IRANIAN JOURNAL OF VETERINARY SCIENCE AND TECHNOLOGY
Year:2018 | Volume:10 | Issue:2 |Papers Count:8

Despite the development of novel drugs and technologies in combating the infectious diseases, they remain as a global health challenge. The use of conventional antimicrobial drugs are always associated with problems such as antimicrobial resistance, adverse effects, and inefficient drug delivery. In this regard, the unique physiochemical properties of the nanoparticles have led to increase in the researches on nanoparticles and their application as promising antimicrobial products. Lipid nanoparticles (LNPs) are new carrier systems developed as an alternative to traditional nanoparticle vehicles. The solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLCs), lipid-drug conjugates (LDCs), Lipid-core nanocapsules (LNCs) and lipid-polymer nanoparticles (LPNs) are carriers with a lipid matrix showing advantages for different applications due to the use of biodegradable, and biocompatible lipids. LNPs have exclusive properties owing to their ultra-small size and high surface area, thereby, they are able to increase drug targeting, treatment efficiency and reduce the toxicity of antimicrobial drugs. LNPs are often used as sustained release systems, and they also used for improving drug bioavailability. It has been found that the composition and structure of LNPs are two critical factors that may influence their pharmaceutical performance in different body organs. This review focuses on the development of LNP systems for antimicrobial drugs delivery and gives an overview on the modern LNP-based therapeutic strategies against the infections. The mechanism of action and advantages of these nanoparticles as antibacterial, antifungal, antiviral and anti-parasitic agents are highlighted in this review.

The spread of antibiotic-resistant bacteria in many humans and animals has driven researches to identify and design novel antibacterial agents. In vitro inhibitory activity of (2E)-2-(4, 5-dihydro-4-oxothiazol-2-yl)-2-(thiazolidin-2-ylidene) acetonitrile against many bacterial pathogens has been proven in both veterinary and human medicine. In this study, its in vivo toxic effects was studied in mice. The median lethal dose (LD50) value of 239. 88 mg/kg was estimated using intraperitoneal injection in 8 groups of mice after 48 h treatment. Then, intraperitoneal injections of LD50 of oxothiazole solution into 4 other mice were done to evaluate histopathological changes in their liver and kidney tissues. The histopathological studies were identified as fatty change, hepatitis, necrosis and regeneration in liver, and fibrosis, necrosis, nephritis, hyaline cast and hyperaemia in kidney. In conclusion, the synthesized oxothiazole derivative causes renal and hepatic toxicity in mice at medium concentrations. The change of thiazole substituents and complexation may reduce its toxicity.

Avian influenza virus subtype H9N2 causes important economic losses in industrial poultry worldwide. Biosecurity and vaccination have not completely prevented the outbreak of avian influenza virus subtype H9N2 in poultry, and there are no appropriate medicines available. Onion is one of the plants used from the ancient times both as food and medicine. The purpose of this study was to evaluate the antiviral effects of aqueous extract of red and yellow onion against avian influenza virus subtype H9N2. First, a study was performed to evaluate the toxic effects of the extracts on the embryonated chicken eggs. For antiviral evaluation, three mixtures were prepared: mixture of the virus and the red onion extract, mixture of the virus and the yellow onion extract, and mixture of the virus and PBS, as a control group. The mixtures were separately inoculated to the chorioallantoic sac of the embryonated eggs after 2, 8 and 24 hours incubation at room temperature. Mortality rate and hemagglutination assay titers were recorded. The results indicated that the red onion extract decreases mortality of the embryos and the yellow onion extract increases the life of the embryos, and both of the extracts decrease HA titers. In conclusion, it seems that both extracts especially aqueous extract of the red onion not only destroys the avian influenza virus subtype H9N2, but also they probably decrease the propagation of the virus in the embryonated chicken eggs.

The aim of the present study was to evaluate the effect of adding tramadol to lidocaine for brachial plexus block in sheep. Six healthy, adult ewes weighing 41. 7 ± 3. 82 kg were used. Using an electrical stimulator, brachial plexus block was performed with lidocaine (4 mg/kg) (LID), lidocaine (4 mg/ kg)-tramadol (2 mg/kg) (LTL), and lidocaine (4 mg/kg)-tramadol (4 mg/kg) (LTH). All sheep received the three treatments with one-week interval. The final volume of administered solutions was adjusted to 0. 3 mL/kg. Time to the onset and duration of anesthesia as well as changes in heart rate, respiratory rate, and rectal temperature were determined. Time to the onset of sensory blockade and motor blockade was not significantly different among groups. The duration of sensory blockade and motor blockade were significantly longer in LTH (128. 3 ± 9. 7 and 151. 5 ± 21. 5 min, respectively) compared with those of LID (88. 6 ± 6. 5 and 110. 5 ± 21 min, respectively) and LTL (51. 6 ± 11. 8 and 89. 6 ± 22. 7 min, respectively). Although the onset of sensory blockade was longer than that of motor blockade in the three treatments, the difference was only significant in LTL. No significant differences were observed in heart rate, respiratory rate and rectal temperature among and within treatments. It was concluded that addition of tramadol (4 mg/kg) to lidocaine, without altering the onset, can provide more prolonged anesthesia than that of lidocaine in brachial plexus block in sheep.

This study sought to assess the levels of cardiac troponin I, as a resuscitation end point, along with oxygen delivery (DO2) and oxygen consumption (VO2) during resuscitation of dogs with experimental hemorrhagic shock using lactated Ringer’ s solution or 6% hydroxyethyl starch. After induction of anesthesia (control measurements), hemorrhagic shock was induced by rapid removal of blood to achieve a mean arterial pressure (MAP) of 40 to 50 mmHg within 30 minutes and then maintained in hypovolemic situation for additional 30 minutes (second and third stages of measurements). Afterward, the dogs were randomly assigned to two groups which received 20 ml/kg lactated Ringer’ s solution or 5 ml/ kg Hydroxyethyl starch, in four consecutive 15 minutes intervals (forth stage of measurements). One hour after the last resuscitation step, final measurements were performed. Hemorrhagic shock caused marked elevation in the levels of cTnI and reduction in DO2 and VO2 (p < 0. 05). Following resuscitation, a significant reduction was observed in the levels of cTnI and VO2 but a significant elevation was seen in DO2 levels (p < 0. 05), without significant differences between the groups (p > 0. 05). The results of this study proved that cTnI can be evaluated for better monitoring during fluid therapy in hemorrhagic shock, as a novel resuscitation end point.

Contagious ecthyma (CE) is a zoonotic skin disease of small ruminants, caused by an epitheliotropic parapoxvirus and has a worldwide distribution with significant economic importance. The objective of this study was to determine clinicopathlogic abnormalities in goats naturally infected with CE. Thirty two goats, 16 affected with CE and 16 normal healthy goats were used in this study. CE was confirmed by histopathology and PCR. Blood samples were collected from jugular veins for hematological and biochemical analysis. The PCV, WBC and neutrophil counts of CE affected goats were significantly higher than those in the unaffected goats (p < 0. 05). Serum biochemical analysis revealed significantly higher levels of BUN, glucose, MDA and iron concentrations as well as CK, AST, GGT and catalase activities in CE affected goats than healthy animals (p < 0. 05). The serum activity of catalase, SOD and GPx in goats with CE were significantly lower than those in normal goats. Creatinine concentration in serum of goats with CE was significantly lower than that in heathy ones (p < 0. 05). There was no significant difference in serum total protein, albumin, total and direct bilirubin, and cholesterol concentrations between CE affected and healthy goats. The alterations observed in hematological and biochemical parameters of CE affected goats could be related to weight loss, subnutrition, oxidative stress and pathological changes including inflammation and secondary bacterial infection. These findings could be useful for the management of cases of sheep and goats with CE.

Mastitis is the main disease in dairy farms that causes serious losses. The early diagnosis and specific treatment can prevent the spread of the disease and the economic losses. The aim of this study was to evaluate the accuracy of the latex agglutination assay for detection of the main bacterial mastitis agents. The antiserum against Staphylococcus aureus, Trueperella pyogenes, Streptococcus agalactiae and Escherichia coli were prepared from immunized rabbits. The couplings of antibodies to latex particles were optimized and after that, the limit of detection (LOD) of latex agglutination test was evaluated for detection of the mentioned bacteria. The detection limit for the Streptococcus agalactiae, E. coli, Staphylococcus aureus and T. pyogenes were respectively 1. 3×103, 2×107, 1. 58×104 and 5. 4×104 colony-forming unit per each milliliter of the bacterial suspensions. The prepared latex test has more sensitivity in the setting of phosphate buffered saline than in contaminated milk samples. This method can be used for the fast detection of the mentioned bacteria in bacterial cultures and milk samples. The latex agglutination test could be evaluated as a fast, cost benefit, and practical method in dairy farms.

The aim of this study was to evaluate the antioxidant potential of lemon pumace powder (peel and pulp), as an inexpensive and valuable source of nutrient in diet of common carp. Fish (60 ± 5 g) were divided randomly into four groups of 30 each. Group 1 fish were fed with basic diet, serving as the control. Fish in group 2 and 3 and 4 were fed the basic diet supplemented with 1. 5%, 3% and 5% lemon pumace powder, respectively. Results showed that growth performance including final weight, weight gain (WG), feed conversion ratio (FCR) and specific growth rate (SGR) significantly increased as compared to control. Malondialdehyde (MDA) values of muscle significantly increased as compared to control in all treatment groups and the decreeing effect of lemon pumace powder on malondialdehyde (MDA) values of kidney and liver was only significant in group 4, when compared with the control group (p < 0. 05). Protein carbonyl contents were significantly decreased in kidney and liver in group 3 and 4 as compared to control group and protein carbonyl of muscle significantly decreased as compared to control in all treatment groups. FRAP values of liver significantly increased only in group 3 as compared to control, and FRAP values of kidney and muscle significantly increased only in group 4 as compared to control (p < 0. 05). These data suggest that supplementation of 5% lemon pumace powder to be more effective than its lower levels in strengthening the antioxidant system against oxidative stress.