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31.
A survey of 103 family dairy farms in Galicia (N.W. Spain) collected information on 94 variables (78 quantitative, 16 qualitative) belonging to seven groups dealing with the location of the farm, family structure, sources of income, production variables, characteristics of the farm house (‘housing quality’), characteristics of the complex comprising farm house and farm buildings (the ‘central area’), and the characteristics and proximity to the farm house of the routes used for transit of cattle, fodder, slurry, etc. Following elimination of redundant variables, principal components analysis identified four factors accounting for about 40% of the total variance: three dominated each by a single a priori group (house–farm separation, central area, and housing quality), and one (production capacity) that combined production and source-of-income variables. Using these factors, the farms studied were subjected to hierarchical clustering by means of the Ward aggregation strategy, and a typology was established accordingly. Finally, guidelines for the design and improvement of farm installations and housing on Galician family dairy farms are sketched. 相似文献
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Vieira Aline Bomfim Restrepo Mariana Alvarez Auzenne Danielle Molina Kevin O’Sullivan Meghan Machado Marcus Vinicius Cavanaugh Sarah Marie 《Veterinary research communications》2022,46(2):527-535
Veterinary Research Communications - Obesity is considered the most common nutritional disease of dogs. Even though overt obesity is more likely to impair health, even moderately overweight dogs... 相似文献
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Male camel infertility is a heterogeneous disorder. A variety of factors may adversely affect sperm production and function and impair fertility. This study was designed to evaluate the sensitivity and specificity of ultrasonography and testicular biopsy in the evaluation of the breeding soundness of male dromedaries compared with results obtained by clinical examination and semen analysis. Eighty‐four male dromedary camels (5–15 years old) were used in this study during the rutting season (November–May). Four sexually mature male camels were used as controls. These animals were apparently healthy and had histories of normal fertility. Eighty infertile male camels were subjected to an algorithmic approach based on information collected during careful examinations of the camels' breeding histories, clinical examinations, testicular evaluations, testicular ultrasonographies, the results of the semen analyses and testicular biopsies to diagnose the camels' infertilities. The differences in the semen parameters between the control and infertile male camels were highly significant (p < 0.01). Regarding the diagnoses of male camel infertility, the results of testicular ultrasonographies and biopsies were compared with those from the semen analyses, and the accuracies of these tests were 92.5% and 90%, respectively. Additionally, the results of the testicular ultrasonographies were matched with those of the testicular biopsies of the infertile animals, and this comparison resulted in 85% accuracy. Testicular biopsy is a promising method that, along with a carefully performed history, clinical examination, an appropriate testicular ultrasonography procedure and semen analysis, can afford veterinarians the opportunity for more precise diagnosis and treatment of many dromedary infertility disorders. 相似文献
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Three species of myxobolid parasites were found infecting the gills of the Iberian nase, Chondrostoma polylepis , in the River Ulla (Galicia, NW Spain), Myxobolus leuciscini , M. impressus and M. gallaicus sp. nov., which is described herein. Myxobolus leuciscini locates in the intralamellar space and the plasmodium begins to develop in the endothelium of the capillaries of the secondary lamellae. Myxobolus impressus plasmodia are located in the interlamellar multilayered epithelium. Myxobolus gallaicus plasmodia are elongated and are located exclusively in the central venous sinus of the branchial filament, suggesting that they begin their development in branchial endothelial tissue. We also present data on spore size and morphology, plasmodium and pansporoblast characteristics and pathological effects of the three species in the host branchial tissues. 相似文献
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Effects of different variable sets on the potential distribution of fish species in the Amazon Basin
Facundo Alvarez Pedro Gerhard Daniel Paiva Silva Bruno Spacek Godoy Luciano Fogaça de Assis Montag 《Ecology of Freshwater Fish》2020,29(4):764-778
Estimating species’ potential distribution is one of the main objectives of macroecology, especially when sampling biases can affect knowledge on how environmental variables affect species distribution. Ecological niche models estimate species’ environmental niches from different variables and their occurrences. Using the presence-only data from eight Amazonian fish species, which inhabit rivers and streams, we aimed to (a) explore the effect of different sets variables on the spatial distributions of target species and (b) evaluate the predictive responses of MaxEnt to sets of variables with different degrees of complexity. MaxEnt has high flexibility in relation to the input data and its performance is influenced by a moderate number of adjustable parameters, allowing for high precision results when balancing underestimation and overestimation errors. We used environmental predictors in MaxEnt the principal components of climatic, topographic and edaphic variables as inputs. The combination of topographic and edaphic variables produced more precise and spatially restricted distribution ranges for all species when compared to those generated with climatic variables. All models reached high AUC values, especially for stream species. Modelled range sizes were broader for the river species, suggesting different tolerance thresholds and habitat preferences when compared to stream species. The complexity of the different variables sets did not affect MaxEnt's prediction capacity. However, for stream species, MaxEnt showed a greater predictive power. This work increases the knowledge with regards to the influence of different environmental predictors on the spatial patterns of the distribution of Amazonian fish. 相似文献
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FASTING-INDUCED CHANGES TO THE PHARMACOKINETIC BEHAVIOUR OF ALBENDAZOLE AND ITS METABOLITES IN CALVES 总被引:4,自引:0,他引:4
S.F. SÁnchez L.I. Alvarez & C.E. Lanusse 《Journal of veterinary pharmacology and therapeutics》1997,20(1):38-47
The influence of fasting on the bioavailability and disposition kinetics of albendazole (ABZ) and its metabolites in cattle was investigated. ABZ (10 mg/kg) was given by intraruminal (i.r.) (Experiment 1) and intravenous (i.v.) (Experiment 2) administration to Holstein calves either fed ad libitum (control) or subjected to a 48 h fasting period (fasted group) prior to treatment. The rate of passage of digesta through the gastrointestinal (GI) tract was evaluated by measurement of cobalt faecal excretion following the oral administration of the sodium-cobalt-ethylendiamine-tetracetic acid complex to calves subjected to the feeding conditions above described. Jugular blood and abomasal fluid (via cannula) samples were collected over 120 h post-treatment; samples were analysed by high performance liquid chromatography (HPLC) for ABZ, ABZ sulphoxide (ABZSO) and ABZ sulphone (ABZSO2). Fasting the animals prior to the i.r. treatment resulted in pronounced modifications to the plasma and abomasal fluid disposition kinetics of ABZ and its metabolites. A greater extent of GI absorption with significantly higher Cmax (150%) and AUC (310%) values for ABZSO in plasma, was observed in fasted compared to fed animals following the i.r. administration of ABZ. Extended detection of ABZ metabolites resulting in significantly longer plasma t½el and MRT was also obtained in fasted compared to fed calves. These results correlated with the substantially enhanced availability of ABZ and its metabolites (AUCs over 200% greater) in the abomasal fluid of the fasted animals. Fasting did not induce changes to the plasma disposition of either ABZ or its metabolites after the i.v. treatment. The digesta passage rate, measured by the amount of cobalt excreted in faeces, was significantly lower in fasted compared to animals fed ad libitum. A delayed GI transit time that decreases the rate of passage of the drug down the digestive tract, may have accounted for enhanced ABZ dissolution and absorption in fasted compared to fed calves. The findings reported in this article show that fasting prior to treatment notably affects the bioavailability and disposition kinetics of ABZ and its metabolites in cattle. 相似文献
40.
J H Gould S C Hight G H Alvarez C E Nelson S G Capar 《Journal of the Association of Official Analytical Chemists》1990,73(3):401-404
Use of lead glazes on ceramicware and the release of lead from finished glazes are reviewed. Single units of ceramicware with initial lead leach levels from less than 0.1 to 470 micrograms/mL were subjected to multiple automatic dishwashings with intermediate scrubbing of the ware by plastic fiber pads. Ware was periodically leached with 4% acetic acid solution at room temperature for 24 h, and the solutions were analyzed for lead. Release of lead under these conditions is discussed. Results indicated that neither passive leachings nor multiple dishwashings and scrubbings can predict future lead-release characteristics of glazes and decorations. 相似文献