BACKGROUND: Today, due to the high cost of animal proteins on aquatic diets, a great deal of attention has been paid to further use of plant proteins.OBJECTIVES: The present study aimed to replace fish meal with corn protein concentrate (CPC) (Empyreal® 75) and investigate its effect on growth, survival, and body composition of Siberian sturgeon (Acipenser baerii).METHODS: Corn protein concentrate was replaced with fish meal at four levels of 0, 15, 30, and 45 % in three replicates in a completely randomized design. A total of 120 Siberian sturgeons weighing 8.27±0.39 g were distributed into twelve 80-L round plastic tanks with a density of 10 fish per tank. After a week of acclimatization period, fingerlings were fed with four diets with the same protein and energy levels (isonitrogenic and isocaloric) for 60 days. At the end of the experiment, growth parameters and carcass composition were measured.RESULTS: The results revealed that the total length, final weight, body weight increase. Specific growth rate, average daily growth, protein efficiency ratio, and condition factor were significantly higher in fish fed with corn protein concentrate at the level of 15 % compared to the other treatments (P<0.05). The food conversion ratio had the lowest value in this treatment, which showed a significant difference with the other treatments (P<0.05). A significant difference in carcass protein was observed in fish fed corn protein concentrate 15 % and 30 % in comparison with fish fed with 45 % corn protein concentrate. The survival rate was 100 % in all the treatments.CONCLUSIONS: Based on the obtained findings, it could be stated that corn protein concentrate at the level of 15 % can be a good substitute for fish meal in Siberian sturgeon diet.

BACKGROUND: Gallibacterium anatis is a recently defined genus, which is a member of the Pasteurellaceae family. This advantageous pathogen is frequently found as part of the normal microflora of the upper respiratory tract and lower genital tract of the healthy poultry. Provided with appropriate conditions, it leads to various diseases, such as salpingitis, peritonitis, and loss of egg production with mortality in layer flocks. According to previous studies, multiple antibiotic resistance has been observed among G. anatis isolates, which can impose high costs on layer flocks. Due to the lack of the pathognomonic symptoms in the conflicts caused by this bacterium,  not enough comprehensive research has been conducted to date on the condition of this disease in Iran.OBJECTIVES: This study aimed to investigate the infection rates of this bacterium via PCR.METHODS: 295 tracheal swabs were collected from 10-layer flocks. Subsequently, the suspected colonies were isolated and identified with morphological features, differential cultivation, and PCR.RESULTS: 43.72 % of the samples were positive.CONCLUSIONS: The results of this study indicated that laying farms in Iran were infected with Gallibacterium anatis; thus, certain measures should be taken to control the factors reducing the production of layer flocks.

BACKGROUND: Corynebacterium pseudotuberculosis and Trueperella pyogenes are two important pyogenic bacteria that cause many annual economic losses worldwide. Currently, antibiotic resistance of these bacteria is on the rise. Early detection of infection with these bacteria is important for controlling the infections caused by these two bacteria.OBJECTIVES: This study aimed to investigate the contamination of cattle cutaneous abscesses with  Corynebacterium pseudotuberculosis and Trueperella pyogenes in five large cattle farms around Tehran and propose an accurate method for a rapid detection of these two bacteria.METHODS: Out of 60 cows involved in cutaneous abscesses in the summer of 2018, sterile sampling was performed to diagnose the bacterial agent that caused the abscess. Bacteriological examination of the samples was performed using standard biochemical reactions and polymerase chain reaction using specific primers.RESULTS: Of the 60 samples studied, 25 % (15.60) were isolated as Corynebacterium pseudotuberculosis and 20 % (12.60) as Trueperella pyogenes. In 55 % of the samples (33.60), both bacteria were present simultaneously. All the samples detected using biochemical reactions were confirmed by the polymerase chain reaction.CONCLUSIONS: Corynebacterium pseudotuberculosis and Trueperella pyogenes are the main causes of cutaneous abscess in cattle farms around Tehran. Because the accurate diagnosis of the cause of abscesses is very important for effective treatment, polymerase chain reaction, based on 16S-23S rDNA and 16S rRNA, can be used to rapidly and accurately detect these bacteria in the early stages of the infection.

BACKGROUND: Impingement of the dorsal spinous processes is a common cause of pain and poor performance in sport horses.OBJECTIVES: This study was performed to evaluate the prevalence of impingement in dorsal spinous processes and the correlation between the occurrence of this complication and certain parameters, such as age, height, weight, discipline, breed, neck length, and clinical signs.METHODS: In this study, radiographic examination of the spine of 50 horses were performed. The information about height, weight, discipline, breed, neck length, and clinical signs were also collected. Radiographic grading was based on the degree of the changes in inter spinous spaces and their densities (0-4 degrees). The clinical examinations were carried out to evaluate the pain in the spine. Statistical analysis was performed to investigate the correlation between the collected data.RESULTS: The highest incidence of impingement was seen in the middle thoracic area. There was a significant correlation between the occurrence of impingement and age and the breed of the studied horses. There was no correlation between the incidence of impingement and sex, height, neck length, and weight of the studied horses.  Increased radiographic grade often leads to an increase in the severity of clinical signs. A higher grade of radiographic sign in each horse was indicative of more involved inter spinous spaces.CONCLUSIONS: According to the results of this study, Grade 3 and 4 had high specificity with clinical signs; therefore, preparation of a radiograph of the spine before purchasing a horse could be highly recommended.

BACKGROUND: Microencapsulation of probiotic bacteria is an area that has rapidly expanded over the recent years. It is one of the new methods of improving probiotics stability, through which the biological agents are protected with an enclosed coating to release the active agents within the coating at a controlled rate in time and under special conditions.OBJECTIVES: The present study the aims to evaluate the effect of Lactobacillus plantarum microencapsulation with chitosan/alginate microparticles on the oxidative response of Nile tilapia fish (Oreochromis niloticus).METHODS: Herein, 240 pieces of Nile tilapia, with an average weight of 15.56±0.02 g, were randomly divided into four groups as follows: group1 or control with a diet without probiotics, groups 2, 3, and 4 respectively with a diet containing 108 Log CFU/g of unencapsulated Lactobacillus plantarum, a diet containing microencapsulated Lactobacillus plantarum, and with feed containing alginate with chitosan without the presence of bacteria. They were fed for 60 days at the rate of 2 % of body weight twice a day.RESULTS: The activity level of oxidative enzymes, biochemical factors, and liver enzymes of the Nile tilapia fish were investigated. The findings revealed that oxidative enzymes, biochemical factors, and liver enzymes were positively affected in the groups with microencapsulated Lactobacillus plantarum (P<0.05). The three enzymes of alanine transaminase, aspartate transaminase, and alkaline phosphatase were higher in the micro-encapsulated probiotic group compared to the two groups of probiotics and alginate with chitosan without the presence of bacteria, and all the three groups performed better compared to the control (P<0.05).CONCLUSIONS: Microencapsulation of probiotics maximizes the efficiency of probiotics in reducing oxidative stress.

BACKGROUND: There is growing evidence that resistance to antibiotics is increasing, and because of their wide range of negative impacts on the environment and humans, also accumulative effects in fish meat and hazards for humans, there have been numerous studies conducted using medicinal plants as a healthier alternative to antibiotics.OBJECTIVES: This study examined the antibacterial effect of two native medicinal herbs (oregano and echinacea mixed essential oil) on Lactococcus garvieae compared with some commercial antibiotics used in fish farms.METHODS: The antibacterial activities against a fish bacterial pathogen (Lactococcus garvieae) were tested using the disk diffusion method, followed by the determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations via sequential dilution of essential oil by Broth Micro Dilution method.RESULTS: The results showed antimicrobial activities of mentioned mixed essential oil with MIC ≥ 6.25 μL/mL and MBC ≥ 12.5 μL/mL. Also, the measurements of the diameter of inhibitory zones are consistent with the results of MIC and MBC, indicating the positive effect of this plant mix oil Lactococcus garvieae. However, the Lactococcus garvieae was more sensitive to Enrofloxacin (NFX 5), and Sulfamethoxazole &amp; Trimethoprim (SXT) (P<0.05), but the combination of Oregano and Echinacea essential oils performed better than Florfenicol (FF) despite the weaker effects against mentioned two antibiotics.CONCLUSIONS: The results approved the antibacterial activity of the mixed essential oil of oregano and Echinacea against Lactococcus garvieae on the laboratory scale. Using these compounds as a possible substitute for antibiotic compounds requires more clinical studies.

BACKGROUND: Bovine Herpes Virus-1 (BHV-1) belongs to the  Alpha herpesviral family. The virus is the cause of Infectious Bovine Rhinotracheitis (IBR) and Bovine Abortion. In the initial infection, the virus proliferates excessively. Moreover, shedding the virus leads to conditions in the latent phase of the disease. Infectious Bovine Vulvovaginit (IPV ) is the genital form of the disease that represents a genital infection and transmits via pustules and mucopurulent secretions. Exposure to the virus in genital mucosa leads to IPV infection through mating or artificial insemination and the diseases that can be transmitted to healthy livestock by frozen sperm during artificial insemination.OBJECTIVES: Viral contamination of the semen is one of the routes to spread the disease among dairy cattle. Therefore, we investigated the presence of the virus in domestic and frozen imported semen consumed in industrial dairy cattle farms.METHODS: In the present study, 140 frozen straws were collected. After melting each straw, 200 µl of obtained semen was used for DNA extraction, which was done directly on the semen samples and via a Genome Extraction Kit. Subsequently, to ensure the accuracy of the extraction, the PCR technique was done using PRM-1 gene primer. Tracking the viral genome was done using the PCR technique and known primers.RESULTS: In total, one out of 140 samples was found to be virally contaminated, and IBR contamination was confirmed by repeating all the steps and determining the gene sequence.CONCLUSIONS: It is necessary to further investigate the possibility that contamination can be transmitted via frozen semen, given that even one out of 140 samples is contaminated, and the importance of the disease.

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.