Topic:Abdominal
Research in the abdominal health and conditions category examines digestive physiology, gastrointestinal disorders, and treatment protocols in horses. This page compiles peer-reviewed studies and journal articles on the pathophysiology of common digestive issues, diagnostic techniques for conditions like colic and gastric ulcers, and evaluations of various treatment strategies.
Evaluation of the effects of intraabdominal hypertension on equine central venous pressure. To evaluate the effect of changes in intraabdominal pressure (IAP) on central venous pressure (CVP) in normal horses. Methods: Experimental, in vivo study. Methods: University Teaching Hospital. Methods: Convenience sample of 7 mixed breed horses-5 geldings and 2 mares. Methods: Pneumoperitoneum was induced in horses under standing sedation with carbon dioxide gas using a laparoscopic insufflator for a total of 60 minutes to simulate clinical elevation in IAP. Pressure was increased stepwise to 20 mm Hg over 30 minutes, and maintained at that pressure for 30 minutes to evaluate the effect of ...
Effects of Equine Chorionic Gonadotropin on Ovulatory and Luteal Characteristics of Mares Submitted to an P4-Based Protocol of Ovulation Induction With hCG. The aim of this study was to evaluate the effect of equine chorionic gonadotropin (eCG) at the end of progesterone (P4) treatment on follicular and luteal characteristics during transition period (TP) and reproductive breeding season (RP). A total of 13 crossbred mares were distributed in two experimental groups in the spring and summer (n = 26). The animals received intravaginal P4 (1.9 g) releasing device from D0 to D10. On removal of P4 device, the mares received 400 IU of eCG (eCG group) or saline solution (control group). Human chorionic gonadotropin (hCG; 1.750 IU) was administered (Dh...
Tensile strength and early healing of self-locking and surgeon’s knots. To compare the biomechanical properties and healing of ventral midline celiotomies (VMC) closed with a self-locking knot combination and forwarder start and Aberdeen end (F-A) vs a traditional knot combination and surgeon's start and end (S-S). Methods: In vivo, experimental. Methods: Twenty-one horses. Methods: Fourteen horses underwent VMC, which was closed with either an F-A (n = 7) or an S-S (n = 7) knot combination. Incisions were subjectively graded by masked evaluators for dehiscence, edema, and drainage. Biomechanical testing was performed on three abdominal segments, and histology was...
Kisspeptin has an independent and direct effect on the pituitary gland in the mare. To more clearly understand the equine gonadotrope response to kisspeptin and gonadotropin releasing hormone (GnRH), peripheral LH and FSH were quantified in diestrous mares after treatment with either equine kisspeptide (eKp-10, 0.5 mg iv), GnRH (25 μg iv), or a combination thereof every 4 h for 3 days. The following observations were made: 1) a diminished LH and FSH response to eKp-10 and GnRH was observed by Day 3, but was not different by treatment, 2) a decrease in basal LH concentration was observed from Day 1 to Day 3 for the eKp-10, but not the GnRH treated mares, 3) there was no ch...
Direct contact may affect the efficacy of stallion exposure in hastening the onset of cyclicity in anestrous mares. Introducing males to seasonally anestrous females has been shown to increase LH concentrations and hasten the first ovulation in ewes and goat does. Investigation of this sociosexual phenomenon in mares has not been well studied. The objective of this study was to determine if direct or indirect exposure of anestrous mares to a stallion would result in a similar increase in LH and hasten the first ovulation. In late February, mares were stratified by parity and age and assigned randomly to three treatments (n = 7/treatment): (1) DXP (direct exposure; mares housed adjacent to stallion and all...
Wound Retractor Laparoscopic Port System for Standing Laparoscopic Cryptorchidectomy in the Horse: A Case Report. Cryptorchidectomy is the most commonly performed laparoscopic procedure in horses. However, its use for the extraction of an abdominal testis has disadvantages such as loss of a resected testis from grasp and fragmentation of the specimen because of the excessive tension required for extraction through a thick body wall. The ring wound retractor laparoscopic port system was recently used in human and small animal surgery to perform laparoscopic-assisted procedures and retrieve large specimens from the abdomen. In the present case, the wound retractor was placed as the ventral port in the right...
Transient suppression of ovulatory ovarian function in pony mares after treatment with slow-release deslorelin implants. Behavior during the estrous cycle of mares can affect their performance and therefore inhibition of cyclical ovarian activity is indicated. We hypothesized that implants containing the GnRH analog deslorelin downregulate GnRH receptors and inhibit ovulation in mares. The estrous cycles of Shetland mares were synchronized with 2 injections of a PGF analog. One day after the second injection (day 0), mares received 9.4 (group D1, n = 6) and 4.7 mg deslorelin (D2, n = 5) as slow-release implants or 1.25 mg short-acting deslorelin as a control (C, n = 5). Ultrasonography of the reproductive trac...
Lethal recreational activities involving horses – A Forensic study. A search was undertaken of the Forensic Science South Australia, Australia, autopsy database over a 25-year period from 1995 to 2019 with the aim of understanding more about the role that recreational horse use not involving racing may have in mortality. Eight cases were found with an age range of 8-73 years (mean 47 years) and a male:female ratio of 5:3. The major category was a fall while riding (N = 7) with the remaining case (N = 1) sustaining a lethal kicking. Blunt craniocerebral trauma was responsible for death in 4 cases with injuries following falls including acute subdural and ...
Luteinizing hormone and ovarian steroids affect in vitro prostaglandin production in the equine myometrium and endometrium. Prostaglandins (PGs) play crucial roles in the regulation of the oestrus cycle and establishment of pregnancy in animals. Luteinizing hormone (LH) and ovarian steroids are involved in regulating endometrial PG production in many species. Their effects on PG production and associated pathways in the mare myometrium and endometrium are the subjects of our interest. This study aimed to evaluate the specific effects of LH and ovarian steroids on equine myometrial and endometrial tissues on (i) PGE and PGF secretion and (ii) transcription of genes encoding specific enzymes responsible for PG synthe...
Ultrasound-Guided Transversus Abdominis Plane Block in Shetland Ponies: A Description of a Three-Point Injection Technique and Evaluation of Potential Analgesic Effects. Colic surgery is one of the most painful procedures carried out in horses. Common strategies to alleviate immediate postsurgical abdominal pain include the administration of potent systemic analgesics; however, these may cause unwanted adverse effects such as cardiovascular depression, ileus, and ataxia. The administration of local anesthetics at the incision site in form of an ultrasound-guided subcostal transversus abdominis plane (TAP) block may therefore be preferred to provide adequate analgesia without significant side effects. To date, no technique for a TAP block in horses undergoing m...
Impact of the corpus luteum on survival of the developing embryo and early pregnancy in mares. It has been more than a hundred years that studies aiming to elucidate the processes involved in cyclicity and pregnancy pointed out the requirement of ovaries and corpora lutea for embryo survival and pregnancy establishment. For horses, luteal progesterone is essential for pregnancy only during the first trimester. This progestational support is complex among domestic animals as ovarian luteal function is further enhanced by the LH-action role of equine chorionic gonadotropin (eCG) starting ∼ on Day 35 of pregnancy. Increased eCG secretion leads to the formation of supplementary corpora ...
Correlation Between Peritonitis and Incisional Infections in Horses. Surgical site infection of abdominal incisions is an important complication after laparotomy with increased risk of incisional hernia formation in horses. This study aims to evaluate the healing process of abdominal incisions and correlate peritonitis with the occurrence of surgical site infection and incisional hernias. Nine horses underwent standardized laparotomy, intestinal exploration, and induced septic peritonitis. Standardized relaparotomy was performed two (n = 3), four (n = 3), and six (n = 3) months later to evaluate the abdominal cavity for adhesions and to collect the sutured v...
Superovulation, embryo recovery, and pregnancy rates from seasonally anovulatory donor mares treated with recombinant equine FSH (reFSH). The effectiveness of different treatments with recombinant equine FSH to stimulate follicular growth, multiple ovulations and embryo production in seasonally anovulatory mares was evaluated. During mid-winter season (July-August in Argentina, South America) forty light breed donor mares, presenting follicles <10 mm in diameter and no CL at ultrasound examination (deep-anestrus), were randomly assigned (n = 10/group) to one of the following treatments: Group 1: twice daily intramuscular (IM) injections of 0.65 mg reFSH (AspenBio Pharma, CO), Group 2: once daily IM injection of 1.3 mg ...
Intrabladder pressure as predictor of intra-abdominal pressure in horses. To investigate effects of postural changes and bladder distention on intrabladder pressure whilst estimating intra-abdominal pressure in horses. Two-year cohort study. Patients admitted for elective surgical procedures unrelated to gastrointestinal or genitourinary tract. School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil. 20 adult horses, 11 males (stallions and geldings) and 9 females; between 3.5 and 12 years, weighing 350 to 500 kg. Intra-abdominal pressure was directly-recorded through abdominocentesis at the ventral midline with a fluid-filled system. Intrabladder ...
Transition to the ovulatory season in mares: An investigation of antral follicle receptor gene expression in vivo. The inability to obtain in vivo samples of antral follicle wall layers without removing the ovaries or sacrificing the animals has limited more in-depth studies on folliculogenesis. In this study, a novel ultrasound-guided follicle wall biopsy (FWB) technique was used to obtain in vivo follicle wall layers and follicular fluid samples of growing antral follicles. The expression of proliferative, hormonal, angiogenic, and pro-/antiapoptotic receptors and proteins in the follicular wall among three follicle classes were compared during the spring transitional anovulatory (SAN) and spring ovulato...
Ultrasonographic visualisation of the mesenteric vasculature in horses with large colon colic. Ultrasonographic visualisation of the mesenteric vasculature of the large colon (LC) from the right side of the abdomen in cases of displacement and volvulus has been described. However, the LC can move freely within the abdomen and its mesentery can potentially contact both sides of the abdominal wall. Methods: Thirty-four horses presented with LC-related colic that had visible LC mesenteric vasculature visible on abdominal ultrasound were included. A control group was made including horses with confirmed small intestinal-related colic. The objective of this study was to evaluate the visibili...
[Sonographic topography of abdominal organs and structures in equine neonates]. The study aimed to present a systematic and standardized examination for neonatal foals' abdominal sonography and to describe physiological topographic conditions of some abdominal organs and structures. Methods: A standardized sonographic examination of the abdomen was performed in 57 foals in left and right lateral recumbency. Left and right intercostal spaces as well as the ventral abdomen which was divided into 6 segments (left, middle and right cranial, left middle and right caudal abdomen) were examined. The locations, in which the various organs could be found, were described. Furthermo...
Deslorelin and naltrexone stimulate follicular development in mares during autumn transition and early anestrus. Horses are long-day breeders and commence ovarian follicular activity during the spring. Evidence suggests that there is an endogenous circannual rhythm in mares, and it is uncertain whether hormonal manipulation during or immediately following the fall transition induces follicular development. The current study was designed to test the hypothesis that both deslorelin and naltrexone induce follicular development in late fall transitioning or anestrous mares. Five of six mares treated with deslorelin, and 4 of 6 mares treated with naltrexone, developed a pre-ovulatory-sized follicle and were i...
Effects of follicular ablation and induced luteolysis on LH and follicular fluid factors during the periovulatory period in mares. Haemorrhagic anovulatory follicles (HAFs) are the most common pathological anovulatory condition in the mare. To enhance understanding of the physiopathology of HAFs, the aim of the present study was to determine the effects of an induced-follicular wave on LH concentrations and follicular fluid factors relevant to the ovulatory process. Mares were allocated to treatment or control groups (n = 7/group) in a crossed over design during 14 oestrous cycles with a period of one cycle occurring when there were no treatments between the times when treatments were administered. In the treatment gr...
Deficiency in proliferative, angiogenic, and LH receptors in the follicle wall: implications of season toward the anovulatory condition. This study aimed to gain insight on the effect of different seasons of the year on the expression pattern of growth factor and hormone receptors involved in follicle development. A novel follicle wall biopsy technique was used to collect in vivo follicle wall layers (ie, granulosa, theca interna, and theca externa) and follicular fluid samples from growing dominant follicles, simultaneously and repeatedly, using the same mares during the spring anovulatory (SAN), spring ovulatory (SOV), summer (SU), and fall ovulatory (FOV) seasons. The immunofluorescent expression patterns of epidermal growt...
Accelerated Idioventricular Rhythm Associated With Isoflurane Administration in a Foal: A Case Report. A 2-day-old filly was referred to the hospital with abdominal pain and constipation. The foal presented tachycardia, tachypnea, hypoxemia, hyperlactatemia, and abdominal distension. Meconium impaction was diagnosed, and the filly underwent abdominal surgery. Diazepam and butorphanol were administered for anesthesia premedication, but sedative effects were mild. Xylazine was used to enhance sedation and ketamine was subsequently administered for induction. The foal showed swallow reflex and head movement when intubation was attempted. Consequently, isoflurane on oxygen was provided via an anest...
Pressure algometry for assessment of abdominal wall sensitivity in horses after ventral midline coeliotomy. To assess the clinical course of abdominal wall sensitivity after ventral midline coeliotomy in horses by determining mechanical nociceptive thresholds (MNTs) during hospitalization, and to determine the inter-observer reliability of pressure algometry on the abdominal wall. Methods: Observational, cohort study. Methods: A total of 13 horses presenting with signs of abdominal pain/colic undergoing ventral midline coeliotomy and 10 healthy horses without an abdominal incision. Methods: Measurements were performed on days 1, 3, 5, 7 and 9 postoperatively using a pressure algometer. Measurement s...
Idiopathic peritonitis in horses: a retrospective study of 130 cases in Sweden (2002-2017). Peritonitis in horses is historically associated with prolonged treatment regimens of broad-spectrum antimicrobials and a guarded prognosis for survival. The condition is most often seen as a secondary complication to traumatic injuries involving the abdominal cavity, rupture of bowel or abdominal surgery. However, cases of idiopathic peritonitis with no such underlying cause have been described. In Sweden idiopathic peritonitis is commonly identified and, in contrast to peritonitis secondary to traumatic incidents, affected horses appear to respond well to medical treatment. The objectives of...
Enhancing Fertility in Mares: Recombinant Equine Gonadotropins. Advanced reproductive technologies have been developed to enhance fertility in mares and stallions. Some of these technologies in mares include superovulation, embryo transfer (ET), intracytoplasmic sperm injection (ICSI), oocyte transfer (OT), gamete intrafallopian transfer (GIFT), and cloning. Superovulation can provide multiple oocytes for these techniques. This review will focus on how recombinant equine follicle-stimulating hormone (reFSH) and recombinant equine luteinizing hormone (reLH) are important for superovulation and ET and may be useful for ICSI, OT, GIFT, and cloning. Superovula...
Cellular and molecular mechanisms of the preovulatory follicle differenciation and ovulation: What do we know in the mare relative to other species. Terminal follicular differentiation and ovulation are essential steps of reproduction. They are induced by the increase in circulating LH, and lead to the expulsion from the ovary of oocytes ready to be fertilized. This review summarizes our current understanding of cellular and molecular pathways that control ovulation using a broad mammalian literature, with a specific focus to the mare, which is unique in some aspects of ovarian function in some cases. Essential steps and key factors are approached. The first part of this review concerns LH, receptors and signaling, addressing the descripti...
Luteinizing hormone concentrations in healthy horses and horses with trigeminal-mediated headshaking over an 8-hour period. Trigeminal-mediated headshaking results from a low threshold for firing of the trigeminal nerve. A seasonal component has been implicated in onset of clinical signs, which occur during the spring and summer months. Geldings are overrepresented in the affected population and hormonal differences as compared to a healthy control population of geldings might contribute to headshaking. Objective: To assess concentrations of luteinizing hormone (LH) over an 8-hour period in gelded healthy controls and horses affected with headshaking. Our hypothesis was that geldings with seasonal headshaking would...
Salivary alpha-amylase activity and concentration in horses with acute abdominal disease: Association with outcome. Salivary biomarkers could be useful to objectively evaluate critical illness and prognosis for survival in horses with acute abdominal disease. Objective: To compare salivary alpha-amylase (sAA) activity and concentration in healthy horses and horses with acute abdominal disease, and evaluate the association between sAA activity and concentration with disease severity and outcome. Methods: A prospective cohort. Methods: sAA activity, measured using a colorimetric commercial kit, and concentration, measured using a Time-resolved immunofluorometric assay, in 25 healthy horses and in 33 horses wi...
Differential Regulation of Gonadotropins in Response to Continuous Infusion of Native Gonadotropin-Releasing Hormone in the Winter Anovulatory Mare and Effects of Treatment With Estradiol-17β. We tested the hypotheses that in winter anovulatory mares (1) both chronic daily injections of estradiol-17β (E2) and subcutaneous E2 implants could enhance pituitary secretion of gonadotropins in response to continuous subcutaneous infusion of native gonadotropin-releasing hormone (GnRH); and (2) the secretory pattern of follicle-stimulating hormone (FSH) in response to continuous subcutaneous infusion of native GnRH is similar to that of luteinizing hormone (LH) but differs between mares that develop or fail to develop an estrogen-active, preovulatory follicle. In Experiment 1, 20 winter an...
Total intravenous anesthesia with alfaxalone, dexmedetomidine and remifentanil in healthy foals undergoing abdominal surgery. To evaluate effects of anesthesia induced with alfaxalone and maintained with alfaxalone, dexmedetomidine and remifentanil infusions in foals. Methods: Prospective, experimental study. Methods: A group of six healthy foals [median (range) 11 (8-33) days] undergoing abdominal surgery. Methods: Intravenous (IV) dexmedetomidine (3-7μgkg) provided sedation for insertion of a pulmonary artery catheter. IV anesthesia was induced with alfaxalone (2mgkg) and maintained with alfaxalone (6mgkghour), dexmedetomidine (1μgkghour) and remifentanil (3μgkghour). Foals were endotracheally intubated and lung...
Bursting strength of surgeon’s and self-locking knots for closure of ventral midline celiotomy in horses. To compare the bursting strength and failure mode of ventral midline celiotomy closed with a simple continuous suture pattern with 1 of 2 knot combinations, a novel self-locking knot combination of a forwarder start with an Aberdeen end knot (F-A) and a traditional combination of a surgeon's start with a surgeon's end knot (S-S). Methods: Ex vivo experimental. Methods: Equine cadavers (n = 14). Methods: A 20-cm ventral midline celiotomy was created in 14 equine cadavers. Horses were assigned to celiotomy closure with an F-A or S-S knot combination. Prior to closure, a 200-L inflatable blad...