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.

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.

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.

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.

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: 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: 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.

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.

BACKGROUND: Rotavirus Group A is one of the most important causes of gastroenteritis as it is isolated from 30 to 50% of infant diarrhea from humans and other animals. G genotype of the virus is determined by gene sequence of a surface protein of the virus (VP7), one of the most important factors in inducing immunity against the virus which acts very specific to each genotype. OBJECTIVES: In the present study the presence of common bovine rotavirus genotypes A was examined in human rotavirus population. METHODS: A total of 100 stool samples from children under 2 years of age in Tehran and Varamin were collected and to track the presence of rotavirus A, were evaluated using ELISA method. Positive samples were isolated and cultured on the MA-104 cell line after several passages. The positive samples (49 samples) were determined to be the G type using semi-nested RT-PCR and primers specific for bovine common genotype. RESULTS: From 100 samples, 49 were positive in ELISA. Eight samples in the first semi nested RT-PCR showed the desired rotavirus bands and in the second round, the results were positive for the presence of bovine VP7 in two samples taken from Varamin, in one sample, G6, and in another sample, two genotypes of VP7, G6 and G8 were detected, indicating infection with at least two strains of human rotavirus reassortant. Six of the ELISA selected positive samples that were taken to the cell line MA104, showed effects of cell damage (CPE) after 4-5 consecutive passages, demonstrating proliferation of the rotaviruses of this study and so, their viability was confirmed. CONCLUSIONS: The results of this study indicate reassortment between bovine and human rotaviruses and show that in case of occurrence of bovine and human rotavirus infection and the emergence of new human type, due to reassortment strain differences in protein immunogen it is possible to overcome due to lack of maternal immunity in the human population and low efficiency of current vaccines and, ultimately, epidemic and considerable losses may occur. Hence, more research is warranted.

Cardiac thrombosis normally occurs in old Syrian hamsters and according to the research it has a higher incidence rate in females than males. The most frequent site of thrombus formation has been reported to be the left atrium and it usually occurs secondary to degenerative cardiomyopathy and amyloidosis. In this study during a period of 2 years, 22 pet Syrian hamsters aged between 1-3 years-old with signs of cardiovascular disease and referred to the small animal Veterinary Teaching Hospital of University of Tehran were examined in order to evaluate for cardiac diseases as well as atrial thrombosis. During the examinations and observations clinical signs such as lethargy, anorexia, hyperpnoea, reduced daily activity, tachycardia, cyanosis, and vaginal discharge were observed. Based on the clinical sings, the initial diagnosis of cardiac disease was made and for more accurate evaluation of cardiac disease, the cases were referred to the radiology department. For detection of specific signs of cardiac disease echocardiography was performed on all patients. in some cases, sampling of vaginal discharge was taken as well and transferred to the lab for bacterial culture. Cardiac thrombosis and especially atrial thrombosis in all cases were diagnosed by echocardiography so that 9 cases showed pyometra concurrently.