bluuebunny/crossref_metadata_2025 huggingface dataset:
Microbial succession of glycogen accumulating organisms in an anaerobic-aerobic membrane bioreactor with no phosphorus removal
Authors: Wong M.-T. , Liu W.-T.
Published: July 2006

The succession of glycogen accumulating organisms (GAOs) has been observed in an acetate-fed, anaerobic-aerobic sequencing membrane bioreactor (MBR) operated for 260 days without enhanced biological phosphorus removal (EBPR) activity. Semi-quantitative fluorescence in situ hybridization results showed that a gammaproteobacterial lineage GB frequently observed in EBPR processes was initially the numerically dominant species (50–66% of total cells) of the GAO in the MBR from day 1 to day 38. During this period, succession of two different subgroups of group GB was also observed. On day 85 onward, a population shift from GB group to ‘Defluvicoccus’-related tetrad-forming organisms (TFO) occurred. This microbial succession was suspected to be related to the applied operating conditions (long hydraulic retention time and long solid residence time) which favored the proliferation of ‘Defluvicoccus’-related TFO rather than the GB group. Application of terminal restriction fragment length polymorphism on selected samples further revealed that the microbial diversity of the seeding sludge as determined by the number of terminal restriction fragments was higher than that of sludge samples taken after day 85.
The in situ physiology of Nostocoida limicola II, a filamentous bacterial morphotype in bulking activated sludge, using fluorescence in situ hybridization and microautoradiography
Authors: Seviour E.M. , Eales K. , Izzard L. , Beer M. , Carr E.L. , Seviour R.J.
Published: July 2006

The in situ physiology of the actinobacterial bulking and foaming filamentous bacterium “Nostocoida limicola” II was studied by fluorescence in situ hybridization/microautoradiography. Substrate assimilation patterns of pure cultures of this bacterium were different to those seen in activated sludge biomass samples. There was no evidence to suggest that “N. limicola” II preferred hydrophobic substrates, but evidence was produced to support the view that it is metabolically active under anaerobic conditions in activated sludge.
Specific SBR population behaviour as revealed by comparative dynamic simulation analysis of three full-scale municipal SBR wastewater treatment plants
Authors: Rönner-Holm S.G.E. , Mennerich A. , Holm N.C.
Published: July 2006

Three full-scale municipal sequential batch reactor (SBR) wastewater treatment plants (WWTPs) were investigated by dynamic simulation studies using ASM1.All three WWTPs showed similar kinetic and stoichiometric conditions in the SBR population behaviour after calibration of the models. The simulation results detected only a discrepancy to the ammonia online data during and shortly after shock loading under anoxic and anaerobic conditions that so far could not be adjusted by the ASM1 model. However, these differences did not severely affect the quality of the simulations nor the effluent flows. Additionally, in all cases a dynamic alpha factor curve occurred during the aeration phases that was verified by further oxygen transfer measurements. This might reveal new aspects for the process control, design and simulation of SBR WWTPs. A short lag phase was detected in many cases at the beginning of the first aeration phase.
Enrichment of activated sludge in a sequencing batch reactor for polyhydroxyalkanoate production
Authors: Majone M. , Beccari M. , Di Gregorio S. , Dionisi D. , Vallini G.
Published: July 2006

The paper describes the start up of a process for the production of polyhydroxyalkanoates (PHAs) from activated sludge. The excess sludge from a wastewater treatment plant was inoculated in a lab-scale sequencing batch reactor (SBR) to be enriched under aerobic conditions through intermittent feeding with a mixture of organic acids. Enriching of activated sludge was monitored through the measurement of polymer concentrations either in the mixed liquor or in the microbial biomass. The bacterial population dynamics during the SBR start up was followed through denaturing gradient gel electrophoresis and the main species present at the steady state were identified. All the measured parameters significantly changed in the SBR during first two weeks after the inoculum was seeded into the reactor, they then stabilized. At the steady state, the SBR produced 2.6 gVSS l−1 d−1, with a PHA content of 11% (on a COD basis). The enriched microbial biomass was then transferred into a batch reactor where the bacterial polymer content was increased through a new feeding. In the final batch stage, maximum storage rate and maximum polymer content in the biomass were 405 mgCOD gCOD−1 h−1 and 44% (on a COD basis), respectively. The PHA storage from the enriched microbial biomass was about 20 times faster and the PHA content was about 4 times higher than that of the inoculated activated sludge. Observations by fluorescence microscopy showed that the majority of microorganisms in the enriched biomass could be stored. Among the numerically most representative genera in the enriched biomass, Thauera, Candidatus Meganema perideroedes, and Flavobacterium were identified.
Description of filamentous bacteria present in industrial activated sludge WWTPs by conventional and molecular methods
Authors: Levantesi C. , Rossetti S. , Beimfohr C. , Thelen K. , Krooneman J. , van der Waarde J. , Tandoi V.
Published: July 2006

Conventional cultivation methods and molecular approaches were utilised to describe the filamentous bacterial population of industrial activated sludge WWTPs. In total 43 strains were isolated by micromanipulation and were affiliated with 12 different species, comprising two new species and a new genus. In particular, a new species of Microthrix, a new genus of a filamentous Alphaproteobacteria morphologically similar to Nostocoida limicola, and a new filamentous species closely related to the opportunistic pathogen Propionibacterium propionicum were obtained. Despite the high number of isolates, the cultivation approach was unable to describe the filamentous bacteria most common in industrial WWTP. A culture-independent approach, termed the cell sorting/RT-PCR method, was therefore applied to identify fastidious or non-culturable filamentous microrganisms from different industrial plants. By this method the relevant filaments were micromanipulated and their 16S rDNA genes were amplified by RT-PCR. This approach was highly efficient. In total 31 16S rRNA sequences were obtained and 16 of them were used for the design of new specific oligonucleotide probes that highlighted dominant filaments in industrial activated sludge plants.
Microbial community structure of activated sludge during aerobic granulation in an annular gap bioreactor
Authors: Williams J.C. , de los Reyes F.L.
Published: July 2006

A novel annular gap reactor was designed to create a controlled shear environment in which aerobic granular sludge could be developed. The bacterial and eukaryal community structures during two aerobic granular sludge experiments were tracked using denaturing gradient gel electrophoresis (DGGE). The first granule cultivation experiment, using an organic loading rate of 1.6 kg/m3d COD, resulted in biomass that was dominated by filamentous bacteria and Zoogloea ramigera colonies. A second experiment with a higher organic loading rate of 6 kg/m3d COD developed a granule-like morphology but was ultimately dominated by filamentous fungi. Species identification via DGGE band purification and DNA sequencing closely matched the observed sludge morphology and behavior.
Evaluation of the impacts of model-based operation of SBRs on activated sludge microbial community
Authors: Sin G. , Govoreanu R. , Boon N. , Schelstraete G. , Vanrolleghem P.A.
Published: July 2006

Impact of model-based operation of nutrient removing SBRs on the stability of activated sludge population was studied in this contribution. The optimal operation scenario found by the systematic model-based optimisation protocol of Sin et al. (Wat. Sci. Tech., 2004, 50(10), 97–105) was applied to a pilot-scale SBR and observed to considerably improve the nutrient removal efficiency in the system. Further, the process dynamics was observed to change under the optimal operation scenario, e.g. the nitrite route prevailed and also filamentous bulking was provoked in the SBR system. At the microbial community level as monitored by DGGE, a transient shift was observed to gradually take place parallel to the shift into the optimal operation scenario. This implies that the model-based optimisation of a nutrient removing SBR causes changes at the microbial community level. This opens future perspectives to incorporate the valuable information from the molecular monitoring of activated sludge into the model-based optimisation methodologies. In this way, it is expected that model-based optimisation approaches will better cover complex and dynamic aspects of activated sludge systems.
Towards exposure of elusive metabolic mixed-culture processes: the application of metaproteomic analyses to activated sludge
Authors: Wilmes P. , Bond P.L.
Published: July 2006

Protein expression is a direct reflection of specific microbial activities in any ecosystem. In order to assess protein expression in mixed microbial communities, the feasibility of applying proteomic techniques to activated sludge samples has recently been demonstrated. We report the application of metaproteomics to two activated sludges from a laboratory-scale sequencing batch reactor with dissimilar phosphorus removal performances. Fluorescence in situ hybridization (FISH) revealed that the sludge with good enhanced biological phosphorus removal performance (EBPR) was dominated by Betaproteobacteria (65% of EUBMIX binding cells) and gave positive signals for the Rhodocyclus-type PAO specific probe (59%). The non-EBPR sludge was dominated by tetrad-forming Alphaproteobacteria (75%). With regard to the proteomic investigation, 630 individual protein spots were matched across the replicate groups of the anaerobic and aerobic phases of the EBPR sludge with 9.4% of all spots being statistically different between the two phases. The non-EBPR metaproteomic maps exhibited 590 matched spots with 14.7% statistical differences between the two phases. Overall, the non-EBPR sludge expressed around 30% more significant differences than the EBPR sludge. The comparison of protein expression in the two sludges showed that their metaproteomes were substantially different and this was reflected in their microbial community structures and metabolic transformations.
Identity, abundance and physiology of Aquaspirillum-related filamentous bacteria in activated sludge
Authors: Thomsen T.R. , Kragelund C. , Nielsen P.H.
Published: July 2006

Microcolony-forming bacteria closely related to the genus Aquaspirillum in the Betaproteobacteria were recently observed to be abundant in many nutrient removal wastewater treatment plants. The developed oligonucleotide probe, Aqs997, however, occasionally also targeted some filamentous bacteria in activated sludge samples when fluorescence in situ hybridization was performed. In this study, the identity, abundance, and ecophysiology of these Aqs997-positive filamentous bacteria were studied in detail. Most of the Aqs997-positive filamentous bacteria could morphologically be identified as either Eikelboom Type 1701, Type 0041/0675 or possibly Type 1851, all characterized by epiphytic growth. They were found in almost all 21 wastewater treatment plants investigated. Two morphotypes were found. Type A filaments, which seemed to be the same genotype as the microcolony-forming bacteria targeted by probe Aqs997.Type B filaments also hybridized with probe GNS941, specific for the Chloroflexi phylum, so the true identity remains unclear. Aqs997-positive filaments usually stained Gram-negative, but Gram-positive filaments were also found, stressing the difficulties in identifying bacteria from morphology and simple staining results. Studies on the ecophysiology by microautoradiography showed that Aqs997-positive filamentous bacteria did not consume acetate and glucose, while some took up butyrate, mannose, and certain amino acids. Most likely, some Aqs997-positive filamentous bacteria were able to perform full denitrification such as the Aqs997-positive microcolony-forming bacteria, and some were able to store polyhydroxyalkanoates under anaerobic conditions, potentially being glycogen accumulating organisms.
Floc-forming properties of polyphosphate accumulating organisms in activated sludge
Authors: Larsen P. , Eriksen P.S. , Lou M.A. , Thomsen T.R. , Kong Y.H. , Nielsen J.L. , Nielsen P.H.
Published: July 2006

The physico-chemical characteristics of polyphosphate-accumulating organisms (PAO) involved in enhanced biological phosphorus removal (EBPR) was investigated in order to find a novel method for phosphorus recovery. If the physico-chemical characteristics of PAO are different from those of other main floc components, it may be possible to enrich PAO in bulk water or in the floc material for improved recovery of phosphorus. A combination of shear tests, chemical manipulation, and quantification of PAO by fluorescence in situ hybridization was applied. The microcolony strength of both Rhodocyclus-related PAO and Actinobacteria-related PAO was generally high as no treatment could break up more than 20% of all PAO in microcolonies. In contrast, it was possible to remove 20–40% of the organic matter and other bacterial cells by applying a high pH value or adding EDTA. With that a selective enrichment of PAO in the remaining floc material was possible. The feasibility of applying this selective PAO enrichment in flocs remains to be evaluated in full-scale plants for P-recovery.
Biological treatment of sludge digester liquids
Authors: van Loosdrecht M.C.M. , Salem S.
Published: July 2006

Nitrogen removal in side stream processes offers a good potential for upgrading wastewater treatment plants (WWTPs) that need to meet stricter effluent standards. Removing nutrients from these internal process flows significantly reduces the N-load to the main treatment plant. These internal flows mainly result from the sludge processing and have a high temperature and a high concentration of ammonia. Therefore, the required reactor volumes as well as the required aerobic SRT are small. Generally, biological treatment processes are more economical and preferred over physical–chemical processes. Recently, several biological treatment processes have been introduced for sludge water treatment. These processes are available now on the activated sludge market (e.g. SHARON®, ANAMMOX® and BABE® processes). The technologies differ in concept and in the limitations guiding the application of these processes for upgrading WWTPs. This paper reviews and compares different biological alternatives for nitrogen removal in side streams. The limitations for selecting a technology from the available ones in the activated sludge market are noted and analysed. It is stressed that the choice for a certain process is based on more aspects than pure process engineering arguments.
Hydrolysis and fermentation of activated sludge to enhance biological phosphorus removal
Authors: Vollertsen J. , Petersen G. , Borregaard V.R.
Published: July 2006

The conventional mainstream enhanced biological phosphorus removal (EBPR) process depends on the quality of the raw incoming wastewater. An alternative sidestream EBPR process is presented, where the substrates for storage by the polyphosphate accumulating organisms (PAOs) instead come from hydrolysis of the return activated sludge. This process is studied in full-scale at two treatment plants and quantified by means of phosphorus release rates and readily biodegradable COD (RBCOD) accumulation rates. It was seen that not only was a significant amount of RBCOD stored by PAOs but an approximately equal amount was accumulated in the sidestream hydrolysis tank and made available for the subsequent nitrogen removal process. The phosphorus release of the sludge with and without addition of different substrates was furthermore studied in laboratory scale. The study showed that the process is promising and in a number of cases will have significant advantages compared with the conventional mainstream EBPR design.
A novel process for organic acids and nutrient recovery from municipal wastewater sludge
Authors: Ahn Y.-H. , Speece R.E.
Published: July 2006

In this paper, a novel process for organic acids and nutrient recovery from municipal sludge was introduced and evaluated based on laboratory-scale studies. An economical estimation for its practical application was also performed by mass balance in a full-scale plant (Q = 158,000 m3 d−1). This novel process comprises an upflow sludge blanket-type high performance elutriated acid fermenter (5 d of SRT) for organic acids recovery followed by an upflow-type crystallisation (3 h of HRT) reactor using waste lime for nutrient recovery. In the system, the fermenter is characterised by thermophilic (55 °C) and alkaline conditions (pH 9), contributing to higher hydrolysis/acidogenesis (0.18 g VFACOD g−1 VSSCOD, 63.3% of VFACOD/COD produced, based on sludge characteristics of the rainy season) and pathogen-free stabilised sludge production. It also provides the optimal condition for the following crystallisation reactor. In the process, the waste lime, which is an industrial waste, can be used for pH control and cation (Ca and Mg) sources for crystallisation reaction. A cost estimation for full-scale application demonstrates that this process has economic benefits (about $67 per m3 of wastewater except for the energy expense) even in the rainy season.
Modelling and evaluation of nitrogen removal performance in subsurface flow and free water surface constructed wetlands
Authors: Tunçsiper B. , Ayaz S.Ç. , Akça L.
Published: July 2006

With the aim of protecting drinking water sources in rural regions, pilot-scale subsurface water flow (SSF) and free water surface flow (FWS) constructed wetland systems were evaluated for removal efficiencies of nitrogenous pollutants in tertiary stage treated wastewaters (effluent from the Paşaköy biological nutrient removal plant). Five different hydraulic application rates and emergent (Canna, Cyperus, Typhia sp., Phragmites sp., Juncus, Poaceae, Paspalum and Iris) and floating (Pistia, Salvina and Lemna) plant species were assayed. The average annual NH4-N, NO3-N and organic-N treatment efficiencies were 81, 40 and 74% in SSFs and 76, 59 and 75% in FWSs, respectively. Two types of the models (first-order plug flow and multiple regression) were tried to estimate the system performances. Nitrification, denitrification and ammonification rate constants (k20) values in SSF and FWS systems were 0.898 d−1 and 0.541 d−1, 0.486 d−1 and 0.502 d−1, 0.986 d−1 and 0.908, respectively. Results show that the first-order plug flow model clearly estimates slightly higher or lower values than observed when compared with the other model.
Potential of activated sludge disintegration
Authors: Boehler M. , Siegrist H.
Published: July 2006

The disposal of sewage sludge and the agricultural use of stabilised sludge are decreasing due to more stringent regulations in Europe. An increasing fraction of sewage sludge must therefore be dewatered, dried, incinerated and the ashes disposed of in landfills. These processes are cost-intensive and also lead to the loss of valuable phosphate resources incorporated in the sludge ash. The implementation of processes that could reduce excess sludge production and recycle phosphate is therefore recommended. Disintegration of biological sludge by mechanical, thermal and physical methods could significantly reduce excess sludge production, improve the settling properties of the sludge and reduce bulking and scumming. The solubilised COD could also improve denitrification if the treated sludge is recycled to the anoxic zone. However, disintegration partly inhibits and kills nitrifiers and could therefore shorten their effective solid retention time, thus reducing the safety of the nitrification. This paper discusses the potential of disintegration on sludge reduction, the operating stability of nitrification, the improvement of denitrification and also presents an energy and cost evaluation.
An innovative technology based on aerobic granular biomass for treating municipal and/or industrial wastewater with low environmental impact
Authors: Ramadori R. , Di Iaconi C. , Lopez A. , Passino R.
Published: July 2006

The paper reports the results of an investigation carried out at lab scale to assess the effectiveness of an innovative technology (SUPERBIO) for treating municipal and/or industrial wastewater. When this technology was applied for treating municipal wastewater, the results showed that even at maximum organic load (i.e. 7 kg COD m−3 d−1), the COD in the treated effluent was lower than 50 mg L−1. In addition, both ammonia and TKN removal efficiencies resulted in higher than 87% up to an organic load of 5.7 kg COD m−3 d−1 corresponding to a nitrogen load of 0.8 kg TKN m−3 d−1.

Very satisfactory process performances also resulted during tannery wastewater treatment, when a chemical oxidation step (i.e. ozonation) was inserted in the treatment cycle of SUPERBIO. In such an instance, at organic and nitrogen loadings of 3 kgCOD m−3 d−1and 0.20 kg N m−3 d−1, COD, NH+4-N and TSS average removals were 96, 99 and 98%, respectively. Finally, during the whole experimentation, SUPERBIO was always characterised by a very low sludge production. Such a result was ascribed mainly to the characteristics of biomass that grew in the form of very dense granules (i.e. 130 gVSS LBiomass−1) allowing a biomass concentration as high as 50–60 gTSS lbed−1 to be achieved.
Students' Learning Styles and Their Preferences for Online Instructional Methods
Authors: Butler Thomas J. , Pinto-Zipp Genevieve
Published: July 2006

In an attempt to serve online students' needs, several questions were asked: Is there a dominant learning style of students in online courses? Is there a preferred method of online instruction? Is there a relationship between learning styles and the preferred method of online instruction? A two-part survey was administered to all graduate students enrolled in SetonWorldWide. Part A consisted of the Gregorc Learning Styles Delineator (GSD) and Part B consisted of demographic questions and a Likert scale focusing on the rating of online instructional methods. Subjects ( N = 96) displayed varied learning styles with dual learning styles (56.2%) representing the largest group. Subjects demonstrated strong preferences for asynchronous log-ons (99%), a high degree of interaction within the course, and noted a high degree of satisfaction with their online programs (95%). Convenience was the most frequent reason reported (92%) for selecting a Web course. The strongest preferences were noted for instructional activities emphasizing convenience, time management, and interactivity. Correlation analysis between students' learning styles scores and six online instructional methods revealed several significant relationships which were inconsistent with personality traits. It was found that students enrolled in online education because of the convenience, displayed a dual learning style, and favored individual assignments and threaded discussions.
The Five-Factor Model of Personality and Smoking: A Meta-Analysis
Authors: Malouff John M. , Thorsteinsson Einar B. , Schutte Nicola S.
Published: July 2006

This article describes a meta-analysis of the relationship between the Five-Factor Model of personality and smoking. The results, based on nine studies and a total of 4,730 participants, show that smoking was associated with the following five-factor traits: low conscientiousness, low agreeableness, and high neuroticism. Smokers outside Canada and the United States had significantly higher extraversion than nonsmokers, while extraversion was not significantly related to smoking in Canada and the United States. The results, which for the first time quantified precisely through meta-analysis the association between the five-factor model of personality and smoking, provide support for the relevance of the Five-Factor Model to an important behavior and for the trait element of Gilbert's (1995) Situation-Trait-Adaptation-Response model of smoking. The results also suggest possible avenues for smoking prevention and treatment and for further smoking research.
Design-Oriented Introduction of Nanotechnology into the Electrical and Computer Engineering Curriculum
Authors: Kim Donghwi , Kamoua Ridha , Pacelli Andrea
Published: July 2006

Nanoelectronics has the potential, and is indeed expected, to revolutionize information technology by the use of the impressive characteristics of nanodevices such as carbon nanotube transistors, molecular diodes and transistors, etc. A great effort is being put into creating an introductory course in nanotechnology. However, practically all courses focus on the physics, chemistry, and materials science aspects of this discipline. On the other hand, a more abstract, design-oriented introduction is desirable for electrical and computer engineering majors. In order to teach design-oriented nanotechnology, the teaching curriculum must be extended to include new concepts. In particular, it is necessary to supply the design principles, device models, and software simulation tools. This article describes our approach for introducing nanotechnology system design into the Electrical and Computer Engineering undergraduate curriculum at Stony Brook University. The approach consists of developing a nanodevice library for SPICE-like simulator and a 3-week module on nanotechnology system design utilizing this library. The module will be woven into an existing course on Integrated Electronics.
Alcohol-Related Incident Guardianship and Undergraduate College Parties: Enhancing the Social Norms Marketing Approach
Authors: Gilbertson Troy A.
Published: July 2006

This randomized experiment examines the effects of contextual information on undergraduate college student's levels of alcohol-related incident guardianship at college parties. The research is conceptualized using routine activities theory and the theory of planned behavior. The experiment examines attitudinal variations about heavy drinking differentiated by sex, athletic status, and location of the drinking event. The sex and athletic status variables produce statistically effects on the dependent variables, while location of the drinking event is not significant. The article concludes by discussing the importance of context as it pertains to the social norms marketing strategy utilized in much college alcohol programming, and suggests a more directed marketing approach.
Clinical outcome of dogs with grade-II mast cell tumors treated with surgery alone: 55 cases (1996–1999)
Authors: Séguin Bernard , Leibman Nicole F. , Bregazzi Victoria S. , Ogilvie Gregory K. , Powers Barbara E. , Dernell William S. , Fettman Martin J. , Withrow Stephen J.
Published: July 2006

Objective—To determine outcome for dogs with grade-II mast cell tumors treated with surgery alone.

Design—Retrospective study.

Animals—55 dogs.

Procedures—Medical records were examined, and signalment; location and size of tumor; staging status; dates of local recurrence, metastasis, death, or last follow-up examination; status of surgical margins; previous surgery; postoperative complications; and cause of death were recorded. Follow-up information was obtained via reexamination or telephone conversations with owners or referring veterinarians. Univariate analysis was performed to identify prognostic factors.

Results—60 tumors in 55 dogs were included. Median follow-up time was 540 days. Three (5%) mast cell tumors recurred locally; median time to local recurrence was 62 days. Six (11%) dogs developed another mast cell tumor at a different cutaneous location; median time to a different location was 240 days. Three (5%) dogs developed metastases; median time to metastasis was 158 days. Fourteen dogs died; 3 deaths were related to mast cell tumor, and 7 were unrelated. The relationship with mast cell tumor was not known for 4. Median survival times were 151, 841, and 827 days, respectively, for these 3 groups. Forty-six (84%) dogs were free of mast cell tumors during the study period. A reliable prognostic factor could not be identified.

Conclusions and Clinical Relevance—Results suggest that additional local treatment may not be required after complete excision of grade-II mast cell tumors and that most dogs do not require systemic treatment. (J Am Vet Med Assoc2001;218:1120–1123)
Effect of hydroxyethyl starch infusion on colloid oncotic pressure in hypoproteinemic horses
Authors: Jones Peyton A. , Bain Fairfield T. , Byars T. Douglas , David J. Barry , Boston Raymond C.
Published: July 2006

Objective—To determine the effect of hydroxyethyl starch (HES) on colloid oncotic pressure (π) during fluid resuscitation of hypoproteinemic horses and to evaluate the clinical usefulness of direct and indirect methods for determination of π before and after infusion of a synthetic colloid.

Design—Prospective clinical study.

Animals—11 hypoproteinemic horses.

Procedure—Horses received IV infusions of 8 to 10 ml of a 6% solution of HES/kg (3.6 to 4.5 ml/lb) of body weight during fluid resuscitation. Blood samples were obtained for determination of plasma measured colloid oncotic pressure (πmeas) and plasma total protein and albumin (A) concentrations. Plasma globulin concentration (G) was calculated as the difference between plasma total protein and albumin concentrations. Calculated values for colloid oncotic pressure (πA + G) were determined by use of a predictive nomogram previously developed for horses.

Results—There was no significant difference between the means of πmeasand πA + Gat the beginning of HES infusion. After HES infusion, the mean of πmeaswas increased significantly from baseline for 6 hours. Mean plasma total protein and albumin concentrations and πA + Gwere decreased significantly from baseline for 24 hours. Differences between mean πmeasand πA + Gafter HES infusion were significant for 24 hours.

Conclusions and Clinical Relevance—There was good agreement between plasma πmeasand πA + Gin blood samples obtained from hypoproteinemic horses immediately before infusion of HES. Use of a predictive nomogram did not, however, account for the oncotic effect of HES. Results of comparison of πmeasto πA + Gafter HES infusion suggest that a significant oncotic effect was maintained for 24 hours in the study horses. (J Am Vet Med Assoc2001;218: 1130–1135)
Risk factors for and outcomes of noncatastrophic suspensory apparatus injury in Thoroughbred racehorses
Authors: Hill Ashley E. , Stover Susan M. , Gardner Ian A. , Kane Albert J. , Whitcomb Mary Beth , Emerson Alex G.
Published: July 2006

Objective—To evaluate effects of toe grabs, exercise intensity, and distance traveled as risk factors for subclinical to mild suspensory apparatus injury (SMSAI) in Thoroughbred racehorses and to compare incidence of severe musculoskeletal injury (MSI) in horses with and without SMSAI.

Design—Nested case-control study.

Animals—219 Thoroughbred racehorses racing or in race training.

Procedure—Racehorses were examined weekly for 90 days to determine incidence of suspensory ligament injury and monitor horseshoe characteristics. Every horse's exercise speeds and distances were recorded daily. Conditional logistic regression was used to compare exposure variables between incident case (n = 25) and selected control (125) horses. Survival analysis was used to compare time to MSI for horses with (n = 41) and without (76) SMSAI.

Results—The best-fitting logistic model for the data included age (< 5 vs ≥ 5 years old), toe grab height the week of injury (none vs very low, low, regular, or Quarter Horse height), and weekly distance the week preceding injury (miles). Although the 95% confidence intervals for all odds ratios included 1, the odds for SMSAI appeared to increase with the presence of a toe grab, higher weekly distance, and age ≥ 5 years. Horses that had SMSAI were significantly more likely to have a severe MSI or severe suspensory apparatus injury than were horses that did not.

Conclusions and Clinical Relevance—Results suggest that pre-existing SMSAI is associated with development of severe MSI and severe suspensory apparatus injury. Modifying training intensity and toe grab height for horses with SMSAI may decrease the incidence of severe MSI. (J Am Vet Med Assoc2001; 218:1136–1144)
Subchondral cystic lesions of the proximal extremity of the tibia in horses: 12 cases (1983–2000)
Authors: Textor Jamie A. , Nixon Alan J. , Lumsden Jonathan , Ducharme Normand G.
Published: July 2006

Objective—To determine clinical and radiographic features of subchondral cystic lesions (SCL) of the proximal extremity of the tibia in horses that could be used to classify these lesions as being related to osteochondrosis or osteoarthritis and to evaluate results of surgical debridement.

Design—Retrospective study.

Animals—12 horses with 14 SCL.

Procedure—Medical records and radiographs obtained before and after treatment were reviewed.

Results—In 6 young horses (8 lesions), SCL were considered to be related to osteochondrosis; all involved the lateral tibial condyle. The remaining 6 horses were mature and had radiographic evidence of osteoarthritis in addition to SCL. Arthroscopic debridement was performed in 4 horses in which lesions were considered to be a result of osteochondrosis and in 3 horses with osteoarthritis. Three horses in which SCL were considered to be a result of osteochondrosis performed athletically after debridement. Two horses with moderate osteoarthritis returned to work after arthroscopic debridement but at a lower level of athletic performance. One horse with SCL related to osteochondrosis responded to medical treatment and went on to race.

Conclusions and Clinical Relevance—Results suggest that arthroscopic debridement of SCL is feasible in horses in which lesions involve the cranial portion of the lateral or medial tibial condyle, and that treated horses may be able to perform athletically. (J Am Vet Med Assoc2001;218:408–413)
Risk factors for reduced postoperative fecal output in horses: 37 cases (1997–1998)
Authors: Little Dianne , Redding W. Rich , Blikslager Anthony T.
Published: July 2006

Objective—To determine prevalence and risk factors for development of ileus of the large intestine after surgery in horses, identified by reduced postoperative fecal output (RPFO).

Design—Retrospective study.

Animals—37 horses that developed RPFO after undergoing general anesthesia for reasons unrelated to the gastrointestinal tract.

Procedure—Fecal output was obtained from medical records as number of defecations per 24-hour period after surgery; RPFO was defined as ≤ 3 defecations per 24-hour period after surgery. The reference population included 48 horses that defecated ≥ 4 times during the same period. Demographic, clinical, and surgical variables were evaluated for their association with development of RPFO by use of logistic regression analysis.

Results—Ten (12%) horses, all of which had RPFO, developed signs of colic after surgery. Horses ≥ 5 years old that underwent orthopedic procedures of > 60 minutes’ duration and that did not receive phenylbutazone after surgery were at significant risk for developing RPFO.

Conclusions and Clinical Relevance—Results suggest that after surgery unrelated to the gastrointestinal tract in horses, there is an intermediate clinical phase characterized by reduced fecal output preceding overt signs of colic. Recognition of RPFO may reduce morbidity and mortality of such horses. (J Am Vet Med Assoc2001;218:414–420)
Influence of patient positioning on sensitivity of mesenteric portography for detecting an anomalous portosystemic blood vessel in dogs: 34 cases (1997–2000)
Authors: Scrivani Peter V. , Yeager Amy E. , Dykes Nathan L. , Scarlett Janet M.
Published: July 2006

Objective—To determine whether sensitivity of detecting an anomalous portosystemic blood vessel during operative mesenteric portography varied with patient positioning.

Design—Retrospective study.

Animals—34 dogs with a portosystemic shunt diagnosed via scintigraphy or surgery.

Procedure—Portograms were evaluated for a portosystemic blood vessel. Sensitivity was calculated from results obtained with dogs in left lateral, right lateral, and dorsal recumbency and from results obtained with dogs in 2 or 3 positions. Differences in sensitivity among positions and between 2 examiners were evaluated.

Results—Sensitivity was 85, 91, and 100% in dorsal, right lateral, and left lateral recumbency, respectively. Sensitivity was lower in dorsal recumbency than in left lateral recumbency, although differences were not significant. There was no significant difference between sensitivity of results obtained in dorsal and right lateral recumbency or right lateral and left lateral recumbency. Sensitivity for combined right lateral and dorsal positions was 97%, which was better than that in dorsal recumbency alone, although the difference was not significant. Because sensitivity in left lateral recumbency was 100%, there was no need to evaluate the improvement obtained by combining the result of this position with the results of other positions.

Conclusion and Clinical Relevance—Results of mesenteric portography varied with patient positioning. The optimal position varied among patients but left lateral recumbency may be better and dorsal recumbency worse. Sensitivity may be improved by performing the test with the patient in orthogonal recumbent positions. (J Am Vet Med Assoc2001; 219:1251–1253)
Association of serologic status for Neospora caninum and postweaning feed efficiency in beef steers
Authors: Barling Kerry S. , Lunt David K. , Snowden Karen F. , Thompson James A.
Published: July 2006

Objective—To determine the effects of serologic status forNeospora caninumonshort-term weight gain, feed intake, and feed efficiency (feed intake/gain).

Design—Longitudinal observational study.

Animals—34 weaned mixed-breed beef steers.

Procedure—Serologic status forN caninumwas determined for each steer on days 0 (weaning), 88, 116, 144, 172, and 200, using an agglutination test. Individual steer body weight was measured on days 0, 88, 116, 144, 172, 200, and 242 (slaughter). Daily feed intake was monitored from days 116 through 242. Serologic status was matched to animal performance for the period immediately following serum sample collection. A mixed mode, using repeatedmeasures with an unstructured covariance matrix, was used in the analysis. Breed, age, and pen effects were controlled for in the analysis.

Results—A reduction in average daily gain for the period following a positive serologic result was detected for the entire trial (6 measurements/steer). This may have been attributed to a significant impairment in feed efficiency rather than to an impairment in feed intake. Changes in serologic status in individual steers over time were common; additionally, the effects of serologic status on steer performance were also transitory.

Conclusions and Clinical Relevance—Significant reductions in short-term weight gain and feed efficiency were associated with the presence of antibodies againstN caninuminpostweaning beef steers. (J Am Vet Med Assoc2001;219:1259–1262)
Pharmacokinetics and pharmacodynamics of butorphanol in llamas after intravenous and intramuscular administration
Authors: Carroll Gwendolyn L. , Boothe Dawn M. , Hartsfield Sandee M. , Martinez Elizabeth A. , Spann Angela C. , Hernandez Adrian
Published: July 2006

Objective—To evaluate disposition of butorphanol after IV and IM administration, effects on physiologic variables, and analgesic efficacy after IM administration in llamas.

Design—Nonrandomized crossover study.

Animals—6 healthy adult male llamas.

Procedure—Butorphanol (0.1 mg/kg [0.045 mg/lb] of body weight) was administered IM first and IV 1 month later. Blood samples were collected intermittently for 24 hours after administration. Plasma butorphanol versus time curves were subjected to pharmacokinetic analysis. Two months later, butorphanol (0.1 mg/kg) was administered IM, and physiologic variables and analgesia were assessed.

Results—Extrapolated peak plasma concentrations after IV and IM administration were 94.8 ± 53.1 and 34.3 ± 11.6 ng/ml, respectively. Volume of distribution at steady state after IV administration was 0.822 ± 0.329 L/kg per minute and systemic clearance was 0.050 ± 0.014 L/kg per minute. Slope of the elimination phase was significantly different, and elimination half-life was significantly shorter after IV (15.9 ± 9.1 minutes) versus IM (66.8 ± 13.5 minutes) administration. Bioavailability was 110 ± 49% after IM administration. Heart rate decreased and rectal temperature increased. Somatic analgesia was increased for various periods. Two llamas became transiently sedated, and 2 became transiently excited after butorphanol administration.

Conclusions and Clinical Relevance—Although IV administration of butorphanol results in a short halflife that may limit its analgesic usefulness, the elimination half-life of butorphanol administered IM is likely to be clinically useful. The relationship among plasma butorphanol concentration, time, and analgesia differed with the somatic analgesia model; clinically useful analgesia may occur at lower plasma concentrations than those reported here. (J Am Vet Med Assoc2001;219:1263–1267)
Use of adult cat serum to correct failure of passive transfer in kittens
Authors: Levy Julie K. , Crawford P. Cynda , Collante Werner R. , Papich Mark G.
Published: July 2006

Objective—To evaluate the use of adult cat serum as an immunoglobulin supplement in kittens with failure of passive transfer.

Design—Randomized controlled study.

Animals—11 specific pathogen-free queens and their 43 kittens.

Procedure—Kittens were removed from the queens at birth, prior to suckling colostrum, and randomly assigned to 1 of 4 groups: colostrum-deprived, colostrum-fed, colostrum-deprived and administration of pooled adult cat serum IP, and colostrum-deprived and administration of pooled adult serum SC. Colostrum-fed kittens were returned to the queen and allowed to suckle normally. Colostrum-deprived kittens were isolated from the queen and fed a kitten milk replacer for 2 days to prevent absorption of colostral IgG. All colostrum-deprived kittens were returned to the queen on day 3. Serum IgG concentrations were measured by radial immunodiffusion in the kittens at birth and 2 days and 1, 2, 4, 6, and 8 weeks after birth.

Results—None of the kittens had detectable serum IgG at birth. Both IP and SC administration of adult cat serum resulted in peak serum IgG concentrations equivalent to those in kittens that suckled normally. Untreated colostrum-deprived kittens did not achieve serum IgG concentrations comparable to those for kittens in the other groups until 6 weeks of age.

Conclusions and Clinical Relevance—Results suggest that adult cat serum may be used as an immunoglobulin supplement in colostrum-deprived kittens. Although the minimum concentration of IgG necessary to protect kittens from infection is unknown, concentrations achieved were comparable to those in kittens that suckled normally. (J Am Vet Med Assoc2001;219:1401–1405)
Complications of enteroplication for the prevention of intussusception recurrence in dogs: 35 cases (1989–1999)
Authors: Applewhite Aric A. , Hawthorne Julia C. , Cornell Karen K.
Published: July 2006

Objective—To compare complication and recurrence rates in dogs treated for intussusception that underwent enteroplication to rates in dogs treated for intussusception that did not undergo enteroplication.

Design—Retrospective study.

Animals—35 dogs with intestinal intussusception.

Procedure—Information on signalment, clinical signs, potential predisposing causes, surgical technique, opioid administration, use of enteroplication, postoperative complications, and whether the intussusception recurred was obtained from the medical records.

Results—Dogs ranged from 8 weeks to 10 years old. Opioids were administered in the perioperative period in 34 dogs. Enteroplication was performed in 16 dogs. Complications of enteroplication that required a second surgery were identified in 3 dogs. None of the 16 dogs that underwent enteroplication had a recurrence of intussusception, whereas 1 of the 19 dogs that did not undergo enteroplication had a recurrence. Rate of intussusception recurrence and likelihood that a second surgical procedure would be required were not significantly different between dogs that underwent enteroplication and dogs that did not.

Conclusions and Clinical Relevance—Results suggest that enteroplication may be associated with lifethreatening complications in dogs, but the likelihood of a dog requiring a second surgical procedure following surgical correction of intussusception was not different between dogs that underwent enteroplication at the time of the initial surgery and dogs that did not. (J Am Vet Med Assoc2001;219:1415–1418)
Use of a polymerase chain reaction assay to detect infection with Eperythrozoon wenyoni in cattle
Authors: Vandervoort Jennifer M. , Bourne Candace , Carson Robert L. , Heath Allen M. , Boudreaux Mary K.
Published: July 2006

Objective—To determine whether a polymerase chain reaction (PCR) assay could be used to detectEperythrozoon wenyoniinthe blood of cattle.

Design—Prospective study.

Animals—95 cattle from various herds in Alabama and Georgia and 96 bulls enrolled in Auburn University's Alabama Beef Cattle Improvement Association Bull Test program.

Procedure—Blood samples were collected by means of venipuncture of the median caudal vein and submitted for a CBC and PCR assay. Blood smears were made immediately after blood collection and examined by means of light microscopy.

Results—Three of 95 cattle from herds in Alabama and Georgia and 5 of 96 bulls enrolled in the Bull Test program had positive PCR assay results. Organisms were seen in blood smears from only 5 of these 8 animals. Organisms were not seen in blood smears from any animals for which results of the PCR assay were negative.

Conclusions and Clinical Relevance—Results suggest that a PCR assay may be an effective method for detectingE wenyoniinfection in cattle and that the PCR assay may be a more sensitive test than evaluation of blood smears. (J Am Vet Med Assoc2001; 219:1432–1434)