Veterinary Research Forum

Abstract Aquaculture has a fundamental role in supporting global food security. In response to the escalating human requirement for protein, the production of aquatic species is expanding rapidly. Conversely, aquatic animals are frequently subjected to a variety of husbandry stress, including handling and high stocking densities. They trigger physiological stress responses negatively affecting biological processes, such as somatic growth, reproduction, and immune function, ultimately resulting in inferior performance and high mortality rates. Although antibiotics are still extensively employed, their persistent administration is associated with the emergence of bacterial resistance, destabilizes endogenous microbiota, and causes chemical residues accumulation within aquatic environments. Therefore, the industry has shifted towards eco-friendly therapeutic strategies. In this context, plant essential oils have emerged as promising feed additives. The EOs contain a rich array of bioactive compounds, possessing anti-bacterial, anti-oxidant, and immuno-stimulatory activities. The administration of EOs has been evaluated in a wide range of aquatic species to characterize their therapeutic potential and establish optimal inclusion levels. Research findings indicate that plant EOs represent effective substitutes for antibiotics, playing prominent roles in growth promotion, oxidative stress mitigation, and immune modulation. The present context reviews the beneficial roles of essential oils in modern aquaculture.

Abstract Although equine chorionic gonadotropin (eCG) combined with gonadotropin-releasing hormone (GnRH) is known to improve reproductive rates by increasing the numbers of ovulating oocytes, the actions of these hormones on embryo implantation have not been elucidated. We herein eliminated the effects of embryos by performing embryo transfer and elucidated the effects on embryo implantation after hormonal treatment. The recipient mice were allocated to four groups, including control, eCG, GnRH, and eCG + GnRH groups. Well-developed blastocysts were transferred into recipients, and implantation sites were counted five days after embryo transfer. Our results revealed that embryo implantation rates in the eCG and eCG + GnRH groups were significantly lower than GnRH and control groups; eCG and eCG + GnRH groups didn’t differ, and the implantation rate was the lowest in the eCG + GnRH group. When we evaluated estrogen and progesterone concentrations in four groups on embryonic day 0.5 to embryonic day 3.5, we noted that serum estrogen levels in eCG + GnRH group were significantly higher than the other groups, while progesterone levels were significantly lower than the control group, and that the progesterone/estrogen ratio was significantly reduced relative to the control group. Finally, the expression of the endometrial receptivity-related Lif gene was significantly diminished in the eCG + GnRH and eCG groups compared to the other groups. These results suggest that eCG combined with GnRH as a super-ovulatory regimen reduced mouse embryo implantation rates via an estrogen-mediated impairment of endometrial receptivity.

Abstract This study aimed to determine whether the sperm acrosome-associated 1 (SPACA1) gene exhibits differential expression between X- and Y-bearing spermatozoa of Bali bulls and assess its potential as an RNA biomarker for sperm sexing. Sexed frozen semen (X or Y fractions) from Bali bulls was obtained from the Singosari National Artificial Insemination Center, Malang, Indonesia. Post-thaw semen quality was evaluated for motility, viability, abnormality, concentration, and plasma membrane integrity. Total RNA was extracted separately from X and Y fractions using easy-BLUE reagent, and SPACA1 expression was quantified by RT-qPCR using GAPDH as an internal control. Relative expression was calculated by the 2^−ΔΔCt method, and group differences were analyzed with the Mann-Whitney U test. The SPACA1 expression was numerically higher in X-bearing than Y-bearing spermatozoa (1.00 versus 0.51), but the difference was not significant. Thus, SPACA1 transcripts do not provide a reliable molecular marker for sperm sex differentiation. Future work should focus on protein-level characterization of SPACA1 and exploration of sex-biased surface proteins for immunological sexing. This research supports Sustainable Development Goal 2: Zero Hunger, by contributing to reproductive efficiency in livestock, and Sustainable Development Goal 12: Responsible Consumption and Production, through development of cost-effective, sustainable sperm sexing technologies.

Abstract Cholestasis, a multi-faceted liver complication arising from an imbalance in bile production and secretion, can lead to damage in extra-hepatic organs, including the reproductive system. This study aimed to investigate the therapeutic potential of Livergol^®, a silymarin-based drug, in the reproductive complications induced by experimental cholestasis in mature male rats. Twenty adults male Wistar rats were randomly divided into four groups (n = 5), including group 1 (control) remained untreated, group 2 (sham) underwent laparotomy and bile duct manipulation without ligation, group 3 (cholestasis) underwent bile duct ligation (BDL) to induce experimental cholestasis, and group 4 (cholestasis + Livergol^®) received oral Livergol^® (300 mg kg^-1) for 4 weeks post-BDL. After the study period, testicular histopathology was evaluated using Johnsen's score and the Cosentino criterion. Epididymal sperm parameters, including count, viability, and motility, were also assessed. The BDL-induced cholestasis caused significant testicular damage, evidenced by a decreased Johnsen's score and an increased Cosentino criterion. It also led to a significant reduction in sperm count, viability, and motility. Treatment with Livergol^® significantly ameliorated these effects, leading to a higher Johnsen's score, a lower Cosentino criterion, and marked improvements in all evaluated sperm parameters compared to the untreated cholestatic group. Oral administration of Livergol^® effectively attenuates testicular damage and improves spermatogenesis and sperm quality in rats with experimental cholestasis. These findings suggest Livergol^® as a promising protective agent against cholestasis-induced reproductive toxicity, likely due to the anti-oxidant properties of its active component, silymarin.

Abstract Disorders and injuries of the fetlock joint, encompassing both bone and soft tissue, are significant causes of limb pain and lameness in horses. Over time, these conditions can lead to joint dysfunction and a diminished quality of life. This study aimed to identify fetlock joint disorders using radiological examinations conducted during pre-purchase evaluations of horses and to evaluate the influence of age and sex on their incidence rates. 100 horses were selected from equestrian centers in Tehran Province during 2017 - 2020. As part of pre-purchase examinations, standard radiographic projections of the fetlock joints of all four limbs were obtained. Among the 100 horses examined, 28 showed no abnormalities in the fetlock joint, while 72 exhibited at least one disorder. Osteoarthritis was the most frequently observed condition, with an incidence of 26.75%, followed by soft tissue swelling (15.80%), medial and lateral proximal sesamoiditis (6.00%), osteochondritis dissecans (7.50%) and avulsion fractures (1.50%). Other disorders accounted for less than 5.00% of cases. The prevalence of disorders was significantly higher in the forelimbs compared to the hindlimbs, while no significant difference was found between male and female horses. The findings of this study underscored the importance of conducting pre-purchase radiographic examinations, particularly of the fetlock joints in both forelimbs and hindlimbs. These evaluations are crucial for identifying potential bone complications and for assessing the prognosis of a horse athletic performance.

Abstract The Accessory Gene Regulator (agr) operon as part of the quorum-sensing system, is responsible for regulating numerous virulence factors in Staphylococci. Furthermore, the ability of the opportunistic pathogen Staphylococcus pseudintermedius to form biofilm is a significant contributor to chronic diseases. Our aim was to evaluate of the association between different agr groups and the expression of the icaD gene related to biofilm formation among S. pseudintermedius isolates from nasal samples. Fifty nasal swabs were collected from broiler chickens and phenotypic and molecular tests were performed to isolate S. pseudintermedius from the samples and investigate their agr genotype. The biofilm production capacity of the isolates was determined using both a microtiter plate assay and amplification of the icaD gene. The S. pseudintermedius was detected in the 86.84% of samples. The assessment of agr typing results revealed that most of the strains (69.70%) were classified in agr group I. The relative frequency of biofilm producing S. pseudintermedius isolates was 75.76% and all of them harbored the icaD gene. The expression level of the icaD determinant was significantly higher among isolates in agr group I than other agr groups. These results suggest that broiler chickens may act as a reservoir for the transmission of S. pseudintermedius to humans which should be considered a potential zoonotic bacterium capable of producing different virulence factors like biofilms.

Abstract Testicular ischemia-reperfusion injury during testicular torsion is strongly influenced by oxidative stress caused by excessive accumulation of uncaptured reactive oxygen species. Kisspeptin-10 (Kiss-10), a biologically active fragment of kisspeptin peptide family, has demonstrated significant anti-oxidant and anti-apoptotic properties. Recent studies indicate that Kiss-10 can mitigate oxidative stress by reducing reactive oxygen species levels and enhancing the activity of endogenous anti-oxidant enzymes, such as superoxide dismutase and catalase. This study examined the effects of Kiss-10on ischemia-reperfusion injury in testicular torsion/detorsion (T/D) of male rats. Twenty male rats were divided into four groups, including the control group and three treatment groups (720° T/D, 720° T/D + 0.50 µg kg^-1 Kiss-10, and 720° T/D + 1.00 µg kg^-1 Kiss-10). After inducing 720° clockwise testicular torsion for 2 hr, sperm parameters, such as number, motility, viability, DNA damage, and hypo-osmotic test were evaluated. The results showed that 720° T/D can increase sperm DNA damage. Also, it also had negative effects on overall motility and other properties, such as viability and plasma membrane functionality. The results also showed that administration of Kiss-10to T/D rats can reduce DNA damage. It could also increase overall motility, viability, and plasma membrane functionality compared to the T/D group. Based on our results, Kiss-10 provides significant protection against acute T/D injury to the testis when administered after spermatic cord torsion in rat.

Abstract Salbutamol is a primary bronchodilator for feline asthma management. However, comprehensive data on its cardiovascular safety in cats are limited despite its widespread clinical use. This study aimed to characterize the acute cardiovascular and respiratory responses following nebulized salbutamol administration in healthy feline subjects, with an emphasis on clinical safety assessment. Twenty healthy adult cats received nebulized salbutamol (3.75 mg per 20 min). A comprehensive cardiovascular evaluation, including vital signs monitoring, electrocardiography, and echocardiography, was performed before and 15 min after treatment. Salbutamol administration was associated with minimal physiological alterations. Heart rate increased from a mean of 204.10 ± 33.09 to 218.35 ± 4.84 beats per min. The E-wave/A-wave ratio increased from 2.44 ± 0.33 to 3.05 ± 0.56. Normal sinus rhythm was maintained in all subjects (100%). Sinus tachycardia was observed in 65.00% of cats, transient PR interval shortening in 25.00%, and isolated premature atrial contractions in 15.00%. No pathological arrhythmias or significant conduction blocks were detected. Respiratory rate showed a minor increase from 38.05 ± 5.87 to 40.05 ± 5.96 breaths/min, while blood pressure and body temperature remained stable. Nebulized salbutamol demonstrates a high margin of cardiovascular safety in healthy cats. The preservation of normal sinus rhythm and clinically insignificant nature of the observed physiological changes support its continued use as a first-line bronchodilator in feline respiratory medicine.

Abstract Ocular ultrasonography is a safe, painless and non-invasive diagnostic tool that provides veterinarians with detailed images of the eye and surrounding structures. This study evaluated 30 clinically healthy Turkmen horses, divided into two groups as Group 1: under 36 months (3 males, 8 females), and Group 2: 36 months and older (8 males, 11 females). Significant differences in several ocular parameters were identified across different age groups in Turkmen horses. Specifically, the mean intercanthal distance, globe diameter, ciliary body volume and area, iris thickness, corpora nigra distance, volume and area, vitreous chamber and retinal/choroidal/scleral composite size demonstrated statistically significant variations between age categories. No significant differences were detected between sexes within any of the age groups for above measured parameters. Of the ocular parameters evaluated, only anterior chamber depth, central lens thickness and ciliary body thickness demonstrated statistically significant differences based on both sex and age. The average corneal thickness of the left and right eyes, as measured in sagittal and dorsal planes, was similar in both male horses under 36 months and those 36 months or older when compared to their respective female counterparts. No significant differences were observed between measurements of the left and right eyes, nor were there significant discrepancies between sagittal and dorsal measurements. These findings provided a baseline for understanding normal ocular ultrasonographic features in Turkmen horses and might aid in diagnosis and management of ocular diseases specific to this breed.

Abstract Tumors in cattle are uncommon, partly due to their relatively shorter lifespan, and vaginal neoplasms are rarely documented. Among vaginal and vulvar tumors, fibropapillomas are the most common, while leiomyomas, leiomyosarcomas, fibrosarcomas, and fibroleiomyosarcomas occur far less frequently. We describe the clinical presentation, surgical management, and pathological characterization of a vaginal fibroleiomyosarcoma in a 5-year-old Holstein cow. Clinical examination revealed a firm intravaginal mass attached to the dorsal wall. Surgical excision was performed under epidural anesthesia, followed by appropriate post-operative antibiotic and analgesic therapy. The cow recovered without complication, and no recurrence was observed during six months of follow-up. Macroscopically, the tumor measured 65.00 × 52.00 × 40.00 mm, and it was firm in consistency and gray in color. Histopathologically, it was composed of spindle-shaped neoplastic cells arranged in fascicles and bundles, displaying marked pleomorphism, blunt-ended nuclei, eosinophilic cytoplasm, and numerous mitotic figures. The stromal component showed variable collagen deposition, giving the lesion a biphasic fibromatous and leiomyomatous pattern. Immunohistochemically, neoplastic cells showed strong cytoplasmic positivity for α-smooth muscle actin and vimentin, confirming both smooth muscle and mesenchymal differentiation. Based on these findings, the tumor was diagnosed as a primary vaginal fibroleiomyosarcoma. To the best of our knowledge, this represents the second report of such a tumor in cattle and the first described in a Holstein cow. The case highlights the diagnostic value of combining histopathological and immunohistochemical analyses for accurate identification of rare bovine vaginal tumors.