This case report details the clinical presentation of a Mangalarga Marchador stallion exhibiting increased volume in the right scrotum due to fluid accumulation, coupled with an absence of sensitivity upon palpation. A physical examination, ultrasound evaluation, and fluid aspiration for cytological analysis were conducted, initially leading to a diagnosis of hydrocele. However, during surgery, an encapsulated mass surrounded by fibrotic tissue and containing a significant volume of inflammatory fluid (seroma) was identified, with no involvement of the vaginal tunic or testicle. The fluid was fully drained, and the fibrotic tissue was excised, preserving the testicle. Postoperative recovery was satisfactory, and the stallion was discharged without complications. The occurrence of fluid accumulation between the scrotal fascia and dartos tunica, resulting in an encapsulated seroma, is uncommon in equines. This case contributes to discussions on etiology and appropriate nomenclature for this rare condition.

BACKGROUND:Although racehorses represent a dominant segment in equine industry, there are growing concerns regarding injury prevention, with hoof conformation increasingly recognized as a contributing factor. OBJECTIVES:To morphologically and radiographically evaluate the forelimb digits of racehorses at the São Paulo Jockey Club in order to determine the prevalence of dorsopalmar hoof distortions and to compare morphological and radiographic methods for assessing the hoof-pastern axis. METHODS:The forelimb digits of 59 thoroughbred horses aged 3 to 4 years were evaluated using standardized photographic and radiographic imaging techniques. RESULTS:A broken-backward hoof-pastern axis was identified in 100% of cases by all three radiographic methods, compared to only 55.2% by photographic analysis. Radiographic evaluation also detected high prevalences of hoof distortions, including low heel angles (85%), underrun heels (97%), low palmar angles (87%), and negative palmar angles (56%). CONCLUSIONS:The high prevalences of dorsopalmar imbalance-associated hoof distortions in this population are alarming and highlight the need for improved hoof trimming and shoeing practices to prevent injuries, ensure animal welfare, and promote long-term sustainability of this equine activity.

The present study involved seven horses in a randomized crossover clinical trial to evaluate the effect of lidocaine on horses with induced endotoxemia. Horses received intravenous lidocaine (1.5 mg/kg bolus, followed by 0.05 mg/kg bwt/min) or placebo (0.9% sodium chloride at the same manner) one hour before LPS administration (0.03 μg/kg, IV infusion over 30 min). We monitored clinic and hematologic parameters, abdominal auscultation, ultrasound, and pain over time. No relevant clinical differences existed between treatments regarding peristalsis, abdominal pain, or any other parameters before and after endotoxemia induction. These findings do not support the clinical use of lidocaine to mitigate abdominal pain and intestinal hypomotility promoted by endotoxemia in horses.

Postural adaptation is a prominent feature in horses affected by laminitis. Laminitis induces intense pain, especially in the forelimbs, prompting affected horses to assume a caudally displaced trunk posture, resulting in the hyperflexion of the thoracolumbar spine. This study assessed the nature and prevalence of thoracolumbar injuries in horses with chronic laminitis compared to horses without it. Sixty horses were used (thirty laminitic and thirty non-laminitic) of different athletic purposes and ages (2–20 years). The experimental protocol entailed a single assessment of horses’ thoracolumbar spines, utilizing physical examination by MACCTORE, a scoring system developed specifically for this study. Additional evaluations included the Grimace Equine Pain Scale (HGS) and ultrasound exams. Statistical tests were used to compare values (Mann–Whitney or t-test) and lesions prevalences (Fisher) between groups (p < 0.05). The results showed a higher pain manifestation (HGS and heart rate, p < 0.0001) and thoracolumbar-spine-injury levels in chronic laminitis horses, both in MACCTORE clinical examinations (11.7 ± 4.8 vs. 4.2 ± 3.3, p < 0.0001) and general ultrasonographic indices (39.6 ± 12.0 vs. 20.7 ± 7.1, p < 0.0001), including specific examination approaches for various spinal elements. Horses with laminitis presented with a 14-fold higher prevalence of ultrasound-relevant lesions in the thoracolumbar spine (CI: 4.4 to 50.6, p < 0.0001) compared to controls. These findings constitute new evidence of an association between chronic laminitis and the presence of thoracolumbar spine injuries in horses, which may be confirmed by more sophisticated study designs.

The present study involved seven horses in a randomized crossover clinical trial to evaluate the effect of lidocaine on horses with induced endotoxemia. Horses received intravenous lidocaine (1.5 mg/kg bolus, followed by 0.05 mg/kg bwt/min) or placebo (0.9% sodium chloride at the same manner) one hour before LPS administration (0.03 mu g/kg, IV infusion over 30 min). We monitored clinic and hematologic parameters, abdominal auscultation, ultrasound, and pain over time. No relevant clinical differences existed between treatments regarding peristalsis, abdominal pain, or any other parameters before and after endotoxemia induction. These findings do not support the clinical use of lidocaine to mitigate abdominal pain and intestinal hypomotility promoted by endotoxemia in horses.

Although the external conformation of wild horse hooves has been proposed as an ideal model for domesticated modern horses, histological signs of laminitis have been reported among them. With the hypothesis that the lamellar tissue of horses of Iberian origin raised in semi-feral is healthier than those raised in an intensive management system (stall confinement and high-calorie diet intake), the objective was to compare their lamellar tissues. Lamellar tissue samples were taken from the forelimb hoof of eight domesticated Mangalarga Marchador (MM) horses and from six semi-feral Marajoara (MJ) and Puruca (MP) horses. Primary epidermal lamella (PEL) and secondary epidermal lamella (SEL) were measured (length and width) in several regions, and their shapes were morphologically classified into different types. Breed groups were compared using analysis of variance, followed by Tukey or Dunn tests ( P <0.05). Early signs of laminitis such as abnormal keratinization of the abaxial primary dermal lamella, tapered tips of the axial PELs, pointed tips of the SEL, nuclei condensation, and abnormal spatial orientation of the secondary epidermal basal cells (SELBC), were seen only in MM horses. MP horses had a greater interface of epidermis/dermis contact than MJ horses and more rounded nuclei in the round SELBC than MM horses. In agreement with the study hypothesis, semi-feral MJ and MP horses’ lamellae were classified as healthier than MM horses, which showed early signs of endocrinopathic laminitis.

This study aimed to compare the use of enzymatic colorimetry and Friedewald´s formula for the determination of LDL in horses. Were used a total of 260 samples. Direct analysis was also performed to determine LDL, HDL, TG, and TC using the enzymatic colorimetric method. The LDL level was calculated using the Friedewald equation (LDL= TC–HDL–TG/5). The correlations between the direct LDL analysis and the LDL calculated using the Friedewald formula were determined by Pearson’s tests, and the coefficient of determination was also obtained by linear regression using SAS software (P<0.05) and the kappa value. The mean value (± standard deviation) of the LDL-c was 22.12 (±10.34), and that of the result obtained by the Friedewald formula was 19.94 (±19.13). The correlation between the two variants analyzed in this experiment was significant, with a value of P<0.001, presenting a correlation with a value of r=0.688 and R2=0.4893. These results are relevant, given that recent studies have demonstrated a correlation between LDL plasma values and equine metabolic syndrome. Previous studies have reported discrepancies between the data obtained using Friedewald´s method and the LDL-c values directly determined in humans and animals. Determination of LDL using the Friedewald method can be used to estimate the plasma concentration in horses. Nevertheless, the coefficient of determination was not found to be adequate to recommend the Friedewald formula as a replacement for the enzymatic colorimetric method in determining LDL in horses.

With the increase in bacterial resistance in recent decades, there is an increasing need for the association of drugs with antimicrobial effects in treatments. In this context, the objective of this study was to evaluate in vitro the antimicrobial effect of 0.7% procaine hydrochloride associated or not with 0.023% sodium bicarbonate on Escherichia coli, Proteus mirabilis and Staphylococcus aureus, pathogens commonly present in urinary tract infections of dogs, by broth dilution and disc diffusion methods. It is thus concluded that 0.7% procaine hydrochloride solutions; 0.023% sodium bicarbonate and solution containing 0.7% procaine hydrochloride with 0.023% sodium bicarbonate have antimicrobial effect against Staphylococcus aureus and Proteus mirabilis, and only 0.7% procaine hydrochloride has antimicrobial action against Escherichia coli.

Urinary tract infection is a frequent condition in companion animals, where several pathogens may be involved, among them, multidrug-resistant agents to antimicrobials, making their treatment difficult. In this context, adjuvant therapies can be indicated to assist in the treatment. Thus, the objective of this study was to report the antimicrobial action of a solution containing procaine hydrochloride associated with sodium bicarbonate, intravesically administered, in a male feline (domestic cat) with urinary tract infection due to multidrug-resistant microorganism. The cat with a history of urinary infection developed after urethrostomy was attended. The animal was receiving treatment with the antimicrobial amoxicillin with clavulanate, however, without positive clinical and laboratory response. After performing urine culture and antibiogram, where the microorganism Proteus mirabilis resistant to 18 classes of tested antimicrobials was isolated, an intravesical application of 2.0 mL of 0.7% procaine solution plus sodium bicarbonate was performed. After seven days of this application, a new urine culture and antibiogram were performed, which did not show any growth of microorganisms. It is concluded that the 0.7% procaine hydrochloride solution associated with intravesical sodium bicarbonate showed antimicrobial action against multi-resistant Proteus mirabilis, which causes urinary infection in a cat.

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 (P<0.05). There was no statistical difference in the values of the mechanical nociceptive threshold (P>0.05) 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.

EnglishClostridioides (Clostridium) difficile is the main causative agent of antimicrobial-related diarrhea in humans and a major pathogen-associated enteric disorder in foals and adult horses. Moreover, studies have suggested that animals are a possible reservoir of toxigenic C. difficile strains for humans. Despite this known importance, the epidemiology of C. difficile infection (CDI) in equine is still largely unknown. Therefore, this study described six cases of equine CDI occurring in Minas Gerais, Brazil, including the characterization of the isolates. All but one equine included in this research developed CDI after antimicrobial therapy, three of which occurred during hospitalization. Coinfection with Salmonella Heidelberg and S. Infantis was detected in three cases, making the antimicrobial treatment challenging. All animals recovered after metronidazole administration. All C. difficile isolates were susceptible to metronidazole and vancomycin, while three were resistant to moxifloxacin and two were resistant to clindamycin. The isolates were classified as RT126 (n = 4), RT078 (n = 1), and RT014/020 (n = 1), all previously reported infecting humans and animals worldwide portuguesClostridioides (Clostridium) difficile e o principal agente envolvido em diarreias associadas ao uso de antimicrobianos em seres humanos e um enteropatogeno de grande relevância em quadros de diarreia em potros e equinos adultos. Em adicao, estudos tem sugerido que animais sao possiveis reservatorios de estirpes toxigenicas de C. difficile para humanos. Apesar da importância na saude animal e humana, a epidemiologia da infeccao por C. difficile (ICD) e ainda pouco conhecida. Dessa forma, o presente estudo tem como objetivo caracterizar seis casos de diarreia por C. difficile ocorridos em Minas Gerais, Brasil. Com excecao de um animal, todos os equinos incluidos no presente estudo desenvolveram ICD apos antibioticoterapia, tres dos quais durante a hospitalizacao. Coinfeccao por Salmonella Heidelberg e S. Infantis foi detectada em tres casos, tornando o tratamento antimicrobiano desafiador. Todos os animais recuperaram apos administracao de metronidazol. Os isolados obtidos no presente estudo foram sensiveis a metronidazol e vancomicina, porem tres estirpes foram resistentes a moxifloxacina e duas a clindamicina. Os isolados foram classificados como ribotipos 126 (n=4), 078 (n=1) e 014/020 (n=1), todos previamente relatados em seres humanos com ICD no Brasil e em outros paises

A terapia de lesões tendíneas é reconhecida como um desafio na medicina humana e veterinária, em parte devido à dificuldade do completo restabelecimento da morfologia do tendão e de sua resistência biomecânica. O plasma rico em plaquetas (PRP) tem sido utilizado com sucesso na terapia da tendinite, no entanto, ainda há dados divergentes quanto a sua eficácia e não se tem o completo conhecimento de seu mecanismo de ação. Este estudo teve como objetivo avaliar os efeitos do PRP na fase inicial da reparação da lesão induzida no tendão flexor digital superficial (TFDS). Foi realizada tenotomia parcial da face palmar do TFDS com o auxílio de punch dermatológico em 10 ovinos machos e imediatamente instituída a terapia intra-tendínea com 200 µL de PRP autólogo no grupo tratado (GT) e 200 µL de cloreto de sódio 0,9% no grupo controle (GC). Foram realizadas avaliações clínicas, termográficas e ultrassonográficas durante 30 dias após a terapia. Não foram observadas alterações na avaliação clínica entre os diferentes grupos experimentais. Na avaliação termográfica foi observado aumento de temperatura sobre a superfície da lesão tendínea no GC comparado ao GT, após 30 dias da terapia. Na avaliação ultrassonográfica foi evidenciado menor edema no GT comparado ao GC nos momentos 01, 02, 10 e 30 dias após a terapia. Estes achados sugerem modulação do processo inflamatório em resposta a terapia com PRP na fase inicial da reparação tendínea.