Effects of Fluorescent Lighting Versus Sunlight Exposure on Calcium, Magnesium, Vitamin D, and Feather Destructive Behavior in Hispaniolan Amazon Parrots (Amazona ventralis).

Low exposure to ultraviolet light, and resulting vitamin D deficiency, has recently been linked to autism spectrum disorder in people. Captive psittacine birds that exhibit feather destructive behavior share similarities with people affected by autism spectrum disorder, such as repetitive (stereotypies) and self-harming behaviors. The metabolic and psychological effects of housing pet parrots indoors without ultraviolet B lighting are not typically considered in animal husbandry or veterinary care. Calcifediol (serum vitamin D), ionized calcium, and ionized magnesium levels were compared between 10 Hispaniolan Amazon parrots (Amazona ventralis) housed indoors and 10 Hispaniolan Amazon parrots historically housed outdoors. Although ionized calcium and magnesium levels were not significantly different, calcifediol levels were significantly greater in the colony of birds housed outdoors. Further, these 2 research colonies of individually housed birds were feather scored. Subjectively, the birds that were housed indoors had greater self-inflicted feather damage than did those housed outdoors; however, the difference was not statistically significant.

An Indirect Indentation Method for Evaluating the Linear Viscoelastic Properties of the Brain Tissue.

Indentation experiments offer a robust, fast, and repeatable testing method for evaluating the mechanical properties of the solid-state materials in a wide stiffness range. With the advantage of requiring a minimal sample preparation and multiple tests on a small piece of specimen, this method has recently become a popular technique for measuring the elastic properties of the biological materials, especially the brain tissue whose ultrasoft nature makes its mechanical characterization very challenging. Nevertheless, some limitations are associated with the indentation of the brain tissue, such as improper surface detection, negative initial contact force due to tip-tissue moisture interaction, and partial contact between the tip and the sample. In this study, an indirect indentation scheme is proposed to overcome the aforementioned difficulties. In this way, the indentation force is transferred from a sharp tip to the surface of the tissue slices via a rigid coverslip. To demonstrate the accuracy of this method, the linear viscoelastic properties of the white and gray matters of the bovine brain samples are measured by imposing small cyclic loads at different frequencies. The rate, regional, directional, and postmortem time dependence of the viscoelastic moduli are investigated and compared with the previous results from cyclic shear and monotonic experiments on the brain tissue. While findings of this research present a comprehensive set of information for the viscoelastic properties of the brain at a wide frequency range, the central goal of this paper is to introduce a novel experimentation technique with noticeable advantages for biomechanical characterization of the soft tissue.

Cytotoxic and antiangiogenic paclitaxel solubilized and permeation-enhanced by natural product nanoparticles.

Paclitaxel (PTX) is one of the most potent intravenous chemotherapeutic agents to date, yet an oral formulation has been problematic because of its low solubility and permeability. Using the recently discovered solubilizing properties of rubusoside (RUB), we investigated the unique PTX-RUB formulation. PTX was solubilized by RUB in water to levels of 1.6-6.3 mg/ml at 10-40% weight/volume. These nanomicellar PTX-RUB complexes were dried to a powder, which was subsequently reconstituted in physiologic solutions. After 2.5 h, 85-99% of PTX-RUB remained soluble in gastric fluid, whereas 79-96% remained soluble in intestinal fluid. The solubilization of PTX was mechanized by the formation of water-soluble spherical nanomicelles between PTX and RUB, with an average diameter of 6.6 nm. Compared with Taxol, PTX-RUB nanoparticles were nearly four times more permeable in Caco-2 cell monocultures. In a side-by-side comparison with dimethyl sulfoxide-solubilized PTX, PTX-RUB maintained the same level of cytotoxicity against three human cancer cell lines with IC50 values ranging from 4 to 20 nmol/l. In addition, tubule formation and migration of human umbilical vein endothelial cells were inhibited at levels as low as 5 nmol/l. These chemical and biological properties demonstrated by the PTX-RUB nanoparticles may improve oral bioavailability and enable further pharmacokinetic, toxicologic, and efficacy investigations.

Hepatitis E antibodies in laboratory rabbits from 2 US vendors.

We tested laboratory rabbits from 2 US vendors for antibodies against hepatitis E virus (HEV); Seroprevalences were 40% and 50%. Retrospective analysis of an ocular herpes simplex 1 experiment demonstrated that HEV seropositivity had no effect on experiment outcome. HEV probably is widespread in research rabbits, but effects on research remain unknown.

A Quadruple Gene-Deleted Live BoHV-1 Subunit RVFV Vaccine Vector Reactivates from Latency and Replicates in the TG Neurons of Calves but Is Not Transported to and Shed from Nasal Mucosa.

Bovine herpesvirus type 1 (BoHV-1) establishes lifelong latency in trigeminal ganglionic (TG) neurons following intranasal and ocular infection in cattle. Periodically, the latent virus reactivates in the TG due to stress and is transported anterogradely to nerve endings in the nasal epithelium, where the virus replicates and sheds. Consequently, BoHV-1 is transmitted to susceptible animals and maintained in the cattle population. Modified live BoHV-1 vaccine strains (BoHV-1 MLV) also have a similar latency reactivation. Therefore, they circulate and are maintained in cattle herds. Additionally, they can regain virulence and cause vaccine outbreaks because they mutate and recombine with other circulating field wild-type (wt) strains. Recently, we constructed a BoHV-1 quadruple mutant virus (BoHV-1qmv) that lacks immune evasive properties due to UL49.5 and glycoprotein G (gG) deletions. In addition, it also lacks the gE cytoplasmic tail (gE CT) and Us9 gene sequences designed to make it safe, increase its vaccine efficacy against BoHV-1, and restrict its anterograde neuronal transport noted above. Further, we engineered the BoHV-1qmv-vector to serve as a subunit vaccine against the Rift Valley fever virus (BoHV-1qmv Sub-RVFV) (doi: 10.3390/v15112183). In this study, we determined the latency reactivation and nasal virus shedding properties of BoHV-1qmv (vector) and BoHV-1qmv-vectored subunit RVFV (BoHV-1qmv sub-RVFV) vaccine virus in calves in comparison to the BoHV-1 wild-type (wt) following intranasal inoculation. The real-time PCR results showed that BoHV-1 wt- but not the BoHV-1qmv vector- and BoHV-1qmv Sub-RVFV-inoculated calves shed virus in the nose following dexamethasone-induced latency reactivation; however, like the BoHV-1 wt, both the BoHV-1qmv vector and BoHV-1qmv Sub-RVFV viruses established latency, were reactivated, and replicated in the TG neurons. These results are consistent with the anterograde neurotransport function of the gE CT and Us9 sequences, which are deleted in the BoHV-1qmv and BoHV-1qmv Sub-RVFV.

Solubilization of Paclitaxel with Natural Compound Rubusoside toward Improving Oral Bioavailability in a Rodent Model.

Paclitaxel, which features low water solubility and permeability, is an efflux pump substrate. The current paclitaxel drugs are given intravenously after resolving the solubility issue. Yet, oral delivery to achieve therapeutic bioavailability is not effective due to low absorption. This study evaluated a natural compound, rubusoside, to improve oral bioavailability in an animal model. Free paclitaxel molecules were processed into nano-micelles formed in water with rubusoside. The particle size of the nano-micelles in water was determined using dynamic light scattering. The oral bioavailability of paclitaxel in nano-micelles was determined against Cremophor/alcohol-solubilized Taxol after oral and intravenous administration to pre-cannulated Sprague Dawley rats. When loaded into the rubusoside-formed nano-micelles, paclitaxel reached a supersaturated concentration of 6 mg/mL, 60,000-fold over its intrinsic saturation of 0.1 µg/mL. The mean particle size was 4.7 ± 0.7 nm in diameter. Compared with Taxol®, maximum blood concentration was increased by 1.5-fold; the time to reach maximum concentration shortened to 0.8 h from 1.7 h; and, relative oral bioavailability increased by 88%. Absolute oral bioavailability was 1.7% and 1.3% for the paclitaxel nano-micelles and Taxol®, respectively. Solubilizing paclitaxel with rubusoside was successful, but oral bioavailability remained low. Further inhibition of the efflux pump and/or first metabolism may allow more oral paclitaxel to enter systemic circulation.

The impact of lutein-loaded poly(lactic-co-glycolic acid) nanoparticles following topical application: An in vitro and in vivo study.

Antioxidant therapies are of interest in the prevention and management of ocular disorders such as cataracts. Although an active area of interest, topical therapy with antioxidants for the treatment of cataracts is complicated by multiple ocular anatomical barriers, product stability, and solubility. Entrapment and delivery of antioxidants with poly(lactic-co-glycolic acid) nanoparticles is a possible solution to these challenges, however, little is known regarding their effects in vitro or in vivo. Our first aim was to investigate the impact of blank and lutein loaded PLGA nanoparticles on viability and development of reactive oxygen species in lens epithelial cells in vitro. Photo-oxidative stress was induced by ultraviolet light exposure with cell viability and reactive oxygen species monitored. Next, an in vivo, selenite model was utilized to induce cataract formation in rodents. Eyes were treated topically with both free lutein and lutein loaded nanoparticles (LNP) at varying concentrations. Eyes were monitored for the development of anterior segment changes and cataract formation. The ability of nanodelivered lutein to reach the anterior segment of the eye was evaluated by liquid chromatography coupled to mass spectrometry of aqueous humor samples and liquid chromatography coupled to tandem mass spectrometry (targeted LC-MS/MS) of lenses. LNP had a minimal impact on the viability of lens epithelial cells during the short exposure timeframe (24 h) and at concentrations < 0.2 µg LNP/µl. A significant reduction in the development of reactive oxygen species was also noted. Animals treated with LNPs at an equivalent lutein concentration of 1,278 µg /mL showed the greatest reduction in cataract scores. Lutein delivery to the anterior segment was confirmed through evaluation of aqueous humor and lens sample evaluation. Topical treatment was not associated with the development of secondary keratitis or anterior uveitis when applied once daily for one week. LNPs may be an effective in the treatment of cataracts.

Live Triple Gene-Deleted Pseudorabies Virus-Vectored Subunit PCV2b and CSFV Vaccine Undergoes an Abortive Replication Cycle in the TG Neurons following Latency Reactivation.

Like other alpha herpesviruses, pseudorabies virus (PRV) establishes lifelong latency in trigeminal ganglionic (TG) neurons. Upon stress, the latent viruses in the TG neurons reactivate and are transported anterograde from the neuron cell bodies to the nerve endings in the nasal mucosa, where they replicate and are discharged in the nasal and oral secretions. Consequently, the virus is transmitted to other naïve animals. This cycle of latency and reactivation continues until the animal dies or is slaughtered. We have constructed a PRV triple mutant virus (PRVtmv) and used it as a live subunit vaccine vector against porcine circovirus 2b (PCV2b) and classical swine fever virus (CSFV) (PRVtmv+). We compared the latency reactivation properties of PRVtmv+ with its parent wild-type (wt) Becker strain following intranasal infection. The results showed that PRV wt and PRVtmv+ established latency in the TG neurons. Based on nasal virus shedding, immediate early (infected cell protein 0; ICP0) and late genes, MCP (major capsid protein) and gC (glycoprotein C) transcriptions, and viral DNA copy numbers in the TGs of latently infected and dexamethasone (Dex)-treated pigs, both PRV wt and PRVtmv+ reactivated from latency. We noticed that PRV wt virus replicated productively in the terminally differentiated, postmitotic TG neurons, but PRVtmv+ failed to replicate and, therefore, there was no virus production in the TG. In addition, we found that only the PRV wt virus was shed in the nasal secretions following the Dex-induced reactivation. Our results demonstrated that the PRVtmv+ is safe as a live viral subunit vaccine vector without the possibility of productive replication in the TG upon reactivation from latency and without subsequent nasal virus shedding. This property of PRVtmv+ precludes the possibility of vaccine virus circulation in pigs and the risk of reversion to virulence.

A Novel Quadruple Gene-Deleted BoHV-1-Vectored RVFV Subunit Vaccine Induces Humoral and Cell-Mediated Immune Response against Rift Valley Fever in Calves.

Rift Valley fever virus (RVFV) is considered to be a high biodefense priority based on its threat to livestock and its ability to cause human hemorrhagic fever. RVFV-infected livestock are also a significant risk factor for human infection by direct contact with contaminated blood, tissues, and aborted fetal materials. Therefore, livestock vaccination in the affected regions has the direct dual benefit and one-health approach of protecting the lives of millions of animals and eliminating the risk of severe and sometimes lethal human Rift Valley fever (RVF) disease. Recently, we have developed a bovine herpesvirus type 1 (BoHV-1) quadruple gene mutant virus (BoHV-1qmv) vector that lacks virulence and immunosuppressive properties due to the deletion of envelope proteins UL49.5, glycoprotein G (gG), gE cytoplasmic tail, and US9 coding sequences. In the current study, we engineered the BoHV-1qmv further by incorporating a chimeric gene sequence to express a proteolytically cleavable polyprotein: RVFV envelope proteins Gn ectodomain sequence fused with bovine granulocyte-macrophage colony-stimulating factor (GMCSF) and Gc, resulting in a live BoHV-1qmv-vectored subunit vaccine against RVFV for livestock. In vitro, the resulting recombinant virus, BoHV-1qmv Sub-RVFV, was replicated in cell culture with high titers. The chimeric Gn-GMCSF and Gc proteins expressed by the vaccine virus formed the Gn-Gc complex. In calves, the BoHV-1qmv Sub-RVFV vaccination was safe and induced moderate levels of the RVFV vaccine strain, MP12-specific neutralizing antibody titers. Additionally, the peripheral blood mononuclear cells from the vaccinated calves had six-fold increased levels of interferon-gamma transcription compared with that of the BoHV-1qmv (vector)-vaccinated calves when stimulated with heat-inactivated MP12 antigen in vitro. Based on these findings, we believe that a single dose of BoHV-1qmv Sub-RVFV vaccine generated a protective RVFV-MP12-specific humoral and cellular immune response. Therefore, the BoHV-1qmv sub-RVFV can potentially be a protective subunit vaccine for cattle against RVFV.

Effects of fenbendazole on fecal microbiome in BPH/5 mice, a model of hypertension and obesity, a brief report.

Fenbendazole (FBZ) is a common antiparasitic treatment used in research rodent colonies for biosecurity purposes. The effect of this compound has been studied in C57 mice, but never before in a strain of mice that has co-morbidities, such as the blood pressure high (BPH)/5. The BPH/5 mouse is an inbred genetic model of hypertension. While both male and female BPH/5 have high blood pressure, there is a metabolic sexual dimorphism with females displaying key features of obesity. The obese gut microbiome has been linked to hypertension. Therefore, we hypothesized that fenbendazole treatment will alter the gut microbiome in hypertensive mice in a sex dependent manner. To test the influence of FBZ on the BPH/5 gut microbiota, fecal samples were collected pre- and post-treatment from adult BPH/5 mice (males and non-pregnant females). The mice were treated with fenbendazole impregnated feed for five weeks. Post-treatment feces were collected at the end of the treatment period and DNA was extracted, and the V4 region of 16S rRNA was amplified and sequenced using the Illumina MiSeq system. The purpose was to analyze the fecal microbiome before and after FBZ treatment, the results demonstrate changes with treatment in a sex dependent manner. More specifically, differences in community composition were detected in BPH/5 non-pregnant female and males using Bray-Curtis dissimilarity as a measure of beta-diversity (treatment p = 0.002). The ratio of Firmicutes to Bacteroidetes, which has been identified in cases of obesity, was not altered. Yet, Verrucomicrobia was increased in BPH/5 males and females post-treatment and was significantly different by sex (treatment p = 5.85e-05, sex p = 0.0151, and interaction p = 0.045), while Actinobacteria was decreased in the post-treatment mice (treatment p = 0.00017, sex p = 0.5, interaction p = 0.2). These results are indicative of gut dysbiosis compared to pre-treatment controls. Lactobacillus was decreased with FBZ treatment in BPH/5 females only. In conclusion, fenbendazole does alter the gut microbial communities, most notable in the male rather than female BPH/5 mouse. This provides evidence that caution should be taken when providing any gut altering treatments before or during mouse experiments.

Plasma Vitamin D (25-Hydroxyvitamin D) Levels in Hispaniolan Amazon Parrots (Amazona ventralis) Housed Indoors Over Time.

Vitamin D is a hormone that can be ingested or synthesized in the body when skin is exposed to ultraviolet radiation (UV), typically from sunlight. In captivity, birds with no sunlight exposure may develop vitamin D deficiencies that may contribute to hypocalcemic conditions, even when fed a diet supplemented with vitamin D. An initial pilot study with Hispaniolan Amazon parrots (Amazona ventralis) conducted approximately 18 mo prior indicated there were significant differences in the 25-hydroxyvitamin D (vit D) plasma levels between the resident parrots (indoor-only housing) and a new group of historically outdoor-housed parrots (new parrots) 5 days after the arrival of the latter at our institution. The goals of this study were to determine if vit D, ionized calcium (Ca2+), and ionized magnesium (Mg2+) levels changed from baseline values (taken 18 mo prior) in the new birds as well as to compare those values to those of the resident birds over time. The treatment was a change in husbandry for the new parrots (no UV exposure and diet as provided for the resident parrots). To accomplish this, the authors compared vit D levels in the same two groups of birds that were fed the same vit D-fortified diet and given no access to natural or artificial UV light exposure for 18 mo. The resident parrots (N = 9) had been housed indoors for approximately 20 yr with no exposure to natural or supplemented UV light. The second group of birds (new parrots; N = 8) had been housed outdoors prior to the initiation of the pilot study in 2016 and were fed a similar-but not identical-diet prior to their arrival. Plasma samples were sent to the Michigan State University Diagnostic Center for Population and Animal Health for analysis. Test results demonstrated differences between the two groups of parrots, largely attributed to the decrease in vit D plasma levels in the new parrots over time to values equivalent to those measured in the resident birds. Differences were seen in plasma Ca2+, while no differences were demonstrated relative to Mg2+. We discuss these findings and suggest that plasma vit D levels decrease in the absence of UV light, even when animals are maintained on a vit D-fortified and balanced diet.

A Triple Gene-Deleted Pseudorabies Virus-Vectored Subunit PCV2b and CSFV Vaccine Protects Pigs against PCV2b Challenge and Induces Serum Neutralizing Antibody Response against CSFV.

Porcine circovirus type 2 (PCV2) is endemic worldwide. PCV2 causes immunosuppressive infection. Co-infection of pigs with other swine viruses, such as pseudorabies virus (PRV) and classical swine fever virus (CSFV), have fatal outcomes, causing the swine industry significant economic losses in many if not all pig-producing countries. Currently available inactivated/modified-live/vectored vaccines against PCV2/CSFV/PRV have safety and efficacy limitations. To address these shortcomings, we have constructed a triple gene (thymidine kinase, glycoprotein E [gE], and gG)-deleted (PRVtmv) vaccine vector expressing chimeric PCV2b-capsid, CSFV-E2, and chimeric Erns-fused with bovine granulocytic monocyte-colony stimulating factor (Erns-GM-CSF), designated as PRVtmv+, a trivalent vaccine. Here we compared this vaccine's immunogenicity and protective efficacy in pigs against wild-type PCV2b challenge with that of the inactivated Zoetis Fostera Gold PCV commercial vaccine. The live PRVtmv+ prototype trivalent subunit vaccine is safe and highly attenuated in pigs. Based on PCV2b-specific neutralizing antibody titers, viremia, viral load in lymphoid tissues, fecal-virus shedding, and leukocyte/lymphocyte count, the PRVtmv+ yielded better protection for vaccinated pigs than the commercial vaccine after the PCV2b challenge. Additionally, the PRVtmv+ vaccinated pigs generated low to moderate levels of CSFV-specific neutralizing antibodies.

BoHV-1-Vectored BVDV-2 Subunit Vaccine Induces BVDV Cross-Reactive Cellular Immune Responses and Protects against BVDV-2 Challenge.

The bovine respiratory disease complex (BRDC) remains a major problem for both beef and dairy cattle industries worldwide. BRDC frequently involves an initial viral respiratory infection resulting in immunosuppression, which creates a favorable condition for fatal secondary bacterial infection. Current polyvalent modified live vaccines against bovine herpesvirus type 1(BoHV-1) and bovine viral diarrhea virus (BVDV) have limitations concerning their safety and efficacy. To address these shortcomings and safety issues, we have constructed a quadruple gene mutated BoHV-1 vaccine vector (BoHV-1 QMV), which expresses BVDV type 2, chimeric E2 and Flag-tagged Erns-fused with bovine granulocyte monocyte colony-stimulating factor (GM-CSF) designated here as QMV-BVD2*. Here we compared the safety, immunogenicity, and protective efficacy of QMV-BVD2* vaccination in calves against BVDV-2 with Zoetis Bovi-shield Gold 3 trivalent (BoHV-1, BVDV types 1 and 2) vaccine. The QMV-BVD2* prototype subunit vaccine induced the BoHV-1 and BVDV-2 neutralizing antibody responses along with BVDV-1 and -2 cross-reactive cellular immune responses. Moreover, after a virulent BVDV-2 challenge, the QMV-BVD2* prototype subunit vaccine conferred a more rapid recall BVDV-2-specific neutralizing antibody response and considerably better recall BVDV types 1 and 2-cross protective cellular immune responses than that of the Zoetis Bovi-shield Gold 3.

Gut Microbiota Composition and Predicted Microbial Metabolic Pathways of Obesity Prone and Obesity Resistant Outbred Sprague-Dawley CD Rats May Account for Differences in Their Phenotype.

Like humans, outbred Sprague-Dawley CD rats exhibit a polygenic pattern of inheritance of the obese phenotype and not all individuals exposed to a high calorie intake develop obesity. We hypothesized that differences in gut microbiota composition account for phenotype differences between obese prone (OP) and obese resistant (OR) rats. We studied the gut microbiota composition of OPand OR rats after a high fat (HF) diet and how they respond to fermentation of resistant starch (RS). In phase 1 of the study 28 OP and 28 OR rats were fed a HF diet. In order to determine causal role of microbiota on phenotypes, In phase 2, a microbiota transplant between the two phenotypes was performed before switching all rats to a HF diet supplemented with 20% RS. We determined microbiota composition by 16S sequencing and predicted microbiota function by PICRUSt2. Despite a similar calorie intake, in phase 2 OP rats gained more weight and accumulated more abdominal fat in both phase 1 and 2 compared to OR rats (P < 0.001; n = 6). The OP rats fermented RS more robustly compared with OR rats with an increase in total bacteria, short chain fatty acids, and increased weight of the cecum, but microbiota of OP rats had much lower alpha diversity and evenness. The microbiota of OP rats, had higher amounts of bacteria from order Bacteroidales, specifically family Muribaculaceae (S24-7), which is known to possess several starch degrading enzymes and was reported in previous studies to increase with fermentation of RS. The OR rats fermented RS less but had higher bacterial diversity and evenness and had significantly higher bacterial counts from phylum Firmicutes particularly order Clostridiales, genus Clostridium and an uncultured bacterium of the genus Akkermansia. The microbiota of OR rats had enhanced bacterial chemotaxis, phosphotransferase system (PTS), and fatty acid biosynthesis compared to OP rats whose microbiota had higher glycan degradation and LPS biosynthesis pathways. The microbiota transplant did not change obesity phenotype or microbiota composition. In conclusion, a higher alpha-diversity and evenness of the microbiota and higher proportions of Clostridiales and Akkermansia in OR rats were associated with a better metabolic phenotype with lower body fat. However, robust RS fermentation caused a lower diversity and evenness and did not result in a leaner phenotype.

Variability associated with repeated measurements of gastrointestinal tract motility in dogs obtained by use of a wireless motility capsule system and scintigraphy.

OBJECTIVE: To compare repeatability of measurements of gastrointestinal tract motility in healthy dogs obtained by use of a wireless motility capsule (WMC) and scintigraphy. ANIMALS: 6 healthy adult dogs (mean +/- SD body weight, 21.5 +/- 1.8 kg). PROCEDURES: A radiolabeled test meal was offered immediately after oral administration of a WMC. Serial static scintigraphic abdominal images were acquired for 270 minutes. A dedicated remote receiver was used for data collection from the WMC until the WMC was expelled in the feces. Each dog was evaluated 3 times at intervals of 1 to 2 weeks. RESULTS: Mean gastric emptying half-time measured by use of scintigraphy (T(1/2)-GES) for each dog ranged from 99.9 to 181.2 minutes. Mean gastric emptying time (GET) measured by use of the WMC (GET-WMC) in each dog ranged from 385.3 to 669.7 minutes. Mean coefficient of variation was 11.8% for T(1/2)-GES and 7.8% for GET-WMC. The intraclass correlation coefficient was 69% for T(1/2)-GES and 71% for GET-WMC. Results for a nested analysis of covariance suggested that both methods were comparable for the evaluation of gastric emptying. CONCLUSIONS AND CLINICAL RELEVANCE: Scintigraphy and a WMC system had similar variation for assessment of gastric emptying. Moderate intraindividual variability was detected for both methods and must be considered when interpreting test results for individual dogs. Repeatability of measurements obtained by use of the WMC was equivalent to that obtained by use of scintigraphy. The WMC system offers a nonradioactive, user-friendly method for assessment of gastric emptying in dogs.

Association of Chronic Myelogenous (Basophilic) Leukemia and the BCR/ABL Mutation in a Yucatan Barrow (Sus scrofa domestica).

Background: Chronic myelogenous leukemia (CML) is a clonal proliferative disorder of the myeloid, megakaryocyte, and erythroid lineages. The onset and subsequent progression of CML is well-described in humans. There is comparably little information surrounding CML progression in veterinary species, including Yucatan miniature swine that are common for preclinical pharmaceutical and device testing. In humans, more than 90% of CML cases are associated with a chromosomal translocation that results in the Philadelphia gene (BCR/ABL mutation). In this report, the presence of the Philadelphia gene in a Yucatan burrow was confirmed in white blood cells collected prior to onset of clinical signs with primers designed from the human BCR/ABL sequence. Case Presentation: A 24 month old, 70 kg, Yucatan barrow received a prefabricated bovine cortical bone xenograft following a unilateral zygomatic ostectomy for a preclinical study. Complete blood count and serum chemistries were performed prior to and 28, 53, 106, and 129 days after facial surgery. Fifty three days after surgery, a bone marrow biopsy was performed due to anorexia, severe basophilia, and mild anemia. A finding of a moderate increase in basophilic precursors in bone marrow cytology was followed by lymphocyte immunophenotyping via flow cytometry and RT-PCR amplification of the Philadelphia gene in white blood cell samples from the affected barrow and an unaffected barrow in the same treatment group. Bone marrow, lymph node, liver, spleen, lung, kidney, and adrenal gland lesions of mostly myeloblasts were identified after the affected barrow died 146 days after surgery. Flow cytometry confirmed lymphopenia and suggested basophilia, and RT-PCR established the presence of the BCR/ABL gene. Conclusions: The information in this report confirms the presence of the BCR/ABL mutation and documents progression of chronic myelogenous (basophilic) leukemia from a chronic phase to a terminal blast crisis in an adult Yucatan barrow. The natural occurrence and progression of CML associated with the BCR/ABL mutation in miniature swine establishes potential for future porcine models of human CML. The information also establishes a genetic test to confirm porcine CML to prevent inadvertent attribution of clinical signs to treatment complications during preclinical testing.

Abundance of the species Clostridium butyricum in the gut microbiota contributes to differences in obesity phenotype in outbred Sprague-Dawley CD rats.

OBJECTIVES: Gut microbiota profiles contribute to differences in obesity phenotype. We examined the abundance of the species Clostridium butyricum in relation to obesity phenotype. METHODS: In outbred Sprague -Dawley rats we examined effects of dietary fat, resistant starch (RS), and a microbiota transplant on obesity phenotype. Using targeted qPCR, we examined the abundance of total gut bacteria and C. butyricum in relation to the propensity of obesity prone and obesity resistant rats to accumulate abdominal fat. RESULTS: Before inclusion of dietary RS, obesity resistant (OR) rats had higher amounts of total bacteria, and C. butyricum compared to obesity prone (OP) rats (P < 0.005 in study I, P < 0.0001 in study II). A high fat diet (HF) lowered C. butyricum levels while RS had no effect. Dietary RS elicited robust fermentation and increased total bacteria only in OP rats. In preparation for the transplant, antibiotics were administered to recipient rats. Four weeks thereafter, total bacteria levels were restored but, C. butyricum levels were not. The transplant between the two phenotypes had no effect on abundance of C. butyricum and obesity phenotype. CONCLUSIONS: While C. butyricum is a known saccharolytic, its proliferation is not enhanced by fermentation of resistant starch. C. butyricum maybe one of the species that constitute a core microbiota involved in energy storage and metabolism through mechanisms that are not yet known.

A combined experimental, modeling, and computational approach to interpret the viscoelastic response of the white matter brain tissue during indentation.

Viscoelastic properties of the white matter brain tissue are systematically studied in this paper utilizing indentation experiments, mathematical modeling, and finite element simulation. It is first demonstrated that the internal stiffness of the instrument needs to be thoroughly obtained and incorporated in the analysis as its contribution to the recorded mechanical response is significant for experiments on very compliant materials. The flat-punch monotonic indentation is then performed indirectly on sagittal plane slices with pushing a large rigid coverslip into the sample surface. The recorded load and displacement data are used for calibrating different viscoelastic models and presenting numerical values for the model elements. Consequently, the accuracy of the findings based on the theoretical models is investigated by performing finite element simulations which suggest a considerable substrate effect that causes violation of the semi-infinite half-space assumption in modeling of the material behavior. Accordingly, correction factors for adjusting the viscoelastic constants are obtained and presented. Since the Maxwell model shows a superior capability in rendering the mechanical response of the brain, an extension of this model to Multimode Maxwell viscoelastic solid is proposed for modeling the tissue behavior under a more complex load-hold-unload indentation cycle that shows acceptable agreement with experimental observations.

CD Obesity-Prone Rats, but not Obesity-Resistant Rats, Robustly Ferment Resistant Starch Without Increased Weight or Fat Accretion.

OBJECTIVE: This study used CD obesity-prone (OP) and obesity-resistant (OR) rats to examine how weight gain and fat accretion relate to fermentation levels and microbiota composition after feeding resistant starch (RS). METHODS: After feeding OP rats and OR rats a high-fat (HF) diet for 4 weeks, rats were stratified into three groups: they were fed either an HF diet (group 1: HF-HF) or were switched to a low-fat (LF) diet (group 2: HF-LF) or an LF diet supplemented with 20% RS by weight for 4 weeks (group 3: HF-LFRS). Energy intake, body weight, fermentation variables, and microbiota composition were determined. RESULTS: In OP rats, RS elicited robust fermentation (increased cecal contents, short-chain fatty acids, and serum glucagon-like peptide 1). Total bacteria, species of the Bacteroidales family S24-7, and the archaean Methanobrevibacter smithii increased. The robust fermentation did not elicit higher weight or fat accretion when compared with that of control rats fed the same isocaloric diets (HF-LF ± RS). In OR rats, body weight and fat accretion were also not different between HF-LF ± RS diets, but RS elicited minimal changes in fermentation and microbiota composition. CONCLUSIONS: Robust fermentation did not contribute to greater weight. Fermentation levels and changes in microbiota composition in response to dietary RS differed by obesity phenotype.

Obese ZDF rats fermented resistant starch with effects on gut microbiota but no reduction in abdominal fat.

SCOPE: To determine if whole-grain (WG) flour with resistant starch (RS) will produce greater fermentation than isolated RS in obese Zucker Diabetic Fatty (ZDF) rats, and whether greater fermentation results in different microbiota, reduced abdominal fat, and increased insulin sensitivity. METHODS AND RESULTS: This study utilized four groups fed diets made with either isolated digestible control starch, WG control flour (6.9% RS), isolated RS-rich corn starch (25% RS), or WG corn flour (25% RS). ZDF rats fermented RS and RS-rich WG flour to greatest extent among groups. High-RS groups had increased serum glucagon-like peptide 1 (GLP-1) active. Feeding isolated RS showed greater Bacteroidetes to Firmicutes phyla among groups, and rats consuming low RS diets possessed more bacteria in Lactobacillus genus. However, no differences in abdominal fat were observed, but rats with isolated RS had greatest insulin sensitivity among groups. CONCLUSIONS: Data demonstrated ZDF rats (i) possess a microbiota that fermented RS, and (ii) WG high-RS fermented better than purified RS. However, fermentation and microbiota changes did not translate into reduced abdominal fat. The defective leptin receptor may limit ZDF rats from responding to increased GLP-1 and different microbiota for reducing abdominal fat, but did not prevent improved insulin sensitivity.