BACKGROUND: Blowfly (Lucilia sericata; Diptera: Calliphoridae) is an external parasites of domestic animals and the causative agent of myiasis, which is involved in the transmission of a  number of bacterial pathogens. Application of chemical insecticides is one of the most common methods for controlling this pest, which have recently been reported resistant populations of L. sericata to some insecticides. Therefore, identifying and recommending new and low-risk insecticides for humans and environment is of prime importance.OBJECTIVES: This research aimed to investigate the toxicity of insecticides deltamethrin, spinosad, pyridalyl, and pirimiphos-methyl on the third instar larvae of L. sericata.METHODS: In the present study, the bioassay tests were performed by immersion of larvae in concentrations of insecticides that caused 10 to 90% mortality of larvae, as a factorial experiment in a randomized complete block design. Additionally, the median lethal concentration (LC50)  was determined from the probit analysis of bioassay data for the studied insecticides.RESULTS: The results of analysis of variance and the comparison of the mean mortality (%) of third instar larvae were significant at the level of 1% probability. According to bioassay tests, the estimated LC50 values for deltamethrin, spinosad, pyridalyl, and pirimiphos-methyl were 186.49, 26.88, 85.08, and 134.97 mg L-1, respectively. Overall, the results revealed that spinosad and pyridalyl had the highest lethal effect on blowfly larvae while deltamethrin had less advers effects on this pest.CONCLUSIONS: Spinosad, as a relatively new insecticide, with very low toxicity towards mammals and other non-target organisms, showed the highest lethal effect on blowfly larvae and can be an appropriate alternative to older insecticides in controlling this pest.

BACKGROUND: Oxidative stress is believed to be one of the major causes of tissue damage in aquatic animals exposed to heavy metals. It leads to certain changes in the antioxidant and enzyme system. Given the fact that research on the effect of sub-acute toxicity of silver nitrate in shrimps is not very developed, the present study can be conducive to formulating the international standards of contamination of shrimps with silver nitrate.OBJECTIVES: The present study aimed to evaluate the toxic effects of silver nitrate on the changes in the antioxidant and enzyme systems of hepatopancreas, muscle and gills of Litopenaeus vannamei.METHODS: After acclimatization of shrimps, they were exposed to silver nitrate with concentrations of 0.0084, 0.021, 0.042 and 0.063 mg/L for 21 days. At the end of the experimental period, gill, muscle and hepatopancreas were sampled, and the changes in the antioxidant system (SOD, GPx and GST) and metabolic enzymes (ALT, ALP, AST and LDH) were examined.RESULTS: There was no significant difference in terms of SOD and GST activity in the gill and muscle of the exposed shrimps (P>0.05). However, GPx in treatment 4 increased significantly in gill and muscle while it saw a decrease in hepatopancreas (P<0.05). In hepatopancreas, GST significantly increased in treatments 3 and 4 (P<0.05) whereas SOD did not show any significant changes compared with other treatments (P>0.05). The metabolic enzymes of the muscle did not show any significant differences in any of the treatments (P>0.05), but in gill, the level of ALT in treatment 4 decreased significantly while the levels of AST and LDH in treatment 3 and 4 significantly increased (P<0.05). In hepatopancreas, the activity of ALT in treatments 2 and 4, AST in treatments 3 and 4, and ALP in all treatment except treatment 1 saw significant reduction. Nevertheless, LDH in treatments 3 and 4 had a significant rise (P<0.05).CONCLUSIONS: A significant increase in GST and LDH as well as a significant decrease in GPx and ALT, AST and ALP enzymes in the hepatopancreas revealed that the antioxidant and enzyme system of shrimps is further disturbed with the rise in silver nitrate concentration in the hepatopancreas compared to the gill and muscle.

BACKGROUND: Vanadium and zinc are identified as low-concentration elements in the body of living organisms with a wide range of activities. Their insulin-like activity, through regulating the metabolism of carbohydrates, lipids, and eliminating the secondary symptoms of the disease, clearly demonstrates the ability of these elements to improve diabetes.OBJECTIVES: The present study aimed to evaluate the effect of vanadium-zinc complex on the structural, functional, and oxidative stress changes in liver tissue in adult diabetic male rats.METHODS: Herein, we recruited 40 adult male rats with the same weight range. They were randomly divided into four groups of 10, namely control, diabetic, healthy mice receiving vanadium-zinc complex, diabetic mice receiving vanadium-zinc complex) and received this combination at the rate of 10 mg / kg once a day for 60 days by oral gavage. At the end of the course, following blood sampling, part of the liver tissue was removed from the body to measure oxidative stress and the rest for stereological and histological studies. The serum isolated from the animals was also used to measure liver tissue functional enzymes (aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase).RESULTS: The results of this research revealed that vanadium-zinc complex has no side effects on liver tissue in most case, but can greatly prevent structural damage to liver tissue by lowering blood glucose levels in diabetic rats and improving oxidative stress.CONCLUSIONS: Vanadium-zinc complex can be utilized with a certain mechanism in order to control blood sugar and inhibit oxidative stress. It could be regarded as an appropriate approach to preventing liver damage following chronic hyperglycemia in diabetic patients.

BACKGROUND: Major histocompatibility complex (MHC) encodes for highly variable molecules, most of which are responsible for foreign antigen recognition and activation of immune responses in the host. LEI0258 microsatellite, located in the poultry MHC region, is a suitable genetic marker for determining MHC haplotypes and genetic diversity in poultry.OBJECTIVES: Considering the fact that there is no report on the frequency and types of MHC alleles and population genetic analysis in Ross 308 poultry in Iran, the present study aimed to investigate the diversity of MHC haplotypes of Ross 308 broilers by LEI0258 microsatellite.METHODS: A total of 216 blood samples were collected from two productive herds of Ross 308 broilers. After extracting DNA of the blood samples and amplifying LEI0258 microsatellite alleles, genotyping of MHC haplotypes was performed using agarose gel electrophoresis and fragment analysis techniques.RESULTS: A total of seven alleles and 21 genotypes were identified for LEI0258 microsatellite in these two groups. the highest and the lowest frequencies belonged respectively to allele 385 bp (42.86 %) and allele 300 bp (4.33 %). Heterozygous 207/385 was found to be the dominant genotype in both populations. According to the similarity matrix analysis, there was an 84.56 % similarity between the two groups.CONCLUSIONS: The results obtained in this study revealed a high level of heterozygosity (85.71 % and 91.35 %) and deviation from Hardy–Weinberg equilibrium (P<0.0001) in these two Ross populations. Ross 308 broiler chickens had lower allelic diversity and higher genetic similarity compared to the native ones. These findings provided additional information on the use of MHC as a candidate gene marker in genetic improvement and resource conservation in broiler populations.

BACKGROUND: Meat is one of society's most important nutritional needs, the price of which is higher than other food groups. In recent years, the use of meat products has increased due to human lifestyle changes. Fraud in meat products occurs for various reasons, including the economic value of meat. Therefore, it is crucial to use fast and accurate methods of identifying these frauds.OBJECTIVES: The purpose of this study is to determine the unauthorized tissue by a histological method as well as to determine the unauthorized species used in meat products of factories in Hamadan province.METHODS: In the summer of 2021, fifty samples were collected from active production units of the Hamedan province that were available in the Hamadan city market and transferred to the laboratory for histological laboratory and animal species determination by PCR test. For the histology test based on the national standard 6103, the samples were subjected to fixation, passage (dehydration, clearing, impregnation with molten paraffin), blocking, sectioning, and H&amp;E staining. PCR method was used to determine the type of animal species used in the production of the collected samples.RESULTS: The results confirmed the presence of unauthorized tissues, including bone, cartilage (articular and respiratory cartilage), skin, and glandular organ in meat products. Also, PCR test results showed that chicken meat was found in 100% of the samples labeled with beef.CONCLUSIONS: The presence of illegal tissue and the use of chicken meat in products labeled as beef meat is evident in the sausages produced in Hamadan province.

BACKGROUND: Subclinical mastitis plays an important role in the economic losses of dairy cattle farms. Staphylococcus aureus is one of the most important causes of this disease. Treatment of this disease with synthetic antibiotics has complications like antibiotic resistance. Using herbal antibiotics can be an excellent way to reduce these side effects.OBJECTIVES: This study aimed to determine the minimum inhibitory concentration of alcoholic extract of olive leaf on Staphylococcus aureus isolated from milk of cows with subclinical mastitis to achieve herbal treatment.METHODS: This study was conducted on 175 Holstein female cattle. The milk samples of 60 cows were obtained with the sterilized method, and Subclinical mastitis-positive cases were determined using the California mastitis test. Staphylococcus aureus bacteria were isolated from positive samples by culture method, and the minimum inhibitory concentration of olive (Olea europaea L.) leaves alcoholic extract on isolated bacteria was determined by microdilution method.RESULTS: From 175 cows under study, 60 cows had a positive California mastitis test, and Staphylococcus aureus separated from milk samples of 14 cows. The minimum inhibitory concentration of olive (Olea europaea L.) leaves extract on this bacterium was 12000 ppm.CONCLUSIONS: Alcoholic extract of olive (Olea europaea L.) leaves has an antimicrobial effect on Staphylococcus aureus as a cause of mastitis. The minimum concentration required for this effect was 12000 ppm. Further studies on the impact of this plant on other bacterial causes of subclinical mammary inflammation in cows and investigation of the effective substances in the extract are needed.

BACKGROUND: The defects of the central nervous system caused by viruses are associated with tissue changes in certain areas of this system. OBJECTIVES: We conducted the current work to determine and categorize the pathologic pattern of central nervous system lesions in stillbirths and newborns small ruminants with neurological symptoms in Semnan province. METHODS: Primarily, we selected the affected animals and carried out systematic post mortem examination of lambs and kids. Subsequently, brain and spinal cords were completely removed. Processing, sectioning, and staining from different regions of the central nervous system was performed and 15 different regions of the brain and 10 different levels of the spinal cord were prepared. Subsequently, the histopathological study was performed and the observed lesions were arranged. RESULTS: This study was performed on 20 lambs and kids with nonsuppurative inflammatory lesions in the brain and spinal cord. In the gross examination of the brain and spinal cord, we observed 4 cases of arthrogryposis, 1 case of spinal cord hypoplasia, 2 cases of hydranencephaly, 2 cases of porencephaly, and 1 case of cerebellar hypoplasia. According to the presence of nonsuppurative inflammation in the brain and spinal cord, 20 positive cases were categorized into 4 groups. In the first 3 groups, the main lesion was nonsuppurative encephalomyelitis and the main lesion of the fourth group was nonsuppurative encephalitis. Accordingly, 6 cases in the first group had extensive and inclusive nonsuppurative inflammation in over 75%  of the brain and spinal cord sections; in the second group, five cases had multiple scattered nonsuppurative inflammation in 50% - 75% of the brain and spinal cord sections; in the third group, five cases had non-inclusive and focal nonsuppurative inflammation in less than 50% of the brain and spinal cord sections, and in the fourth group, 4 cases had nonsuppurative inflammation in the brain without lesion in the spinal cord. CONCLUSIONS: It seemed as though in each of the four pathological patterns, certain viral agents were responsible for the pathological changes.

BACKGROUND: Calf pneumonia is one of the most common diseases in dairy and beef herds. OBJECTIVES: To compare steroidal and non-steroidal anti-inflammatory drugs as adjunctive therapy in dairy calf pneumonia. METHODS: Forty calves less than six months of age diagnosed with calf pneumonia in dairy farms of Mashhad suburb were enrolled in this study based on the University of Wisconsin Calf Respiratory Scoring Chart. In this system, calves are scored based on factors such as nasal discharge, rectal temperature, cough, eye and ear staining. Calves should not have a history of any other disease. Moreover, factors such as age, sex, and severity of the disease were considered similar in distributing calves among different groups. These calves were divided into four treatment groups; all were treated with antibiotic florfenicol. The first group received dexamethasone, while dexaphenyl, phenylbutazone, distilled water were used in other groups. After 5 days, calves were examined and scored again and blood samples were taken. Complete blood count (CBC), fibrinogen, total protein, hapto-globulin and albumin measurements on blood samples before and after treatment were done. Repeated measurement ANOVA and Paired t-test were used for statistical analysis with the significance level of 0.05. RESULTS: The results showed that the degree of health, heart and respiratory rate, fibrinogen and total protein, Lymphocyte, N/L, TP-Fib/Fib ratio, MCV and MCHC significantly changed during the two sampling periods (p < /em>˂0.05), but there was no significant difference between the treatment groups (p < /em>˃0.05). Only the PCV factor and TP-Fib/Fib ratio was significant between groups (p < /em>˂0.05). CONCLUSIONS: Results indicate that in the treatment regimen of dairy calf pneumonia, the use of an anti-inflammatory drug, along with antibiotics and antibiotic treatment alone are not significantly different.

BACKGROUND: Peste des petitis (PPR) is a highly contagious viral disease with high incidence and mortality rate, which is endemic in the Middle East, Southwest Asia, and Africa. This disease has been causing economic losses in sheep and goat flocks in these areas. Studies have shown that environmental and host risk factors can influence the severity of PPR infection. OBJECTIVES: We conducted the present study to investigate the prevalence of PPR in small ruminants population of Garmsar city and its suburbs. Furthermore, the effect of host factors, including animal species, gender, and age, and environmental factors, such as sampling season, geographical area, and sampling location, were evaluated. METHODS: Blood samples of 180 sheep and goats were taken in spring, summer, and autumn and after centrifugation, serum samples were isolated. We measured antibody response using competitive enzyme linked immunosorbent assay (C-ELISA). RESULTS: The apparent and true prevalence of contamination in small ruminants of Garmsar and its suburbs ware 24.44 % and 23.91 %, respectively. The results revealed non significant relationships between animal species (p < /em>= 0.08), gender (p < /em>= 0.14), and age (p < /em>= 0.98) with PPR serum prevalence. Meanwhile, there was a significant relationship between season (p < /em>= 0.03), geographical area (p < /em>= 0.0004), and sampling location (p < /em>= 0.0001). In addition, the odds ratio of PPRV infection in autumn was 2.62 (95% CI: 0.06 – 6.02; p < /em>< 0.05) times more than that of other season and in the south-eastern of Garmsar, it was 6.71 (95% CI: 3.01-17.60; p < /em>< 0.05) times more than that of other geographical regions. The odds ratio of PPRV infection in the Mahmood Abad village was 63.63 (95 % CI: 12.14 – 132.93; p < /em>< 0.05) times higher than that of other villages. CONCLUSIONS: According to the obtained findings, PPR was proven to be an endemic disease in Garmsar and its suburbs and the environmental risk factors have a greater impact on the seroprevalence of disease than host risk factors. Therefore, in order to control the disease in endemic areas, further attention should be paid to environmental risk factors and minimizing the risk of epidemics through vaccination at sensitive timescales and areas before high-risk environment changes.

BACKGROUND: It is possible for Sex reversal of eggs with female embryo using anti-aromatase agents, and the hatchlings have an improved performance. OBJECTIVES: The present study was conducted to survey the effect of in ovo injection of 0.1 mL Nettle (Urtica dioica) and mushroom extracts and Fadrozole hydrochloride as anti-aromatase agents  on sex differentiation of broiler chickens. METHODS: 366 fertile eggs from Ross 308 strain broiler breeders were divided into 4 groups. At the beginning of the fifth day of incubation in ovo injection operation was carried out. A control group was injected with 0.1 mL distilled water. The hatched chickens were then reared in a completely randomized design with 4 treatments and 6 replicates for 42 days. RESULTS: In ovo injection of 0.1 mL of fadrozole hydrochloride, mushroom and nettle extracts led to 100, 66.67 and 37.5 percent sex reversal, respectively (p < /em><0.05). During the whole of the experimental period, daily feed intake and daily weight gain of chickens of fadrozole hydrochloride and mushroom extract groups were higher than those on the control and nettle extract (p < /em><0.05). Fadrozole hydrochloride reduced levels of serum triglyceride and VLDL (p < /em> <0.05), but there was no significant difference in cholesterol, HDL-cholesterol and LDL cholesterol levels (p < /em>> 0.05). White blood cells and hematocrit percentage were not affected by experimental treatments (p < /em>> 0.05). Compared with other treatments, in ovo injection of mushroom extract caused a significant increase in the number and average diameter of muscle fibers (p < /em><0.05). CONCLUSIONS: The findings of this study confirm the significant anti-aramatogenic properties of the mushroom extract and the positive effect of in ovo injection of  mushroom extract on the sexes reversal and improvement in performance of broiler chickens.