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171.
Serum opsonization capacity, phagocytosis, and oxidative burst activity in neonatal foals in the intensive care unit 总被引:1,自引:0,他引:1
Gardner RB Nydam DV Luna JA Bicalho ML Matychak MB Flaminio MJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):797-805
BACKGROUND: Phagocytic activity of neonatal foals has been reported to be similar to that of adult horses, but serum opsonization capacity develops with age and may be further altered when opsonins are consumed during infection. HYPOTHESIS: Phagocytosis, oxidative burst activity, and serum opsonization capacity in neonatal foals admitted to an intensive care unit are reduced in comparison with control foals. ANIMALS: Blood samples were collected from hospitalized neonatal foals and from control foals. Hospitalized foals were characterized as sick or septic on the basis of a sepsis score and received intravenous plasma transfusion. METHODS: Phagocytosis, oxidative burst activity, and serum opsonization capacity were tested with flow cytometric analysis. Serum immunoglobulin and complement component 3 concentrations were determined with radial immunodiffusion. Serum amyloid A concentration was assayed with a commercially available solid-phase Sandwich ELISA Kit. Data were analyzed with nonparametric and regression methods. Alpha was set at P = .05. RESULTS: Phagocytic functions of septic and sick foals were lower than control foals in the initial phase of the study (P = .01). Opsonization capacity was significantly higher when bacteria were opsonized with serum from septic (P = .029) and sick (P = .006) foals than from control foals on day 1. Opsonization capacity in septic foals was comparable with control foals on days 2 and 5. This effect was not accompanied by an increase in serum complement C3 or immunoglobulin G concentrations independently. CONCLUSIONS AND CLINICAL IMPORTANCE: Our results suggest that phagocytic function could be decreased in hospitalized foals. The synergistic effect of opsonic elements provided by plasma transfusion may sustain opsonization capacity during sepsis. 相似文献
172.
Marcela de Almeida Contadini Fernanda Altieri Ferreira Rosana Ruegger Silva Corte Daniel Silva Antonelo Juan Fernando Morales Gómez Saulo da Luz e Silva 《Tropical animal health and production》2017,49(8):1709-1713
This study was carried out to evaluate the effects of chopped hay levels in high-concentrate diets with whole corn grain (WCG) on performance and carcass traits of finishing Nellore cattle. One hundred and eight 24-month-old Nellore intact males (453 ± 75 kg) were fed one of three WCG-based diets that differed in roughage level: without roughage (WCG), with 5% chopped hay included (WCG5), or with 12% chopped hay included (WCG12) in a block design (based on initial body weight) for 86 days. Animals fed WCG5 or WCG12 had significantly improved on final body weight, dry matter intake, average daily gain, feed efficiency, hot carcass weight, and dressing percentage when compared to those fed WCG. The Longissimus muscle area (P = 0.1108), backfat thickness (BFT; P = 0.6089), and rump fat thickness (P = 0.1798) were not affected by roughage levels. Therefore, using WCG diets without roughage negatively affects the performance of feedlot Nellore cattle but does not affect carcass traits and does lead to the minimum BFT required by the industry. 相似文献
173.
174.
Alexandre Pio Viana Fernando Higino de Lima e Silva Leonardo Siqueira Glória Rodrigo Moreira Ribeiro Willian Krause Marcela Santana Bastos Boechat 《Euphytica》2017,213(10):228
Sour passion fruit is an economically important tropical fruit crop with little explored genetic potential. This study aimed to provide breeders with essential estimates of genomic breeding values in economically important traits in passion fruit, using Bayesian models which may contribute to the implementation of Genomic Selection and develop new strategies for the continuity of sour passion fruit breeding programs. For this, the following Bayesian models were tested using 183 polymorphic marks: Bayesian Ridge regression, Bayes A, Bayes B, Bayes B2, Bayes Cπ and Bayesian Lasso for estimation of genomic breeding values. To achieve this, ninety-five full-sib progenies derived from the third cycle of recurrent selection of the sour passion fruit (Passiflora edulis Sims.) at Universidade Estadual do Norte Fluminense Darcy Ribeiro—UENF were used and eight fruit yield (number of fruit, total yield, mean fruit weight, fruit length, fruit width) and quality(percent pulp, skin thickness, soluble solids) traits were assessed. The Bayes Cπ (smaller deviance information criterion) yield the best genetic predictions for almost all traits. Genetic correlations in this study indicate that the number of fruit can be used as a proxy for yield. The values of genomic heritability obtained were high and ranged from 0.62 to 0.76 and predict accuracy ranged from 0.55 to 0.75, so we can to speculate that the use of two replicates in the present study was an adequate amount to obtain phenotypic mean, which was used to adjust the genomic prediction model. 相似文献
175.
A study was conducted to evaluate the aboveground biomass, nutrient content and the percentages of mycorrhizal colonization
in Eucalyptus camaldulensis and Eucalyptus grandis plantations in the semiarid region (15° 09′ S 43° 49′ W) in the north of the State of Minas Gerais in Brazil. Results show
that the total above-ground biomass (dry matter) was 33.6 Mg·ha−1 for E. camaldulensis and 53.1 Mg·ha−1 for E. grandis. The biomass of the stem wood, leaves, branches, and stem bark for E. camaldulensis accounted for 64.4%, 19.6%, 15.4%, and 0.6% of the total biomass, respectively (Table 2); meanwhile a similar partition of
the total above-ground biomass was also found for E. grandis. The dry matter of leaves and branches of E. camaldulensis accounted for 35% of total biomass, and the contents of N, P, K, Ca, Mg, and S in leaves and branches accounted for 15.5%,
0.7%, 12.3%, 22.6%, 1.9%, and 1.4% of those in total above-ground biomass, respectively. In the trunk (bark and wood), nutrient
accumulation in general was lower. Nutrient content of E. grandis presented little variation compared with that of E. camaldulensis. Wood localized in superior parts of trunk presented a higher concentration of P and bark contained significant amounts of
nutrients, especially in E. grandis. This indicated that leaving vegetal waste is of importance on the site in reducing the loss of tree productivity in this
semi-arid region. The two species showed mycotrophy. 相似文献
176.
177.
Simon J. Pierce Adriana Méndez‐Jiménez Kym Collins Marcela Rosero‐Caicedo Ara monadjem 《水产资源保护:海洋与淡水生态系统》2010,20(7):782-788
- 1. The whale shark (Rhincodon typus) is a popular focal species within the global marine tourism industry. Although this has contributed to increased protection being granted to the species in several countries, tourism itself can be detrimental to the sharks in the absence of appropriate management. Potential impacts can be mitigated, at least in the short term, by adherence to well‐designed interaction guidelines.
- 2. A burgeoning marine tourism industry based on swimming with whale sharks has developed at Tofo Beach in Mozambique. However, no formal management is currently in place at this site.
- 3. The behaviour of whale sharks during interactions with boats and swimmers were recorded during 137 commercial snorkelling trips run from Tofo Beach over a 20 month period. Whale sharks were encountered on 87% of trips, which operated year‐round.
- 4. Boat proximity and shark size were significant predictors of avoidance behaviour. No avoidance responses were recorded at >20 m boat distance.
- 5. The mean in‐water interaction time between sharks and swimmers was 8 min 48 s overall. There was a significant decrease in interaction times during encounters where sharks expressed avoidance behaviours, and also in cases where sharks had expressed boat avoidance behaviour before swimmers entered the water.
- 6. It is suggested that mean encounter times can be extended through adherence to a basic Code of Conduct for operators and swimmers that enforces minimum distances between the sharks, boats and swimmers. Using encounter time as a measure of the ‘success’ of interactions holds promise, as longer encounters appear to be indicative of lower impacts on sharks while also providing higher customer satisfaction for swimmers. Copyright © 2010 John Wiley & Sons, Ltd.
178.
Osorio A Martínez AM Schneider MI Díaz O Corrales JL Avilés MC Smagghe G Pineda S 《Pest management science》2008,64(10):1001-1007
BACKGROUND: Resistance to spinosad and methoxyfenozide has been studied in several insect pests, but there is a lack of information on Spodoptera exigua (Hübner) in Mexico. Therefore, evidence for the development of resistance in this pest to both compounds was examined. The effects of methoxyfenozide on reproductive parameters of S. exigua adults were also determined.RESULTS: Third instars from a field population were exposed for 24 h to the LC(50) of spinosad or methoxyfenozide for over six generations (G(2)-G(7)). No significant reduction in susceptibility to either compound was detected for up to five generations. In G(7), LC(50) values for insects exposed to spinosad and methoxyfenozide were respectively 2.75-fold and 1.25-fold greater than for G(1) larvae. Oral treatment with methoxyfenozide reduced the fecundity and fertility of G(7) adults, confirming sublethal effects on reproduction. Finally, five populations (Se-La Floriza, Se-Lazareto, Se-Bachigualato, Se-Los Agustinos and Se-Villa de Arista) of S. exigua were collected from fields in three states of Mexico for resistance monitoring to spinosad and methoxyfenozide. With the exception of Se-Villa de Arista, the other populations showed significant resistance to spinosad, with resistance ratios between 16- and 37-fold, compared with a susceptible laboratory colony. In contrast, only one population (Se-Lazareto) showed significant resistance to methoxyfenozide (13-fold).CONCLUSION: Resistance management programmes should be established, particularly in areas where S. exigua has developed resistance to spinosad. Copyright (c) 2008 Society of Chemical Industry. 相似文献
179.
Changes in the condition of broodstock, presence of larvae, and post-larval settlement of A. ater in Punta Arenas Cove (Antofagasta Region, Chile) were used to determine its reproductive cycle. The condition used as a spawning indicator shows that these events occur in three periods throughout the year (May–July, August–November, and December–February). Intense periods recorded in October–November and December–February coincided with periods in which the water temperature descended to less than 13 °C. Simultaneously, plankton samples indicated constant presence of A. ater larvae at this site, with large increases in abundance during August and between October and January, reaching a maximum of 2,192 larvae m?3 in October. The periods of increase in larval abundance coincide with spawning periods; however, the greatest abundances were recorded before the start of the descent of the spawning indicator of the population under study. Monthly installation and replacement of collectors, after recording the first spawning, showed the permanent settlement of A. ater post-larvae over the course of the study, with a period of greater intensity occurring from the end of August to the end of January, registering peaks in October and November with 5,667 and 4,183 post-larvae × 600 cm2 collector?1, months which also coincide with the greatest larval abundance. The presence of larvae and post-larvae of the mytilids Choromytilus chorus and Semimytilus algosus was also recorded alongside A. ater larvae and post-larvae. Ch. chorus presented a cycle very similar to that of A. ater in both stages, with a maximum abundance of 4,531 larvae m?3 in November and 13,533 post-larvae × 600 cm2 collector?1 in December. 相似文献
180.
David Juricka Jitka Novotna Jakub Houska Jana Parilkova Jan Hladky Vaclav Pecina Hana Cihlarova Marcela Burnog Jakub Elbl Zdena Rosicka Martin Brtnicky Jindrich Kynicky 《林业研究》2020,(1):197-208
The objective of this study is to investigate the potential causes of widespread Larix sibirica Ledeb.mortality observed in the Khentii massif of northern Mongolia.The ratio of deadwood to living trees in affected stands in the Goricho region,the southernmost study site situated close to the Gobi Desert,was as high as 3.6:1.Moisture fluctuations monitored over 2 years using electrical impedance spectrometry revealed that the Goricho study site had higher soil moisture levels than the two less affected sites Barun Bayan and Dzun Bayan.High soil moisture was recorded in an area characterized by highly skeletal soils,ones with more than 35%by volume of rock fragments,and comparatively shallow soil horizons,from valley to mountains.The layer of permafrost influencing hydrogeological processes is much deeper in the Goricho region compared to the undisturbed study sites.Redundancy analysis confirmed a significant number of dead L.sibirica on sites with developed soils.Live forest stands,however damaged,grow in this region on well-drained scree slopes or on rocky bastions.The mass mortality observed for L.sibirica may be directly linked to accelerated permafrost thaw in the area bordered by the Tuul and the Terelj Rivers.Our assumption is that L.sibirica root system necrosis occurred as a result of long-term waterlogging of developed soils with high spatial heterogeneity,normally able to absorb high quantities of groundwater.The areas unaffected were scree fields and rocky bastions characterized by adequate drainage.All of our findings support the primary stages of large-scale permafrost thaw,i.e.,correlating increases in soil moisture with increasing permafrost active layer thickness. 相似文献