Morphine has significant clinical and analgesic effects in horses, but its impact on the gastrointestinal tract requires further understanding. This study assessed the analgesic and gastrointestinal effects of morphine in horses undergoing elective orchiectomy in the quadrupedal position. Thirty uncastrated male horses were randomly assigned to three groups: orchiectomy without morphine and sedation protocol (OSM), orchiectomy with morphine and sedation protocol (OM), and administration of morphine alone in the absence of orchiectomy (M). The anesthetic protocol involved acepromazine (0.05 mg/kg IV) and detomidine (10 mcg/kg IV) sedation in groups OSM and OM, with morphine sulfate (0.05 mg/kg IV) given to OM and M, and NaCl to OSM. The team measured clinical parameters, pain, and sedation using the EQUUS-FAP scale, while they monitored bowel motility and gastric dilation through abdominal ultrasound. These assessments were performed on the previous day (m1), 20 min before surgery (m2), and at various time points following the administration of morphine or saline solution: one hour (m3), two hours (m4), four hours (m5), six hours (m6), and eight hours (m7) post-procedure for all three groups. There was no significant difference in pain score between OSM and OM, though OM had better sedation. Ultrasound revealed decreased colon contractions and minor gastric dilation in OSM and OM, normalizing within 6 h. Group M showed reduced motility and significant gastric dilation lasting 8 h. In conclusion, while morphine enhanced sedation without causing greater gastrointestinal dysfunction than OSM, its administration alone resulted in a more pronounced reduction in gastrointestinal motility and an increased risk of gastric dilation.

The intussusception of the large intestine in adult horses has been poorly reported. The aim of this study is to report a case of an acute abdomen due to cecocolic intussusception in a Brazilian Sport Horse mare, aged eight, after the administration of imidocarb dipropionate. The drug used for the treatment of piroplasmosis caused a state of dysmotility in the large intestine and subsequent abdominal discomfort. Surgical intervention was necessary, performed through a median celiotomy, opting for partial typhlectomy due to tissue and circulatory compromise. The postoperative evolution was satisfactory and without serious complications, with a good short- and long-term prognosis, as the patient continued to perform its athletic functions.

A multimodal approach is recommended to optimize perioperative pain control in animals, although opioid use in horses remains limited due to the risks of central nervous system (CNS) stimulation and reduced intestinal motility. A group of 19 healthy, male, mixed-breed horses were divided into two groups and medicated with acepromazine (0.05 mg kg⁻¹) and detomidine (10 µg kg⁻¹), with methadone (0.05 mg kg⁻¹) (ADM) or saline (ADS) administered intravenously (IV). Physiological variables, intestinal motility, gastric distention, and facial pain (EQUUS-FAP) were evaluated one day before (DB), before the surgical procedure (BS), and at 1, 2, 4, 6, and 8 h (T1h–T8h) after administration (ADM-ADS). Results are presented as means with standard deviation or medians with an interquartile range. Analysis of variance, the Mann–Whitney, and Durbin tests were applied (p < 0.05). Intestinal motility was reduced at T1h and T2h, returning to baseline by T6h and T8h in both groups. Ultrasonographic examination revealed reduced motility, with less significant changes in the left ventral colon (LVC), right ventral colon (RVC), and cecum. Gastric dilatation was more pronounced in the ADM group at T1, 4, 6, and 8h. EQUUS-FAP scores were significantly lower in ADM at T2, 4, and 6h. ADM protocol may aid chemical restraint and analgesia without increasing hypomotility.

The analgesic specificity of navicular bursa (NB) anesthetic infiltration is still questionable. The study aimed to determine the mechanical nociceptive threshold of non-specific analgesia in the dorsal lamellar stratum, as well as in the sole, coronary band, and heel bulbs of the hoof, after navicular bursa anesthetic infiltration. Six healthy horses with no clinical or radiographic changes of the digits and no communication between the NB and the distal interphalangeal joint, were used. After random selection, the NB of one of the forelimbs was infiltrated with 2% lidocaine and the contralateral one with lactated ringer’s solution. Contrast was added to confirm radiographic infiltration. The mechanical nociceptive threshold was determined using a portable pressure dynamometer, before and at various times after the infiltration, in 10 points of the hoof. The effects of time and treatment were verified by ANOVA (P0.05) in all regions evaluated. However, in one of the six hooves that receives lidocaine, complete absence of response to the painful stimulus (maximum force of 6 Kg over an area of 38.46 mm², for a maximum of 4 seconds) was observed in the dorsal lamellae between 30 and 60 min after infiltration. In conclusion, lidocaine infiltration of NB did not promote significant increases in the nociceptive threshold of the sole, coronary band, bulbs of the heel and dorsal lamellae clinically healthy horses. However, the occurrence of analgesia in one of the six hooves subjected to NB anesthesia indicates that the technique may not be fully specific in few horses.

Cutaneous pythiosis is an important disease affecting horses raised in regions with a hot climate and water stagnation, occurring throughout all regions of Brazil. The disease progresses rapidly, and treatment for chronic lesions is challenging. The purpose of this study was to evaluate the efficacy of fluconazole after surgical excision and electrocauterization of cutaneous lesions in horses naturally infected with Pythium insidiosum. We treated 10 horses with cutaneous pythiosis, whose diagnoses were confirmed by histopathological and immunohistochemical examinations. After surgical debridement of lesion, animals received fluconazole orally for 21 days, in combination with topical treatment for the wounds. After 7 days of therapy, there was decreased serosanguineous secretion and no kunkers in the wounds in all horses. All lesions healed completely after therapy, and there were no recurrences 10 months after discharge. When associated with surgical excision, oral fluconazole therapy was an effective treatment in clinical cases of equine cutaneous pythiosis.

Anais do Simpósio Internacional do Cavalo Atleta (SIMCAV) (978-65-5941-211-2) - Histologia Lamelar Do Casco De Equinos Das Raças Marajoara E Puruca Criados Em Estado Semisselvagem