مجله تحقیقات آزمایشگاهی دامپزشکی
سال چهاردهم شماره 1 (بهار و تابستان 1401)

Marek's disease (MD) is a highly contagious neoplastic disease in poultry. The causative virus is an alphaherpesvirus that causes immunosuppression and predisposes poultry to other pathogens.  Although the MD is more common in laying, the incidence of the disease is also increasing in broilers. Due to the increasing rate of infection with the marker virus in broiler chickens, this study aimed to investigate the occurrence of MD in broiler poultry farms in Semnan, Iran. The feather follicle epithelium and spleen tissues were collected randomly from 15 broilers flocks at 6-10 weeks old in Semnan slaughterhouse and were subjected to polymerase chain reaction by amplifying the meq gene. The results of this study showed of 15 flocks, two (13.6%) had a positive reaction. There was no evidence of macroscopic lesions among the studied flocks. Considering the infection of 13.6% of the studied flocks, without any macroscopic complications, it seems the MD virus is circulating in broilers and could transmit to the other birds. It is indicated that the current national vaccination has not stopped the disease in commercial chickens. Due to the immunosuppressive properties of the virus, it is considered that the MD virus, along with other immunosuppressive agents such as adenoviruses, has an essential role in the development of immunosuppression syndrome in broilers in Iran, and to reduce the economic losses caused by this disease, effective prophylactic measures should be considered by the country's health officials.

Distichiasis is an uncommon eyelid disease found in dogs and cats. This disease can result in corneal damage with various severity over time. The occurrence of this disease is congenital. This report concerns an 8-month-old Shih Tzu-terrier dog whit both eyelid distichiasis. This case was referred for eye pain, blepharospasm, and unsuccessful treatment in other veterinary clinics. After evaluation, conjunctival inflammation and distichiasis without corneal stromal ulcer have been found. For treatment, on day first, conjunctival inflammation and blepharospasm were cured, and on the second day, electro epilation was done. Re-examination in the following weeks showed a decrease in inflammation of the conjunctiva and the edge of the eyelid and a reduction in itching and blepharospasm in the animal. No other systemic drugs were used for treatment except anesthesia and serum therapy during anesthesia. After treatment, anti-inflammatory drops and antibiotics were used to reduce inflammation and prevent eyelid infections.

The Femoral head and neck osteotomy (FHO) limits the contact between the femoral head and the acetabulum, and with the formation of dense fibrous tissue, allows the formation of a fibrous pseudo-joint in place. Platelet-rich plasma (PRP) contains platelets, growth factors and cytokines, which are involved in reducing joint pain and faster recovery of skeletal-muscular tissue. The purpose of this study is to investigate the analgesic effects of platelet-rich plasma in femoral head and neck ostectomy in rabbits. In this study, 18 New Zealand white rabbits were studied in two groups (n=9). Blood (6 ml) was taken from the heart of each rabbit separately and poured into tubes containing sodium citrate anticoagulant. To prepare PRP, primary centrifugation was performed at 1600 rpm for 10 minutes and secondary centrifugation at 2000 rpm for 10 minutes, and then it was activated by adding CaCl2. After complete anesthesia, femoral head removal was performed. In treated and control groups, the surgical site filled with PRP and normal saline, respectively. Finally, the joint capsule, muscles and skin were sutured in a routine manner. The studied groups were examined for symptoms of pain and lameness using the Glasgow system. Based on the results, in the PRP treated group compared to the control group, pain was significantly reduced, and as a result, it can be stated that the use of PRP in orthopedic surgeries can reduce pain. It leads to faster use of the organ by the patient and helps the patient return to normal conditions.

Intussusception is one of the unusual diseases in dogs and cats. Any change in the movements of the intestines and the difference in the movements of different parts of the intestine can be a risk factor for its occurrence. Some drugs used to control symptoms and treat gastrointestinal diseases can cause changes in bowel movements. Ranitidine and metoclopramide are among these drugs that, in addition to their main properties, increase the movements of parts of the intestine. The following report is about a male cat that is treated for diarrhea and vomiting caused by a change in diet with listed drugs. After one week of using prescription drugs, the animal presents with symptoms of black diarrhea and severe lethargy state. The history indicated overdose of prescription drugs by the owner. despite maintenance treatments, this animal died after two hours of being in the hospital due to severe anemia and the lack of matching blood for transfusion. Autopsy showed the presence of intussusception.

Bisphenol A (BPA) is a chemical used in the manufacture and hardening of plastic products. Iran is one of the top 10 countries in the world in terms of consumption of plastic products, and as a result, the release of plastic waste turns into the release of substances such as BPA in water resources and in aquaculture systems. One of the ways to evaluate the presence of chemical factors in the environment of fish is to measure antioxidant defense indicators in fish tissues. This study investigated the antioxidant defense responses of rainbow trout exposed to BPA. The liver tissue of 110 pieces of rainbow trout (55 ± 0.4 grams) were sampled after 14 days of experimental fish exposure to zero, 10 and 50 micrograms per liter of BPA for antioxidant defense indicators assay such as catalase, superoxide dismutase, malon di-aldehyde and glutathione peroxidas. All indicators were significantly increased after exposure period of 14 days to 10 and 50µg/L of BPA (P˂0.05) which confirms the possibility of benefiting from these indicators in following the trace pollution with plastic products in the water and food sources of humans and the aquatic environment.

Salmonella typhimurium is one of the most pathogenic salmonellas that lead to infection in humans, livestock and poultry. Excessive use of antibiotics in order to reduce complications and destroy bacteria in different doses leads to the development of resistance. Therefore, the use of antimicrobial compounds without side effects is considered important.

The present study was conducted to investigate the antimicrobial effect of the combination of two extracts of Thymusvulgaris and Altheaofficinalis and the synergism of this substance with erythromycin on Salmonella typhimurium infection.Materials: For this purpose, 40-day-old chicks of Ras 308 breed were used in four groups. Experimental treatments included negative control, treatment with antibiotics, treatment with TymasinPlus syrup and treatment with antibiotic and TymasinPlus. After induction of infection, on days four and twelve, after death by pity, liver and spleen tissues were isolated and tested.

The results of colony counting proved that TymasinPlus syrup has an antimicrobial effect on Salmonella typhimurium bacteria. The highest number of bacteria was specific to the control group and the lowest amount was related to the group treated with antibiotics and TymasinPlus; It was also found that TymasinPlus commercial syrup has the same function as antibiotics and is effective in reducing the bacterial population synergistically with antibiotics.

It is better to use the herbal medicine TymasinPlus instead of using chemicals when the infection caused by Salmonella typhimurium occurs.

This research was carried out in order to investigate the use of cumin and black cumin powder mixture on performance, some biochemical parameters of serum and morphology of small intestine tissue in male Japanese quails. In this experiment, 160 pieces of Japanese male quail were used in a completely randomized balanced design with four treatments, four replications and 10 pieces of quail in each replication from the age of 7 to 35 days. The supplement of mixed green and black cumin powder was used at four levels of zero (control), 0.5, 1 and 1.5% in the diet. The results showed that the use of a mixture of cumin and black cumin powder had no statistically significant difference on the amount of feed consumption, weight gain and feed conversion ratio compared to the control treatment. Also, the weight of the carcass, breast, thigh, pre-stomach, gizzard, intestine and heart was not significantly affected by the treatments. The amount of blood serum cholesterol decreased significantly (P≤0.05). Serum glucose significantly increased in the treatment containing 0.5% of the mixture of green and black cumin powder (P≤0.05). Total protein significantly increased in the treatment of 1.5% green and black zebrafish mixture (P≤0.05). Serum triglyceride decreased significantly (P≤0.05) in treatments using black and green cumin powder (P≤0.05). The amount of serum uric acid in the diet with 1% mixed powder of green and black cumin was significantly (P≤0.05) higher than other treatments. There was no significant difference between the length, width, height of the villi and the mucous layer of the small intestine in the treatments using green and black cumin powder and the control treatment. In general, the results of this research showed that the use of cumin and black cumin powder in male Japanese quails is recommended.

In this study, 100 blood samples of tick-infested dogs in Isfahan were collected and examined for molecular detection by Nested polymerase chain reaction (Nested PCR) method. Seven blood samples were found to be infected with Anaplasma phagocytophilum and their results were positive. Hematological studies of positive samples were showed that, in one of them, severe anemia, low hematocrit and neutrophillia without leukocytosis was seen.In four of them, anemia and neutrophilia (in 2 of them had leukocytosis also) was seen. and in two other positive samples, only neutrophilia was seen. In morbidity of the Anaplasma phagocytophilum infection in tick infested dogs, our examination and stastical analysis of data reveals that, age and contamination of the environement were affected but the genus were not affected the incidense of the disease.This study were conducted in four seasons of one year and it was done by the first time in Esfahan,middle province of Iran.

Due to the growing interaction between humans and dogs, along with the potential transmission of urinary infections from pets to humans, and considering the insufficient resources available on bacteremia in dogs in Karaj, Iran, the present study aims to investigate the frequency of bacterial urinary tract infections in dogs experiencing urinary issues and explore associated risk factors. 
Methods and Materials: This quasi-experimental study was conducted on 86 dogs referred to the Baran Veterinary Clinic in Karaj city. Urine samples (10 cc) were collected via cystocentesis under sedation. Each sample was divided into two separate parts: one for complete urine analysis and the other for bacterial evaluation and urine culture.
In the study, 86% of the examined samples showed bacterial contamination. Among these, 40 samples were positive for E. coli, 18 for Enterococcus, 7 for Proteus, 5 for Klebsiella, and 4 for Staphylococcus. Breed (P=0.73) and gender (P=0.24) did not affect the incidence of bacterial infection, while the incidence of bacterial infection was higher in breeding dogs than in domestic dogs (P=0.03).
Escherichia coli and Enterococcus are the most common strains isolated in dogs with urinary tract infections. Given the high resistance of these bacteria to antibiotic treatment, it is recommended that future research focus on effective treatment and control strategies for these strains. Additionally, the present study revealed a very high frequency of bacterial infections in dogs with urinary problems, highlighting the need for proper follow-up of the health status of stray dogs in Karaj, Iran.

Background &  Lead is a toxic metal to living organisms, including humans. In recent years, the use of different types of nanoparticles such as nanochitin has become common for the removal of lead from aqueous solutions. This study aimed to evaluate the effect of nanochitin (1.6 mg/kg) on kidney tissue, the rate of Pb (50 mg/kg) absorption and elimination from kidney tissue. Materials &  Seven groups of 5 Wistar rats (180-150 g, 8-10 weeks) were fed with Pb and nano chitin with different doses and duration. After euthanasia, kidney tissues were separated and Pb concentration was measured by atomic absorption spectrometry. Kidney tissues were also prepared for hematoxylin-eosin staining and then were examined by light microscopy. No tissue damage was observed in nano chitin-fed rats. The use of nano chitin significantly reduced the Pb concentration as well as lesions in the tissues of all groups that were fed with nanochitin and Pb compared to the group which was fed only with Pb. Nanochitin consumption after two weeks reduced Pb concentration in the tissues of all rats fed with Pb for 4 weeks compared to the control group.  The results of this study showed that nano chitin, without having negative effects on kidney tissues, can cause the reduction of the Pb absorption and its removal from the body. Therefore, it seems that this substance can be used as a dietary supplement to prevent Pb poisoning.