, Torres CA, Ginther OJ.The effects of oxytocin, prostaglandin F2 alpha (PGF2 alpha), and clenbuterol on uterine contractility and tone during anestrus and diestrus, and during mobility and postfixation of the embryonic vesicle were studied in 51 pony mares. Contractility was assessed by scoring real-time ultrasound images, and tone was assessed by transrectal digital compression. Scoring was done by an operator who had no knowledge of treatment assignments. In anovulatory mares primed with progesterone for 16 d, oxytocin did not significantly alter contractility but did stimulate an increase in tone, whereas clenbut...
Colahan PT, Bailey JE, Chou CC, Johnson M, Rice BL, Jones GL, Cheeks JP.Twelve clinically sound, healthy, athletically conditioned Thoroughbred horses were subjected to an incremental exercise stress test to determine the effects and period of detection of a single dose of flunixin meglumine (1.1 mg/kg by intravenous injection) in serum and urine by ELISA. Flunixin concentrations, performance, and hematologic and clinical chemical parameters were measured. All horses were rotated through four treatment groups of a Latin-square design providing for each horse to serve as its own control. Flunixin meglumine reduced prostaglandin F(1alpha) and thromboxane concentrati...
Moreira JJ, Moraes AP, Brossi PM, Machado TS, Michelacci YM, Massoco CO, Baccarin RY.This experimental controlled study was performed to evaluate the composition of autologous processed plasma (APP), and the effects of APP intra-articular injection into healthy equine metacarpophalangeal joints. The effects on joints were analysed with a short-phase protocol and a prolonged-phase protocol using saline-injected joints as controls. For the short protocol, horses received one intra-articular APP injection. Synovial fluid samples were collected prior to the injection and 3, 6, 24, 48, and 16 h after treatment. For the prolonged protocol, the joints received three weekly injections...
Zavy MT, Vernon MW, Asquith RL, Bazer FW, Sharp DC.Two experiments were conducted to assess the effect of exogenous hormone treatment on uterine luminal prostaglandin F (PGF). In the first experiment ovariectomized pony mares received either corn oil (21 days, n = 3), estradiol valerate (21 days, n = 3), progesterone (21 days, n = 3) or estradiol valerate (7 days) followed by progesterone (14 days, n = 4). Progesterone treated mares had higher (P less than .01) uterine luminal PGF compared with all other groups, and no differences were detected between other treatment comparisons. In Experiment II, uterine fluid was collected from 4 ovariectom...
Klein C, Troedsson MH.Maternal recognition of pregnancy in the horse is the sum of events leading to maintenance of pregnancy; in a narrow sense, maternal recognition of pregnancy refers to the physiological process by which the lifespan of the corpus luteum is prolonged. The horse is one of the few domestic species in which the conceptus-derived pregnancy recognition signal has not been identified. The presence of the conceptus reduces pulsatile prostaglandin F(2α) secretion by the endometrium during early gestation in the mare, partly attributed to the reduced expression of cyclooxygenase-2. Cyclooxygenase-2 has...
Burrows GE.Phenylbutazone (PBZ), a classic anti-inflammatory and prostaglandin-synthesis inhibitor drug, was used to determine the role of prostaglandins and other mediators on the development and perpetuation of the response to intraperitoneal Escherichia coli endotoxin administration. The PBZ (15 mg/kg of body weight) was administered IV 30 minutes after endotoxin administration and was repeated later at 6 and 12 hours at a dose of 10 mg/kg. A variety of evaluation measurements (hematologic, blood glucose, pyruvate, lactate and fibrinogen, serum beta-glucuronidase, prothrombin time, blood gases, hepati...
Landoni MF, Foot R, Frean S, Lees P.The objective of this study was to analyse the effects of 4 nonsteroidal anti-inflammatory drugs (NSAIDs) on the production of beta-glucuronidase (beta-glu), tumour necrosis factor alpha (TNF alpha), interleukin-6 (IL-6), interleukin-1 (IL-1) and prostaglandin E2 (PGE2) by lipopolysaccharide (LPS)-stimulated equine synoviocytes. The agents studied were flunixin, tolfenamic acid, S(+)ketoprofen (KTP) and R(-)ketoprofen. LPS-induced release of beta-glu from synoviocytes was inhibited in a concentration dependent manner by all 4 compounds, tolfenamic acid being the most potent. Of the 2 KTP enant...
Owens JG, Kamerling SG, Keowen ML.The eicosanoids are a family of lipid-derived autocoids that are released in response to a variety of physical and hormonal stimuli. In this study, prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) were measured in the digital veins of clinically normal horses and horses with chronic laminitis to determine whether these arachidonic acid metabolites have a role in mediating signs of hoof pain and lesions associated with chronic laminitis. Horses were evaluated at rest and after a brief exercise period, to determine whether eicosanoids are released into the circulation after mild concussion. Dig...
Martínez-Boví R, Cuervo-Arango J.The objectives were to determine: (i) whether intrafollicular administration of PGE2 and PGF2α to mares would hasten follicle collapse and (ii) the differences in reproductive hormone characteristics in mares with spontaneous and prostaglandin-induced follicle collapses. Six mares were followed for two oestrous cycles each: when the mares reached a follicle diameter of 30-35 mm and showed mild-to-moderate endometrial oedema, mares were administered a single 0.5 ml dose containing 500 μg PGE2 and 125 μg PGF2α (treatment cycle) or a placebo (0.5 ml of water for injection; control cycle) into...
Kindahl H, Daels P, Odensvik K, Daunt D, Fredricksson G, Stabenfeldt G, Hughes JP.Three different routes of administering Salmonella typhimurium endotoxin to mimic naturally occurring endotoxaemia were tried in the mare. Bolus injection, repeated bolus injections and continuous low-dose infusion were compared with prostaglandin F2 alpha release, leucocyte count and clinical response. A biphasic prostaglandin release and a pronounced leucopenia of almost identical patterns were seen in all models. Repeated bolus injections showed that the second injection initiated only a small prostaglandin release indicating the development of refractoriness to the treatment. A similar ref...
El-Sheikh Ali H, Scoggin K, Murase H, Norris J, Menarim B, Dini P, Ball B.The equine chorioallantois (CA) undergoes complex physical and biochemical changes during labor. However, the molecular mechanisms controlling these changes are still unclear. Therefore, the current study aimed to characterize the transcriptome of equine CA during spontaneous labor and compare it with that of normal preterm CA. Placental samples were collected postpartum from mares with normal term labor (TL group, n = 4) and from preterm not in labor mares (330 days GA; PTNL group, n = 4). Our study identified 4137 differentially expressed genes (1820 upregulated and 2317 downregulat...
Seanor JW, Byars TD, Boutcher JK.Renal dysfunction secondary to GI disorders may be relatively common in horses. Persistent dehydration of 8-10% of body weight can lead to prerenal azotemia, which may result in renal ischemia and renal disease if uncorrected. Dehydrated azotemic horses with a urine specific gravity less than 1.018 may have renal disease. Urine specific gravity readings greater than 1.025 usually indicate normal kidney function. A urine Na level less than 20 mEq/L and a urine/plasma creatinine ratio greater than or equal to 20:1 indicate prerenal problems. Use of nephrotoxic drugs should be avoided in septicem...
Collins LG, Tyler DE.Phenylbutazone (PBZ) toxicosis was induced in 9 ponies to further define the clinical and pathologic changes occurring with this syndrome. Six additional ponies were treated with PBZ and a synthetic prostaglandin E2 to determine the role of prostaglandins in the pathogenesis of PBZ toxicosis. Ponies given only PBZ exhibited CNS depression, anorexia, weight loss, diarrhea, cyanotic mucous membranes, and oral ulcers. Total serum protein concentration gradually decreased during the 10-day treatment period. Marked mucosal atrophy, focal erosions, and ulcers characterized the lesions in the aliment...
Lees P, Higgins AJ.A model of acute inflammation was used in a cross-over study in Welsh mountain ponies to assess the actions of flunixin meglumine on selected components of a localised inflammatory reaction induced by injecting 0.5 ml of a 2 per cent carrageenin solution into subcutaneously implanted tissue cages. Samples of exudate were harvested at predetermined times between three and 48 hours. Increases in leucocyte numbers and protein concentration were not prevented by flunixin treatment. Prostaglandin E2-like activity was present in exudates from untreated ponies with the highest mean concentration occu...
Macan RC, Camargo CE, Zielinski BL, Cardoso NGH, de Lara NSS, Bergstein-Galan TG, Weiss RR, Kozicki LE.Timed artificial insemination (TAI) has boosted the use of conventional artificial insemination (CAI) by employing hormonal protocols to synchronize oestrus and ovulation. This study aimed to evaluate the efficiency of a hormonal protocol for TAI in mares, based on a combination of progesterone releasing intravaginal device (PRID), prostaglandin (PGF2α ) and human chorionic gonadotropin (hCG); and compare financial costs between CAI and TAI. Twenty-one mares were divided into two groups: CAI group (CAIG; n = 6 mares; 17 oestrous cycles) and TAI group (TAIG; n = 15 mares; 15 oestrous cycle...
Millican AA, Leatherwood JL, Coverdale JA, Arnold CE, Bradbery AN, Larson CK, Lamprecht ED, White SH, Paulk CB, Welsh TH, Wickersham TA.Sixteen weanling Quarter Horses (255 ± 22 kg) were utilized in a 56-d trial to evaluate the effects of trace mineral (TM) source on intra-articular inflammation following a single acute inflammatory insult. Horses were stratified by age, sex, and BW and then randomly assigned to dietary treatment: concentrate formulated with Zn, Mn, Cu, and Co as inorganic sources (CON; n = 8) or complexed TMs (CTM; n = 8). Added TM were formulated at iso-levels across treatments and intakes met or exceeded NRC requirements. Horses were offered 1.75% BW (as-fed) of treatment concentrate and 0.75% BW (as-fed) ...