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1.
J Anim Sci ; 1012023 Jan 03.
Article in English | MEDLINE | ID: mdl-37950347

ABSTRACT

Processing conditions, particularly temperature and duration of heating, impact pet food digestibility. Various commercial pet food formats are now available, but few have been tested thoroughly. The objective of this study was to determine the amino acid (AA) digestibilities and nitrogen-corrected true metabolizable energy (TMEn) values of frozen raw, freeze-dried raw, fresh (mildly cooked), and extruded dog foods using the precision-fed cecectomized and conventional rooster assays. The diets tested were Chicken and Barley Recipe [Hill's Science Diet, extruded diet (EXT)], Chicken and White Rice Recipe [Just Food for Dogs, fresh diet (FRSH)], Chicken Formula [Primal Pet Foods, frozen raw diet (FRZN)], Chicken and Sorghum Hybrid Freeze-dried Formula [Primal Pet Foods, hybrid freeze-dried raw diet (HFD)], and Chicken Dinner Patties [Stella & Chewy's, freeze-dried raw diet (FD)]. Two precision-fed rooster assays utilizing Single Comb White Leghorn roosters were conducted. Cecectomized roosters (n = 4/treatment) and conventional roosters (n = 4/treatment) were used to determine standardized AA digestibilities and TMEn, respectively. All roosters were crop intubated with 12 g of test diet and 12 g of corn, with excreta collected for 48 h. In general, FD had the highest, while EXT had the lowest AA digestibilities; however, all diets performed relatively well and few differences in AA digestibility were detected among the diets. Lysine digestibility was higher (P < 0.05) in FD and FRZN than EXT, with other diets being intermediate. Threonine digestibility was higher (P < 0.05) in FD than EXT, with other diets being intermediate. Digestibilities of the other indispensable AA were not different among diets. The reactive lysine:total lysine ratios were 0.94, 0.96, 0.93, 0.93, and 0.95 for EXT, FRSH, FRZN, HFD, and FD, respectively. TMEn was higher (P < 0.05) in FRZN than FD, FRSH, and EXT, higher (P < 0.05) in HFD than FRSH and EXT, and higher (P < 0.05) in FD than EXT. In conclusion, our results support the notion that AA digestibilities are affected by diet processing, with FD, HFD, FRZN, and FRSH diets having higher AA digestibility coefficients and greater TMEn values, than the EXT diet; however, other factors such as ingredient inclusion and macronutrient composition may also have affected these results. More research in dogs is necessary to test the effects of format on diet palatability, digestibility, stool quality, and other physiologically relevant outcomes.


Processing conditions, particularly temperature and duration of heating, impact pet food digestibility. This study tested the standardized amino acid (AA) digestibilities and nitrogen-corrected true metabolizable energy (TMEn) values of five commercial dog diets: extruded diet (EXT), fresh (mildly cooked) diet (FRSH), frozen raw diet (FRZN), hybrid freeze-dried raw diet (HFD), and freeze-dried raw diet (FD). The first study, to determine AA digestibility, used 20 roosters who had their ceca (the main site of microbial fermentation in chickens) surgically removed. The second study used 20 conventional roosters to determine the TMEn of the diets. In general, FD had the highest AA digestibilities, while EXT had the lowest AA digestibilities. True metabolizable energy concentration was higher in the FRZN diet than the FD, FRSH, and EXT diets, higher in the HFD diet than the FRSH and EXT diets, and higher in the FD diet than the EXT diet. Our results support the notion that differences in diet processing, as well as factors such as macronutrient composition, and ingredient source, characteristics, and inclusion may impact AA digestibility and TMEn of dog diets. More research should be conducted to determine exactly how, and to what extent, these different factors impact digestibility in dogs.


Subject(s)
Amino Acids , Chickens , Animals , Male , Dogs , Amino Acids/metabolism , Chickens/metabolism , Lysine/metabolism , Animal Feed/analysis , Digestion/physiology , Diet/veterinary , Animal Nutritional Physiological Phenomena
2.
J Anim Sci ; 1012023 Jan 03.
Article in English | MEDLINE | ID: mdl-37097066

ABSTRACT

The use of various hemp-derived products has been rapidly growing in the human nutrition industry and has sparked great interest in using these ingredients for companion animals as well. Thorough research is needed to determine the ingredient and safety standards required for AAFCO approval of hemp ingredients. In order to be effectively incorporated into pet food products, we must determine the nutrient content, quality, and utility of these ingredients in pet species. The objective of this study was to evaluate the nutrient composition of seeds from four different varieties of hemp, NWG 452, NWG 331, NWG 2730, X-59, and determine protein quality and true metabolizable energy using a cecectomized rooster model. The seeds were similar in macronutrient composition, with small variations in acid hydrolyzed fat, crude protein, total dietary fiber and gross energy content, as well as amino acid and long-chain fatty acid profiles. All essential amino acids were present in concentrations that exceeded the NRC (2006) recommended allowances for adult dogs and cats at maintenance with the exception of tryptophan. The long-chain fatty acid profile presented a favorable ratio of omega-6 to omega-3 fatty acids of close to 3.5:1. The results of the cecectomized rooster assay indicated no significant difference in the standardized amino acid digestibility of the indispensable amino acids among the seed varieties (P > 0.05). A significant difference in the true metabolizable energy corrected for nitrogen was observed among the seeds (P < 0.05), following the pattern of higher acid hydrolyzed fat and lower total dietary fiber content resulting in higher metabolizable energy. An adapted calculation of digestible indispensable amino acid score was made to determine protein quality of the hemp seeds using AAFCO nutrient profiles and NRC recommended allowances for adult dogs and cats at maintenance as reference points. The resulting scores determined tryptophan to be the first limiting amino acid and indicate that hemp seeds alone do not meet all the amino acid requirements for adult dogs and cats at maintenance, and would need a complimentary protein source for practical use in companion animal diets. The data from this study suggest that hemp seeds may provide a beneficial source of fat, protein, and dietary fiber, with consideration to differences in nutrient profile among seed varieties. However, further investigation in vivo is needed to determine the safety and efficacy of utilizing hemp in the diets of both canines and felines.


Hemp products have become popular in the human food and health industry over the past few years. Due to this, a growing interest in using hemp ingredients in animal products has developed as well. There is a need to investigate the nutritional properties and potential utility of hemp seeds in food products for companion animals in order for them to be consumed safely and effectively. Four different varieties of hemp seed were evaluated and found to have similar fat, fiber, and protein content as well as protein quality. The results indicate that hemp seeds may be an advantageous ingredient in the development of pet food products, but a more in depth evaluation using pet species is necessary to confirm this.


Subject(s)
Cannabis , Cat Diseases , Dog Diseases , Cats , Animals , Dogs , Male , Humans , Amino Acids/metabolism , Cannabis/chemistry , Cannabis/metabolism , Chickens/metabolism , Tryptophan/metabolism , Digestion , Diet/veterinary , Nutrients/metabolism , Proteins/metabolism , Dietary Fiber/metabolism , Fatty Acids/metabolism , Animal Feed/analysis , Seeds/chemistry
3.
Nurs Manage ; 54(2): 16-23, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36735469
5.
Vet Parasitol Reg Stud Reports ; 25: 100601, 2021 07.
Article in English | MEDLINE | ID: mdl-34474794

ABSTRACT

Toxoplasma gondii, the cause of toxoplasmosis is an obligate intracellular protozoan parasite of veterinary and public health importance. Ground feeding birds play an active role in the epidemiology of the disease and are the best indicators of soil contamination with the oocysts. Thirteen (14.1%; 95% CI = 7.7-23.0) of the 92 wild birds (6 of Coliformes; 4 of Columbiformes; 67 of Passeriformes and 15 of Piciformes) captured from Shere hills and 43 (9.3%; 95%CI = 4.9-12.4) of the 460 local chickens obtained across 3 senatorial regions of Plateau State, Nigeria were positive for anti-T. gondii antibodies using enzyme linked immunosorbent assay (ELISA). Varying prevalence (16.7-100%) of anti-T. gondii antibodies were recorded across 10 of 35 wild bird species; 2 (28.6) of 7 African thrush (Turdus pelios), 2 (33.3) of 6 speckled mouse bird (Colius striatus), 1 (20.0%) of 5 speckled fronted weaver (Sporopipes frontalis), 1 (33.3%) of 3 Northern Red bishop (Euplectes franciscanus), 1 (50.0%) of 2 village weaver (Ploceus cucullatus), 2 (28.6%) of 7 common bulbul (Pycnonotus barbatus), 1 (50.0%) of 2 black crowned tchagra (Tchagra senegalus), 1 (50.0%) of 2 black billed wood dove (Turtur abyssinicus), 1 (100.0%) of 1 mocking cliff chat (Thamnolaea cinamomeiventris), 1 (16.7) of 6 vieillot's barbet (Lybius vieilloti). The prevalence did not vary significantly based on the sex (p = 0.14), feeding guild (p = 0.53) and the taxonomic order (p = 0.62) of the wild birds. Regional based prevalence among local chickens ranged between 8.0 and 11.8% across the 3 senatorial zones. The source (p = 0.513; 95% CI = 4.9-16.8) and age (p = 0.797; 95% CI = 4.9-16.8) of local chickens were not associated with T. gondii seropositivity. Seropositivity was higher in the females (95% CI = 9.1-18.3) than in the males (p = 0.004; 95% CI = 3.0-9.4). This is the first report of the serological evidence of exposure to T. gondii infection in a wide variety of wild birds and local chickens in the area. It suggest that birds in this region are important asymptomatic intermediate hosts and play a role in the maintenance of the organism in the ecosystem.


Subject(s)
Poultry Diseases/epidemiology , Rodent Diseases , Toxoplasmosis, Animal , Animals , Chickens , Ecosystem , Female , Male , Nigeria/epidemiology , Rodent Diseases/epidemiology , Seroepidemiologic Studies , Toxoplasma , Toxoplasmosis, Animal/epidemiology , Toxoplasmosis, Animal/parasitology
6.
J Wildl Dis ; 56(1): 16-26, 2020 01.
Article in English | MEDLINE | ID: mdl-31329521

ABSTRACT

Chlamydia psittaci typically infects birds and can cause outbreaks of avian chlamydiosis, but it also has the potential to cause zoonotic disease (psittacosis) in humans. To better understand the epidemiology of C. psittaci in Victoria, Australia, we conducted opportunistic sampling of more than 400 wild and captive birds presented to the Australian Wildlife Health Centre at Zoos Victoria's Healesville Sanctuary for veterinary care between December 2014 and December 2015. Samples were screened for the presence of chlamydial DNA using quantitative PCR, and positive samples were subjected to multilocus sequence typing analysis. The results showed a significantly higher prevalence of infection in captive birds (8%; 9/113) compared to wild birds (0.7%; 2/299). Multilocus sequence typing analysis revealed that C. psittaci sequence type 24 was detected in both wild and captive birds in the local region, while C. psittaci sequence type 27 was detected for the first time in an Australian avian host. The generally low prevalence of C. psittaci detection points to a generally low zoonotic risk to veterinary and support staff, although this risk may be higher when handling captive birds, where the prevalence of C. psittaci infection was almost 10-fold higher. Even with low rates of C. psittaci detection, appropriate hygiene and biosecurity practices are recommended due to the serious human health implications of infection with this pathogen.


Subject(s)
Animals, Wild , Bird Diseases/microbiology , Birds/microbiology , Chlamydophila psittaci/isolation & purification , Psittacosis/veterinary , Animals , Bird Diseases/epidemiology , Chlamydophila psittaci/genetics , DNA, Bacterial/genetics , Phylogeny , Population Surveillance , Psittacosis/epidemiology , Psittacosis/microbiology , Victoria/epidemiology
7.
J Emerg Med ; 57(5): e161-e165, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31594743

ABSTRACT

Postgraduate training in emergency medicine (EM) varies in length among different programs. This fact creates a dilemma for applicants to the specialty of EM and prevents EM educators from reaching a consensus regarding the optimal length of training. Historically, EM training existed in the postgraduate year (PGY) 1-3, 2-4, and 1-4 formats, until the PGY 2-4 program became obsolete in 2011-2012. Currently, three-quarters of EM programs follow the PGY 1-3 format. In this article, we clarify for the applicants the main differences between the PGY 1-3 and PGY 1-4 formats. We also discuss the institutional, personal, and graduate considerations that explain why an institution or an individual would choose one format over the other.


Subject(s)
Emergency Medicine/education , Internship and Residency/methods , Time Factors , Curriculum/standards , Curriculum/trends , Education, Medical, Graduate/methods , Education, Medical, Graduate/standards , Emergency Medicine/methods , Humans , Internship and Residency/standards , Teaching/psychology , Teaching/standards
8.
J Emerg Med ; 57(6): e199-e204, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31481321

ABSTRACT

There are currently 5 combined residencies in emergency medicine (EM), namely EM/pediatrics, EM/internal medicine, EM/internal medicine/critical care, EM/family medicine and EM/anesthesiology. These combined programs vary from 5-6 years in length. Like categorical programs, the decision to enter a 5- or 6-year program should be an informed and comprehensive decision. We describe the history and current status of the combined EM programs, discuss the process of applying to a combined EM program, describe the life of combined EM residents, and explore common career opportunities available to combined EM program graduates.


Subject(s)
Emergency Medicine/education , Internship and Residency/methods , Humans , Internship and Residency/trends , United States
9.
Parasit Vectors ; 12(1): 99, 2019 Mar 13.
Article in English | MEDLINE | ID: mdl-30867019

ABSTRACT

BACKGROUND: Sarcoptic mange, caused by the Sarcoptes scabiei mite, is an infectious disease of wildlife, domestic animals and humans with international importance. Whilst a variety of treatment and control methods have been investigated in wildlife, the literature is fragmented and lacking consensus. The primary objectives of this review were to synthesise the diverse literature published on the treatment of sarcoptic mange in wildlife from around the world, and to identify the qualities of successful treatment strategies in both captive and free-roaming wildlife. METHODS: A systematic search of the electronic databases CAB Direct, PubMed, Scopus, Web of Science, EMBASE and Discovery was undertaken. Data pertaining to study design, country, year, species, study size, mange severity, treatment protocol and outcomes were extracted from eligible studies and placed in a table. Following data extraction, a decision tree was used to identify studies suitable for further analysis based on the effectiveness of their treatment protocol, whether they were conducted on captive or non-captive wildlife, and the quality of their post-treatment monitoring period. RESULTS: Twenty-eight studies met our initial inclusion criteria for data collection. Of these studies, 15 were selected for further analysis following application of the decision tree. This comprised of 9 studies on captive wildlife, 5 studies on free-living wildlife and 1 study involving both captive and free-living wildlife. Ivermectin delivered multiple times via subcutaneous injection at a dose between 200-400 µg/kg was found to be the most common and successfully used treatment, although long-term data on post-release survival and re-infection rates was elusive. CONCLUSIONS: To our knowledge, this review is the first to demonstrate that multiple therapeutic protocols exist for the treatment of sarcoptic mange in wildlife. However, several contemporary treatment options are yet to be formally reported in wildlife, such as the use of isoxazoline chemicals as a one-off treatment. There is also a strong indication for more randomised controlled trials, as well as improved methods of post-treatment monitoring. Advancing this field of knowledge is expected to aid veterinarians, wildlife workers and policy makers with the design and implementation of effective treatment and management strategies for the conservation of wildlife affected by sarcoptic mange.


Subject(s)
Insecticides/administration & dosage , Ivermectin/administration & dosage , Sarcoptes scabiei/drug effects , Scabies/drug therapy , Animals , Animals, Domestic , Animals, Wild , Conservation of Natural Resources , Humans , Injections, Subcutaneous , Scabies/parasitology , Treatment Outcome
10.
Risk Anal ; 39(5): 1169-1191, 2019 05.
Article in English | MEDLINE | ID: mdl-30428498

ABSTRACT

Aquatic non-native invasive species are commonly traded in the worldwide water garden and aquarium markets, and some of these species pose major threats to the economy, the environment, and human health. Understanding the potential suitable habitat for these species at a global scale and at regional scales can inform risk assessments and predict future potential establishment. Typically, global habitat suitability models are fit for freshwater species with only climate variables, which provides little information about suitable terrestrial conditions for aquatic species. Remotely sensed data including topography and land cover data have the potential to improve our understanding of suitable habitat for aquatic species. In this study, we fit species distribution models using five different model algorithms for three non-native aquatic invasive species with bioclimatic, topographic, and remotely sensed covariates to evaluate potential suitable habitat beyond simple climate matches. The species examined included a frog (Xenopus laevis), toad (Bombina orientalis), and snail (Pomacea spp.). Using a unique modeling approach for each species including background point selection based on known established populations resulted in robust ensemble habitat suitability models. All models for all species had test area under the receiver operating characteristic curve values greater than 0.70 and percent correctly classified values greater than 0.65. Importantly, we employed multivariate environmental similarity surface maps to evaluate potential extrapolation beyond observed conditions when applying models globally. These global models provide necessary forecasts of where these aquatic invasive species have the potential for establishment outside their native range, a key component in risk analyses.


Subject(s)
Conservation of Natural Resources/methods , Ecosystem , Gardening/methods , Gardens , Introduced Species , Risk Assessment/methods , Algorithms , Animals , Anura , Climate , Climate Change , Fresh Water , Models, Theoretical , Multivariate Analysis , Snails , Water , Xenopus
11.
Aquat Invasions ; 13(3): 323-338, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-31447950

ABSTRACT

Understanding the spatial and temporal dynamics underlying the introduction and spread of nonindigenous aquatic species (NAS) can provide important insights into the historical drivers of biological invasions and aid in forecasting future patterns of nonindigenous species arrival and spread. Increasingly, public databases of species observation records are being used to quantify changes in NAS distributions across space and time, and are becoming an important resource for researchers, managers, and policy-makers. Here we use publicly available data to describe trends in NAS introduction and spread across the conterminous United States over more than two centuries of observation records. Available data on first records of NAS reveal significant shifts in dominance of particular introduction patterns over time, both in terms of recipient regions and likely sources. These spatiotemporal trends at the continental scale may be subject to biases associated with regional variation in sampling effort, reporting, and data curation. We therefore also examined two additional metrics, the number of individual records and the spatial coverage of those records, which are likely to be more closely associated with sampling effort. Our results suggest that broad-scale patterns may mask considerable variation across regions, time periods, and even entities contributing to NAS sampling. In some cases, observed temporal shifts in species discovery may be influenced by dramatic fluctuations in the number and spatial extent of individual observations, reflecting the possibility that shifts in sampling effort may obscure underlying rates of NAS introduction.

12.
J Med Microbiol ; 65(5): 420-428, 2016 May.
Article in English | MEDLINE | ID: mdl-26932792

ABSTRACT

Chlamydia pecorum infection is a threat to the health of free-ranging koalas (Phascolarctos cinereus) in Australia. Utilizing an extensive sample archive we determined the prevalence of C. pecorum in koalas within six regions of Victoria, Australia. The ompA genotypes of the detected C. pecorum were characterized to better understand the epidemiology of this pathogen in Victorian koalas. Despite many studies in northern Australia (i.e. Queensland and New South Wales), prior Chlamydia studies in Victorian koalas are limited. We detected C. pecorum in 125/820 (15 %) urogenital swabs, but in only one ocular swab. Nucleotide sequencing of the molecular marker C. pecorum ompA revealed that the majority (90/114) of C. pecorum samples typed were genotype B. This genotype has not been reported in northern koalas. In general, Chlamydia infection in Victorian koalas is associated with milder clinical signs compared with infection in koalas in northern populations. Although disease pathogenesis is likely to be multifactorial, the high prevalence of genotype B in Victoria may suggest it is less pathogenic. All but three koalas had C. pecorum genotypes unique to southern koala populations (i.e. Victoria and South Australia). These included a novel C. pecorum ompA genotype and two genotypes associated with livestock. Regression analysis determined that significant factors for the presence of C. pecorum infection were sex and geographical location. The presence of 'wet bottom' in males and the presence of reproductive tract pathology in females were significantly associated with C. pecorum infection, suggesting variation in clinical disease manifestations between sexes.


Subject(s)
Chlamydia Infections/veterinary , Chlamydia/genetics , Marsupialia/microbiology , Animals , Bacterial Outer Membrane Proteins/genetics , Bacterial Outer Membrane Proteins/metabolism , Chlamydia/classification , Chlamydia Infections/epidemiology , Chlamydia Infections/microbiology , Female , Gene Expression Regulation, Bacterial , Genotype , Male , Victoria/epidemiology
13.
Schizophr Res ; 168(3): 661-70, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26088421

ABSTRACT

Late adolescence in males is a period of increased susceptibility for the onset of schizophrenia, coinciding with increased circulating testosterone. The cognitive deficits prevalent in schizophrenia may be related to unhealthy cortical interneurons, which are trophically dependent on brain derived neurotrophic factor. We investigated, under conditions of depleted (monkey and rat) and replaced (rat) testosterone over adolescence, changes in gene expression of cortical BDNF and TrkB transcripts and interneuron markers and the relationships between these mRNAs and circulating testosterone. Testosterone removal by gonadectomy reduced gene expression of some BDNF transcripts in monkey and rat frontal cortices and the BDNF mRNA reduction was prevented by testosterone replacement. In rat, testosterone replacement increased the potential for classical TrkB signalling by increasing the full length to truncated TrkB mRNA ratio, whereas in the monkey cortex, circulating testosterone was negatively correlated with the TrkB full length/truncated mRNA ratio. We did not identify changes in interneuron gene expression in monkey frontal cortex in response to gonadectomy, and in rat, we showed that only somatostatin mRNA was decreased by gonadectomy but not restored by testosterone replacement. We identified complex and possibly species-specific, relationships between BDNF/TrkB gene expression and interneuron marker gene expression that appear to be dependent on the presence of testosterone at adolescence in rat and monkey frontal cortices. Taken together, our findings suggest there are dynamic relationships between BDNF/TrkB and interneuron markers that are dependent on the presence of testosterone but that this may not be a straightforward increase in testosterone leading to changes in BDNF/TrkB that contributes to interneuron health.


Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Frontal Lobe/growth & development , Frontal Lobe/metabolism , Interneurons/metabolism , Receptor, trkB/metabolism , Testosterone/metabolism , Animals , Hormones/administration & dosage , Macaca mulatta , Male , Nerve Growth Factors/metabolism , Orchiectomy , RNA, Messenger/metabolism , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Somatostatin/metabolism , Species Specificity , Testosterone/administration & dosage
14.
J Vis Exp ; (84): e50872, 2014 Feb 19.
Article in English | MEDLINE | ID: mdl-24637937

ABSTRACT

Current knowledge of sensory processing in the mammalian auditory system is mainly derived from electrophysiological studies in a variety of animal models, including monkeys, ferrets, bats, rodents, and cats. In order to draw suitable parallels between human and animal models of auditory function, it is important to establish a bridge between human functional imaging studies and animal electrophysiological studies. Functional magnetic resonance imaging (fMRI) is an established, minimally invasive method of measuring broad patterns of hemodynamic activity across different regions of the cerebral cortex. This technique is widely used to probe sensory function in the human brain, is a useful tool in linking studies of auditory processing in both humans and animals and has been successfully used to investigate auditory function in monkeys and rodents. The following protocol describes an experimental procedure for investigating auditory function in anesthetized adult cats by measuring stimulus-evoked hemodynamic changes in auditory cortex using fMRI. This method facilitates comparison of the hemodynamic responses across different models of auditory function thus leading to a better understanding of species-independent features of the mammalian auditory cortex.


Subject(s)
Auditory Cortex/anatomy & histology , Auditory Cortex/physiology , Cats/anatomy & histology , Cats/physiology , Magnetic Resonance Imaging/methods , Animals , Auditory Cortex/blood supply , Hemodynamics , Magnetic Resonance Imaging/instrumentation , Models, Animal
15.
Am J Psychiatry ; 171(3): 323-31, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24480874

ABSTRACT

OBJECTIVE: This study examined the long-term effects of fluoxetine administered to juvenile rhesus monkeys who, as young adults, were imaged with positron emission tomography for two serotonergic markers: serotonin transporter (SERT) and serotonin 1A (5-HT1A) receptor. An equal number of monkeys separated from their mothers at birth-an animal model of human childhood stress-were also studied. METHOD: At birth, 32 male rhesus monkeys were randomly assigned to either maternal separation or normal rearing conditions. At age 2, half (N=8) of each group was randomly assigned to fluoxetine (3 mg/kg) or placebo for 1 year. To eliminate the confounding effects of residual drug in the brain, monkeys were scanned at least 1.5 years after drug discontinuation. Social interactions were assessed both during and after drug administration. RESULTS: Fluoxetine persistently upregulated SERT, but not 5-HT1A receptors, in both the neocortex and the hippocampus. Whole-brain voxel-wise analysis revealed that fluoxetine had a significant effect in the lateral temporal and cingulate cortices. In contrast, neither maternal separation by itself nor the rearing-by-drug interaction was significant for either marker. Fluoxetine had no significant effect on the behavioral measures. CONCLUSIONS: Fluoxetine administered to juvenile monkeys upregulates SERT into young adulthood. Implications regarding the efficacy or potential adverse effects of SSRIs in patients cannot be directly drawn from this study. Its purpose was to investigate effects of SSRIs on brain development in nonhuman primates using an experimental approach that randomly assigned long-term SSRI treatment or placebo.


Subject(s)
Fluoxetine/pharmacology , Hippocampus/metabolism , Interpersonal Relations , Maternal Deprivation , Neocortex/metabolism , Serotonin Plasma Membrane Transport Proteins/metabolism , Age Factors , Animals , Functional Neuroimaging , Hippocampus/diagnostic imaging , Macaca mulatta , Male , Neocortex/diagnostic imaging , Neocortex/drug effects , Radionuclide Imaging , Receptor, Serotonin, 5-HT1A/metabolism , Selective Serotonin Reuptake Inhibitors/pharmacology , Up-Regulation
16.
J Neurosci Methods ; 224: 96-106, 2014 Mar 15.
Article in English | MEDLINE | ID: mdl-24389047

ABSTRACT

When conducting auditory investigations using functional magnetic resonance imaging (fMRI), there are inherent potential confounds that need to be considered. Traditional continuous fMRI acquisition methods produce sounds >90 dB which compete with stimuli or produce neural activation masking evoked activity. Sparse scanning methods insert a period of reduced MRI-related noise, between image acquisitions, in which a stimulus can be presented without competition. In this study, we compared sparse and continuous scanning methods to identify the optimal approach to investigate acoustically evoked cortical, thalamic and midbrain activity in the cat. Using a 7 T magnet, we presented broadband noise, 10 kHz tones, or 0.5 kHz tones in a block design, interleaved with blocks in which no stimulus was presented. Continuous scanning resulted in larger clusters of activation and more peak voxels within the auditory cortex. However, no significant activation was observed within the thalamus. Also, there was no significant difference found, between continuous or sparse scanning, in activations of midbrain structures. Higher magnitude activations were identified in auditory cortex compared to the midbrain using both continuous and sparse scanning. These results indicate that continuous scanning is the preferred method for investigations of auditory cortex in the cat using fMRI. Also, choice of method for future investigations of midbrain activity should be driven by other experimental factors, such as stimulus intensity and task performance during scanning.


Subject(s)
Brain Mapping , Magnetic Resonance Imaging , Visual Cortex/blood supply , Acoustic Stimulation , Animals , Cats , Female , Image Processing, Computer-Assisted , Oxygen/blood , Psychoacoustics , Visual Cortex/physiology
17.
Neuroimage ; 64: 458-65, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23000258

ABSTRACT

Much of what is known about the cortical organization for audition in humans draws from studies of auditory cortex in the cat. However, these data build largely on electrophysiological recordings that are both highly invasive and provide less evidence concerning macroscopic patterns of brain activation. Optical imaging, using intrinsic signals or dyes, allows visualization of surface-based activity but is also quite invasive. Functional magnetic resonance imaging (fMRI) overcomes these limitations by providing a large-scale perspective of distributed activity across the brain in a non-invasive manner. The present study used fMRI to characterize stimulus-evoked activity in auditory cortex of an anesthetized (ketamine/isoflurane) cat, focusing specifically on the blood-oxygen-level-dependent (BOLD) signal time course. Functional images were acquired for adult cats in a 7 T MRI scanner. To determine the BOLD signal time course, we presented 1s broadband noise bursts between widely spaced scan acquisitions at randomized delays (1-12 s in 1s increments) prior to each scan. Baseline trials in which no stimulus was presented were also acquired. Our results indicate that the BOLD response peaks at about 3.5s in primary auditory cortex (AI) and at about 4.5 s in non-primary areas (AII, PAF) of cat auditory cortex. The observed peak latency is within the range reported for humans and non-human primates (3-4 s). The time course of hemodynamic activity in cat auditory cortex also occurs on a comparatively shorter scale than in cat visual cortex. The results of this study will provide a foundation for future auditory fMRI studies in the cat to incorporate these hemodynamic response properties into appropriate analyses of cat auditory cortex.


Subject(s)
Auditory Cortex/physiology , Brain Mapping/methods , Evoked Potentials, Auditory/physiology , Magnetic Resonance Imaging/methods , Oxygen Consumption/physiology , Oxygen/blood , Pitch Perception/physiology , Animals , Cats
18.
Ophthalmic Epidemiol ; 19(3): 127-36, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22568425

ABSTRACT

PURPOSE: Retinal vessels may provide a readily accessible surrogate approach to study vascular disease in brain small vessels. Previous epidemiologic studies of retinal microvascular abnormalities and cognition have not included large numbers of Latinos who have a high prevalence of diabetes and hypertension. METHODS: We used data from 809 elderly Latino participants in the Los Angeles Latino Eye Study (LALES) to assess whether retinal vessel caliber and microvascular abnormalities are cross-sectionally associated with lower cognitive function. Cognitive screening was conducted with the Cognitive Abilities Screening Instrument-Short form (CASI-S) and in-depth testing with the Spanish English Neuropsychological Assessment Scales (SENAS). Retinal photographs were used to identify retinopathy signs and measure retinal vessel caliber. RESULTS: A total of 65.8% had high blood pressure, 34.5% had diabetes; self-reported diagnoses of heart attack, heart failure, angina and stroke were rare. Retinal calibers and any retinopathy were not associated with the CASI-S, total SENAS or any SENAS cognitive factors assessed as continuous variables. The odds of a low CASI-S score were two times higher in subjects with generalized arteriolar narrowing (OR = 2.04, 95% CI = 1.14, 3.66), and one and half times as high in those with both generalized arteriolar narrowing and retinopathy signs (OR = 1.49, 95% CI = 0.47, 4.75) though this result was based on only four cases with both risk factors and confidence limits were wide and included the null. CONCLUSION: Retinal microvasculature imaging may provide insights into small blood vessel influences on cognition in Latino populations. Additional studies in diverse populations and prospective settings are needed.


Subject(s)
Cognition Disorders/ethnology , Hispanic or Latino/ethnology , Retinal Diseases/ethnology , Retinal Vessels/pathology , Aged , Cardiovascular Diseases/ethnology , Cognition Disorders/diagnosis , Diabetes Mellitus/ethnology , Educational Status , Female , Humans , Hypertension/ethnology , Los Angeles/epidemiology , Male , Neuropsychological Tests , Photography , Retinal Diseases/diagnosis , Risk Factors
19.
J Wildl Dis ; 48(1): 226-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22247398

ABSTRACT

A second novel gammaherpesvirus was detected in a free-ranging koala (Phascolarctos cinereus) shown previously to be infected with phascolarctid herpesvirus 1. Analysis of the DNA polymerase gene showed that the virus was genetically distinct from all known gammaherpesviruses. This is the first reported dual gammaherpesvirus infection in an Australian marsupial.


Subject(s)
DNA, Viral/analysis , Gammaherpesvirinae/isolation & purification , Phascolarctidae/virology , Animals , Animals, Wild , Polymerase Chain Reaction/veterinary
20.
Am J Public Health ; 102(4): 689-97, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21852626

ABSTRACT

OBJECTIVES: We considered interactions between physical activity and body mass index (BMI) and neighborhood factors. METHODS: We used recursive partitioning to identify predictors of low recreational physical activity (< 2.5 hours/week) and overweight and obesity (BMI ≥ 25.0 kg/m(2)) among 118,315 women in the California Teachers Study. Neighborhood characteristics were based on 2000 US Census data and Reference US business listings. RESULTS: Low physical activity and being overweight or obese were associated with individual sociodemographic characteristics, including race/ethnicity and age. Among White women aged 36 to 75 years, living in neighborhoods with more household crowding was associated with a higher probability of low physical activity (54% vs 45% to 51%). In less crowded neighborhoods where more people worked outside the home, the existence of fewer neighborhood amenities was associated with a higher probability of low physical activity (51% vs 46%). Among non-African American middle-aged women, living in neighborhoods with a lower socioeconomic status was associated with a higher probability of being overweight or obese (46% to 59% vs 38% in high-socioeconomic status neighborhoods). CONCLUSIONS: Associations between physical activity, overweight and obesity, and the built environment varied by sociodemographic characteristics in this educated population.


Subject(s)
Body Mass Index , Exercise/physiology , Faculty , Residence Characteristics , Adult , Aged , Body Size , California/epidemiology , Cohort Studies , Environment Design , Female , Humans , Middle Aged , Obesity/epidemiology , Obesity/ethnology , Overweight/epidemiology , Overweight/ethnology , Prospective Studies , Social Class , Surveys and Questionnaires
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