مجله تحقیقات دامپزشکی
سال هفتاد و ششم شماره 1 (بهار 1400)

Over the recent years, Neospora caninum has been one of the most important causes of abortion in dairy cattle.

We conducted the present study in order to investigate the seroprevalence of N. caninum in dairy cattle in Semnan province and its effect on abortion.

237 blood samples were obtained from various Semnan dairy farms and 104 bulk dairy samples from four milk collection centers in Semnan, Garmsar, Damghan, and Shahrood were tested for sera and milk utilizing ELISA (Svanova Biotech AB) test kits.

The results revealed that 87.27 % of bovine serum was positive. The percentage of opacity density (OD) of positive sample (PP) ranged from 72.17 to 137.3 (114.21±24.65). In addition, the average rate of milk seroprevalence to the parasite was 95.23 % in Semnan province.

The frequency of Neospora caninum infection in blood and milk was high in Semnan, yet no significant relationships were observed with abortion (p < /em>>0.05).

Trypanosomosis is a blood parasitic disease with veterinary and cosmopolitan importance due to Trypanosoma evansi (Kinetoplastida: Trypanosomatidae) type A in camels, cattle, buffaloes, and equine and type B in camels.

We conducted the present study to discriminate Trypanosoma evansi type A and B infection in one-humped camels (Camelus dromedarius) in Sistan-va-Baluchestan Province, south eastern Iran.

A total number of 369 blood samples were randomly taken from jugular vein of the examined one-humped camels from different parts of the region. Genomic DNA was extracted and polymerase chain reaction (PCR) was performed to amplify 205bp-fragment-length and 436bp-fragment-length of RoTat 1.2 VSG gene (T. evansi type A) and Minicircle gene (T. evansi type B), respectively.

Molecular findings revealed that all the infected camels were affected by T. evansi type A.

Based on the results of the current study, we could conclude that the cause of infection in the examined camels of the region, like other parts of the world, was T. evansi type A.

The defects of the central nervous system caused by viruses are associated with tissue changes in certain areas of this system.

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.

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.

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.

It seemed as though in each of the four pathological patterns, certain viral agents were responsible for the pathological changes.

Intensive aquaculture and commercialization production are believed to be needed for improving fish health status and probiotics are candidates to achieve this goal.

In this study, we utilized Lactobacillus plantarum and Lactobacillus pentosus as autochthonous food supplementation for biochemical investigation in rainbow trout.

In the current study, 240 juvenile rainbow trout with an average weight of 15 ± 2 g were randomly divided into four groups with three replications. Group 1, 2, and 3 were fed with 108 CFU/g of L. plantarum, L. pentosus, and the combination of these two probiotics, respectively. The control group was fed with the normal diet, for 60 days (2 % of body weight, 3times per day). Samples were taken at days 0 and 60 and biochemical parameters and hepatic enzymes activity were then investigated.

Most biochemical factors had positive changes in the fish fed with probiotics, particularly in L. plantarum group (p < 0.05). Furthermore, the results exhibited a significant decrease in ALP level in the probiotic groups, particularly in L. pentosus group (p < 0.05). Meanwhile, AST enzyme activity in plantarum+pentosus group was higher than that in the other groups (p < 0.05).

The present results indicated the effectiveness of food supplementation with probiotics in fish diet with the preference of probiotic to improve the biochemical factors and hepatic enzymes activity of rainbow trout, Oncorhynchus mykiss.

The use of additives, such as medicinal plants, may result in improved digestion and fermentation and consequently, animal production.

The present experiment was conducted to determine the most appropriate amount of Ziziphora cliniopodiodes plant to be utilized in lamb diet and its effect on digestibility, fermentation, growth performance, blood, and quality of carcass and meat.

Different amounts of Ziziphora cliniopodiodes (0, 0.2, 0.4, 0.6, 0.8, 1 %) were added to diet of lambs. The best diet was selected based on gas production method and fed to male lambs with an average weight of 41 ± 2 kg in a completely randomized design with three treatments and six replications. The selected diets for feeding lambs included: control diet (Ziziphora cliniopodiodes) and control diet supplemented with 0.2 or 0.4 % Ziziphora cliniopodiodes. Feed intake, digestibility of nutrients, fattening performance, blood and rumen fermentation parameters, protozoan population, and certain meat quality indexes were measured. At the end of the experiment, the carcass traits were studied.

The obtained results herein revealed that the potential of gas production, partitioning factor, truly degradable organic matter, dry matter intake, apparent digestibility of dry matter, organic matter, crude protein, neutral detergent fiber, acid detergent fiber, glucose, cholesterol, triglyceride, blood urea nitrogen, and protozoa population were not affected by the experimental diets. There was a significant difference among the experimental diets for daily weight gain, the total weight gain of lambs, and microbial biomass production. The highest records belonged to the diet containing 0.2 % Ziziphora cliniopodiodes. Antioxidant characteristics, colorimetric indices, and pH of meat were not affected by the applied treatments.

In general, according to livestock experiments, the best amount of Ziziphora cliniopodiodes to be employed was 0.2 %, which improved certain fermentative and performance traits.

Yersiniosis is known as one of the most prevalent bacterial diseases in fish, which causes high mortality and economic losses in cultured fish farms every year.

The present study was conducted to investigate the changes in hematological indices and gut histopathology in Caspian roach (Rutilus caspicus) exposed to Yersinia ruckeri.

60 Caspian roach broodstock with an average weight of 63.4 ± 2.1 g were divided into three groups (with two replicates for each group), including one treatment, one positive control, and one negative control groups. The treatment group was intraperitoneally injected with Yersinia ruckeri bacterium at a dosage of 3.8 × 107 cell/fish. The positive group just received normal saline (0.9 % NaCl) via intraperitoneal injection. No injection was performed in the negative control group.

Symptoms appeared on the fourth day after exposure and 20 % of the fish in the treatment group died 5 days after the challenge. Cumulative mortality reached 53 % on day 9 after the challenge.  According to hematological analysis, the challenge with Yersinia ruckeri led to a significant increase in white blood cell counts (WBC) compared to the control groups. Moreover, 10 days following exposure, the treatment group experienced hypochromic macrocytic anemia. Gut histopathology was characterized with necrosis and detachment of intestinal epithelial cell and inflammatory cells infiltration in the treatment group.

Based on the obtained results herein, Yersinia rackeri can cause acute disease in Caspian roach; therefore, preventing and controlling this disease is essential for these fish in infected regions.

Calf pneumonia is one of the most common diseases in dairy and beef herds.

To compare steroidal and non-steroidal anti-inflammatory drugs as adjunctive therapy in dairy calf pneumonia.

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.

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).

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.

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.

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.

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).

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.

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.

Backyard poultry are at risk of exposure to various viral contagious diseases such as Newcastle (ND) and Avian Influenza (AI). These diseases, in addition to the backyard poultry infection have an influence on villagers’ livelihoods. Also, backyard poultry plays an important role in circulation and survival of these viruses in environment and are considered as a risk factor for the poultry industry.

Studying the prevalence level of ND and Influenza H9N2 diseases in backyard chickens in Iran, in 2014-2015.

A descriptive cross-sectional study was conducted for two years (2014-2015) in backyard chickens with mortalities suspected of infection with ND or AI H9N2 viruses. Each mortality report was considered as one outbreak. For detection of possible ND or influenza virus infection tracheal and lung tissue samples were investigated by RT-PCR reaction test. Results were analyzed statistically by SPSS software.

Overall, 121 outbreaks of Newcastle or influenza (H9N2) disease with 25.936 cases of death from 17 provinces were reported in two years. of  these, 54 outbreaks (44/6 %) were caused by H9N2 influenza virus, 58 (47/9 %) by velogenic ND virus and 9 (7/4 %) outbreaks were caused by influenza and Newcastle concurrent infection. Hotspot ratio in 2015 was significantly higher than in 2014. In comparison with Newcastle disease alone or concurrent ND and influenza outbreaks, the highest mean mortality rate was observed in H9N2 outbreaks. Outbreaks were reported in all seasons but the rate of occurrence in the months of June and July was significantly higher than the rest of the year.

According to our results ND and H9N2 influenza virus infections are widely distributed in backyard chickens of villages in Iran. So, for implementation of control strategies, education of villagers, vaccination and annual surveillance of backyard poultry seem necessary.

There have been many reports on spinal cord injuries in humans and animals, which is  a major medical and veterinary concern; therefore, the present research project was carried out to devise an appropriate treatment approach.

The purpose of the present study was to apply the modified Allen’s test and Royan Impactor Devicein order to 1) induce spinal cord injury on rhesus monkeys and 2) gain the ultimate confirmation by clinical examinations and MR imaging for application in human and veterinary medicine.

Royan Impactor Device  was used to induce spinal cord injury on rhesus monkeys. Five rhesus monkeys were anesthetized with ketamine, xylazine, and isoflurane. Laminectomy  was done at the level of T9-T10, and a 50 g weight was then dropped from a 12 cm height through a guide tube onto a 10 mm2 impact plate on the exposed spinal cord.

The results of the present study showed signal changes with decreasing the trend in the T2W of spinal cord in sagittal and axial areas due to hematoma, inflammation, pressure on spinal cord, and tissue destruction after spinal cord injury. In the clinical examination of all samples, spinal cord shock symptoms, marked by bladder distention, disappeared 3-5 days post spinal cord injury. Not all measurable factors related to the severity of the injury  were restored to the normal condition until the end of the study although their severities were reduced to some extend.

Modified Allen’s test and the instrument that we designed for this study were able to satisfy the needs of the researchers in treating the spinal cord injury.

Plasma lipoprotein profile is one of the effective mechanisms in testicular tissue development and spermatogenesis process in roosters.

The present study was conducted to investigate the effect of dietary supplementation of l-carnitine during pre-pubertal period on testicular histology, spermatogenesis indexes and plasma lipoproteins of immature cockerels

A total of twelve Ross broiler breeder males (12 weeks) for 22 weeks in a completely randomized design with two treatments (0, and 250 mg/kg of L-carnitine in the diet) and six replications were used. Feeding program, and photoperiod regimen was performed based on ROSS 308 management handbook. To achieve the objectives of the study, at the age of 34 weeks, four birds were randomly selected from each treatment and after collecting blood samples from the veins under the wings, the birds were slaughtered. Finally, plasma cholesterol, LDL and HDL concentrations using a commercial kit and testicular parameters (number of seminiferous tubules, number of Sertoli cells, height of epithelium seminiferous tubules, seminiferous tubules diameter, spermatogenesis index, and tubular differentiation index) after preparation of 5-μm paraffin sections, were analyzed by SAS software.

The results showed that the number of seminiferous tubules, and the number of Sertoli cells were significantly affected by l-carnitine (p < /em><0.05). L-carnitine supplementation in the diet of immature cockerels before sexual maturity significantly increased the spermatogenesis index (p < /em><0.003) and tubular differentiation index (p < /em><0.02). HDL levels were significantly affected by l-carnitine supplementation (p < /em><0.007). There was a significant tendency in LDL concentration (p < /em>=0.09) and LDL/HDL ratio (p < /em>=0.059) between treatments, but no significant differences were observed in cholesterol concentration between treatments.

According to the results of this study, feeding immature cockerels before sexual maturity with 250 mg l-carnitine improves testicular tissue development and spermatogenesis process.

It is possible for Sex reversal of eggs with female embryo using anti-aromatase agents, and the hatchlings have an improved performance.

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.

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.

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).

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.

Due to the numerous biological effects of nanoparticles, nanotechnology can play a major role in future research areas in the poultry industry.

The SNP have antibacterial, antiviral and antifungal properties that are increasingly used in poultry farms. Therefore, the aim of this study was to investigate the effect of SNP on carcass and laying performance, qualitative and quantitative characteristics of eggs, fertility and hatchability in Japanese quail.

96 quails including 24 male quails and 72 female quails were assigned to 4 experimental groups with 6 replications in a completely randomized design. The experimental groups consisted of 0 (control), 4, 8, and 12 ppm SNP, which were given to the birds in drinking water. Quantitative and qualitative parameters of eggs and determining the percentage of fertility and hatching were performed on a weekly basis. Also, at the end of the experiment, body weight and relative weight of internal organs were measured.

The relative weight of liver and kidney organs increased in the SNP-receiving groups as compared to control (p < 0.05). There was a significant decrease in egg weight in SNP- receiving groups compared with the control group (p < 0.05). The effect of experimental groups on relative yolk weight was not significant. Albumin weight and yolk to albumin ratio increased in two groups of control and 8 ppm SNP, respectively (p < 0.05). Egg thickness and shape index decreased in groups 4, 8, and 12 ppm SNP as compared to control (p < 0.05). However, the effect of different experimental groups on quantitative and qualitative parameters of eggs including eggshell weight, eggshell membrane, and egg volume was not statistically significant. The SNP-receiving groups caused a dramatic increase in fertility rate as compared to control (p < 0.05); furthermore, the increase in hatchability rate in SNP groups was not significant (P>0.05).

The results of the present study showed that the use of 4 and 8 ppm SNP can improve the laying performance, fertility and hatchability rates in Japanese quail.

Bovine tuberculosis caused by Mycobacterium bovis is an important disease that has negative effects on public health and entails economic loss. Traditional controlling programs for cattle  focus on test and slaughter strategy, and false positive is one of the disadvantages associated with tuberculin skin test. To overcome this limitation, proteins with high specificity have to be utilized.

The objective of this study was to clone and express virulent protein CFP-10 from Mycobacterium bovis AN5.

Full-length genes of cfp-10 were amplified by PCR technique. In parallel, pET23a(+) and PCR products were double digested by EcoRI and HindIII. Ligation was performed at 16˚C followed by transformation into competence E. coli DH5α. After being identified with sequencing, the cloned vector was transformed into E. coli BL21. Induction was performed by isopropyl-β-D-thiogalactopyranoside (IPTG). Urea 8M was used to dissolve the expressed protein in the inclusion body form. Recombinant protein was purified by Nickle-Resin, and urea was eliminated by decreasing the gradient.

The CFP-10 gene clone was proved by sequencing method. The CFP-10, as a 10 KDa protein, was confirmed by Western blotting using monoclonal antibodies. Based on the results, the recombinant protein was successfully cloned and expressed.

The results showed that cfp-10 gene was successfully cloned and expressed in prokaryotic system, indicating that this recombinant protein could be utilized in diagnostic kits against bovine tuberculosis in the future.

Despite the availability of effective conjugate vaccines, Haemophilus influenza (HI) and Haemophilus somnus (HS) still result in enormous global morbidity in both human and cattle. Vaccines failure to protect against different strains can lead to the spread of Hemophilus infections. The absence of various epitopes from Haemophilus strains in existing vaccines is one of their weaknesses. Therefore, selection of a conserved and common set of proteins in the invasive strains of HI and HS is essential for predicting epitopes as potential vaccine candidate.

The aim of this study was to design an effective polyepitopic vaccine against invasive HI and HS strains using in silico approaches.

First, the protein sequences were retrieved from the databases and were aligned to determine the conserved areas with the Clustal omega software. Then, B and T cell epitopes identification was done for OapA, OMP6, PD, D15, IgA1 Protease and TbpA proteins using various immunoinformatic servers. The high ranked epitopes were selected from mentioned proteins. The selected epitopes were fused together by appropriate linkers. This designed construct was analyzed for physicochemical and structural characteristics using related servers.

6 TCD4+ and 3 B cell epitopes were selected to design the final construct from 6 common proteins. The immunoinformatics analysis revealed that the designed polyepitopic peptide is a safe, soluble, hydrophilic and thermostable antigen that could be a potential vaccine.

The polyepitopic construct can be considered as a vaccine candidate against Haemophilus.