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Study of the Effect of Cuminum Cyminum Nanoemulsion on the Microbial and Organoleptic Properties of Chicken Fillet at 4 °C
2021
Fallah Aski, Talaye | Tooryan, Fahimeh | Azizkhani, Maryam | Shahavi, Mohammad Hassan
BACKGROUND: Microbial growth and unfavorable taste and aroma are the leading reasons of meat spoilage under refrigerated temperatures. Today, plant essential oils are good alternatives to synthetic preservatives. In the meantime, nanotechnology has been instrumental in helping to apply the most effective plant compounds on the target cell. OBJECTIVES: The present study aimed to identify the compounds of essential oil of Cuminum cyminum and to investigate the microbial counts (total count, psychrotrophs, lactic acid bacteria, mold and yeast) after preparation of nanoemulsions of cumin essential oil via ultrasonic method and its nanoemulsions. Moreover, herein, we intended to evaluate organoleptic in chicken fillet samples under temperature of 4 °C. METHODS: The essential oil components were analyzed with GC / MS and the effects of Cuminum cyminum essential oil nanoemulsion were examined on microbial count and organoleptic properties in terms of color, odor, and overall acceptance (with 9-point hedonic scale) on Cuminum cyminum EO nanoemulsions in chicken fillets under 4 °C. RESULTS: The major identified components of Cuminum cyminum by extraction time were: beta- pinene (8.90 %), benzene- methyl (16.51 %), gamma- terpene (13.39 %), propanal (29.43 %), 1 -Isopropylidene-3-N-butyl2-cyclobutene (6.52 %), and benzene methanol (8.36 %). The results of microbial count at the last day of storage showed that the treatment containing 20 % and 25 % nanoemulsions significantly delayed microbial spoilage compared to other treatments (p < /em><0.05). The control treatment also indicated the highest level of microbial spoilage; as represented in Log 6, the maximum bacterial count in chicken fillets and the shelf life of BHT at 0.02 % concentration continued until day 3. Furthermore, in organoleptic evaluation, 20 % and 25 % nanoemulsion treatment scored higher than other treatments. CONCLUSIONS: Nanoemulsions of Cuminum cyminum EO at concentrations of 20 % and 25 % were able to delay the microbial spoilage of chicken fillets and produced organoleptically favorable results.
显示更多 [+] 显示较少 [-]Effect of Ethanol Extract of Zataria Multiflora on Ichthyophthirius Multifiliis Tomonts and Theronts in Danio rerio
2021
Rahmati-Holasoo, Hooman | Javadi Moosavi, Mahsa Sadat | Ebrahimzadeh Mousavi, Hosseinali | Mirzargar, Seyed Saeed | Taheri Mirghaed, Ali
BACKGROUND: Medicinal plants have a long history in the treatment of parasitic diseases and are usually free of side effects. Removing and killing tomonts and theronts of this parasite can prevent the parasite pathogenicity in fish. OBJECTIVES: The present study aimed to investigate the inhibitory effect of ethanolic extract of Zataria multiflora on both free and parasitic life stages. METHODS: Three soluble forms of Zataria multiflora extract (80 ml/L) were prepared, which contained freshly prepared solution, stored solution at room temperature for one month and stored solution at refrigerator for one month. Afterwards, different dilutions were prepared for each of the solutions and the tomonts and Theronts were treated with different dilutions of the extract. RESULTS: Zataria multiflora extract can kill all theronts at concentrations of 20 ml/L during 6.04 to 6.37 min and concentration of 10 ml/L during 31/2 to 32.4 min, respectively. However, at these concentrations, only 3.46-6.11 % of tomonts were killed herein after 4 hours. CONCLUSIONS: Tomonts were found to be more resistant to the parasiticides than theronts. The use of Zataria multiflora extract significantly reduced tomont reproduction and decreased Ich infectivity prevalence and intensity. Zataria multiflora extract prevented Ich infestation in naive fish and effectively treated infected fish.
显示更多 [+] 显示较少 [-]The Role of Glycine and Strychnine-Sensitive Receptors on Food Intake Induced with Dopamine in Neonatal Broilers
2021
Rahimi, Jamal | Zendehdel, Morteza | Khodadadi, Mina
BACKGROUND: The regulation of appetite and food intake in birds are implemented as complex homeostatic mechanisms at different levels of control. OBJECTIVES: The current research aimed to investigate the effects of glycine and strychnine-sensitive receptors on food intake induced with dopamine in neonatal broiler-type chickens. METHODS: This study was conducted in five experiments (each consisting of four treatment groups with 12 birds). In experiment 1, chickens in the control group received intracerebroventricular (ICV) injection of saline (with 0.1 % Evans Blue) and different doses of dopamine (10, 20, and 40 nmol) in treatments groups 2-4, respectively. Experiments 2 and 3 were designed similar to the experiment 1 except for the fact that chickens received different doses of glycine (50, 100, and 200 nmol) and strychnine (50, 100, and 200 nmol) instead of dopamine. Experiment 4 was performed to investigate the mediatory role of strychnine (100 nmol) on food intake induced with dopamine (40 nmol). Moreover, experiment 5 investigated the interaction between non-effective doses of glycine (50 nmol) and dopamine (10 nmol) and their interplay on food intake. Afterwards, cumulative food intake based on bodyweight percentage (BW %) was measured at 30, 60, and 120 minutes after the injection. RESULTS: The obtained findings revealed that effective doses of dopamine and glycine dose-dependently induced hypophagia in neonatal meat-type chickens (p < /em>≤0.05). In addition, injection of strychnine increased food intake and also inhibited the hypophagic effect induced by dopamine (p < /em>≤0.05). Furthermore, co-administration of non-effective doses of glycine and dopamine significantly decreased food intake compared to the groups which only received dopamine or glycine (p < /em>≤0.05). CONCLUSIONS: Our findings suggested that strychnine-sensitive receptors may have a mediatory role in food intake induced by dopamine. Additionally, it seems that glycine and dopamine probably have synergistic effects on food intake control in neonatal meat-type chickens.
显示更多 [+] 显示较少 [-]Evaluating the Accuracy of the Diagnosis of Subclinical Mastitis Using Lactate Dehydrogenase-Based Dipsticks
2021
Sajadi, Seyed Saeid-Reza | Khoramian, Babak | Azizzadeh, Mohammad | Farzaneh, Nima
BACKGROUND: Mastitis could be detected in various ways, including physical, on-farm, and laboratory tests. OBJECTIVES: The present research aimed to evaluate the accuracy of the diagnosis of mastitis using lactate dehydrogenase (LDH)-based dipsticks and to assess these dipsticks with regard to the effects of different lactation days, the amount of milk production, and parity. RESULTS: Considering bacteriologic culture as a gold standard method for the diagnosis of subclinical mastitis, the sensitivity and specificity of LDH test were 68.9 % and 54 %, respectively. The results revealed a high correlation between SCC and LDH. A statistically significant relationship was observed between the response of dipstick and CMT results; with the increase in the CMT score, the score of LDH dipstick increased. By investigating the effects of lactation days, the amount of milk production, and parity, it was determined that the chance of having subclinical mastitis in cows with positive dipstick result was 5.59 times greater than that in cows with negative dipstick result. There were no significant relationships among SCC, LDH, and CMT with lactation days and milk production; meanwhile, with the increase in parity, the three above-mentioned variables showed significant increase. CONCLUSIONS: The results of the present study indicated that the best methods for subclinical mastitis detection were SCC, CMT, and LDH based dipsticks, respectively.
显示更多 [+] 显示较少 [-]Radiographic and Ultrasonographic Diagnosis of Avulsion Fracture in Metacarpal Bone of Two Thoroughbred Foals
2021
Soroori, Sarang | Tavakoli, Amir | Shateri Amiri, Banafsheh
HISTORY: Suspensory ligament injury associated with avulsion or crescent fracture of third metacarpal or metatarsal bone is a common injury in racehorses. Lameness is known to be the most common clinical sign of these horses. CLINICAL FINDING: The present article investigated two avulsion fractures in the third metacarpal bone in 2.5-year-old mare and stallion, which had chronic lameness with a vague origin and disability of weight bearing in left forelimbs. DIAGNOSTIC TESTS: Following radiography and ultrasonography examinations, suspensory ligament injury and subsequently avulsion fracture in the proximal third of metacarpal bones in left forelimb were approved. FINAL EVALUATION: In radiography, radiolucent lines associated with fragmented segments (about 2×6×8 mm) in mare and (about 2×4×6 mm) in stallion in the proximal part of the third metacarpal bone were indicative of an avulsion or crescent fracture at the origin of the suspensory ligament. Furthermore, in ultrasonography compatible with radiographic findings, an echogenic-fragmented fracture in the proximal part of the third metacarpal bone and a local area of decreased echogenicity was diagnosed as desmopathy of suspensory ligament.
显示更多 [+] 显示较少 [-]Identification of Intestinal Parasites of Laboratory Mice inThree Animal Houses in Tehran
2021
Dehghani, Mohadesse | Ebrahimzadeh, Elahe | Hosseini, Seyyed Hossein | Nikpay, Ali | Ahoo, Mohammad Bagher
BACKGROUND: Mice are the most common laboratory animals used in research. Parasitic infections in laboratory animals affect both the research results and the health of researchers.OBJECTIVES: The present study aimed to investigate the infection status of intestinal parasites of mice in three main animal houses in Tehran.METHODS: In this study, 75 mice (25 from each animal house) were randomly purchased from an animal breeding house in Tehran and investigated. Mice were euthanized and autopsied. In order to study the gastrointestinal protozoa, wet smears were prepared from different parts of the intestine and feces and stained with Giemsa and Ziehl-Neelsen if necessary. Afterwards, the intestinal contents were examined and helminths were separated. If necessary, specific staining was used to diagnose helminths.RESULTS: Among the detected parasites, Aspiculuris tetraptera was the most prevalent (% 93.3). The mice were also infected with Syphacia obvelata (% 62.6), Hymenolepis nana (% 61.3), Tritrichomonas muris (% 22.6), Giardia muris (% 21.3), Spironucleus muris (% 18.6), Hymenolepis diminuta (% 17.3), and Cryptosporidium (% 6.6).CONCLUSIONS: Out of 75 adult mice studied, all had at least one parasite. This can affect the research results and jeopardize the health of researchers and related personnel.
显示更多 [+] 显示较少 [-]Antibacterial Properties Study of Synthetic Nanocomposite Zinc Chromite-Zinc Aluminate (ZnCr2O4-ZnAl2O4) Against Escherichia coli and Pseudomonas aeruginosa
2021
Taheri, Ali | Ziaadini, Morteza | Gahramzai, Masumeh
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.
显示更多 [+] 显示较少 [-]Effects of Water Supplementation of A Chelated Trace Mineral Blend on Growth Performance, Blood Parameters, Antioxidant Status, and Immune Response of Broilers Under Heat Stress Conditions
2021
Eidi, Majid | Ghasemi, Hossein Ali | Hajkhodadadi, Ima | Moradi, Mohammad Hossein
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.
显示更多 [+] 显示较少 [-]The Effect of Replacement of Poultry by-Product with Fish Meal in the Diet of Nile Tilapia (Oreochromis niloticus) on their Intestine Histology
2021
Basir, Zahra | Peyghan, Rahim
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.
显示更多 [+] 显示较少 [-]Effects of Different Levels of Thymus vulgaris Extract in Comparison with Antibiotics, Vitamin C and Vitamin E on Performance, Blood Biochemistry and Antibody Response in Broiler Chickens Under Heat Stress Condition
2020
Rostami, Leili | Taherpour, Kamran | Akbari Gharaei, Mohammad | Ghasemi, Hossein Ali | Jamali, Jabbar
BACKGROUND: Thyme extract has the antimicrobial and antioxidant components that can be useful for the broilers under heat stress condition. OBJECTIVES: This experiment was conducted to investigate the effects of Thymus vulgaris extract in comparison with some common feed additives on performance, blood biochemical parameters and antibody response in broiler chickens under heat stress conditions. METHODS: This study was conducted using 192 one-day-old male broiler chicks (Ross 308) in a completely randomized design with 8 treatments in 4 replicates and 6 chicks per replicate. Treatments were as follows: 1) basal diet + standard temperature conditions (positive control); 2) basal diet + heat stress conditions (negative control); 3) negative control + 200 mg virginiamycin; 4) negative control + 150 mg Protoxin probiotic, 5) negative control + 250 mg vitamin C, 6) negative control + 250 mg vitamin E, 7) negative control + 250 mg thyme extract, and 8) negative control +500 mg thyme extract per kg diet. RESULTS: Dietary thyme extract at the rate of 500 mg/kg as well as probiotic and vitamin E increased (P<0.05) body weight gain (2202, 2183 and 2199, respectively) and improved feed conversion (1.65, 1.74 and 1.66, respectively) compared with negative control group (body weight gain 1960 g and feed conversion ratio 1.96). Moreover, 500 mg/kg dietary thyme extract, probiotic and vitamin C reduced triglycerides, total cholesterol and low density lipoprotein during heat stress conditions (P<0.05). All dietary supplements groups significantly increased antibody titers against red blood cells as compared with negative control. CONCLUSIONS: In general, the results of the present study suggest that thyme extract at the level of 500 mg/kg of diet can be recommended as an alternative to the common feed additives to improve growth performance and health benefits of the heat-stressed broilers.
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