BACKGROUND: Ovine pulmonary adenocarcinoma, also known as jaagsiekte, is a chronic, contagious, and transmissible lung cancer. It is prevalent in ovine spp while rarely occurring in caprine with long incubation period. The disease is mostly observed in older animals (over 2 years old).OBJECTIVES: The present study aims to determine the prevalence of the disease based on histopathological diagnosis and investigate its correlation with age and sex in the slaughtered local sheep in Garmsar (Semnan province).METHODS: Herein, the lungs of 9030 slaughtered sheep are morphopatthologically examined for the presence of ovine pulmonary adenocarcinoma.RESULTS: Based on the morphopathological examination, ovine pulmonary adenocarcinoma was observed in the lungs of 438  (4.87 %) out of 9030 sheep. That said, 250 indicated the classical form, as firm, white to grayish coalescing masses mostly in the cranio-ventral lobes; this form is associated with wet cut surface and frothy fluid in the airways. The remaining 188 sheep showed the atypical form, as small, clear demarcated nodules mostly in diaphragmatic lobes associated with dry cut surface and minor fluid in the airways. Almost similar histopathological changes were seen in the two forms. An acinar or papillary growth of neoplastic cells in the alveoli and polypoid proliferation of bronchiolar epithelium were observed in both forms. However, there were variable amounts of connective tissue, and infiltration of lymphocytes and plasma cells in the interstitial tissue of the affected alveoli and no metastatic lesion in the lymph nodes. The peribronchial and peribronchiolar lymphoid aggregates were consistent features in most of the cases studied.CONCLUSIONS: The findings of the present study, as the first report of ovine pulmonary adenocarcinoma in sheep from Garmsa county, revealed the higher prevalence of this disease compared to that reported in previous reports in the country. Moreover, according to the obtained results, atypical and classical forms represented different stages of a single disease spectrum.

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: 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.

In bovine tuberculosis caused by Mycobacterium bovis, cattle are known as the main host, and sheep are relatively resistant. Sheep become infected only when there is very close contact between cattle and sheep or when the mycobacterium is abundant in the environment. In the present study, a case of generalized tuberculosis was reported in the sheep of the Sanandaj slaughterhouse.The examined animal carcass was transferred from the slaughterhouse to the University of Kurdistan microbiology laboratory and was dissected under complete health safety conditions. In the carcass examination, necropsy lesions (generalized tubercular granulomas) were visible in different organs and mediastinal lymph nodes, bronchioles, mesentery, and liver portal system. These lesions were seen in the lymph nodes of different body parts, including the lung, liver, digestive system, reproductive system, bladder, and different muscles, including the peritoneal muscle, diaphragm muscle, and abdominal muscles.Diagnostic tests included clinical observations, Ziehl-Neelsen staining for Mycobacterium bacteria, and polymerase chain reaction (PCR) molecular technique. In Ziehl-Neelsen staining, Mycobacterium acid-fast bacilli were seen in red color on the pale blue background of the slide. Also, the product of 499 base pairs was amplified in the specific PCR reaction, which confirmed Mycobacterium bovis.The present report shows that Mycobacterium bovis strains present in the region can be transmitted to sheep and cause disease with severe clinical symptoms. This report is critical, particularly for mixed cattle and sheep farming. Since cattle and sheep are kept together in many breeding farms in Kurdistan province, special attention was paid to the possibility of transmission of bovine tuberculosis to sheep and humans.

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: The widespread use of electromagnetic waves in communication has led to the consideration of their biological effects. According to valid scientific findings, these waves can entail changes in the cell function, there by causing or accelerating some diseases.OBJECTIVES: Since the amount of liver enzymes in the blood can be a sign of liver damage, this study was performed to evaluate these enzymes.METHODS: This experiment was done on 120 six-month-old pigeons. After adaptation to laboratory settings, they were divided into six random groups of distance from BTS and daily exposure time. G1: 50 cm/30 minutes, G2:100 cm/30 minutes, G3: 150 cm/30 minutes, G4: 50 cm/60 minutes, G5:100 cm/60 minutes, and G6:150 cm/60 minutes.Each group was exposed to waves for one month daily and blood tests were measured to determine the amount of liver enzymes before and one month after exposure; the results were processed by SPSS software.RESULTS: The findings of this study revealed a statistically significant relationship between BTS waves and liver damage after the increase in the level of liver enzymes in all six groups. Therefore, it is safe to assume that electromagnetic waves, depending on the frequency, energy, duration and distance, can have destructive effects on body tissues, including the liver. The mean changes of ALP and ALT were the highest and the lowest, respectively. Also, the most changes in liver enzymes occurred in the first and fourth groups, which had the shortest distance to the wave source.CONCLUSIONS: Increasing the exposure time and reducing the distance to the wave source changed the amount of liver enzymes. This study showed that "distance to the source of wave propagation" was more important than "exposure time".

BACKGROUND: Nucleotides (NT) are known as semi- or conditionally essential nutrients which might occasionally become essential in pathological and stress conditions that demand intense nucleic acid and protein synthesis.OBJECTIVES: A feeding trial was conducted to evaluate the effects of NT supplementation on growth performance and stress resistance of fry kutum (Rutilus kutum).METHODS: A basal diet was supplemented with 0 (control), 0.3, 0.5, and 0.7 g NT kg-1 to formulate four experimental diets. After eight weeks of feeding trial, the growth parameters were evaluated and then fish exposed to osmotic stress. To elucidate the underlying physiological mechanisms, cortisol and HSP70 levels were measured at selected times of 0, 2h, 8h, and 24h after the osmotic shock.RESULTS: According to the results of growth parameters after eight weeks of feeding trial, fish fed diet with 0.7 g NT kg-1 had the highest final weight and DGR compared with the other treatments (P<0.05). However, no significant differences were observed concerning FCR, SGR, CF, and PER between the treatments (P>0.05). The results of HSP70 revealed that fish fed with NT had higher levels of HSP70 expression. Additionally, the levels of HSP70 at 2h increased significantly by 3-7-folds over the baseline levels (0h), and then decreased significantly at 24h; however, HSP70 levels at 24h was 1-3-fold over the baseline levels. The findings of cortisol showed that Cortisol values were significantly affected by dietary NT levels (P<0.05) and lower stress-induced cortisol and glucose elevation were observed in all the NT groups compared to the control group. Moreover, plasma cortisol levels reached a significant peak 2h after the salinity stress. This value decreased significantly after 8h, returning to the pre-stress levels by 24h (P>0.05).CONCLUSIONS: Our data indicated that NT administration promoted growth performance and increased the ability of resistance to osmotic stress during freshwater to seawater transfer in fry kutum.

BACKGROUND: Reducing the protein and amino acid content of diet or altering the dietary electrolyte balance were suggested as the effective strategies to prevent the harmful effects of the heat stress in poultry.OBJECTIVES: This study surveyed the effects of various levels of threonine and dietary cation-anion balance on the broiler chickens under the heat stress conditions.METHODS: 700 one-day-old male broilers (Ross 308) were used for 6 weeks under high- temperature conditions. This experiment was conducted using a 2 × 3 + 1 factorial experiment based on a completely randomized design, with 7 treatments (5 replicates per treatment and 20 birds per replicate). Experimental factors included two threonine concentrations (recommended level and 10 % above recommended level) and three dietary electrolyte balances (175, 250, and 325 mEq/kg). The control group considered the treatment with a normal threonine concentration (recommended level) and a dietary electrolyte balance of 250 mEq/kg under optimal temperature conditions.RESULTS: Although there was no interaction between threonine level and electrolyte balance, the electrolyte balance of 175 meq/kg increased the performance index compared to the electrolyte balance of 250 or 325 mEq/kg (P<0.05). The villus height to crypt depth ratio and villus surface area in the jejunum improved with an electrolyte balance of 175 or 250 mEq/kg (P<0.05). A decrease in the dietary electrolyte balance increased in the nitrogen-corrected apparent metabolizable energy (P<0.05). Besides, an increase in the population of lactobacilli and bifidobacteria in the cecum, as well as an increase in protein digestibility, were observed by increasing levels of threonine in the diet (P<0.05).CONCLUSIONS: Based on these results, a high level of threonine or a low electrolyte balance in diet (175 mEq/kg) may improve the performance, metabolizable energy, and intestinal microbial flora of broilers reared under heat stress.

BACKGROUND: Stocking density is one of the most important problems in the poultry industry, which impair their production and welfare.OBJECTIVES: This experiment was done to evaluate the effect of organic selenium supplementation on the growth performance, blood metabolites, and the meat quality of broiler chickens in different stocking densities.METHODS: 216 one-day-old male broiler chickens (Ross 308) were used in 2×2 factorial arrangements by 2 stocking densities (7 and 15 birds/m2) and 2 levels of selenomethionine (0 and 0.4 mg/kg) in a completely randomized design with 4 treatments and 4 replicates.RESULTS: The feed intake (FI), and body weight gain (BWG) were significantly affected by the stocking density and selenomethionine (SE-MET) supplementation in the overall experiment (P<0.05). FI and BWG decreased and feed conversion ratio decreased in 15 bird’s density, while SE-MET inclusion improved these traits (P<0.05). Increasing stocking density increased the plasma glucose (P<0.05). Blood glutathione peroxidase and lymphocyte levels reduced at 15 bird’s density, while increased by 0.4 mg SE-MET supplementation (P<0.05). Increasing stocking density increased blood heterophil, while SE-MET inclusion decreased it (P<0.05). Meat pH and cooking loss were not affected by stocking density. Dripping loss (DL) increased, and water holding capacity (WHC) decreased at 15 bird’s density, but 0.4 mg SE-MET decreased DL and significantly increased WHC (P<0.05).CONCLUSIONS: It was concluded that increasing stocking density had the negative effects on the growth performance and meat quality of broiler chickens; however, the supplementation of 0.4 mg of SE-MET to diet can improve the growth performance, blood metabolites and meat quality of broiler chickens.

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.