فصلنامه دامپزشکی ایران
سال بیست و یکم شماره 87 (تابستان 1404)

The application of silver nanoparticles (AgNPs) in aquaculture has received considerable attention in the recent years due to their antimicrobial, antifungal, and antiviral properties, as well as their potential to modulate the immune system of aquatic organisms. Although biologically synthesized nanoparticles are considered environmentally friendly due to the use of natural compounds in their production, it is essential to evaluate their potential effects on aquatic organisms. This study aimed to investigate the impact of silver nanoparticles (AgNPs) biosynthesized by the macroalga Cystoseira indica on the immune parameters of common carp (Cyprinus carpio). The fish were exposed in the laboratory for 14 days to three sublethal concentrations of AgNPs corresponding to 10%, 25%, and 50% of the LC50. Immune indices including lysozyme activity, complement activity, respiratory burst, peroxidase activity, white blood cell count, total protein, and immunoglobulin levels were assessed on days 1, 3, 7, and 14. Transmission electron microscopy revealed that the synthesized nanoparticles were spherical with an average size of 42.31 nm. The results indicated that, compared to the control group, exposure to 25% LC50 significantly increased lysozyme activity but decreased complement, respiratory burst, and peroxidase activities on day 14. Additionally, the lysozyme activity significantly reduced in the fish exposed to 50% LC50 on day 14. White blood cell counts increased significantly at all exposure concentrations relative to. Although total protein and immunoglobulin levels exhibited some fluctuations, no significant differences were observed compared to the control group. The findings indicated that only 25% LC₅₀ concentration of silver nanoparticles had a measurable effect on the immune indices of common carp, whereas other concentrations produced no significant alterations, and therefore no clear concentration-dependent trend was detected.

Pollution caused by heavy metals such as lead (Pb), cadmium (Cd), and arsenic (As), particularly due to industrial activities and poor management practices, poses a significant threat to human and animal health. This study evaluates the impact of nutritional management, herd size, and distance from industrial areas on heavy metal concentrations in samples of milk, water, animal feed, feed supplements, manure, and hair from 30 dairy farms located in Isfahan Province. Samples were collected from dairy farms with diverse characteristics, and the concentrations of heavy metals were measured using Atomic Absorption Spectroscopy (AAS). The results indicated that regarding nutritional management, 30% of the farms were rated as poor (Level 1), 50% as moderate (Level 2), and 20% as good (Level 3). The average scores for nutritional management were 45% for Level 1, 70% for Level 2, and 90% for Level 3. Larger herd sizes (over 600 heads) were associated with an increase in cadmium concentrations in manure (P=0.041), while poor nutritional management was significantly correlated with higher lead concentrations in milk (P=0.032). Additionally, the concentration of arsenic in animal feed was influenced by proximity to industrial areas (r=0.019, P=0.67). The median lead concentration in milk was 0.028 mg/L, which exceeds the permissible limit of 0.02 mg/L. The Lead levels in feed were measured at 1.98 mg/kg, cadmium in manure at 0.06 mg/kg, cadmium in hair at 0.102 mg/kg, and arsenic in feed at 0.62 mg/kg, all of which were below the permissible limits. The poor quality of animal feed significantly contributes to the increased concentration of lead in milk. Improving management practices and utilizing high-quality feed resources ara essential. It is recommended that continuous monitoring of the quality of food and water resources should be conducted to reduce the risks associated with heavy metals and ensure public health.

This study aimed to determine the effect of adding dexamethasone topically and intravenously on the onset and duration of sensory and motor blocks following brachial plexus block in sheep. In the present study, 20 adult female Arab sheep with an average weight of 32.9 ± 3.4 kg were used. To provide a brachial plexus block, the sheep were randomly assigned to one of three treatments of lidocaine (LID, 4 mg/kg), topical lidocaine- topical dexamethasone (LIDEXL, 4 mg/kg and 8 mg), and topical lidocaine- intravenous dexamethasone (LIDEXV, received 4 mg/kg and 8 mg). In the third group, dexamethasone was injected intravenously 10 minutes before anesthesia application. To identify the nerves, an electrical nerve stimulator was used. With nerve stimulation, the contraction and movements of the limbs were observed, and the drug was injected into the site until the limb movement stopped. The results showed that the onset of radial nerve block in the LIDEXL group was significantly lower than that of lidocaine alone. The duration of sensory and motor blocks was 68.11 ± 23.67 and 75.00 ± 30.41 minutes in the LID group; 59.6 ± 18.12 and 81.17 ± 20.90 minutes in the LIDEXL group, and 62.58 ± 16.55 and 64.40 ± 16.83 minutes in the LIDEXV group. No significant difference was observed between the groups. According to the results, adding dexamethasone topically and intravenously to lidocaine does not affect the onset or duration of sensory and motor nerve blocks following a brachial plexus block in sheep.

Ultrasonography is an optional method to evaluate the urinary system, which can be used to check the tissue and dimensional changes of kidneys. This technique is used to diagnose kidney diseases and changes in kidney size following treatment. The measurement of kidney can make it possible to observe more length of renal vessels and diverticula, from the dorsal view or taking transverse views. The aim of the present study was to evaluate the influence of positioning on measurement of renal dimension and their correlation to length of lumbar (L) vertebrae and abdominal aortic (AO) diameter by ultrasonography. The survey was conducted on twenty natives, adult healthy dogs. Renal length (L), width (W), height (H) and volume were measured in right lateral recumbency (RLR) and dorsal recumbency (DR) for the left kidney (LK), and in left lateral recumbency (LLR) and (DR) for the right kidney (RK) by ultrasonography. The aortic diameter and Length of the L5 and L6 were measured by ultrasonography and L2, L3 and L4 by radiography. Ratios were also calculated between dimensions of kidneys and lumbar vertebrae. Based on the paired sample t test, length and width of both kidneys were significantly larger than DR in RLR and LLR, while the height of the right kidney was significantly smaller than DR in LLR. There was no significant difference between the heights of left kidney in both positioning. There was a direct significant correlation between renal dimension with AO and vertebral length. Kidney length had the best Pearson correlation coefficient. There was no significant difference between renal dimension ratio and vertebral length. The ratio means of both left and right kidney length to L2 was obtained, 2.2 and 2.3, to L5, 2 and 2.1 and to AO, 7.3 and 7.3, respectively. In conclusion, the findings of the present study showed that the imaging mode had an effect on kidney dimensions. Therefore, it is necessary to compare kidney dimensions with the same imaging mode, in repeated ultrasonography of an animal.

The aim of this study was to compare the quality of anesthesia, duration of anesthesia, quality of recovery, pain assessment, vital signs and some hematological and biochemical factors following IO injection of midazolam and ketamine compared to IV injection. Six mixed-breed adult female dogs with mean weight of 21.76 ± 1.49 kg were selected.  Thirty minutes after intramuscular injection with acepromazine (0.05 mg/kg) and morphine (0.5 mg/kg) for sedation, the quality of sedation was scored and the right cephalic vein for fluid therapy and in the IV group, cephalic vein of the forelimb was catheterized to inject the drug. In the IO group, the left tibia was prepared for injection and after perforation of the bone, anesthetics {midazolam (0.375 mg/kg) and ketamine (10 mg/kg) were injected into the bone marrow. According to the performed studies, the anesthesia times in the two methods of IO and IV injection were not significantly different. In both methods, induction, maintenance of anesthesia and recovery were performed smoothly without any stress. By examining the results of the parameters measured in this study such as heart rate, respiration rate, body temperature, saturation of hemoglobin with oxygen, exhaled carbon dioxide, and recovery time, different stages of anesthesia and sedation quality, induction of anesthesia and recovery, significant differences were not found between the two groups. In the study of blood platelets, only a significant difference was observed in the total number of red blood cells and white blood cells in the blood sample after recovery between the IV group and to the IO group. There was no statistically significant difference in blood glucose and cortisol levels between the two groups in blood biochemical studies. Therefore, according to the results of this study, it can be concluded that IO injection of midazolam-ketamine in terms of lack of access to vein is a rapid and effective method of induction of general anesthesia in dogs.

Lameness as one of the significant and common issues in dairy cows, has considerable economic and health impacts on dairy farms. The use of footbaths with various antibacterial agents is a key strategy in many livestock approaches to control infectious hoof diseases. Numerous studies have shown that regular footbaths are associated with a lower prevalence of lameness. In the present study, 12 dairy farms with more than 100 lactating cows were included and then divided into two groups (less than 200 cows and more than 200 cows). Data related to the dimensions of the footbaths (length, width, and depth) and aspects related to the management of footbaths, such as the type of disinfectant and the frequency of refreshment, were recorded and compared with global standards. The results indicated that only half of the farms had footbaths, most of which footbaths did not meet standard dimensions. The average length, width, and depth of the footbaths were 225.61 cm, 128.96 cm, and 11.55 cm, respectively, which significantly differed from the minimum global standards (length: 350 cm, width: 60 cm, and depth: 15 cm). The prevalence of clinical lameness (scores 4 and 5) was reported to be 14.5% across all farms. However, no significant correlation was found between the presence and/or absence of footbaths and the prevalence of clinical lameness (Spearman’s rho, P-value=1.00). This study indicated that despite the key role of footbaths in preventing and controlling infectious hoof diseases, the proper design and management of footbaths in the studied farms are not adequately addressed. The findings emphasize the need for improved footbath design, using appropriate disinfectants, and training of workers to reduce the prevalence of lameness. Attention to standardizing footbaths and implementing scientific protocols can significantly enhance the health and productivity of livestock.

Veterinary science has so far focused mostly on the study of domestic animals, while reptiles, especially turtles, have received less attention. This is despite the fact that nowadays the use of reptiles, especially turtles, as pets and laboratory animals is increasing. Considering the proof of pathogenicity and the presence of parasites in these animals, it seems necessary to adopt appropriate treatment approaches for them. Due to the toxicity of avermectin and the resistance of nematodes to fenbendazole in turtles, levamisole is the chosen anti-parasitic drug in these animals. This study was conducted with the aim of evaluating the effect of levamisole at a dose of 10 mg/kg body weight as intravenous and subcutaneous injection on some oxidative stress factors in Caspian tortoises. The present study was conducted on 27 Caspian turtles with an average weight of 1.09 kg in 3 groups. The first group received Levamisole intravenously, but the second group received subcutaneously, in the same line the third group was the control group. Blood sampling was done at 7 different times during 24 hours at 0.5, 1, 2, 4, 8, 12 and 24 hours after drug administration. The results showed that the amount of malondialdehyde factor and catalase and superoxide dismutase enzymes in the serum of turtles treated with intravenous and subcutaneous levamisole have significant differences compared to the control group. While the total antioxidant capacity of the groups receiving the drug compared to the control group did not show a significant difference, which indicates the overall balance of the oxidant and antioxidant status so, it can be considered as one of the positive effects of the use of this drug in Caspian turtles. The results of the present study showed the efficient effect of levamisole as an antiparasitic drug with antioxidant properties that helps reduce oxidative stress.

Anaplasma is one of the obligate intracellular microorganisms that infect erythrocyte of mammals, especially ruminants. Considering the important role of Anaplasma marginale (A. marginale) for anaplasmosis in cattle, several studies have shown infection with this pathogen in other livestock species, but there is no information about its infection status and pathogenicity in Najdi goats. Therefore, the present study aimed to investigate the molecular and hematological factors of A. marginale infection in Najdi and native goats in Ahvaz city. To do it, blood samples were collected from 150 apparently healthy (76 Najdi and 74 native) goats from 6 herds in suburb of Ahvaz city, and infection with A. marginale was investigated by hematological and PCR methods. In the blood smear microscopy examination anaplasma-like intra-erythrocyte inclusion bodies were diagnosed in 22.4% and 29.7% of Najdi and native goats, respectively. The whole blood PCR also revealed A. marginale infection in 27.6% and 32.4% of Najdi and native goats, respectively. There was no statistically significant difference between the values ​​of hematological indices in the infected and non-infected goats. Multispecies husbandry and grazing were observed in all studied goat herds. Considering the lack of significant difference in the hematological parameters in the infected and non-infected goats, it seems that infected goats are important as a reservoir for A. marginale. The infection with A. marginale in the studied goats may be affected by the simultaneous rearing of different livestock species.