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71.
Oxytocin neurons have a physiological role in food intake and energy balance. Several studies have shown that central histaminergic and adrenergic systems synapse on oxytocin neurons but there is no information for their interaction on food intake regulation in birds. The purpose of this study was to examine the effects of intracerebroventricular (ICV) injection of α-fluoromethylhistidine (α-FMH, histidine decarboxylase inhibitor), chlorpheniramine (histamine H1 receptors antagonist), famotidine (histamine H2 receptors antagonist), thioperamide (histamine H3 receptors antagonist), prazosin (α1 receptor antagonist), yohimbine (α2 receptor antagonist), metoprolol (β1 adrenergic receptor antagonist), ICI 118,551 (β2 adrenergic receptor antagonist) and SR59230R (β3 adrenergic receptor antagonist) on oxytocin-induced hypophagia in 3-h food-deprived (FD3) neonatal broiler chicken. In Experiment 1, 3 h-fasted chicks were given an ICV injection of saline, α-FMH (250 nmol), oxytocin (10 μg) and co-injection of α-FMH + oxytocin. Experiments 2–9 were similar to experiment 1 except birds were injected with chlorpheniramine (300 nmol), famotidine (82 nmol), thioperamide (300 nmol), prazosin (10 nmol), yohimbine (13 nmol), metoprolol (24 nmol), ICI 118,551(5 nmol) and SR59230R (20 nmol) instead of α-FMH, respectively. After injection cumulative food intake was measured until 120 min post injection. According to the results, ICV injection of oxytocin significantly decreased food intake in broiler chickens (P < 0.001). ICV injection of α-FMH significantly attenuated hypophagic effect of oxytocin (P < 0.001). Also, co-injection of chlorpheniramine plus oxytocin significantly decreased the effect of oxytocin on food intake (P < 0.001). Co-administration of thioperamide and oxytocin significantly amplified hypophagic effect of oxytocin in chickens (P < 0.001). In addition, ICI 118,551 attenuated hypophagic effect of oxytocin (P < 0.001); while famotidine, prazosin, yohimbine, metoprolol and SR59230R had no effect on oxytocin- induced food intake in FD3 broiler chickens. These results suggest that the effect of oxytocin on food intake is probably mediated by histaminergic (via H1 and H3 receptors) and noradrenergic (via β2 receptors) systems in broiler chickens.  相似文献   
72.
Respiratory diseases in calves are responsible for major economic losses in both beef and dairy production. Several viruses, such as bovine respiratory syncytial virus (BRSV), bovine herpes virus-1 (BoHV-1), bovine parainfluenza virus-3 (BPI-3V), bovine viral diarrhea virus (BVDV), and bovine adenoviruses (BAV), are detected in most clinical cases with respiratory signs. The aim of this study is to define seroprevalences of five major viral causes of bovine respiratory infections in cattle in central region of Iran (Esfahan province). The population targeted was 642 dairy cows (Holstein–Friesian) from 25 farms. Samples of blood serum from female cattle were examined. Sera were tested by commercial ELISA kits to detect antibody against BRSV, BoHV-1, BPI-3V, BVDV, and BAV-3. The results were analyzed by Chi-square test. In the present study, seroprevalences of BRSV, BoHV-1, PI3V, BVDV, and BAV-3 were 51.1%, 72%, 84.4%, 49.2%, and 55.6%, respectively. The present study shows that infections of bovine respiratory viruses are very common in cattle in Esfahan.  相似文献   
73.
The aim of this study was to evaluate the blood serum and diet concentrations of copper, zinc, and iron in Holstein dairy cattle kept under semi-industrial farming in Isfahan province, central Iran. Moreover, the effects of season, pregnancy, and daily milk yield on serum Cu, Zn, and Fe concentrations were also evaluated. The study was carried out on 12 semi-industrial Holstein dairy cattle farms. A total of 120 blood serum samples (60 in each season) and 24 diet samples (12 in each season) were collected in the summer and winter. The Cu, Fe, and Zn contents were assessed in samples using atomic absorption spectrophotometer. In the summer, the mean concentrations of Cu and Fe in serum samples were lower and higher than the critical level, respectively (P < 0.05). In total diet samples, the mean concentrations of Zn were significantly higher than critical level (P < 0.05). In summer, winter, and total diet samples, the mean concentrations of Fe were significantly higher than critical level (P < 0.05). The serum Cu and Zn concentrations were significantly higher in the winter than those determined in the summer (P < 0.05). The serum Cu concentrations were significantly higher in nonpregnant than those in pregnant dairy cattle (P < 0.05). No significant difference was observed in serum Cu, Zn, and Fe concentrations of dairy cattle in different daily milk yield groups. It can be concluded that Holstein dairy cattle reared under semi-industrial dairy farming were deficient in serum Cu concentrations, especially in summer. Further, high level of Fe in blood serum might be due to feeding of cattle with diet containing excess quantity of Fe.  相似文献   
74.
Interaction of binary mixture of the two sulfonylurea herbicides: foramsulfuron or nicosulfuron with 2,4-D + MCPA, was evaluated in greenhouse experiments during 2010 and 2011 applying the additive dose model. Plants of redroot pigweed, common lambsquarters, common purslane and black nightshade were sprayed with seven doses of herbicides alone and in binary fixed-ratio mixtures. In total, 35 binary mixtures were studied in 7 separate experiments at ED90 response level. Results indicated that mixture of foramsulfuron + 2,4-D + MCPA was synergistic on redroot pigweed compared to additive interaction between nicosulfuron and 2,4-D + MCPA. Mixture of foramsulfuron + 2,4-D + MCPA was slightly antagonistic on common lambsquarters and an additive interaction was observed with both foramsulfuron and nicosulfuron + 2,4-D + MCPA on common purslane. Finally, the mixture of foramsulfuron or nicosulfuron + 2,4-D + MCPA on black nightshade was antagonistic especially in mixtures where the ratio of sulfonylurea herbicides was more than 2,4-D + MCPA. Totally, 2,4-D + MCPA in mixture with sulfonylurea herbicides especially foramsulfuron provided better control of redroot pigweed in comparison with herbicides applied alone and other herbicide mixtures on weeds.

Abbreviations: 2,4-D + MCPA: ((2,4-Dichlorophenoxy) acetic acid plus (4-chloro-2-methylphenoxy) acetic acid); ADM: additive dose model; a.i.: active ingredient; ALS: acetolactate synthase; DAT: days after treatment; ED: effective dose; Foramsulfuron: (2-(N-((4,6-dimethoxypyrimidin-2-yl)carbamoyl)sulfamoyl)-4-formamido-N,N-dimethylbenzamide); Nicosulfuron: (2-[(4,6-dimethoxypyrimidin-2-yl)carbamoylsulfamoyl]-N,N-dimethylpyridine-3-carboxamide).  相似文献   

75.
Tropical Animal Health and Production - Infectious bronchitis virus (IBV) is a highly infectious pathogen, which affects the respiratory tract, reproductive system, and kidney of chickens. Many...  相似文献   
76.
Rangeland-based animal husbandry has been frequently exposed to the vagaries of weather. While the current rates of climate variability are unprecedented in arid and semiarid regions, climate change is expected to put further pressure on rangelands with medium- and poor-quality forages and increase the vulnerability of households who mainly depend on livestock production. Therefore, it is imperative to ensure that livestock producers increase their resilience to climate variability or change. However, few field-based studies have focused on simultaneous investigation of both vulnerability and adaptation of livestock keepers to climate-related risks. To fill this gap, a field-based research study was conducted in southwest Iran. A survey of 274 herder families, selected using a cluster sampling technique, revealed low, medium and high levels of vulnerability, which were principally distinguished by various degrees of exposure, sensitivity, and adaptive capacity. Further, this study identified the main adaptation strategies employed by the herders of this region (i.e., purchasing fodder; rotational grazing; raising a mixed-herd, on-farm occupation; and postharvest grazing). Results indicated that most herder families applied traditional adaptation strategies in response to climate variability. Findings revealed that herders had to reduce their livestock due to low adaptability. Loan term, purchasing insurance, level of exposure, income, experience, response efficacy, and knowledge were the major determinants of the herders’ adaptation decisions. To increase the resilience of livestock producers against climate change, restructuring traditional livestock production systems, producing participatory knowledge and information for sustainable management of rangelands, and designing or redesigning effective adaptation strategies are required.  相似文献   
77.
The teaching of pathology within the veterinary medical curriculum extends through the entire training period and has a dual role. General pathology deals with principles of disease processes as a basis for understanding the reactions of a multi-cellular organism to adverse effects; organ pathology builds on the principles of general pathology and explains the malfunctions of individual organs. Pathology is heavily image dependent and best taught in a highly interactive manner. The Institute of Veterinary Pathology, University of Zurich (IVPZ), has been actively developing concepts for teaching pathology in the new veterinary curriculum, which demands more active participation from students, with 20% of their study time devoted to individual study using traditional materials (books, articles, etc.) and e-learning modules. The Swiss Virtual Animal Pathologist is designed to cover and support the central elements of the Veterinary Pathology curriculum of the Vetsuisse Faculty. The needs of students and staff of the participating institutions for an interactive learning platform to supplement the existing face-to-face lectures and tutorials are the highest priority of this initiative.  相似文献   
78.
This study was conducted to evaluate possible alteration in the activity of arginase, an important enzyme of cell proliferation and vascular smooth muscle contraction regulator in diabetics, that may be correlated with low fertility in diabetic patients. In this investigation, 6 apparently healthy adult male dogs were selected and divided in two groups, diabetics and non-diabetics. Diabetes mellitus was induced in one group by intravenous (IV) injection of alloxan (100 mg/kg). Dogs with a fasting blood glucose (FBS) of more than 200 mg/dl were considered to be diabetic. Four weeks following induction of diabetes mellitus, the animals in both groups were anesthetized by an IV injection of sodium thiopental. Livers and whole reproductive systems, including the testes, penis, urethra, and prostate, were dissected. The epididymides, corpus cavernosum, corpus spongiosum, penile urethra, and vas deferens were also dissected and removed from the reproductive system. Arginase activity and total protein were measured by the urea and Lowry's methods respectively in above mentioned sections. Plasma testosterone was determined by the radioimmunoassay method. The results showed significantly (P<0.05) increased arginase specific activity (ASA) in the liver, epididymis, prostate, corpus cavernosum and corpus spongiosum of the diabetic dogs. In the reproductive system of the diabetic dog, the maximum and minimum ASA was seen in the corpus cavernosum and testes, respectively (105.12 +/- 8.76 vs. 25.0 +/- 0.55). No such variation was observed in the ASA of normal dogs (39.0 +/- 5.47 vs. 25.0 +/- 5.47). There was no significant difference in plasma testosterone level between the groups. In conclusion, diabetes increased the ASA in liver, prostate, epididymis, corpora cavernosa, and corpora spongiosum of the male dogs and may contribute to erectile dysfunction or low fertility in diabetics.  相似文献   
79.
Numerous approaches have been developed to quantify forest structure modules.A variety has measured each as part of stand attributes.This study was carried out in managed mixed stands in northern Iran.The objective was to quantify stand structure and its variation before and after tree marking through the Gini index and structural triangle method.A full sampling inventory was taken in 2004 and 2014 at the beginning and end of a period,before and after tree marking operations in five stands.The results indicate that the Gini index was 39.5,62.2,43.0,82.0 and 74.0%forⅠ,Ⅱ,Ⅲ,ⅣandⅤstands respectively.Furthermore,approximate structural diameters were determined as a large category forⅠ,Ⅱ,ⅢandⅤstands while standⅡhad an intermediate-large class pre-tree marking to an intermediate-small class post-tree marking.The paired t-test results were not significant for tree numbers and growing stock changes for all species,and for beech,hornbeam,and velvet maple before and after tree harvesting in the whole stand.Therefore,the Gini index and the structural triangle method can be used for natural stand modeling,structural diversity designation,and for management practices in nature-oriented forestry strategies.  相似文献   
80.
Background: Wound healing of burned skin remains a major goal in public health. Previous reports showed that the bone marrow stem cells were potent in keratinization and vascularization of full thickness skin wounds. Methods: In this study, mesenchymal stem cells were derived from rat adipose tissues and characterized by flowcytometry. Staining methods were used to evaluate their differentiation ability. A collagen-chitosan scaffold was prepared by freeze-drying method and crosslinked by carbodiimide-based crosslinker. Results: The results of immunecytochemistry and PCR experiments confirmed the adipose-derived stem cells (ASC) in differentiation to the keratinocytes under the treatment of keratinocyte growth factor. The isolated ASC were seeded on the scaffolds and implanted at the prepared wounds. The scaffolds without cells were considered as a control and implanted on the other side of the rat. Histopathological analyses confirmed the formation of new tissue on the scaffold-cell side after 14 days with the formation of dermis and epidermis. Conclusion: These results indicated the capacity of ASC in differentiation to keratinocytes and also wound healing in vivo. Key Words: Tissue engineering, Keratinocytes, Mesenchymal stem cells  相似文献   
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