Veterinary Research Forum

Abstract Pneumonia remains a significant economic burden on the small ruminant industry. Excessive inflammation, oxidative stress, and alterations in copper and zinc can accompany pneumonia. As these micro-nutrients play crucial roles in immune function and anti-oxidant defence, modulating their levels may influence the disease progression. This study aimed to investigate the effects of different therapeutic regimens on copper and zinc status in lambs with pneumonia. Twenty lambs with pneumonia were randomly assigned to four treatment groups: oxytetracycline and tylosin (OT), OT plus vitamin B1 (OTVB1), OT plus vitamin C (OTVC), and OT plus vitamin B1 and vitamin C (OTVB1C). A control group received only distilled water. Blood samples were collected on days 1, 3, 6, and 14 for subsequent assessment of plasma copper and zinc concentrations. While the control group maintained stable levels, the pneumonic groups exhibited varying degrees of changes. Plasma copper concentrations increased significantly in all pneumonic groups compared to the control group throughout the study. The OT and OTVB1C groups had the highest number of lambs with increased copper level. Plasma zinc concentrations decreased significantly in the OT and OTVB1 groups, with the lowest levels in the OTVB1 group on day 3. The OTVC group mirrored the control group with stable levels. The OTVB1C group, compared to the other groups, showed a more persistent reduction. These findings suggest that the effects of the various treatment regimens on plasma copper and zinc levels may be complex and time-dependent.

Abstract Echocardiography is a noninvasive, highly sensitive method for evaluating heart disease in veterinary medicine, crucial for measuring cardiac structures and functions. Despite its importance, limited data exist on sheep, particularly the Ghezel breed, a significant breed in Iran. This study aimed to establish normal echocardiographic values for Ghezel sheep, providing reference data for both clinical and research applications. We evaluated 15 healthy Ghezel sheep with a mean age of 16.50 ± 1.80 months and a mean weight of 42.69 ± 4.73 kg. Comprehensive clinical exams, biochemical and hematological tests and color Doppler echocardiography were performed. Descriptive results from standard right and left parasternal views in both longitudinal and transverse planes were obtained and compared to existing studies. The study successfully established pulse wave Doppler reference values for the Ghezel breed. These findings could be used in diagnosing heart disease in Ghezel sheep and would be beneficial in future research particularly in sheep used as an animal model for translation in human cardiac studies.

Abstract Gastrointestinal motility disorders include increased or decreased movements. Other studies have shown that herbal components, for example, essential oils can modify the increase and decrease of gastrointestinal movements of ruminants. The 1, 8-cineole being obtained from the essential oil of many plants has several effects. The present study has investigated the effect of 1, 8-cineole on the contractility of bovine ileum smooth muscle. The experiment was performed on the circular smooth muscle of ileum samples taken from slaughtered cows in the organ bath. Seven cumulative concentrations of 1, 8-cineole from 1.00 to 1,000 µg mL^-1 were added to tissue samples. The used solution was Tyrode’s solution aerated with a mixture of 95.00% oxygen and 5.00% carbon dioxide, and the temperature was set at 37.00 ˚C. The effects of 1, 8-cineole on baseline contractions and three induced contractions with barium chloride, potassium chloride, and carbachol were investigated. The effects of 1, 8-cineole, and verapamil (standard calcium channel blocker) on calcium channels were assessed. The results revealed that 1, 8-cineole significantly inhibited spontaneous contractions as well as all spasmogen-induced contractions. The 1, 8-cineole exerts its myorelaxant properties by inhibiting calcium channels in smooth muscle. It seems that 1, 8-cineole has a good potential for producing antispasmodics or gastrointestinal motility modulators in veterinary medicine.

Abstract Gastrointestinal motility disorders can occur as either increased or decreased movements. Studies have shown that herbal ingredients such as essential oils can modify the increase and decrease of gastrointestinal movements of ruminants. Cinnamaldehyde at room temperature is an oily yellow liquid which is obtained from the steam distillation of the oil of cinnamon bark. It bears carminative activity and gastrointestinal, antimicrobial, and vasodilatory effects. This study examined the effects of cinnamaldehyde on the contraction of circular smooth muscles of abomasal fundus and the antrum, duodenum, and ileum of healthy cows using an in vitro approach. The results indicated that cinnamaldehyde had relaxant effects on the basal tonus and contractions caused by barium chloride (BaCl₂) and carbachol (CCh) in these tissues dependent upon concentration and the origin of the smooth muscle. These effects were more prominent in the ileal smooth muscle preparations than in other tissues. This substance in the smooth muscle preparations of the abomasal fundus not only had no significant effect on the basal tonus, but also significantly increased the contractions caused by barium chloride at low concentrations. Study of the mechanism of action showed that, similar to verapamil, cinnamaldehyde applied its relaxation effect by blocking the calcium channels. The results showed that cinnamaldehyde possessed a spasmolytic effect mediated through blockage of the calcium channels, which may provide a pharmacological base to its medicinal use for diarrhea and spasms.

Abstract Echocardiography is a non-invasive method of cardiac evaluation in most species. Echocardiographic reference parameters are poorly documented in sheep and not documented in Ghezel sheep. The purpose of this study was to determine reference ranges of normal echocardiographic parameters using two-dimensional and M-mode techniques in Ghezel sheep. In 15 healthy female Ghezel sheep aged between 15 and 18 months, echocardiography was performed in standing position from left and right parasternal approach focused at 3^rd - 5^th intercostal spaces using a 2.50 - 5.00 MHz phased array transducer. The following parameters were measured in two-dimensional echocardiography: left atrial diameter (LAD), mitral valve annulus (MVA), aortic sinus (AoS), aortic valve (AoV), pulmonary sinus (PuS), and pulmonary valve (PuV); and in M-mode echocardiography: interventricular septum (IVS), left ventricular internal diameter (LVID), left ventricular free wall (LVFW), right ventricle free wall (RVFW), right ventricle internal diameter (RVID). Calculated variables included the ratios LAD/Ao and Pu/AoS, and the fractional shortening (FS), end diastolic volume (EDV), end systolic volume (ESV), ejection fraction (EF), stroke volume (SV) and cardiac output (CO) of the left ventricle. In conclusion, echocardiographic parameters could be reliably assessed in Ghezel sheep and our study provided some normal echocardiographic reference ranges that might be useful in proper identification, visualization, and measurements of cardiac structures. Such findings could be useful to assess and to diagnose the specific heart diseases in sheep practice and also for experimental studies in sheep as an animal model used for research purposes in cardiovascular studies of human.

Abstract The present study was conducted to evaluate the effects of different doses of haloperidol (HP) on induction of oxidative stress in blood and liver cell degeneration in comparison with influences of HP pre-treatment on inflammatory process induced by intraperitoneal (IP) administration of lipopolysaccharide (LPS). One hundred twenty male albino Wistar rats were randomly divided into eight groups (15 in each), including: Control group, LPS group, three groups as HP administration in three divided doses (0.50, 1.00 and 2.00 mg kg^-1), and three treatment groups that HP was administered in three doses (0.50, 1.00 and 2.00 mg kg^-1) prior to LPS administration.Concentrations of malondialdehyde, activities of antioxidant enzymes including glutathione peroxidase, superoxide dismutase and also the levels of tumor necrosis factor-alpha and interleukin 1-beta were measured in blood and serum. In addition to liver histopathological changes evaluation, hepatic silent information regulator of transcription 1 (SIRT1) and phosphorylated-nuclear factor-κB (p-NF-κB) levels were quantitated. Our findings indicated that sole administration of HP (particularly higher doses) can induce oxidative stress in blood and cell degeneration in liver, while it can attenuate inflammatory process induced by LPS administration presumably via SIRT1 up-regulation and preventing the induction of p-NF-κB. The oxidative and degenerative effects of HP and its impact on inflammatory status were completely dose- dependent according to our results. The possible anti-inflammatory effects of HP may affect reparative mechanisms and hepatic cell degeneration. However, the influences of HP on immune system need further investigations and its higher doses should be administered cautiously especially in patients with immune system dysfunctions.

Abstract To evaluate the effect of intravenous infusion of a soybean based lipid emulsion (Lipovenoes 10%) on some blood constituents in sheep, a replicated 2 × 2 Latin square design experiment was conducted in four clinically healthy ewes. Lipid emulsion (LE group) or normal saline (NS group) was infused intravenously at a rate of 0.025 mL kg^-1 per min for 6 hr and the concentrations of blood triglyceride, glucose, insulin, calcium, magnesium, phosphorous, sodium and potassium were measured before (baseline) and then at timepoints 2, 4, 6, 12 and 24 hr after infusion. Compared to the baseline values and/or NS infusion, LE infusion resulted in a significant increase in the concentrations of triglyceride (p < 0.001), glucose (p < 0.01), calcium (p < 0.05), phosphorous (p < 0.01) and a significant decrease in insulin (p < 0.001) and magnesium (p < 0.05) concentrations. Compared to the baseline value, the homeostasis model of insulin resistance (HOMA-IR) index increased (p < 0.001) at timepoints 2 and 4 hr and abruptly decreased at timepoint six hr (p < 0.01) following LE infusion. In LE group, HOMA-IR values were significantly (p < 0.001) higher than those for NS group at timepoints 2 and 4 hr after infusion. Neither treatment nor time influenced serum sodium and potassium concentrations (p > 0.05). In conclusion, intravenous infusion of Lipovenoes temporarily influenced some blood constituents. Increased triglyceride concentrations were associated with an increase in HOMA-IR values indicating a state of insulin resistance. No remarkable adverse effect was observed following LE infusion and lipid based emulsions can be safely used in ruminants not suffering from extensive lipid mobilization.

Abstract Auto-reactive cells-mediated immune responses are responsible for the current tissue damages during autoimmunity. Accordingly, functional modulation of auto-reactive cells has been a pivotal aim in many of recent studies. In the current study, we investigated the possibility for insertion of regulatory molecules onto auto-reactive cells through exosomal nano-shuttles as a novel approach for phenotype modification of auto-reactive cells. The exosomes were isolated from supernatant of mesenchymal stem cells culture. Resultant exosomes co-cultured with lymphocytes were harvested from established EAE mice in the presence of antigenic MOG35-55 peptide. After 24 hr, insertion of exosomal tolerogenic molecules (PD-L1, TGF-β, galectin-1) onto auto-reactive cells were explored through flow cytometry. The potency of exosomal inserted membrane molecules to modulate phenotype of auto-reactive lymphocytes was assessed upon ELISA test for their-derived cytokines IFN-γ and IL-17. Incorporation of exosomal molecules into lymohocytes’ membrane was confirmed by flow cytometric analyses for surface levels of mentioned molecules. Additionally, the decreased secretion of IFN-γ and IL-17 were detected in exosome pre-treated lymphocytes upon stimulation with MOG peptide. Mesenchymal stem cells -derived exosomes showed to be efficient organelles for insertion of bioactive tolerogenic molecules onto auto-reactive cells and modulation of their phenotypes.

Abstract This prospective study aimed to compare the intraosseous (IO) and intravenous (IV) effects of propofol on selected blood parameters and physiological variables during general anesthesia in rabbits. Thirty New Zealand White rabbits were studied. Six rabbits received IV propofol (group 1) and another 6 rabbits, were injected propofol intraosseously (Group 2) for 30 minutes (experimental groups). Rabbits of the third and fourth groups received IV and IO normal saline at the same volume given to the experimental groups, respectively. In the fifth group IO cannulation was performed but neither propofol nor normal saline were administered. Blood profiles were assayed before induction and after recovery of anesthesia. Heart and respiratory rates, rectal temperature, saturation of peripheral oxygen and mean arterial blood pressure were recorded. Heart rate increased significantly 1 to 5 minutes after induction of anesthesia in experimental groups (P < 0.05). Although mean arterial blood pressure decreased significantly from baseline, values remained above 60 mm Hg (P < 0.05). Respiratory rate decreased significantly in experimental groups, but remained higher in group 2 (P < 0.05). The lymphocyte count decreased significantly in group 1 (P < 0.05). The concentration of alkaline phosphatase in all rabbits, aspartate aminotransferase and gamma-glutamyl transferase in the first group and gamma-glutamyl transferase in the third group increased significantly (P < 0.05). Total bilirubin decreased significantly in group 2 (P < 0.05). All measured values remained within normal limits. Based on the least significant physiological, hematological and biochemical effects, the IO injection of propofol appears to be safe and suitable method of anesthesia in rabbits with limited vascular access.

Abstract Oxygen is an essential part of the most important metabolic pathways in aerobic organisms. Oxygen delivery is merely dependent on blood, rendering blood loss a devastating event. Traumatic pre-hospital liver bleeding is a major cause of early trauma deaths in human and animals, with no established therapeutic method yet. Increasing intra-abdominal pressure (IAP) has been shown to reduce liver bleeding by half. Although reduction of blood loss could be in favor of blood oxygen delivery, however, the complex interaction between increased IAP and respiratory mechanics during severe hemorrhagic shock remained unclear. We used a novel model of liver trauma in 16 rabbits and randomly assigned them to either normotensive abdomen group or increased IAP by fluid infusion (HA) groups (n=8 each). Liver size and the amount of liver injury were evaluated. Various blood oxygenation parameters were recorded. Both groups were identical in terms of the liver size and injury. The HA group had significantly lower shock index. Arterial oxygen capacity and oxygen content were higher in the HA group. No significant statistical difference was seen between groups in terms of abdominal perfusion pressure; alveolar pressure of oxygen; dissolved oxygen in blood plasma; alveolar to arterial oxygen tension gradient; arterial to alveolar oxygen pressure ratio; the ratio between partial pressure of arterial oxygen and fraction of inspired oxygen; and respiratory index. In conclusion, the novel therapeutic method of increasing IAP by fluid infusion in a rabbit model of liver hemorrhage preserved blood oxygenation better than the classic therapeutic method.

Abstract The effect of inclusion of garlic essential oil (EO) at 33, 66 and 100 μg mL-1, raw garlic (GAR) at 5, 10 and 15 mg mL-1 and monensin (MON) at 7.5 μg mL-1 of incubation medium on organic matter digestibility (OMD) was studied with in vitro gas production, ANKOM daisyII and conventional in vitro (IVOMD) methods. The material was incubated with sheep ruminal fluid and the experimental design was a completely randomized design. Cumulative gas production was recorded at 0, 2, 4, 6, 8, 12, 16, 24, 36, 48, 72 and 96 hours of incubation. Conventional in vitro OMD was determined after 48 hours incubation in acid and pepsin solutions. Samples for DaisyII OMD prepared according to the operating instructions supplied by ANKOM® Tech. Co., Fairport, USA. Compared to in vitro dry matter digestibility (IVDMD), DaisyII and gas production techniques overestimated (P < 0.05) OMD. The addition of EO and MON reduced (P < 0.05) the organic matter (OM), neutral detergent fiber (NDF), acid-detergent fiber (ADF) digestion, and gas production volume. The potential of gas production and rate of gas production for EO and MON were the lowest; however, these variables were higher for GAR supplemented groups. It was concluded that raw garlic could be of great interest for its usage as a modulator of ruminal fermentation.