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1.
Although the beta2 adrenergic agonists have been seen to have important effects on the mechanisms regulating the development and death of T-cells in the thymus, the side-effects on the immune system of anabolic treatments of these substances have hardly been considered. In order to evaluate the effects exerted by the beta2 adrenergic agonist clenbuterol on the thymocyte population, the thymus of eight pigs treated with anabolic doses of this substance was studied by morphometric methods, regarding apoptotic (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL)-positive) and normal (TUNEL-negative) cells. The thymus of another eight pigs fed without clenbuterol served as a control. The clenbuterol treatment had a clear effect on the thymocyte size, decreasing their mean nuclear area. The T-cell apoptosis index was also affected by the clenbuterol, significantly increasing the apoptosis percentage in the treated group with respect to the control. In the light of our results, the clenbuterol induced thymocyte apoptosis throughout the thymus and caused morphometric changes in the thymocyte population, which was in line with the immunosuppressive role attributed to other beta2 adrenergic agonists.  相似文献   
2.
Background: Hematology and serum biochemistry values can be useful for evaluating the health of populations of captive and free-living European brown hares ( Lepus europaeus ). However, current information is fragmented and incomplete.
Objective: The objective of this study was to determine normal hematology and serum chemistry values for a population of captive European brown hares and to investigate differences related to sex and age.
Methods: Routine hematology and serum chemistry values were determined for 48 captive European brown hares in Catalonia (northeastern Spain): 21 young (6 males and 15 females) and 27 adult (14 males and 13 females) hares. Blood was obtained by auricular venipuncture while animals were physically restrained. Results were expressed as the mean ± SD, and reference intervals were calculated as the mean ± 2SD.
Results: RBC count, PCV, concentrations of hemoglobin, total protein, albumin, gamma globulin, urea nitrogen, and creatinine, and alanine aminotransferase activity were significantly higher in adults than in young hares, and alkaline phosphatase activity and total bilirubin concentration were lower. Sex differences were not observed.
Conclusions: Hematology and serum chemistry results obtained in this study are considered representative for healthy captive European brown hares. A single reference interval can be used for values from male and female hares, however, age-specific intervals are needed for some analytes.  相似文献   
3.
This study aimed to provide the normal radiographic anatomic appearance of the limbs of the loggerhead sea turtle, Caretta caretta. Dorsopalmar and dorsoplantar radiographs were taken of the forelimbs and hindlimbs of 15 juvenile and 15 subadult loggerhead sea turtles, 17 alive and 13 dead. For comparison, computed tomographic, gross anatomic, osteologic, and histologic studies were performed on the limbs of 5 of the sea turtles. Bones from the distal part of the fore and hind flippers were seen in detail with a mammographic film-screen combination. The pectoral and pelvic girdles, superimposed by the carapace, were better seen on standard radiographs with the use of rare-earth intensifying screens. Mammographic radiographs of the manus of 5 small juvenile turtles showed active growth zones. Visualization of bone contours in the distal part of the limbs was clearer than in mammals owing to the very few superimpositions. The presence of a substantial amount of cartilage in the epiphyses produced better visibility of limb ends. We conclude that use of a mammography film-screen combination is the best way to evaluate the bony and joint structures of the limbs of sea turtles. Radiography provides reliable images for clinical purposes. Considering the low cost and logistics of this technique, it is a practical ancillary test for marine animal rehabilitation centers to use.  相似文献   
4.
The bursting of the mining dam of Aznalcollar (Seville, Spain) triggered an increase in the concentration of heavy metals in the soils of the river Guadiamar valley as a result of the leaching of the pyritic sludge deposited on them. After the cleaning operations which included, as well as mechanical clearing, the addition of different amendments, some areas with residual sludge remained, from which some heavy metals are being mobilized by the cyclical recharge and discharge processes of water in the profiles. This paper analyzes the effect of the soil recovery operations and the climatology on the concentration of metals and their distribution in the soil profile in an area affected by the toxic spill. Fourteen points have been selected in a plot in which acidity persists, there is no vegetation, and residual sludge stains can be seen at a glance. The temporal and spatial evolution of the extractable metals: Fe, Cu, Mn and Zn, the pH and the oxidable fraction has been measured in-depth. The results obtained up to now indicate a leaching of the pollutant towards deeper horizons, finding, at a depth of 757 cm, pH values of 3.5 and very high Fe and Mn concentrations available, especially in the profiles with large sized pores, with a big fraction of sand. On the surface, seasonally, there are low pH values of around 2.5 and extractable Fe contents of over 4000 ppm, which might have an influence on the quality of surface runoff or underground water.  相似文献   
5.
Dung beetles are considered keystone species because of their role in decomposition, seed dispersal, and control of vertebrate parasites in grazed habitats. Despite the ecological importance of this group to pasture ecosystem functioning, still little is known about its relationship with grazing management activities. We evaluated the conservation value of protected areas for dung beetle diversity by comparing two different management conditions of Mediterranean savanna in central Spain. Four different sites with wild herbivory (red deer, roe deer) were sampled inside the Cabañeros National Park, and four sites with traditional agrosilvopastoral management were sampled in a sheep farm near the park. The dung beetle species richness was similar between savanna conditions, but the total dung beetle abundance and biomass were considerably greater in the park grasslands than in the grasslands of the sheep farm. Dung beetle species composition, species dominance, and abundance by functional groups from both park and farm sites were different, despite the high similarity among the sampled sites in both hydric content and dung availability. Onthophagus maki (Illiger 1803) and O. furcatus (Fabricius 1781) were the dominant species in the park, while O. furcatus, Aphodius foetidus (Herbst 1783), and Caccobius schreberi L. were the dominant species on the farm. Species richness and abundance of telecoprids were higher in the park than on the farm. Abundance of paracoprids was also higher in the park than on the farm, while no differences in species richness and abundance of endocoprids were observed between both conditions. These results suggest that management activities such as plowing and the use of veterinary substances affect soil structure and dung quality and could be important factors that alter dung beetle assemblages in terms of composition, abundance, and biomass on traditional farms.  相似文献   
6.
Optimal management practices for nitrogen (N) fertilization is well defined for corn (Zea mays) cultivated during summer (“summer” corn), but not for corn cultivated during the fall (“fall” corn) in the tropics. Two experiments were carried out to evaluate N rates (50, 100, 200, and 300 kg N ha?1), N application timing (pre-planting – PP, V2–V3, and V5–V6) and N split application, once (at PP, V3, and V6), two (at V3+ V6) and three times (at PP+ V3+ V6) in corn cultivated during summer (2014/2015) and fall (2015/2016). Data on corn grain yield (CGY), weight of 1000-grains, leaf N content and values of soil-plant analyses development (SPAD) were collected and analyzed using univariate, multivariate (principal component analysis, PCA) and regression analysis. Results showed that corn growth was affected by N rates and splitting. Corn cultivated during summer presented higher CGY and weight-1000 g than corn cultivated during the fall. The highest yields were obtained with higher N rates on “summer” corn (125 kg N ha?1) than “fall” corn (50 kg N ha?1). Split N-application at vegetative growth stages, V3+ V6, or PP+ V2+ V6, provided higher yields for “summer” corn, while only PP application was a reliable period of N fertilization for “fall” corn. The finding is that corn cultivated during the fall presented a lower response to N and no obvious advantages to split N fertilization when compared to corn cultivated during summer. These optimal management practices for N fertilization in corn production in the tropics depend on soil water availability.  相似文献   
7.
This work investigates the use of electronic tongues for monitoring nutrient solution compositions in closed soilless systems. This is a horticultural technique in which the nutrient solution is continuously recirculated and an automatic recomposition system maintains the concentration of the different ions in the optimum range for the plants. Electronic tongues used in this study comprised an array of potentiometric sensors and complex data processing by artificial neural networks. A first experiment was able to carry out the simultaneous inline monitoring of ammonium, potassium, sodium, chloride, and nitrate ions during the winter. In the second and third applications, done during summer, some changes were introduced in the sensor array to improve its response toward chloride ions and to incorporate phosphate in the model. This electronic tongue was validated with real greenhouse samples and was also able to detect the variations in the ion concentrations caused by an incorrect configuration of the recomposition system.  相似文献   
8.
Tropical Animal Health and Production - The objective of this study was to evaluate the biochemical, behavioral, and physiological parameters in pregnant sows of native and improved crossbreeds...  相似文献   
9.
Here, we aimed to study the slow muscle of the fish Piaractus mesopotamicus submitted to 30 days of fasting (D30) followed by 1 day (D31) or 30 days of refeeding (D60). Histological analysis of fibre diameter was performed in D30 and D60. The gene expression of parvalbumin (pvalb), atrogenes (murf1a, murf1b, mafbx) and anabolic genes (igf‐1, mtor) was analysed using RT‐qPCR in D30, D31 and D60. The proteome was obtained by shotgun proteomics at D30 and D60, and the set of differentially expressed proteins was analysed by bioinformatics. In all experiments, the control was regularly fed fish. The histological analysis showed no changes in muscle fibre diameter. The expression of catabolic and anabolic genes was not changed, except for the downregulation of igf‐1 in D30 and of mafbx in D31. The expression of pvalb was not changed in D30 and D60 but was decreased in D31. The proteomic analysis identified 169 proteins in D30 (24 upregulated and 18 downregulated) and 170 proteins in D60 (17 upregulated and 21 downregulated); many of them were related to energetic metabolism and intracellular Ca2+ homoeostasis. Overall, our results indicate that the slow‐twitch muscle presented few changes upon prolonged fasting and refeeding condition.  相似文献   
10.
In this study, the aim was to establish a protocol for first feeding of diploid and triploid yellowtail tetra Astyanax altiparanae in laboratory conditions. The fry were fed with five different diets: (i) Artemia franciscana nauplii, (ii) plankton, (iii) dry food, (iv) Artemia franciscana nauplii + plankton, and (v) Artemia nauplii + plankton + dry food. Additionally, the growth and survival rates of diploid and triploid individuals were also evaluated. On day 10, the length of the fish between the treatments differed significantly (p = .0001) and ranged from 4.07 ± 0.06 mm (dry food) to 8.50 ± 0.64 mm (plankton + Artemia). The sizes of the fish increased with time, except for the fish fed with dry food. The survival rates were similar for the fish fed with the four diets and ranged from 80.7 ± 5.4% (dry food + plankton + Artemia to 92.0 ± 1.6% (plankton + Artemia), but differed from the fish fed with dry food (17.7 ± 5.8%, p = .0017). Diploids and triploids did not present differences on day 0 (p = .2252) and on day 10 (p = .4844) when the fish presented 6.77 ± 0.25 mm and 6.54 ± 0.15 mm respectively. Survival of diploids (87.3 ± 5.13%) and triploids (74.67 ± 2.30%) were also similar (p = .0285). These data are innovative and useful for establishing protocols for this species in both academic and applied sciences.  相似文献   
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