BACKGROUND: Today, the fight against the bacteria causing foodborne diseases is of particular importance in the packaging of seafood. It is therefore vital to find new compounds with antibacterial properties.OBJECTIVES: In the present study, antibacterial properties of synthetic nanocomposite zinc chromite-zinc aluminate (ZnCr2O4-ZnAl2O4) on E. coli and Pseudomonas aeruginosa were studied.METHODS: After synthesis of nanocomposite, antibacterial activity of nanocomposite zinc chromite-zinc aluminate was evaluated via disk diffusion method, Minimum Inhibition Concentration (MIC), and Minimum Bactericidal Concentration (MBC) using the microdilution method.RESULTS: The results of this study revealed a higher sensitivity reaction of Pseudomonas aeruginosa (18.6±1.2 mm) compared to E. coli (12.7 ± 1.4 mm). No significant differences were observed between Gentamicin antibiotic and synthetic nanocomposite against Pseudomonas aeruginosa (P<0.05). The minimum MIC and MBC concentrations were seen in Pseudomonas aeruginosa (1.66 mg/ml) and the maximum concentration of MIC belonged to E. coli (5 mg/ml).CONCLUSIONS: In this study, the effects of nanoparticles on these gram-negative bacteria could be attributed to the small diameter of the ions, and hence the greater penetrability of these nanoparticles despite the wall's resistance. Based on the results, zinc chromite-zinc aluminate nanocomposite showed a better performance compared with gram-negative bacteria, specifically Pseudomonas aeruginosa resistant bacteria, and could be used for further studies in fisheries product packaging.

BACKGROUND: Fresh sausages are classified as one of the most perishable meat products due to the lack of using chemical preservatives.OBJECTIVES: The present study aimed to increase the refrigeration time of fresh sausages using Zataria multiflora Boiss. essential oil.METHODS: In this study, samples of fresh sausages, containing different concentrations of Zataria multiflora Boiss. essential oil (0, 0.05, 0.1, and 0.2 %), were prepared and stored under the refrigerated condition for 17 days. Subsequently, they were evaluated for microbial, chemical, and sensory properties at six time intervals (days 0, 2, 4, 6, 10, and 17).RESULTS: Based on the results of the study, by adding Zataria multiflora Boiss. essential oil to fresh sausages, the microbial count in the treatments containing high concentrations of essential oil (0.1 and 0.2 %) was significantly different from that in the control group (P<0.05). The amount of volatile nitrogen bases at the beginning of the study was 14 mg/ 100 g and after six days, in the control group, it reached 32.1 mg/ 100 g. Meanwhile, in the treated samples, it was less than 25 mg/ 100 g up to day 10. Moreover, at the end of the study, the level of TBARS in the control group reached 1.48 mg malondialdehyde /kg while this level was less than 0.78 mg malondialdehyde / kg for the groups treated with Zataria multiflora Boiss. essential oil. The results of this study also showed that the addition of essential oil has a non-significant effect (P>0.05) on sensory properties.CONCLUSIONS: Zataria multiflora Boiss. essential oil was found to have the potential to increase the shelf life of fresh sausages without adverse sensory effects.

BACKGROUND: Leucine is one of the subgroups of amino acids, which play an important role in the anabolism of muscles, adipose tissue, and the liver by stimulating insulin secretion.OBJECTIVES: Effects of different levels of leucine were investigated on carcass yield, characteristics, and quality, and expression of insulin-like growth factor (IGF-1) and insulin genes in male broilers.METHODS: Five levels of L-leucine (100, 110, 120, 130, and 140 % of Ross strain requirements) were tested with 250 male one-day-old chicks in a completely randomized design with five treatments and five replicates (containing 10 chicks each). On day 42 of their age, the blood samples of two birds from each replicate (10 birds per treatment) were taken to determine serum IGF-1 gene expression. Subsequently, these birds were slaughtered for analysis of carcass characteristics and quality, and collecting the samples of liver and breast for expression of IGF-1 and insulin genes.RESULTS: Body weight increased by consumption of 140 % of leucine as compared to 100 %. Reduction in feed conversion ratio was observed by feeding 140 % of leucine level. The IGF-1 gene expression of breast and liver increased by 110 % of leucine level. Moreover, feeding 110 % of leucine level caused a higher expression of insulin gene in breast and liver. Consumption of 130 % of leucine improved the meat protein, fat, and ash contents. Furthermore, consumption of 110 % of leucine increased the serum IGF-1 concentration.CONCLUSIONS: Consumption of leucine in broiler diets was found to increase the expression of IGF-1 and insulin genes and consequently, improve the performance and carcass quality. It also decreased the abdominal fat in broiler chickens.

BACKGROUND: The veterinary Rabies vaccine was produced using BHK-21 cells and PV strain. Although various protocols have been suggested for virus purification, they have an adverse effect on the final production and require further optimization.OBJECTIVES: The present study aimed to optimize the concentration and purification of the virus for rabies vaccine production.METHODS: First of all, the Pasteur virus strain (PV) was cultured by using BHK 21 cells with DMEM media contain bovine fetal serum (7 %) for five days. Subsequently, the virus purification was done via tangential flow filtration (TFF) system. The quality of purifying viruses was an assessment with titration and SDS-PAGE. Secondly, the virus inactivation was optimized using Minitab software based on three factors, namely time, temperature, and concentration. Afterwards, the inactivity of the samples was tested on mice. Finally, the virus potency was evaluated by the National Institute of Health (NIH) method.RESULTS: The viral titration test in TFF samples revealed that viral titer increased in comparison with the control group (P<0.05). The SDS-PAGE analysis of the purified and concentrated samples showed that the purified virus via TFF had a higher purity compared to the not-concentrated samples. Moreover, the NIH test indicated a 10-fold increase in potency result in the TFF group.CONCLUSIONS: The present study implied that the TFF method is highly suitable for condensation and purification of a high volume of viral fluid and could be applied on an industrial scale to increase the potency of the vaccine produced.

BACKGROUND: As the population grows, there is further need to food, and fish is not an exception. Several fish species are potential sources of common parasites between humans and fish. One of the important diseases common between human and fish is Anisakiasis. The parasitic agent of this disease is the larval stage of the Anisakid family nematodes, including Pseudoterranova and Anisakis.OBJECTIVES: In this study, Epinephelus fish, one of the edible and commercial valuable fishes of the Oman Sea, was examined for the presence of nematodes of the Anizakidae family.METHODS: Fifteen out of the 26 specimens were infected with Nematodes. Nematodes were isolated from fish abdominal area. For morphological study, each nematode sample was first clarified with lactophenol. Subsequently, it was examined using an optical microscope. After morphological examination of these nematodes, DNA extraction was performed. Using primers related to a part of cytochrome oxidase subunit 1 (Cox1), PCR products were 710 bp for PCR reaction. Finally, the amplified fragment was sequenced.RESULTS: The larvae were about 1 to 3 cm long, white, and often twisted. At the anterior end of the parasite, a button was seen, and in some larvae, a terminal spine was observed. In certain larvae, a small abdomen at the end of the esophagus can be seen. Out of the obtained 26 nematode specimens, eight Anisakis specimens were identified following morphological analysis. These specimens had terminal spines and three anterior lips. After sequencing, Pseudoterranova nematode was identified to belong to aniakidae family. Separate clad tree showed paraphylitic for isolated Pseudoterranova.CONCLUSIONS: Morphological examination categorized isolated larvae as the Anizakidae family. Other molecular results of this nematode showed Pseudoterranova krabbei. The results of sequencing this parasite were recorded in the gene bank under the Accession number: MK317965. This nematode was initially isolated from the Oman Sea Epinephelus fish.

BACKGROUND: Omega-3 fatty acids can be conducive toreducing the harmful effects of physiological stress through reducing the stimulatory activity of glutamatergic neurons.OBJECTIVES: The aim of this study was to investigate the effects of omega-3 fatty acids on performance, blood parameters, and the profile of fatty acids in the egg yolks of laying hen under stress.METHODS: This study was performed using 96 LSL-Lite laying hens in a 2 × 3 factorial experiment with 2 factors, namely stress (no dexamethasone and 1.5 mg/kg of diet dexamethasone) and omega-3 fatty acids (the levels of 0, 0.24 and 0.48 % of diet), in a completely randomized design for 70 days from 35 to 44 weeks of age.RESULTS: Physiological stress reduced the feed intake, the percentage of egg production, and egg mass in laying hens (P<0.05). Omega-3 fatty acid supplements had no effects on these traits. The groups receiving 0.48 % of omega-3 fatty acids had the lowest heterophil:lymphocytes (P<0.05), and there was no difference between stressed and non-stressed groups. The ratio of omega-6 to omega-3 fatty acids was higher in birds previously affected by stress (P<0.05). Feeding with omega-3 fatty acids in birds increased omega-3 fatty acids in egg yolk and reduced the ratio of omega-6 fatty acids to omega-3 in laying hens (P<0.05).CONCLUSIONS: Based on the results of this experiment, physiological stress had a negative effect on performance traits, and the use of omega-3 fatty acids in laying hens under stress had no effect on performance traits. Physiological stress altered the profile of fatty acids and increased the proportion of omega-6 to omega-3 fatty acids in egg yolk. The use of omega-3 fatty acids reduced the negative effects of stress and improved the profile of fatty acids in egg yolk.

BACKGROUND: Optimal levels of minerals in the diet are crucial for improving performance and immune response against the environmental stresses.OBJECTIVES: This study was conducted to evaluate the effects of water supplementation of chelated trace mineral (CTM) on growth performance, hematology, blood biochemistry, antioxidant status, and antibody response in broilers reared under heat stress condition.METHODS: A total of 240 male Ross 308 broiler chickens were randomly allocated into one of the following five treatments (each consisting of four replicates): (1) positive control (PC; thermoneutral condition), (2) negative control (NC; heat stress condition), (3) low-CTM (NC + low CTM level in tap water), (4) medium-CTM (NC + medium CTM level in tap water),  and (4) high-CTM (NC + high CTM level in tap water). The CTM levels in the tap water for the low-CTM treatment were 0.1, 0.15, 0.3, 0.4, and 0.45 mg/bird/day on days 1-10, 11-20, 21-30, 31-40, and 41-50, respectively. The respective values were 1.0, 1.5, 3.0, 4.0, and 4.5 for the medium-CTM, and 10, 15, 30, 40, and 45 mg/bird/day for the high-CTM water.RESULTS: The average weight gain during the whole experimental period in the medium-CTM treatment was higher compared to that in the negative control treatment, but lower than that in the positive control treatment (P<0.05). The heterophil/lymphocyte ratio and total antibody titers against Newcastle disease in the medium-CTM and high-CTM groups were similar to those of the broilers in the PC group, yet better (P<0.05) those of the NC group. The serum superoxide dismutase activity was also higher (P<0.05) in the high-CTM group compared to that of the NC group.CONCLUSIONS: The results suggested that the water supplementation of CTM at a moderate level (1.0, 1.5, 3.0, 4.0, and 4.5 mg/bird/day during different rearing periods) could be a strategy to ameliorate the detrimental effects of heat stress in broilers.

BACKGROUND: Open wounds affecting the distal part of limbs are commonly seen in horses. Due to certain factors, such as limited connective tissue available, potentiated growth of excessive granulation tissue, risk of contamination, and poor response to common treatments, healing of these wounds becomes a major problem for veterinarians on a number of occasions. Application of Mesenchymal Stem Cells (MSC) for enhancing wound healing has received a great deal of scientific attention. Among the MSCs, those derived from adipose tissue are frequently used owing to their availability, large number of cells after the primary harvest, and the capacity to differentiate to different cell lines.OBJECTIVES: The current study aimed to evaluate type 1 and 3 collagen genes expression in horse distal limb wounds treated via adipose-derived Mesenchymal Stem Cells and its comparison with bone marrow-derived stem cells.METHODS: After treatment of the experimental open wounds created in the distal limbs of four horses via autologous MSCs, real-time PCR was used for evaluating and comparing the expression of type I and III collagen genes in the healing wounds.RESULTS: Significant differences in the expression of type I and III collagen genes were observed between the treatment groups. Despite the fact that the greatest collagen genes expression belonged to bone marrow-derived MSCs, no significant differences were seen with adipose-derived MSCs.CONCLUSIONS: Owing to the advantages and an acceptable performance, adipose-derived MSCs could be considered as a novel approach to enhancing limb wound healing in horses.

BACKGROUND: During the modification of several races, which has been done on chickens, there have been several changes in the function of neural pathways and receptor density involved in the control of food intake and appetite. Melanocortin system and its receptors are involved in the central regulation of nutritional behaviour and energy balance. Therefore, this study was designed to investigate the role of this system in the central control of food and water intake in birds.OBJECTIVES: The present study aimed to evaluate the role of MCR3 and MCR4 receptors in controlling the food and water intake in birds.METHODS: This work was performed on 48 Ross 308 broiler chicks through two experiments (each experiment in four groups). Primarily, stereotaxic surgical guide cannula was implanted in the chickens. Subsequently, in the first experiment, the chickens were divided into the four following groups: the control solution, 0.2, 2, and 10 nmol/5µl of SHU9119 (Non-selective antagonist of MCR3 and MCR4 receptors) In the second experiment, the chickens were also divided in four groups: the received control solution, 0.2, 2, and 10 nmol/5µl of MCL0020 (Selective MCR4 receptor antagonist) via intracerebroventricular (ICV) injection. Afterwards, cumulative food and water intake were measured at 30, 60, 90, 120, 150, and 180 minutes after the injection.RESULTS: The results of this study showed that ICV injection of SHU9119 and MCL0020 increased cumulative food intake (P>0.05), but did not affect cumulative water intake (P<0.05).CONCLUSIONS: According to the findings herein, central melanocortin system is one of the systems involved in central control of food intake in birds.

BACKGROUND: Tilapia, Oreochromis niloticus, is an omnivorous and important breeding species in the world. Over the recent years, tilapia breeding has begun in Iran. In aquaculture, it is very important to regulate a balanced diet in terms of nutrients needed for growth, which would be also economically appropriate.OBJECTIVES: The main objective of this study was to investigate the effect of substituting chicken waste powder in the diet of fish at levels of 0, 25, 50, 75, and 100 % on the tissue structure of different parts of the intestine of Nile tilapia.METHODS: 75 fish (three frequency per treatment) were fed with chicken waste powder instead of fish meal in their diet for eight weeks at 0, 25, 50, 75, and 100 % levels. At the end of the treatment, separate samples were taken from the initial, middle, and end parts of the intestine. After passing the usual histological steps, the slides were assessed by hematoxylin-eosin staining and TUNEL immunohistochemistry technique.RESULTS: In histometric studies, the highest villi height, thickness, muscle layer, and number of goblet cells were reported in the control group and the lowest in the 100 % group. In immunohistochemical studies, the number of apoptotic cells in groups 75 and 100 % was higher than that in the other groups.CONCLUSIONS: According to the results of the present study, it could be suggested that the replacement of chicken waste powder instead of a fish meal up to 50 % for indigo tilapia is tolerable. However, higher levels of chicken waste powder will reduce absorption, and acceptance of food and have adverse effects on growth.