@article{salzman_takimoto_foster_mowat_2024, title={Differential gene expression between central and peripheral retinal regions in dogs and comparison with humans}, volume={245}, ISSN={["1096-0007"]}, DOI={10.1016/j.exer.2024.109980}, abstractNote={The dog retina contains a central macula-like region, and there are reports of central retinal disorders in dogs with shared genetic etiologies with humans. Defining central/peripheral gene expression profiles may provide insight into the suitability of dogs as models for human disorders. We determined central/peripheral posterior eye gene expression profiles in dogs and interrogated inherited retinal and macular disease-associated genes for differential expression between central and peripheral regions. Bulk tissue RNA sequencing was performed on 8 mm samples of the dog central and superior peripheral regions, sampling retina and retinal pigmented epithelium/choroid separately. Reads were mapped to CanFam3.1, read counts were analyzed to determine significantly differentially expressed genes (DEGs). A similar analytic pipeline was used with a published bulk-tissue RNA sequencing human dataset. Pathways and processes involved in significantly DEGs were identified (Database for Annotation, Visualization and Integrated Discovery). Dogs and humans shared the extent and direction of central retinal differential gene expression, with multiple shared biological pathways implicated in differential expression. Many genes implicated in heritable retinal disorders in dogs and humans were differentially expressed between central and periphery. Approximately half of genes associated with human age-related macular degeneration were differentially expressed in human and dog tissues. We have identified similarities and differences in central/peripheral gene expression profiles between dogs and humans which can be applied to further define the relevance of dogs as models for human retinal disorders.}, journal={EXPERIMENTAL EYE RESEARCH}, author={Salzman, Michele M. and Takimoto, Tetsuya and Foster, Melanie L. and Mowat, Freya M.}, year={2024}, month={Aug} }
 @article{wise_foster_kremers_mowat_2021, title={A modified silent substitution electroretinography protocol to separate photoreceptor subclass function in lightly sedated dogs}, volume={24}, ISSN={["1463-5224"]}, DOI={10.1111/vop.12847}, abstractNote={Abstract}, number={1}, journal={VETERINARY OPHTHALMOLOGY}, author={Wise, E. N. and Foster, M. L. and Kremers, J. and Mowat, F. M.}, year={2021}, month={Jan}, pages={103–107} }
 @article{heyward_reynolds_foster_archibald_stoskopf_mowat_2021, title={Retinal cone photoreceptor distribution in the American black bear (Ursus americanus)}, volume={304}, ISSN={["1932-8494"]}, DOI={10.1002/ar.24472}, abstractNote={Abstract}, number={3}, journal={ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY}, author={Heyward, Jennifer L. and Reynolds, Benjamin D. and Foster, Melanie L. and Archibald, Kate E. and Stoskopf, Michael K. and Mowat, Freya M.}, year={2021}, month={Mar}, pages={662–672} }
 @article{dorman_foster_lazarowski_2021, title={Training with Multiple Structurally Related Odorants Fails to Improve Generalization of Ammonium Nitrate Detection in Domesticated Dogs (Canis familiaris)}, volume={11}, ISSN={["2076-2615"]}, DOI={10.3390/ani11010213}, abstractNote={A critical aspect of canine scent detection involves the animal’s ability to respond to odors based on prior odor training. In the current study, dogs (n = 12) were initially trained on an olfactory simple discrimination task using vanillin as the target odorant. Based on their performance on this task, dogs were assigned to experimental groups. Dogs in group 1 and 2 (n = 5 dogs/group; 1 dog/group were removed due to low motivation or high error rates) were trained with either two or six forms of ammonium nitrate (AN), respectively. Dogs were then assessed with a mock explosive with AN and powdered aluminum. Dogs in both groups failed to respond to the novel AN-aluminum odor. Mean success rates were 56 ± 5 and 54 ± 4% for groups 1 and 2, respectively. Overall, and individual dog performance was not statistically higher than chance indicating that dogs did not generalize from AN to a similar AN-based odorant at reliable levels desired for explosive detection dogs. These results suggest the use of authentic explosive materials, without the added complication of including category-learning methods, likely remains a cost-effective and efficient way to train explosive scent detection dogs.}, number={1}, journal={ANIMALS}, author={Dorman, David C. and Foster, Melanie L. and Lazarowski, Lucia}, year={2021}, month={Jan} }
 @article{mowat_avelino_bowyer_parslow_westermeyer_foster_fogle_bizikova_2020, title={Detection of circulating anti-retinal antibodies in dogs with sudden acquired retinal degeneration syndrome using indirect immunofluorescence: A case control study}, volume={193}, ISSN={["1096-0007"]}, DOI={10.1016/j.exer.2020.107989}, abstractNote={Sudden acquired retinal degeneration syndrome (SARDS) in dogs is proposed to have an immune-mediated etiology. However, there is conflicting evidence regarding the presence of antiretinal antibodies, as assessed by western blotting, in the serum of SARDS patients. Because of the possibility that antibodies recognize only conformational epitopes, we hypothesized that a more sensitive method to investigate circulating retinal autoantibodies in SARDS is immunofluorescence. Sera from 14 dogs with early SARDS, and 14 age- and breed-matched healthy control dogs were screened for circulating antiretinal IgG, IgM, IgE and IgA using indirect immunofluorescence on lightly fixed frozen sections of normal canine retina. Controls without canine serum were also performed. A nuclear counterstain was used to identify cellular retinal layers. Images were obtained using a fluorescence microscope, and 2-3 separate masked observers graded retinal layers for fluorescence staining intensity using a 0–3 scale. Total circulating IgG and IgM was assessed by radial immunodiffusion. Statistical analysis was performed using 2-way ANOVA, paired 2-tailed student's t-test and correlation analysis. Intensity of IgG staining of photoreceptor outer segments was significantly higher using serum from dogs with SARDS compared with healthy controls in 2/3 observers (P < 0.05). Intensity of IgM staining throughout the retina was higher in SARDS dogs compared to matched healthy controls (P < 0.0001), although no specific retinal layer was statistically significant. There were no differences in staining intensity for IgE or IgA. Dogs with SARDS had a comparably lower circulating IgG and higher IgM than healthy controls (P = 0.01 and 0.001 respectively) and IgG and IgM were negatively correlated (r = −0.69, P = 0.007). Despite having decreased serum IgG compared with healthy controls, circulating IgG in dogs with SARDS binds photoreceptor outer segments to a greater extent. Dogs with SARDS have a relatively higher circulating IgM than matched healthy controls. The pathogenic nature of these antibodies is unknown.}, journal={EXPERIMENTAL EYE RESEARCH}, author={Mowat, Freya M. and Avelino, Janelle and Bowyer, Ashley and Parslow, Vanessa and Westermeyer, Hans D. and Foster, Melanie L. and Fogle, Jonathan E. and Bizikova, Petra}, year={2020}, month={Apr} }
 @article{oh_foster_lunn_mowat_2019, title={Circulating neurohormone imbalances in canine sudden acquired retinal degeneration syndrome and canine pituitary-dependent hypercortisolism}, volume={33}, ISSN={["1939-1676"]}, DOI={10.1111/jvim.15646}, abstractNote={Abstract}, number={6}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Oh, Annie and Foster, Melanie L. and Lunn, Katharine F. and Mowat, Freya M.}, year={2019}, month={Nov}, pages={2587–2594} }
 @article{oh_foster_williams_zheng_ru_lunn_mowat_2019, title={Diagnostic utility of clinical and laboratory test parameters for differentiating between sudden acquired retinal degeneration syndrome and pituitary‐dependent hyperadrenocorticism in dogs}, volume={22}, ISSN={1463-5216 1463-5224}, url={http://dx.doi.org/10.1111/vop.12661}, DOI={10.1111/vop.12661}, abstractNote={Abstract}, number={6}, journal={Veterinary Ophthalmology}, publisher={Wiley}, author={Oh, Annie and Foster, Melanie L. and Williams, Jonathan G. and Zheng, Chaowen and Ru, Hongyu and Lunn, Katharine F. and Mowat, Freya M.}, year={2019}, month={Mar}, pages={842–858} }
 @article{mowat_wise_oh_foster_kremers_2019, title={In vivo electroretinographic differentiation of rod, short-wavelength and long/medium-wavelength cone responses in dogs using silent substitution stimuli}, volume={185}, ISSN={["1096-0007"]}, DOI={10.1016/j.exer.2019.05.013}, abstractNote={The canine species has dichromatic color vision comprising short-wavelength (S-) and long/medium (L/M-) wavelength-sensitive cones with peak spectral sensitivity of 429–435 nm and 555 nm respectively. Although differentiation of rod- and cone-mediated responses by electroretinogram (ERG) in dogs is commonly performed, and standards have been developed based on standards for human observers, methods to differentiate S- and L/M-cone responses in dogs have not been described. We developed flicker protocols derived from previously published rod and cone spectral sensitivities. We used a double silent substitution paradigm to isolate responses from each of the 3 photoreceptor subclasses. ERG responses were measured to sine-wave modulation of photoreceptor excitation at different temporal frequencies (between 4 and 56 Hz) and mean luminance (between 3.25 and 130 cd/m2) on 6 different normal dogs (3 adult female, and 3 adult male beagles) and one female beagle dog with suspected hereditary congenital stationary night blindness (CSNB). Peak rod driven response amplitudes were achieved with low frequency (4 Hz, maximal range 4–12 Hz) and low mean luminance (3.25 cd/m2). In contrast, peak L/M-cone driven response amplitudes were achieved with high frequency (32 Hz, maximal range 28–44 Hz) and high mean luminance (32.5–130 cd/m2). Maximal S-cone driven responses were obtained with low frequency stimuli (4 Hz, maximal range 4–12 Hz) and 32.5–130 cd/m2 mean luminance. The dog with CSNB had reduced rod- and S-cone-driven responses, but normal/supernormal L/M cone-driven responses. We have developed methods to differentiate rod, S- and L/M-cone function in dogs using silent substitution methods. The influence of temporal frequency and mean luminance on the ERGs originating in each photoreceptor type can now be studied independently. Dogs and humans have similar L/M cone responses, whereas mice have significantly different L/M responses. This work will facilitate a greater understanding of canine retinal electrophysiology and will complement the study of canine models of human hereditary photoreceptor disorders.}, journal={EXPERIMENTAL EYE RESEARCH}, author={Mowat, Freya M. and Wise, Elisabeth and Oh, Annie and Foster, Melanie L. and Kremers, Jan}, year={2019}, month={Aug} }
 @article{young_oh_williams_foster_miller_lunn_mowat_2018, title={Clinical therapeutic efficacy of mycophenolate mofetil in the treatment of SARDS in dogs-a prospective open-label pilot study}, volume={21}, ISSN={["1463-5224"]}, DOI={10.1111/vop.12545}, abstractNote={Abstract}, number={6}, journal={VETERINARY OPHTHALMOLOGY}, author={Young, Whitney M. and Oh, Annie and Williams, Jonathan G. and Foster, Melanie L. and Miller, William W. and Lunn, Katharine F. and Mowat, Freya M.}, year={2018}, month={Nov}, pages={565–576} }
 @article{foster_bartnikas_maresca-fichter_mercadante_dash_miller_dorman_2018, title={Neonatal C57BL/6J and parkin mice respond differently following developmental manganese exposure: Result of a high dose pilot study}, volume={64}, ISSN={["1872-9711"]}, DOI={10.1016/j.neuro.2017.10.002}, abstractNote={It has been suggested that childhood exposure to neurotoxicants may increase the risk of Parkinson's disease (PD) or other neurodegenerative disease in adults. Some recessive forms of PD have been linked to loss-of-function mutations in the Park2 gene that encodes for parkin. The purpose of this pilot study was to evaluate whether responses to neonatal manganese (Mn) exposure differ in mice with a Park2 gene defect (parkin mice) when compared with a wildtype strain (C57BL/6J). Neonatal parkin and C57BL/6J littermates were randomly assigned to 0, 11, or 25mg Mn/kg-day dose groups with oral exposures occurring from postnatal day (PND) 1 through PND 28. Motor activity was measured on PND 19-22 and 29-32. Tissue Mn concentrations were measured in liver, femur, olfactory bulb, frontal cortex, and striatum on PND 29. Hepatic and frontal cortex gene expression of Slc11a2, Slc40a1, Slc30a10, Hamp (liver only), and Park2 were also measured on PND 29. Some strain differences were seen. As expected, decreased hepatic and frontal cortex Park2 expression was seen in the parkin mice when compared with C57BL/6J mice. Untreated parkin mice also had higher liver and femur Mn concentrations when compared with the C57BL/6J mice. Exposure to≥11mg Mn/kg-day was associated with increased brain Mn concentrations in all mice, no strain difference was observed. Manganese exposure in C57Bl6, but not parkin mice, was associated with a negative correlation between striatal Mn concentration and motor activity. Manganese exposure was not associated with changes in frontal cortex gene expression. Decreased hepatic Slc30a10, Slc40a1, and Hamp expression were seen in PND 29 C57BL/6J mice given 25mg Mn/kg-day. In contrast, Mn exposure was only associated with decreased Hamp expression in the parkin mice. Our results suggest that the Parkin gene defect did not increase the susceptibility of neonatal mice to adverse health effects associated with high-dose Mn exposure.}, journal={NEUROTOXICOLOGY}, author={Foster, Melanie L. and Bartnikas, Thomas B. and Maresca-Fichter, Hailey C. and Mercadante, Courtney and Dash, Miriam and Miller, Chelsea and Dorman, David C.}, year={2018}, month={Jan}, pages={291–299} }
 @article{foster_rao_francher_traver_dorman_2018, title={Olfactory toxicity in rats following manganese chloride nasal instillation: A pilot study}, volume={64}, ISSN={["1872-9711"]}, DOI={10.1016/j.neuro.2017.09.004}, abstractNote={Following inhalation, manganese travels along the olfactory nerve from the olfactory epithelium (OE) to the olfactory bulb (OB). Occupational exposure to inhaled manganese is associated with changes in olfactory function. This pilot study evaluated two related hypotheses: (a) intranasal manganese administration increases OE and OB manganese concentrations; and (b) intranasal manganese exposure impairs performance of previously trained rats on a go-no-go olfactory discrimination (OD) task. Male Fischer 344 rats were trained to either lever press (“go”) in response to a positive conditioned stimulus (CS+: vanillin) or to do nothing (“no go”) when a negative conditioned stimulus (CS−: amyl acetate) was present. Following odor training, rats were randomly assigned to either a manganese (200 mM MnCl2) or 0.9% saline treatment group (n = 4–5 rats/group). Administration of either saline or manganese was performed on isoflurane-anesthetized rats as 40 μL bilateral intranasal instillations. Rats were retested 48 h later using the vanillin/amyl acetate OD task, then euthanized, followed by collection of the OE and OB. Manganese concentrations in tissue samples were analyzed by ICP-MS. An additional cohort of rats (n = 3–4/group) was instilled similarly with saline or manganese and nasal and OB pathology assessed 48 h later. Manganese-exposed rats had increased manganese levels in both the OE and OB and decreased performance in the OD task when compared with control animals. Histopathological evaluation of the caudal nasal cavity showed moderate, acute to subacute suppurative inflammation of the olfactory epithelium and submucosa of the ethmoid turbinates and mild suppurative exudate in the nasal sinuses in animals given manganese. No histologic changes were evident in the OB. The nasal instillation and OD procedures developed in this study are useful methods to assess manganese – induced olfactory deficits.}, journal={NEUROTOXICOLOGY}, author={Foster, Melanie L. and Rao, Deepa B. and Francher, Taylor and Traver, Samantha and Dorman, David C.}, year={2018}, month={Jan}, pages={284–290} }
 @article{oh_loew_foster_davidson_english_gervais_herring_mowat_2018, title={Phenotypic characterization of complete CSNB in the inbred research beagle: how common is CSNB in research and companion dogs?}, volume={137}, ISSN={["1573-2622"]}, DOI={10.1007/s10633-018-9653-y}, abstractNote={{"Label"=>"PURPOSE"} Although congenital stationary night blindness (CSNB) has been described in a Japanese beagle dog research colony, certain clinical correlates with human CSNB have not yet been described, nor has an estimate of frequency of the condition been made in inbred and outbred beagle populations. {"Label"=>"METHODS"} A beagle with CSNB obtained from a commercial research dog supplier in the USA and matched control dogs (n = 3) underwent examination, refraction, ocular imaging, assessment of visual navigation ability and detailed electroretinography (ERG). Retrospective review of ERGs in two independent groups of inbred (n = 15 and 537, respectively) and one group of outbred dogs (n = 36) was used to estimate CSNB frequency in these populations. {"Label"=>"RESULTS"} In the affected dog, there were absent dark-adapted b-waves in response to dim-light flashes, severely reduced dark-adapted b-waves in response to bright-light flashes, and normal light-adapted b-waves with a-waves that had broadened troughs. Long-flash ERGs confirmed a markedly reduced b-wave with a preserved d-wave, consistent with cone ON-bipolar cell dysfunction. There was evidence of normal rod photoreceptor a-wave dark adaptation, and rapid light adaptation. In the wider beagle populations, five inbred beagles had a b/a wave ratio of < 1 in dark-adapted bright-flash ERG, whereas no outbred beagles had ERGs consistent with CSNB. {"Label"=>"CONCLUSIONS"} The identified dog had clinical findings consistent with complete type CSNB, similar to that described in the Japanese colony. CSNB appears to be a rare disorder in the wider beagle population, although its detection could confound studies that use retinal function as an outcome measure in research dogs, necessitating careful baseline studies to be performed prior to experimentation.}, number={2}, journal={DOCUMENTA OPHTHALMOLOGICA}, author={Oh, Annie and Loew, Ellis R. and Foster, Melanie L. and Davidson, Michael G. and English, Robert V and Gervais, Kristen J. and Herring, Ian P. and Mowat, Freya M.}, year={2018}, month={Oct}, pages={87–101} }
 @article{dorman_foster_olesnevich_bolon_castel_sokolsky-papkov_mariani_2018, title={Toxicity associated with ingestion of a polyacrylic acid hydrogel dog pad}, volume={30}, ISSN={["1943-4936"]}, url={http://dx.doi.org/10.1177/1040638718782583}, DOI={10.1177/1040638718782583}, abstractNote={ Superabsorbent sodium polyacrylate polymeric hydrogels that retain large amounts of liquids are used in disposable diapers, sanitary napkins, and other applications. These polymers are generally considered “nontoxic” with acute oral median lethal doses (LD50) >5 g/kg. Despite this favorable toxicity profile, we identified a novel toxic syndrome in dogs and rats following the ingestion of a commercial dog pad composed primarily of a polyacrylic acid hydrogel. Inappropriate mentation, cerebellar ataxia, vomiting, and intention tremors were observed within 24 h after the ingestion of up to 15.7 g/kg of the hydrogel by an adult, castrated male Australian Shepherd mix. These observations prompted an experimental study in rats to further characterize the toxicity of the hydrogel. Adult, female Sprague Dawley rats ( n = 9) were assessed before and after hydrogel ingestion (2.6–19.2 g/kg over 4 h) using a functional observation battery and spontaneous motor activity. Clinical signs consistent with neurotoxicity emerged in rats as early as 2 h after the end of hydrogel exposure, including decreased activity in an open field, hunched posture, gait changes, reduced reaction to handling, decreased muscle tone, and abnormal surface righting. Hydrogel-exposed rats also had reduced motor activity when compared with pre-exposure baseline data. Rats that ingested the hydrogel did not develop nervous system lesions. These findings support the conclusion that some pet pad hydrogel products can induce acute neurotoxicity in animals under high-dose exposure conditions. }, number={5}, journal={JOURNAL OF VETERINARY DIAGNOSTIC INVESTIGATION}, author={Dorman, David C. and Foster, Melanie L. and Olesnevich, Brooke and Bolon, Brad and Castel, Aude and Sokolsky-Papkov, Marina and Mariani, Christopher L.}, year={2018}, month={Sep}, pages={708–714} }
 @article{dorman_foster_fernhoff_hess_2017, title={Canine scent detection of canine cancer: A feasibility study}, volume={8}, journal={Veterinary Medicine-Research and Reports}, author={Dorman, D. C. and Foster, M. L. and Fernhoff, K. E. and Hess, P. R.}, year={2017}, pages={1–7} }
 @article{fish_foster_gruen_sherman_dorman_2017, title={Effect of wearing a Telemetry jacket on behavioral and physiologic parameters of dogs in the open-field test}, volume={56}, number={4}, journal={Journal of the American Association for Laboratory Animal Science}, author={Fish, R. E. and Foster, M. L. and Gruen, M. E. and Sherman, B. L. and Dorman, D. C.}, year={2017}, pages={382–389} }
 @article{mercadante_herrera_pettiglio_foster_johnson_dorman_bartnikas_2016, title={The effect of high dose oral manganese exposure on copper, iron and zinc levels in rats}, volume={29}, ISSN={["1572-8773"]}, DOI={10.1007/s10534-016-9924-6}, abstractNote={Manganese is an essential dietary nutrient and trace element with important roles in mammalian development, metabolism, and antioxidant defense. In healthy individuals, gastrointestinal absorption and hepatobiliary excretion are tightly regulated to maintain systemic manganese concentrations at physiologic levels. Interactions of manganese with other essential metals following high dose ingestion are incompletely understood. We previously reported that gavage manganese exposure in rats resulted in higher tissue manganese concentrations when compared with equivalent dietary or drinking water manganese exposures. In this study, we performed follow-up evaluations to determine whether oral manganese exposure perturbs iron, copper, or zinc tissue concentrations. Rats were exposed to a control diet with 10 ppm manganese or dietary, drinking water, or gavage exposure to approximately 11.1 mg manganese/kg body weight/day for 7 or 61 exposure days. While manganese exposure affected levels of all metals, particularly in the frontal cortex and liver, copper levels were most prominently affected. This result suggests an under-appreciated effect of manganese exposure on copper homeostasis which may contribute to our understanding of the pathophysiology of manganese toxicity.}, number={3}, journal={BIOMETALS}, author={Mercadante, Courtney J. and Herrera, Carolina and Pettiglio, Michael A. and Foster, Melanie L. and Johnson, Laura C. and Dorman, David C. and Bartnikas, Thomas B.}, year={2016}, month={Jun}, pages={417–422} }
 @article{sherman_gruen_case_foster_fish_lazarowski_depuy_dorman_2015, title={A test for the evaluation of emotional reactivity in Labrador retrievers used for explosives detection}, volume={10}, ISSN={["1878-7517"]}, DOI={10.1016/j.jveb.2014.12.007}, abstractNote={The United States Marine Corps (USMC) uses Labrador retrievers as improvised explosive device detection dogs (IDDs). Of critical importance is the selection of dogs that are emotionally suited for this highly specialized application. The goal of our study was to develop an emotional reactivity test (ERT) as a screening tool for the selection of IDDs. The ERT included a series of subtasks that expose each dog sequentially to visual, auditory, and experiential stimuli with an associated grading scale used by trained observers to rate individual dog responses. In this study, 16 Labrador retrievers that met initial selection criteria as candidate IDDs were assessed using the ERT, measurement of plasma and salivary cortisol concentrations (pre- and post-ERT), and an independent open-field test of anxiety in response to sound stimuli. Based on the sum of its responses, each dog was assigned an aggregate ERT score. Aggregate ERT scores from independent trained observers were highly concordant [Shrout-Fleiss's intraclass correlation (2,1) = 0.96] suggesting excellent inter-rater reliability. The aggregate ERT scores were also negatively correlated with the dogs' scores on the open-field anxiety test (Spearman rank correlation, n = 16, r = −0.57, P = 0.0214). In addition, there were significant increases in salivary (Wilcoxon signed rank, n = 16, S = 38.5, P = 0.0458) and plasma (Wilcoxon signed rank, n = 16, S = 68, P < 0.0001) cortisol levels after the ERT, compared with baseline, suggesting that exposure to the ERT test elements produced a physiological stress response. We conclude that the ERT is a useful pre-training screening test that can be used to identify dogs with a low threshold of emotional reactivity for rejection, and dogs with a high threshold of emotional reactivity for entry into the IDD training program.}, number={2}, journal={JOURNAL OF VETERINARY BEHAVIOR-CLINICAL APPLICATIONS AND RESEARCH}, author={Sherman, Barbara L. and Gruen, Margaret E. and Case, Beth C. and Foster, Melanie L. and Fish, Richard E. and Lazarowski, Lucia and DePuy, Venita and Dorman, David C.}, year={2015}, pages={94–102} }
 @article{lazarowski_foster_gruen_sherman_fish_milgram_dorman_2015, title={Olfactory discrimination and generalization of ammonium nitrate and structurally related odorants in Labrador retrievers}, volume={18}, ISSN={1435-9448 1435-9456}, url={http://dx.doi.org/10.1007/s10071-015-0894-9}, DOI={10.1007/s10071-015-0894-9}, abstractNote={A critical aspect of canine explosive detection involves the animal's ability respond to novel, untrained odors based on prior experience with training odors. In the current study, adult Labrador retrievers (N = 15) were initially trained to discriminate between a rewarded odor (vanillin) and an unrewarded odor (ethanol) by manipulating scented objects with their nose in order to receive a food reward using a canine-adapted discrimination training apparatus. All dogs successfully learned this olfactory discrimination task (≥80 % correct in a mean of 296 trials). Next, dogs were trained on an ammonium nitrate (AN, NH4NO3) olfactory discrimination task [acquired in 60-240 trials, with a mean (±SEM) number of trials to criterion of 120.0 ± 15.6] and then tested for their ability to respond to untrained ammonium- and/or nitrate-containing chemicals as well as variants of AN compounds. Dogs did not respond to sodium nitrate or ammonium sulfate compounds at rates significantly higher than chance (58.8 ± 4.5 and 57.7 ± 3.3 % correct, respectively). Transfer performance to fertilizer-grade AN, AN mixed in Iraqi soil, and AN and flaked aluminum was significantly higher than chance (66.7 ± 3.2, 73.3 ± 4.0, 68.9 ± 4.0 % correct, respectively); however, substantial individual differences were observed. Only 53, 60, and 64 % of dogs had a correct response rate with fertilizer-grade AN, AN and Iraqi soil, and AN and flaked aluminum, respectively, that were greater than chance. Our results suggest that dogs do not readily generalize from AN to similar AN-based odorants at reliable levels desired for explosive detection dogs and that performance varies significantly within Labrador retrievers selected for an explosive detection program.}, number={6}, journal={Animal Cognition}, publisher={Springer Science and Business Media LLC}, author={Lazarowski, Lucia and Foster, Melanie L. and Gruen, Margaret E. and Sherman, Barbara L. and Fish, Richard E. and Milgram, Norton W. and Dorman, David C.}, year={2015}, month={Jul}, pages={1255–1265} }
 @article{dorman_foster_2015, title={Olfactory transport of manganese: Implications for neurotoxicity}, volume={22}, journal={Manganese in health and disease}, author={Dorman, D. C. and Foster, M. L.}, year={2015}, pages={119–132} }
 @article{foster_bartnikas_johnson_herrera_pettiglio_keene_taylor_dorman_2015, title={Pharmacokinetic Evaluation of the Equivalency of Gavage, Dietary, and Drinking Water Exposure to Manganese in F344 Rats}, volume={145}, ISSN={["1096-0929"]}, DOI={10.1093/toxsci/kfv047}, abstractNote={Concerns exist as to whether individuals may be at greater risk for neurotoxicity following increased manganese (Mn) oral intake. The goals of this study were to determine the equivalence of 3 methods of oral exposure and the rate (mg Mn/kg/day) of exposure. Adult male rats were allocated to control diet (10 ppm), high manganese diet (200 ppm), manganese-supplemented drinking water, and manganese gavage treatment groups. Animals in the drinking water and gavage groups were given the 10 ppm manganese diet and supplemented with manganese chloride (MnCl(2)) in drinking water or once-daily gavage to provide a daily manganese intake equivalent to that seen in the high-manganese diet group. No statistically significant difference in body weight gain or terminal body weights was seen. Rats were anesthetized following 7 and 61 exposure days, and samples of bile and blood were collected. Rats were then euthanized and striatum, olfactory bulb, frontal cortex, cerebellum, liver, spleen, and femur samples were collected for chemical analysis. Hematocrit was unaffected by manganese exposure. Liver and bile manganese concentrations were elevated in all treatment groups on day 61 (relative to controls). Increased cerebellum manganese concentrations were seen in animals from the high-manganese diet group (day 61, relative to controls). Increased (relative to all treatment groups) femur, striatum, cerebellum, frontal cortex, and olfactory bulb manganese concentrations were also seen following gavage suggesting that dose rate is an important factor in the pharmacokinetics of oral manganese. These data will be used to refine physiologically based pharmacokinetic models, extending their utility for manganese risk assessment by including multiple dietary exposures.}, number={2}, journal={TOXICOLOGICAL SCIENCES}, author={Foster, Melanie L. and Bartnikas, Thomas B. and Johnson, Laura C. and Herrera, Carolina and Pettiglio, Michael A. and Keene, Athena M. and Taylor, Michael D. and Dorman, David C.}, year={2015}, month={Jun}, pages={244–251} }
 @article{gruen_case_foster_lazarowski_fish_landsberg_depuy_dorman_sherman_2015, title={The use of an open-field model to assess sound-induced fear and anxiety-associated behaviors in Labrador retrievers}, volume={10}, ISSN={["1878-7517"]}, DOI={10.1016/j.jveb.2015.03.007}, abstractNote={Previous studies have shown that the playing of thunderstorm recordings during an open-field task elicits fearful or anxious responses in adult beagles. The goal of our study was to apply this open field test to assess sound-induced behaviors in Labrador retrievers drawn from a pool of candidate improvised explosive devices (IED)-detection dogs. Being robust to fear-inducing sounds and recovering quickly is a critical requirement of these military working dogs. This study presented male and female dogs, with 3 minutes of either ambient noise (Days 1, 3 and 5), recorded thunderstorm (Day 2), or gunfire (Day 4) sounds in an open field arena. Behavioral and physiological responses were assessed and compared to control (ambient noise) periods. An observer blinded to sound treatment analyzed video records of the 9-minute daily test sessions. Additional assessments included measurement of distance traveled (activity), heart rate, body temperature, and salivary cortisol concentrations. Overall, there was a decline in distance traveled and heart rate within each day and over the five-day test period, suggesting that dogs habituated to the open field arena. Behavioral postures and expressions were assessed using a standardized rubric to score behaviors linked to canine fear and anxiety. These fear/anxiety scores were used to evaluate changes in behaviors following exposure to a sound stressor. Compared to control periods, there was an overall increase in fear/anxiety scores during thunderstorm and gunfire sound stimuli treatment periods. Fear/anxiety scores were correlated with distance traveled, and heart rate. Fear/anxiety scores in response to thunderstorm and gunfire were correlated. Dogs showed higher fear/anxiety scores during periods after the sound stimuli compared to control periods. In general, candidate IED-detection Labrador retrievers responded to sound stimuli and recovered quickly, although dogs stratified in their response to sound stimuli. Some dogs were robust to fear/anxiety responses. The results suggest that the open field sound test may be a useful method to evaluate the suitability of dogs for IED-detection training.}, number={4}, journal={JOURNAL OF VETERINARY BEHAVIOR-CLINICAL APPLICATIONS AND RESEARCH}, author={Gruen, Margaret E. and Case, Beth C. and Foster, Melanie L. and Lazarowski, Lucia and Fish, Richard E. and Landsberg, Gary and Depuy, Venita and Dorman, David C. and Sherman, Barbara L.}, year={2015}, pages={338–345} }
 @article{lazarowski_foster_gruen_sherman_case_fish_milgram_dorman_2014, title={Acquisition of a visual discrimination and reversal learning task by Labrador retrievers}, volume={17}, ISSN={["1435-9456"]}, DOI={10.1007/s10071-013-0712-1}, abstractNote={Optimal cognitive ability is likely important for military working dogs (MWD) trained to detect explosives. An assessment of a dog’s ability to rapidly learn discriminations might be useful in the MWD selection process. In this study, visual discrimination and reversal tasks were used to assess cognitive performance in Labrador retrievers selected for an explosives detection program using a modified version of the Toronto General Testing Apparatus (TGTA), a system developed for assessing performance in a battery of neuropsychological tests in canines. The results of the current study revealed that, as previously found with beagles tested using the TGTA, Labrador retrievers (N = 16) readily acquired both tasks and learned the discrimination task significantly faster than the reversal task. The present study confirmed that the modified TGTA system is suitable for cognitive evaluations in Labrador retriever MWDs and can be used to further explore effects of sex, phenotype, age, and other factors in relation to canine cognition and learning, and may provide an additional screening tool for MWD selection.}, number={3}, journal={ANIMAL COGNITION}, author={Lazarowski, Lucia and Foster, Melanie L. and Gruen, Margaret E. and Sherman, Barbara L. and Case, Beth C. and Fish, Richard E. and Milgram, Norton W. and Dorman, David C.}, year={2014}, month={May}, pages={787–792} }
 @article{taylor_foster_law_centeno_fornero_henderson_trager_stockelman_dorman_2013, title={Assessment of geographical variation in the respiratory toxicity of desert dust particles}, volume={25}, ISSN={["0895-8378"]}, DOI={10.3109/08958378.2013.797524}, abstractNote={Abstract The health consequences of sand particle inhalation are incompletely understood. This project evaluated the respiratory toxicity of sand particles collected at military bases near Fort Irwin USA, in Iraq (Camp Victory, Taji and Talil), and Khost Afghanistan. Our primary focus was on assessing the role of soluble metals in the respiratory toxicity of the sand particles using in vitro and in vivo methods. Replicating rat type II alveolar cell cultures (RLE-6TN) were exposed to sand extracts or vehicle control in serum-free media for ≤24 h. Cytotoxicity was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and assessment of lactate dehydrogenase leakage. The relative in vitro cytotoxicity of the sand extracts was Taji ≈ Talil > Afghanistan > Camp Victory ≈ Fort Irwin. We also assessed extracts of Camp Victory, Afghanistan, and Taji sand for acute and delayed pulmonary toxicity in rats following intratracheal administration. Assessments included biochemical analysis of bronchoalveolar lavage fluid (BALF) and lung histopathology. The in vitro cytotoxicity assay results were partially predictive of in vivo responses. The more cytotoxic Taji sand extract induced an acute irritant response in rats following intratracheal administration. Rats given the less cytotoxic Camp Victory sand extract had minimal biochemical or cytological BALF changes whereas rats given either the Afghanistan or Taji sand extracts demonstrated BALF changes that were suggestive of mild lung inflammation. Unexpectedly, we observed similar lung pathology in all extract-exposed rats. The results of our study can be used to prioritize future particle inhalation studies or guide epidemiological study design.}, number={7}, journal={INHALATION TOXICOLOGY}, author={Taylor, Karen and Foster, Melanie L. and Law, J. McHugh and Centeno, Jose A. and Fornero, Elisa and Henderson, M. Stephen and Trager, Sabrina A. and Stockelman, Michael G. and Dorman, David C.}, year={2013}, month={Jun}, pages={405–416} }
 @article{schroeter_kimbell_asgharian_tewksbury_sochaski_foster_dorman_wong_andersen_2013, title={Inhalation dosimetry of hexamethylene diisocyanate vapor in the rat and human respiratory tracts}, volume={25}, ISSN={["1091-7691"]}, DOI={10.3109/08958378.2013.768314}, abstractNote={Hexamethylene diisocyanate (HDI) is a reactive chemical used in the commercial production of polyurethanes. Toxic effects in rodents exposed to HDI vapor primarily occur in the nasal passages, yet some individuals exposed occupationally to concentrations exceeding current regulatory limits may experience temporary reduction in lung function and asthma-like symptoms. Knowledge of interspecies differences in respiratory tract dosimetry of inhaled HDI would improve our understanding of human health risks to this compound. HDI uptake was measured in the upper respiratory tract of anesthetized Fischer-344 rats. Nasal uptake of HDI was >90% in rats at unidirectional flow rates of 150 and 300 ml/min and a target air concentration of 200 ppb. Uptake data was used to calibrate nasal and lung dosimetry models of HDI absorption in rats and humans. Computational fluid dynamics (CFD) models of the nasal passages were used to simulate inspiratory airflow and HDI absorption. Transport of HDI through lung airways was simulated using convection-diffusion based mass transport models. HDI nasal uptake of 90% and 78% was predicted using the rat and human nasal CFD models, respectively. Total respiratory tract uptake was estimated to be 99% in rats and 97% in humans under nasal breathing. Predicted human respiratory uptake decreased to 87% under oral breathing conditions. Absorption rates of inhaled HDI in human lung airways were estimated to be higher than the rat due to lower uptake in head airways. Model predictions demonstrated significant penetration of HDI to human bronchial airways, although absorption rates were sensitive to breathing style.}, number={3}, journal={INHALATION TOXICOLOGY}, author={Schroeter, Jeffry D. and Kimbell, Julia S. and Asgharian, Bahman and Tewksbury, Earl W. and Sochaski, Mark and Foster, Melanie L. and Dorman, David C. and Wong, Brian A. and Andersen, Melvin E.}, year={2013}, month={Feb}, pages={168–177} }