Affiner votre recherche
Résultats 31-40 de 546
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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]A Serological Study of Neospora caninum Infection in Dairy Cattle in Semnan Province, Iran
2021
Binaei, Marziyeh | Changizi, Emad | Staji, Hamid
BACKGROUND: Over the recent years, Neospora caninum has been one of the most important causes of abortion in dairy cattle. OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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).
Afficher plus [+] Moins [-]The Effect of In Ovo Injection of Fadrozole Hydrochloride, Nettle Extract and Mushroom Extracts on Sex Reversal, Performance Traits, Blood Lipids and White Blood Cells and Muscle Structure of Broiler Chicks
2021
Mokarrami, Tohid | Navidshad, Bahman | Hedayat Evrigh, Nemat | Mirzaei Aghjegheshlagh, Farzad
BACKGROUND: It is possible for Sex reversal of eggs with female embryo using anti-aromatase agents, and the hatchlings have an improved performance. OBJECTIVES: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.
Afficher plus [+] Moins [-]Effect of Silver Nanoparticle (SNP) on Productive and Reproductive Performances in Japanese Quail
2021
Farzinpour, Amjad | Sobhani, Keyvan
BACKGROUND: Due to the numerous biological effects of nanoparticles, nanotechnology can play a major role in future research areas in the poultry industry. OBJECTIVES: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.
Afficher plus [+] Moins [-]