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101.

Silvopastoral systems integrate the complexity of forestry and forage-livestock management in an economically and ecologically sustainable way. However, these systems have undergone intensive pressure over the past decades caused by changes in land uses, as well as, in local socioeconomic priorities that suppressed traditional practices such as livestock grazing. These changes have caused land cover spatiotemporal diversifications whose effects were investigated in a traditional oak silvopastoral system at western Greece. In order to investigate the effect of human activities over the study area, the spatiotemporal land cover changes in conjunction with human and animal population changes and the environmental factors altitude, soil depth, inclination and rock type were analyzed. Also, forest-crown density changes were examined as a complimentary factor for the investigation of human intervention in the study area. Data about land-cover changes were derived from aerial orthorectified photographs of years 1945 and 2008, complimented by maps of environmental factors. Data digitization was implemented by the use of ArcGis. Based on the data analysis it derives that land cover changes are mainly attributed to direct human intervention. Environmental factors affect the ecosystem in two ways; first by affecting the location, type and intensity of human activities in the area, for example, soil depth determines where land is more productive and so predetermines the location, type and intensity of agricultural activities. Secondly, in the areas without or with minimal human intervention, environmental factors affect directly the land cover in conjunction with natural species necessities and their antagonistic capabilities.

  相似文献   
102.
103.
1. An experiment was conducted to determine the individual and combined effects of two essential oils, oregano and garlic, on carcass characteristics, meat composition, colour, pH and sensory quality of broiler meat.

2. The diets were supplemented with no essential oil (control), oregano essential oil or garlic essential oil at 300 mg/kg and oregano essential oil at 150 mg/kg + garlic essential oil at 150 mg/kg.

3. Dietary oregano and garlic oil supplementation did not affect carcass yields, the relative weight of carcass parts, breast and thigh meat composition, pH or b* value of breast meat. Oregano + garlic oil supplementation significantly decreased the L* value. The a* value of breast meat in birds given a diet supplemented with oregano oil was lower than that in birds given a diet supplemented with garlic oil and oregano oil + garlic oil. The essential oil addition had no positive effect on the oxidative stability. There was no difference between the treatments in breast appearance.

4. The juiciness, flavour, oxidised flavour and acceptability of breast meat samples were affected by treatments.  相似文献   

104.
Veterinarians and veterinary technicians are at risk for occupational brucellosis. We described the risk factors of occupational brucellosis among veterinary personnel in Turkey. A multicenter retrospective survey was performed among veterinary personnel who were actively working in the field. Of 712 veterinary personnel, 84 (11.8%) had occupational brucellosis. The median number of years since graduation was 7 (interquartile ranges [IQR], 4–11) years in the occupational brucellosis group, whereas this number was 9 (IQR, 4–16) years in the non-brucellosis group (p < 0.001). In multivariable analysis, working in the private sector (odds ratio [OR], 2.8; 95% confidence interval [95% CI], 1.55–5.28, p = 0.001), being male (OR, 4.5; 95% CI, 1.05–18.84, p = 0.041), number of performed deliveries (OR, 1.01; 95% CI, 1.002–1.02, p = 0.014), and injury during Brucella vaccine administration (OR, 5.4; 95% CI, 3.16–9.3, p < 0.001) were found to be risk factors for occupational brucellosis. We suggest that all veterinary personnel should be trained on brucellosis and the importance of using personal protective equipment in order to avoid this infection.  相似文献   
105.
In this study, the arterial distributions of the aortic arches of three deer species (Axis axis, Ozotoceros bezoarticus and Mazama gouazoubira) were described. The animals were dissected immediately after being found dead. Latex injection method was used to observe the vascularization of the thorax. The branching pattern of the arteries of the thoracic aorta in O. bezoarticus was similar to domestic ruminants. In the M. gouazoubira and A. axis, there were no bicarotid trunk. Interestingly, the first branch of the brachiocephalic trunk was the left costocervical trunk in A. axis. Then, brachiocephalic trunk was divided into right and left subclavian arteries. M. gouazoubira and A. axis in contrast to O. bezoarticus were different when compared with other ruminants, and the absence of bicarotid trunk was more striking than previous reports.  相似文献   
106.

Background

Measurement of plasma concentration of natriuretic peptides (NPs) is suggested to be of value in diagnosis of cardiac disease in dogs, but many factors other than cardiac status may influence their concentrations. Dog breed potentially is 1 such factor.

Objective

To investigate breed variation in plasma concentrations of pro‐atrial natriuretic peptide 31‐67 (proANP 31‐67) and N‐terminal B‐type natriuretic peptide (NT‐proBNP) in healthy dogs.

Animals

535 healthy, privately owned dogs of 9 breeds were examined at 5 centers as part of the European Union (EU) LUPA project.

Methods

Absence of cardiovascular disease or other clinically relevant organ‐related or systemic disease was ensured by thorough clinical investigation. Plasma concentrations of proANP 31‐67 and NT‐proBNP were measured by commercially available ELISA assays.

Results

Overall significant breed differences were found in proANP 31‐67 (P < .0001) and NT‐proBNP (P < .0001) concentrations. Pair‐wise comparisons between breeds differed in approximately 50% of comparisons for proANP 31‐67 as well as NT‐proBNP concentrations, both when including all centers and within each center. Interquartile range was large for many breeds, especially for NT‐proBNP. Among included breeds, Labrador Retrievers and Newfoundlands had highest median NT‐proBNP concentrations with concentrations 3 times as high as those of Dachshunds. German Shepherds and Cavalier King Charles Spaniels had the highest median proANP 31‐67 concentrations, twice the median concentration in Doberman Pinschers.

Conclusions and Clinical Importance

Considerable interbreed variation in plasma NP concentrations was found in healthy dogs. Intrabreed variation was large in several breeds, especially for NT‐proBNP. Additional studies are needed to establish breed‐specific reference ranges.  相似文献   
107.
The differences in the ridge structure of the mandibles of different size Astacus leptodactylus (32–80 mm carapace length, CL) were investigated. The results showed that a modification occurs with an increase in size in the incisor ridge of mandibles in A. leptodactylus. The results also showed that A. leptodactylus possesses four different types of ridge structure in the mandibles. These are: (1) Incisor ridge with big teeth (dentate crenate), (2) Blade-like incisor ridge with numerous small teeth, (3) Blade-like ridge (toothless), (4) Blunt ridge. In conclusion, it is thought that the incisor ridge modification of the mandibles may cause the difference in the food choice of different size A. leptodactylus, because, crayfish possessing different ridge structures of the mandible may probably feed on different type of food.  相似文献   
108.
The stress response of grass carp to salinity was evaluated assessing the levels of hematocrit, leucocrit, plasma glucose, sodium, potassium and calcium. Mean hematocrit values increased following exposure to salinity. Mean leucocrit values elevated after exposure to salinity for 24 h, then decreased. Mean plasma glucose increased during saline exposure for 48 h and then decreased to normal values. Plasma sodium and chloride levels were increased to their highest values after 48 h. While plasma potassium value increased with the exposure time, plasma calcium values were not affected by salinity exposure.  相似文献   
109.
The activity and molecular forms of acetylcholinesterase (AChE, EC 3.1.1.7) were characterized in the brain, heart, white skeletal muscle and liver of the Siberian sturgeon (Acipenser baeri), European eel (Anguilla anguilla), wels (Silurus glanis), common carp (Cyprinus carpio) and silver carp (Hypophthalmichthys molitrix), belonging in four families. The brain had the highest (between 183.2±10.6 and 1361.2±189.7 mU mg-1 protein and between 4.7±0.4 and 23.5±2.7 U g-1 wet tissue) and the liver the lowest (between 25.3±1.9 and 126.5±22.7 mU mg-1 protein and between 1.0±0.1 and 4.5±0.5 U g-1 wet tissue) activity in all these fish, with the exception of the wels, where the heart contained the smallest amount of AChE (26.2±7.5 mU mg-1 protein and 1.2±0.3 U g-1 wet tissue). The highest tissue AChE activity was found in the carp and lowest in the sturgeon. The solubility properties and molecular forms of AChE in the four tissues were studied by extraction in high-salt medium (1.0 M NaCl) with and without the detergent Triton X-100 (0.5%, v/v). The proportions of detergent-soluble (DS) and salt-soluble (SS) forms of AChE varied considerably from one species to another, but a general tendency could be observed: the proportion of DS AChE was generally higher in the brain (between 70.4±4.1 and 82.5±1.2%) and lower in the heart (between 12.0±2.0 and 51.3±2.3%) and skeletal muscle (between 16.0±2.0 and 64.4±0.7%). Velocity sedimentation centrifugation revealed that most tissues contained the G4 or A4 form. Three tissues (brain, heart, and liver) of the Siberian sturgeon contained a relatively high proportion of the G1 form (between 24.3±2.4 and 28.6±4.9%), while the skeletal muscle of the wels contained only the most complex type of AChE, i.e., A12. Amongst the tissues studied, the brain and liver mostly contained amphiphilic globular forms of the G4 type, while the heart and skeletal muscle were rich in asymmetric forms (A4 and A12). It was concluded that the differences revealed in the activities of AChE and in the distribution of its molecular forms may be connected with the variation in behavioral habits (feeding and swimming patterns), and the developmental stage of the nervous system.  相似文献   
110.
广东南岭国家级自然保护区管理有效性与优先性研究   总被引:2,自引:1,他引:1  
应用广东省林业自然保护区有效管理评价框架,对广东南岭国家级自然保护区的管理有效性进行评分,计算其管理有效性指数值(ME)和管理优先性指数值(MP),并进行排序.结果表明,广东南岭国家级自然保护区的机构设置、管护设施、管理制度、经费管理、生态旅游、监督与评估的ME值均为1.00,其管理有效性最高;而宣传教育、权属、规划设计、科研监测和管理队伍的MP值均大于1.00,应优先加强管理.为此,该保护区的主要管理对策应包括打造南岭特色生态文化的实体和网络平台、构建利益协商、共享和监管的长效机制以及建设科研监测的新型台站.  相似文献   
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