Testing the equi-resistance principle of the xylem transport system in a small ash tree: empirical support from anatomical analyses     

Bettiati D  Petit G  Anfodillo T 《Tree physiology》2012,32(2):171-177

In plants, water flows from roots to leaves through a complex network of xylem conduits. The xylem architecture is characterized by the conduit enlargement towards the stem base and the multiplication of conduits near the apices of lateral branches. The xylem architecture of a small ash tree was analysed by measuring the vessel hydraulic diameter (Dh) and number (N) at different heights along the stem and branches. Along the stem, Dh and N increased from the apex to the point of crown insertion. Below, Dh and N decreased and remained constant, respectively. In branches, the Dh and N of apices increased with distance from the ground (PL) (P < 0.001 and P < 0.0001, respectively), indicating that apical resistance (R(APEX)) becomes lower in the most peripheral branches (P < 0.0001). At the level of branch nodes along the stem, the total conductive area (AC) of the stem and branches just above the node was 11% higher than that of the stem just below the node (P = 0.024), whereas the conductivity (Kh) remained invariant above and below (P = 0.76). The difference in AC (ΔAC) between the branches and stem above each node increased with the distance of the node position from the stem apex (L). The xylem architecture of the analysed tree was characterized by anatomical modifications likely aimed at equilibrating the different path length effects on the hydraulic resistance of the different branches. Conduit tapering and multiplication seem to play a crucial role for the achievement of equal hydraulic resistance of all the leaves in the crown.  相似文献   

Development of microsatellite markers and evaluation of genetic diversity of the Amazonian ornamental fish Pterophyllum scalare     

Pandolfi  Victor César Freitas  Yamachita  Andrei Lincoln  de Souza  Felipe Pinheiro  de Godoy  Sara Mataroli  de Lima  Ed Christian Suzuki  Feliciano  Daniele Cassiano  de Pádua Pereira  Ulisses  Povh  Jayme Aparecido  Ayres  Denise Rocha  Bignardi  Annaiza Braga  Penafort  Jefferson Murici  de Fátima Ruas  Claudete  Lopera-Barrero  Nelson Mauricio 《Aquaculture International》2021,29(6):2435-2449

The objective of the present work was to develop species-specific microsatellite markers for P. scalare and to analyze the diversity and genetic structure of a wild population, from the Amazon River, and three commercial stocks (common, marble, and clown morphological variants), from farmers in Vieras-Minas Gerais. Through microsatellite-enriched genetic libraries, 11 microsatellite markers with adequate amplification patterns were characterized. Population genetic analysis identified eight polymorphic loci that generated 66 alleles ranging from two alleles (PSCA1B3) to nine (PSCA2H1). The polymorphic information content ranged from 0.031 to 0.827. High genetic differentiation was observed between the wild population and the stocks, and moderate differentiation between the three stocks. Deviation in the Hardy-Weinberg equilibrium was observed in one locus in the wild population, in five loci in the common morphological variant, in two in the marble, and in two in the clown morphological variant. Bayesian analysis of genetic structure revealed the existence of two clusters, one represented by the natural population and the other by the stocks. The developed microsatellite markers serve as a tool for the analysis of diversity and genetic structure and conservation studies of P. scalare.

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Effect of pretilachlor and fenclorim on carbohydrate and protein formation in relation to their persistence in rice     

Scarponi L  Del Buono D  Vischetti C 《Pest management science》2005,61(4):371-376

The persistence of pretilachlor applied to rice singly or in combination with the safener fenclorim was investigated in connection with starch, glucose and protein formation. The addition of fenclorim to pretilachlor did not reduce the accumulation of the latter, but reduced its persistence in rice shoots, while the presence of pretilachlor did not affect the persistence of fenclorim, but significantly increased its accumulation in the shoots. Therefore the safening effect of fenclorim consisted of a more rapid detoxification of pretilachlor. Over the period of pretilachlor and fenclorim detoxification, decreases in starch content, partially counterbalanced by increases of free glucose, and decreases in total protein content were observed in pretilachlor-treated shoots; decreases in both starch and free glucose, as well as in total protein content, were observed in fenclorim -treated shoots compared with the untreated controls. The decreases in starch and total glucose appeared to be a direct consequence of reduced glucokinase and ribulose-1,5-bisphosphate carboxylase activity, and the decrease in total protein an indirect consequence of reduced glutamine synthetase and glutamate synthase activity, in response to pretilachlor and fenclorim treatments.  相似文献   

Intake,digestibility, and growth performance of Girolando bulls supplemented on pasture in Bahia,Brazil     

Rocha  Wéder Jânsen B.  Silva  Robério R.  da Silva  Fabiano F.  de Carvalho  Gleidson G. P.  da Silva  Ana Paula G.  Silva  João Wilian D.  Paixão  Tarcísio R.  Freitas  Tiago B.  Mendes  Fabrício Bacelar L.  Barroso  Daniele S.  de Souza  Sinvaldo O.  Santos  Laize V. 《Tropical animal health and production》2019,51(6):1413-1420

Tropical Animal Health and Production - The objective of this trial was to evaluate intake, digestibility, and growth performance of Girolando bulls submitted to two nutritional planes while...  相似文献   

Implications of low fiber levels in finishing lambs on performance,health, rumen,and carcass parameters     

Gallo  Sarita Bonagurio  Brochado  Thais  Ariboni Brandi  Roberta  da Silva Bueno  Ives Cláudio  Passareli  Daniele  Birgel  Daniela Becker  Birgel Junior  Eduardo Harry 《Tropical animal health and production》2019,51(4):767-773

Tropical Animal Health and Production - The objective of this study was to evaluate the effects of different levels of NDF in high-concentrate diets on performance and aspects ruminal, blood, and...  相似文献   

Comparison of intranasal versus intravenous midazolam for management of status epilepticus in dogs: A multi‐center randomized parallel group clinical study     

Marios Charalambous  Holger A. Volk  Andrea Tipold  Johannes Erath  Enrice Huenerfauth  Antonella Gallucci  Gualtiero Gandini  Daisuke Hasegawa  Theresa Pancotto  John H. Rossmeisl  Simon Platt  Luisa De Risio  Joan R. Coates  Mihai Musteata  Federica Tirrito  Francesca Cozzi  Laura Porcarelli  Daniele Corlazzoli  Rodolfo Cappello  An Vanhaesebrouck  Bart J.G. Broeckx  Luc Van Ham  Sofie F.M. Bhatti 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(6):2709-2717

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Severe meningeal fibrinoid vasculitis associated with Theileria taurotragi infection in two short-horned Zebu cattle     

Elena Biasibetti  Chiara Sferra  Godelieve Lynen  Giuseppe Di Giulio  Daniele De Meneghi  Laura Tomassone  Federico Valenza  Maria Teresa Capucchio 《Tropical animal health and production》2016,48(6):1297-1299

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Ultrasound-guided retrieval of plant awns     

Daniele Della Santa  Federica Rossi  Fabio Carlucci  Massimo Vignoli  Patrick Kircher 《Veterinary radiology & ultrasound》2008,49(5):484-486

In dogs, surgical removal of plant awns causing a foreign body granuloma or abscess may be challenging. The inability to localize the foreign body during surgical removal often leads to abscess recurrence. In this report, we describe ultrasound-guided retrieval as an alternative to standard surgical retrieval in animals where the plant awn can be identified sonographically. This procedure was used in six dogs with a superficial abscess due to a plant awn, and in all dogs the foreign body was successfully retrieved with Hartmann forceps. No complication was observed and no abscess recurred. Minimally invasive ultrasound-guided plant awn retrieval appears to be a safe effective method of retrieving superficially located plant awns in the dog.  相似文献   

Relationship between metabolic bone disease and bone mineral density measured by dual-energy X-ray absorptiometry in the green iguana (Iguana iguana)     

Alessandro Zotti  DVM  PhD    Paolo Selleri  DVM    Paolo Carnier  Massimo Morgante  DVM    Daniele Bernardini  DVM 《Veterinary radiology & ultrasound》2004,45(1):10-16

The aim of our work was to study the feasibility of using dual-energy X-ray absorptiometry to obtain reference bone density values in relation to body weight, gender, and metabolic bone disease in the green iguana. The study was performed on 28 animals. The weight, age, and gender of each iguana were recorded. Each lizard was carefully examined and radiographed to detect signs of metabolic bone disease. Blood samples were collected from each animal to evaluate Ca/P and total protein. All animals, both affected (group B; n = 11) and unaffected (group A; n = 17) by metabolic bone disease, were individually scanned using an X-ray densitometer. The regions of interest were the head, lumbar spine, right, and left femur. Statistical analysis was performed separately for each region of interest. Body weight had the strongest relationship with bone density (P < 0.01). Within regions of interest, for iguanas of average weight (710 g), statistically significant differences between healthy and sick animals were found: head (0.140 vs. 0.090 g/cm2; P < 0.01); lumbar spine (0.164 vs. 0.107 g/cm2; P < 0.01); right femur (0.103 vs. 0.076 g/cm2; P < 0.01); left femur (0.103 vs. 0.078 g/cm2; P < 0.01). Regression equations to obtain reference values of bone density as a function of body weight for animals affected and not affected by metabolic bone disease are provided. Our data indicate that X-ray bone densitometry is an additional tool for studying bone pathophysiology in reptiles.  相似文献   

Testing an ecological model for transmission of Salmonella enterica in swine production ecosystems using genotyping data     

Weigel RM  Nucera D  Qiao B  Teferedegne B  Suh DK  Barber DA  Bahnson PB  Isaacson RE  White BA 《Preventive veterinary medicine》2007,81(4):274-289

An ecological model for transmission of Salmonella enterica in swine production ecosystems was developed, identifying host species, environmental reservoirs, and temporal, spatial, and functional (i.e., stage of production) dimensions. It was hypothesized that transmission was most likely within spatial and functional compartments, between hosts of the same species and abiotic compartments of the same type. Eighteen swine production systems in Illinois, USA, were sampled in four collection cycles (1998, 1999, 2000, 2003). There were 11,873 samples collected, including feces from swine and other mammals and birds, and samples from insects, pen floors, boots, feed, and water. The 460 Salmonella isolates obtained were genotyped using repetitive sequence PCR with three primers—REP, BOX, and ERIC. All isolates from 2000 and 2003 were serotyped, as well as a subsample from 1998 and 1998. Genetic relatedness was estimated from the similarity of fragmentation patterns after gel electrophoresis of PCR products. Cluster analysis identified genetically related isolates. Linking of isolates in tight clusters (similarity ≥85%) was viewed as evidence for transmission. Five farms had a sufficient number of tight clusters for hypothesis testing. The factors most differentiating isolates genetically were farm of origin and time of sampling. Isolates were also differentiated genetically by site, building, room, and pen. There was no consistent association of genotype with stage of production or host/environment reservoir. Serotype analysis confirmed that Salmonella lineages were differentiated by visit and site. Thus, Salmonella transmission was primarily over short distances, i.e., within the same pen or room, with some transmission between rooms and buildings on the same site, but with limited transmission between sites. Transmission was observed across a variety of ecological niches represented by different host species and environmental reservoirs. Genetic differences over time reflected multiple introductions into the ecosystem of different Salmonella genotypes, as well as evolutionary changes within lineages. Intervention strategies to reduce Salmonella prevalence within swine production ecosystems would be best targeted at maintaining spatial barriers to transmission, whereas intervention targeted at specific biological hosts or environmental reservoirs is less likely to be effective.  相似文献