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321.
Wongkaweewit K Prommachart P Raksasub R Buranaamnuay K Techakumphu M De Rensis F Tummaruk P 《Tropical animal health and production》2012,44(3):467-470
The aim of the present study was to evaluate the control of ovulation by the administration of human chorionic gonadotropin
(hCG) or gonadotropin-releasing hormone (GnRH) at the onset of estrus. Thirty-three multiparous sows housed under tropical
conditions and showing standing estrus within 5 days after weaning were included. The sows were allocated to three groups,
spontaneous ovulation (control group, n = 10), induced ovulation using 750 IU hCG (hCG group, n = 10), and induced ovulation using 50 μg GnRH (GnRH group, n = 13). The hormones were given at the onset of estrus and the occurrence of ovulation was monitored every 6 h by transrectal
ultrasonography. Data for weaning-to-estrus interval, onset of estrus-to-ovulation interval (EOI), and the length of estrus
were recorded. All sows in the control and hCG groups ovulated, while 3 out of 13 sows treated with GnRH developed cystic
ovaries (did not ovulate). Of those sows ovulating, the EOI of the hCG (40.2 ± 1.7 h) and GnRH (37.5 ± 3.3 h) groups were
shorter than that of the control group (63.6 ± 9.6 h; P < 0.05). In conclusion, the administration of either hCG or GnRH at the onset of estrus can control time of ovulation but,
at the dose employed, sows receiving GnRH may develop ovarian cysts. 相似文献
322.
Peletto S Zuccon F Pitti M Gobbi E Marco LD Caramelli M Masoero L Acutis PL 《Research in veterinary science》2012,92(1):147-150
Recently, atypical bovine pestiviruses (BVDV-3) have been identified in batches of contaminated foetal calf serum (FCS) and in naturally infected cattle. During routine screening of FCS by conventional panpestivirus PCR assay, one batch showed traces of pestivirus nucleic acids, and the contaminating virus was typed as BVDV-3-like. Phylogenetic analysis based on three genome regions (5'UTR, N(pro) and E2) showed that this strain, named IZSPLV_To, clusters in a separate clade with CH_KaHo/cont, a cell culture contaminant detected in Switzerland. This study is the first report of the detection in Italy of a FCS batch contaminated with BVDV-3 and adds more evidence that atypical pestiviruses represent a serious cause for concern in cell culture laboratories, with potential repercussions on BVD control and vaccine biosafety. Our findings suggest that the BE/B2 primers may be able to detect BVDV-3 in a panpestivirus assay, but testing of a larger number of strains is required. 相似文献
323.
Vilela VL Feitosa TF Braga FR de Araújo JV Souto DV Santos HE Silva GL Athayde AC 《Veterinary parasitology》2012,188(1-2):127-133
The aim of this study was to test a pellet formulation in a sodium alginate matrix of Duddingtonia flagrans in the biological control of goat gastrointestinal helminths kept in a native pasture in a semi-arid region of Paraíba state, northeastern Brazil. An area of 2.4 ha was divided into three paddocks, where groups of seven goats ware formed. Each group received the following treatments during the months of March to August 2011: D. flagrans group, received 3g of pellets containing D. flagrans (AC001) for each 10 kg/l.w., twice a week; Moxidectin 0.2% group, received 0.2mg/kg of Moxidectin 0.2% orally, every 30 days; Control group, received 3g of pellets without fungi per 10 kg/l.w., twice a week. Each month, a tracer goat was placed in each group for 30 days and then sacrificed and necropsied. The D. flagrans group showed a greater reduction in EPG, increased weight gain, higher rates of packed cell volume and lower parasitic load burden in the tracer goats compared to Moxidectin 0.2% and Control groups. D. flagrans was efficient in controlling goat gastrointestinal helminthiasis in a semi-arid region of northeastern Brazil. 相似文献
324.
325.
Mattia Brambilla Fabio Casale Valentina Bergero G. Matteo Crovetto Riccardo Falco Irene Negri Paolo Siccardi Giuseppe Bogliani 《Biological conservation》2009,142(10):2033-2042
Species conservation largely depends on knowledge of habitat needs of target species. GIS-models are increasingly used to assess habitat preferences and distribution of target species, but their accuracy is constrained by availability of digital data layers. We developed a two-steps approach aiming at showing pros and cons of landscape (GIS)- and site-level habitat models, identifying key habitat factors for conservation of a threatened bird species, the red-backed shrike Lanius collurio. A spatially explicit GIS-model was generated using landscape variables, and a second model at site level was developed using fine-scale variables measured on the ground. The GIS-based model was then extrapolated to the entire region to obtain a map of distribution of suitable habitats. Positive associations between shrike occurrence and both hedgerow length and partial shrub cover were detected at both scales. Shrikes were also positively associated with grassland cover at landscape level and with partial cover of untilled herbaceous vegetation at the finer scale, and negatively affected by lucerne cover. The GIS-model led to an affordable map of predicted habitat suitability which should help conservationists to focus on different local priorities, but was unable to identify effects of untilled and lucerne cover. Site-level model gave fine details for habitat management, but its application elsewhere requires ground-measurements of factors. Combining the multiscale models could indicate more urgent actions at large scales (e.g. maintaining suitable habitats, or improving connectivity among isolated patches) and draw a detailed figure of the most suitable habitat for the species. Shrike occurrence was associated with a higher number of shrub and tree species: the indicator value of the species should ensure general benefits for biodiversity from dedicated management. 相似文献
326.
Nardini A Gascó A Raimondo F Gortan E Lo Gullo MA Caruso T Salleo S 《Tree physiology》2006,26(9):1137-1144
We investigated the hydraulic architecture of young olive trees either self-rooted or grafted on rootstocks with contrasting size-controlling potential. Clones of Olea europea L. (Olive) cv 'Leccino' inducing vigorous scion growth (Leccino 'Minerva', LM) or scion dwarfing (Leccino 'Dwarf', LD) were studied in different scion/rootstock combinations (LD, LM, LD/LD, LM/LM, LD/LM and LM/LD). Shoots growing on LD root systems developed about 50% less leaf surface area than shoots growing on LM root systems. Root systems accounted for 60-70% of plant hydraulic resistance (R), whereas hydraulic resistance of the graft union was negligible. Hydraulic conductance (K = 1/R) of LD root systems was up to 2.5 times less than that of LM root systems. Total leaf surface area (A(L)) was closely and positively related to root hydraulic conductance so that whole-plant hydraulic conductance scaled by A(L) did not differ between experimental groups. Accordingly, maximum transpiration rate and minimum leaf water potential did not differ significantly among experimental groups. We conclude that reduced root hydraulic conductance may explain rootstock-induced dwarfing in olive. 相似文献
327.
Risk factors for overweight among Brazilian adolescents of low-income families: a case-control study
Silveira D Taddei JA Escrivão MA Oliveira FL Ancona-Lopez F 《Public health nutrition》2006,9(4):421-428
OBJECTIVE: To study risk factors for overweight among Brazilian adolescents of low-income families. DESIGN: Case-control study of obese and non-obese adolescents. SETTING: Anthropometric survey including 1420 students (aged 14-19 years) attending a public high school in S?o Paulo, Brazil. METHODS: Selection of 83 overweight (body mass index (BMI) >85th percentile) and 89 non-overweight (BMI >5th percentile and <85th percentile) subjects, frequency-matched by age, gender, pubertal development and socio-economic status. Among the nutritional, familial and behavioural data available, five covariates (parents' obesity, adolescents' past obesity, to have a best friend, dietary restriction and habit of napping) were included in the fitted hierarchical conditional logistic regression models. MEASUREMENTS: Parents or guardians and adolescents were weighed, measured and answered a pre-tested questionnaire applied by trained nutritionists and paediatricians. RESULTS: The prevalence of overweight was 15.2%. As previous risks, obese parents and obesity during infancy presented odds ratios (OR) and 95% confidence intervals (CI) of 2.23 (1.15-4.35) and 3.60 (1.47-8.80), respectively. As concurrent factors, the habit of napping, to have a best friend and reported dietary restriction presented OR (95% CI) of 3.43 (1.32-8.92), 5.15 (1.76-15.07) and 7.26 (2.95-17.88), respectively. Dietary patterns, frequency of obesogenic foods and other physical activity indicators presented no statistical significance. CONCLUSION: In case-control studies, OR may overestimate the true risks. Parents' obesity and previous childhood obesity were identified as risk factors; therefore these factors should be the target for preventive programmes and policies in order to prevent the burden of obesity in the near future. 相似文献
328.
Feeding,body condition and reproductive investment of Astyanax intermedius (Characiformes,Characidae) in relation to rainfall and temperature in a Brazilian Atlantic Forest stream
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Ursulla P. Souza Fabio C. Ferreira Francisco M. de S. Braga Kirk O. Winemiller 《Ecology of Freshwater Fish》2015,24(1):123-132
Life history theory seeks to explain how environmental variation selects for patterns of investment in growth and survival relative to production and survival of offspring. Seasonal variations in rainfall and temperature provide environmental cues for spawning by many tropical freshwater fishes. To investigate environment–life history associations, we conducted a one‐year study of Astyanax intermedius in an Atlantic Forest stream of southeastern Brazil. Our analysis focused on temporal variation in feeding, body condition and reproduction in relation to rainfall and water temperature. For mature females, food intake was not significantly correlated with rainfall or temperature; however, body condition was negatively correlated with rainfall and water temperature. Female reproductive effort was positively correlated with water temperature, but did not vary with rainfall. For males and juveniles, there was no significant relationship between food intake or body condition and either environmental variable. Testis weight was negatively correlated with rainfall, but was not significantly correlated with water temperature. We detected a negative correlation between gonad mass with body condition and food intake for females but not for males. Our results differed from other studies in tropical and subtropical areas where rainfall has been shown to be positively correlated with fish reproductive effort. Our results indicate that reproductive effort of males is relatively constant throughout the year, whereas for females, it increases with increasing water temperature. This increase in reproductive investment in concert with an increasing temperature and metabolic rate may incur a trade‐off with somatic growth and survival for this small stream fish. 相似文献
329.
Braguglia Camilla Maria Marani Dario Mininni Giuseppe Mescia Paolo Bemporad Edoardo Carassiti Fabio 《Water, air, and soil pollution》2004,158(1):193-205
The Italian Water Research Institute (IRSA) carried out sludge incineration tests on a demonstrative plant equipped with a circulating fluidized bed furnace. Aim of this paper is to present the potential applicability of non-conventional techniques for solid residues characterization. Results of five tests performed under different operating conditions are discussed. Incineration solid residues were sampled from the cyclone, downstream the furnace (cyclone ash, CA), and from the bag filter (filter ash, FA). Different techniques were used by the Mechanical and Industrial Engineering Department of the Roma TRE University, which cooperated with IRSA in the research project, to characterize incineration products and to correlate with process parameters. The X-ray Diffraction (XRD) technique was used to estimate the amount of sand, lost from the furnace, in CA and FA samples. Particle size distribution was measured using Low Angle Laser Light Scattering (LALLS). Scanning Electron Microscopy associated with Energy Dispersive Spectroscopy (SEM/EDS) was used to correlate size and shape of individual particles with chemical composition.This multifaceted approach to characterize incineration residues appears promising, providing additional and complementary information to the traditional chemical characterization. 相似文献
330.
Núñez Sellés AJ Vélez Castro HT Agüero-Agüero J González-González J Naddeo F De Simone F Rastrelli L 《Journal of agricultural and food chemistry》2002,50(4):762-766
An aqueous decoction of mango (Mangifera indica L.) stem bark has been developed in Cuba on an industrial scale to be used as a nutritional supplement, cosmetic, and phytomedicine. Previously we reported its antioxidant activity, and we concluded that the product could be useful to prevent the production of reactive oxygen species and oxidative tissue damage in vivo. A phytochemical investigation of mango stem bark extract has led to the isolation of seven phenolic constituents: gallic acid, 3,4-dihydroxy benzoic acid, gallic acid methyl ester, gallic acid propyl ester, mangiferin, (+)-catechin, (-)-epicatechin, and benzoic acid and benzoic acid propyl ester. All structures were elucidated by ES-MS and NMR spectroscopic methods. Quantitative analysis of the compounds has been performed by HPLC, and mangiferin was found to be the predominant component. Total polyphenols were assayed also by the Folin-Ciocalteu method. The free sugars and polyols content was also determined by GC-MS. 相似文献