Clustering analysis of lipoprotein profiles to identify subtypes of hypertriglyceridemia in Miniature Schnauzers

BACKGROUND

Hypertriglyceridemia (HTG) is prevalent in Miniature Schnauzers, predisposing them to life-threatening diseases. Varied responses to management strategies suggest the possibility of multiple subtypes.

HYPOTHESIS/OBJECTIVE

To identify and characterize HTG subtypes in Miniature Schnauzers through cluster analysis of lipoprotein profiles. We hypothesize that multiple phenotypes of primary HTG exist in this breed.

ANIMALS

Twenty Miniature Schnauzers with normal serum triglyceride concentration (NTG), 25 with primary HTG, and 5 with secondary HTG.

METHODS

Cross-sectional study using archived samples. Lipoprotein profiles, generated using continuous lipoprotein density profiling, were clustered with hierarchical cluster analysis. Clinical data (age, sex, body condition score, and dietary fat content) was compared between clusters.

RESULTS

Six clusters were identified. Dogs with primary HTG were dispersed among 4 clusters. One cluster showed the highest intensities for triglyceride-rich lipoprotein (TRL) and low-density lipoprotein (LDL) fractions and also included 4 dogs with secondary HTG. Two clusters had moderately high TRL fraction intensities and low-to-intermediate LDL intensities. The fourth cluster had high LDL but variable TRL fraction intensities with equal numbers of NTG and mild HTG dogs. The final 2 clusters comprised only NTG dogs with low TRL intensities and low-to-intermediate LDL intensities. The clusters did not appear to be driven by differences in the clinical data.

CONCLUSIONS AND CLINICAL IMPORTANCE

The results of this study support a spectrum of lipoprotein phenotypes within Miniature Schnauzers that cannot be predicted by triglyceride concentration alone. Lipoprotein profiling might be useful to determine if subtypes have different origins, clinical consequences, and response to treatment.

Effect of Holstein genotype on ex-vivo interleukin-1β response to lipopolysaccharide (LPS), lipoteichoic acid (LTA) and heat-killed Gram-negative and Gram-positive bacteria

Effects of Holstein genotype on interleukin-1β response were assessed by ex-vivo stimulation of whole blood with lipopolysaccharide (LPS), lipoteichoic acid (LTA), or sonicated, heat-killed Gram-negative or Gram-positive bacteria. Holstein genotypes were unselected Holsteins (UH, n = 14) not subjected to selection pressures since the mid-1960s and contemporary Holsteins (CH, n = 13). Milk yield of UH and CH cows differ by more than 4500 kg/lactation. Whole blood was mixed with 0.01 µg LPS, 10 µg LTA or 2.5 × 10⁶ CFU of sonicated, heat-killed E. coli, K. pneumoniae, S. marcescens, S. aureus, S. dysgalactiae, or S. uberis per mL of blood and incubated (4 h, 37 °C). Plasma IL-1β was quantified by ELISA and log₁₀-transformed concentrations analyzed with a multivariate linear mixed effects model. Responses to bacteria were greater than responses to LPS or LTA. Responses to LPS, LTA and the Gram-negative stimulants were greater in UH than in CH cows while responses to the Gram-positive bacteria did not differ between Holstein genotypes. In both genotypes, strong correlations were detected among IL-1β responses to the Gram-negative stimulants and to LTA. There were strong correlations among IL-1β responses to the Gram-positive bacteria in CH cows but only between S. aureus and S. dysgalactiae in UH cows. The IL-1β response to S. uberis was highly correlated with responses to all of the Gram-negative stimulants in CH cows but only with E. coli in the UH cows. The reduced immune response could make contemporary cows more susceptible to infection by Gram-negative bacteria. Results confirm selection practices since the mid-1960s have altered immune response in the Holstein, at least to Gram-negative bacteria, and validate the need for additional studies to further evaluate the impacts of these selection practices on immune function in contemporary Holsteins.

Retrospective study of 20 cats surgically treated for insulinoma

OBJECTIVE

To report the clinical signs, histopathology results, and prognostic factors for outcomes following excision for feline insulinoma (INS).

STUDY DESIGN

Retrospective study.

SAMPLE POPULATION

Twenty client-owned cats.

METHODS

Medical records from 2006 to 2020 were reviewed by Veterinary Society of Surgical Oncology members for cats with hypoglycemia resulting from INS, with surgical excision and follow up. Clinical signs and histopathology results were summarized. Factors potentially related to disease-free interval (DFI), disease-related death (DRD), and overall survival time (OST) were analyzed with a Cox proportional hazards regression analysis.

RESULTS

All cats were hypoglycemic on presentation with neurologic signs in 18 out of 20 and inappropriate insulin levels in 12/13. Excision of insulinomas resulted in immediate euglycemia or hyperglycemia in 18 cats. Eighteen cats survived to hospital discharge. The median time to death or last postoperative follow up was 664 days (range: 2-1205 days). Prognostic factors included age at presentation (for DFI); time to postoperative euglycemia (for DRD); preoperative and postoperative serum blood glucose concentrations; metastasis at the time of surgery (DFI and DRD), and histopathologic tumor invasion (for OST). The median OST for all cats was 863 days. The 1-, 2- and 3-year survival rates were 75%, 51%, and 10%, respectively.

CONCLUSION

Excision of insulinoma resulted in euglycemia or hyperglycemia in most cats. Negative prognostic factors included young age, low serum glucose concentrations, metastasis at time of surgery, tumor invasion, and shorter time to euglycemia.

CLINICAL SIGNIFICANCE

Surgical excision resulted in survival times comparable to those of canine INS.

Evaluation of coated platelets, a subset of highly procoagulant platelets, in healthy dogs and dogs with neoplasia

OBJECTIVE

To determine if dogs with neoplasia produce more coated platelets, a subpopulation of activated platelets generated by dual stimulation with thrombin and convulxin, a glycoprotein VI agonist, than healthy control dogs.

ANIMALS

Client-owned dogs diagnosed with lymphoma (n = 19) or solid tumors (14) and healthy control dogs (14).

PROCEDURES

Platelets were stimulated ex vivo with thrombin and convulxin. Flow cytometry was used to quantify the percentage of coated platelets based on high levels of surface fibrinogen. To compare the percentage of coated platelets between the three groups, an ANOVA was performed followed by pairwise 95% confidence intervals (CI) adjusted for multiple comparisons using Tukey's method.

RESULTS

We observed a greater mean percentage of coated platelets in dogs with solid tumors, compared with healthy control dogs, by 10.9 percentage points (95% CI: -1.0, 22.8), and a mean percentage of coated platelets in dogs with lymphoma that was less than healthy control dogs by 0.3 percentage points (95% CI: -11.4, 10.8).

CLINICAL RELEVANCE

This study provides the first data-based evidence that dogs with solid tumors may have a greater mean coated platelet percentage when compared with healthy control dogs, although there is overlap between groups. Further studies are needed investigating coated platelets in specific subsets of neoplasia and investigating additional mechanisms of hypercoagulability in dogs with neoplasia.

Validation of the 0-10 verbal numeric scale for assessment of pruritus severity in dogs

BACKGROUND

The pruritus Visual Analog Scale (pVAS) is currently the only validated tool for assessing canine pruritus. A verbal numeric scale (VNS) offers an alternative if clients are not present or able to complete the pVAS.

HYPOTHESIS/OBJECTIVE

To validate the 0-10 VNS and evaluate its interchangeability with the pVAS.

ANIMALS

251 dogs were included in the study.

MATERIALS AND METHODS

Dog owners were asked to assess their pet's pruritus level using the pVAS, the 0-10 VNS and the verbal rating categories (mild, moderate, severe) in one or two subsequent visits. To be valid, VNS must satisfy the following: correlate with pVAS (criterion validity); indicate reduction in itch score after an antipruritic intervention (construct validity); and have scores related to the verbal rating categories that are significantly different (content validity). VNS and pVAS interchangeability and the percentage of clients that preferred the VNS and pVAS also were evaluated.

RESULTS

The VNS and pVAS correlation for visits 1 and 2 was good (r_ICC  = 0.9) and excellent (r_ICC  = 0.94). The VNS scores were significantly decreased after antipruritic interventions (P < 0.001). The VNS scores associated with the verbal rating scale categories (mild, moderate and severe) were significantly different (P < 0.001). The 95% limits of agreement for the pVAS and VAS were outside the limit of acceptability of ±2 (-2.0, 2.57). Most clients (69%) preferred the pVAS to the VNS.

CONCLUSIONS AND CLINICAL RELEVANCE

The VNS is a valid scale to evaluate canine pruritus; however, the VNS and pVAS are not interchangeable.

CAR/CXCR5-T cell immunotherapy is safe and potentially efficacious in promoting sustained remission of SIV infection

During chronic human immunodeficiency virus (HIV) or simian immunodeficiency virus (SIV) infection prior to AIDS progression, the vast majority of viral replication is concentrated within B cell follicles of secondary lymphoid tissues. We investigated whether infusion of T cells expressing an SIV-specific chimeric antigen receptor (CAR) and the follicular homing receptor, CXCR5, could successfully kill viral-RNA+ cells in targeted lymphoid follicles in SIV-infected rhesus macaques. In this study, CD4 and CD8 T cells from rhesus macaques were genetically modified to express antiviral CAR and CXCR5 moieties (generating CAR/CXCR5-T cells) and autologously infused into a chronically infected animal. At 2 days post-treatment, the CAR/CXCR5-T cells were located primarily in spleen and lymph nodes both inside and outside of lymphoid follicles. Few CAR/CXCR5-T cells were detected in the ileum, rectum, and lung, and no cells were detected in the bone marrow, liver, or brain. Within follicles, CAR/CXCR5-T cells were found in direct contact with SIV-viral RNA+ cells. We next infused CAR/CXCR5-T cells into ART-suppressed SIV-infected rhesus macaques, in which the animals were released from ART at the time of infusion. These CAR/CXCR5-T cells replicated in vivo within both the extrafollicular and follicular regions of lymph nodes and accumulated within lymphoid follicles. CAR/CXR5-T cell concentrations in follicles peaked during the first week post-infusion but declined to undetectable levels after 2 to 4 weeks. Overall, CAR/CXCR5-T cell-treated animals maintained lower viral loads and follicular viral RNA levels than untreated control animals, and no outstanding adverse reactions were noted. These findings indicate that CAR/CXCR5-T cell treatment is safe and holds promise as a future treatment for the durable remission of HIV.

Behavioral and Physiologic Effects of Dirty Bedding Exposure in Female ICR Mice

Exposure of sentinel mice to dirty bedding is commonly used in health monitoring programs to screen colonies for clinical and subclinical disease. Despite the potential stressors present in dirty bedding, including but not limited to microorganisms, pheromones, and ammonia, it is unknown whether sentinel mice exposed to soiled bedding experience stress. In this study, select behavioral and physiologic changes associated with stress were assessed in female ICR mice exposed to dirty bedding. Behavioral parameters included evaluation in the home cage and selected behavioral tests; physiologic measurements included neutrophil:lymphocyte ratio and weight. Mice in the acute group were exposed for 24 h whereas mice in the chronic group were exposed for 4 wk. Mice in the chronic group exposed to dirty bedding weighed less at days 21 and 28 than did control mice. Chronic mice exposed to dirty bedding also exhibited decreased net weight gain over the entire study period as compared with control mice. No significant differences were detected in the other behavioral and physiologic parameters measured. These results indicate that dirty bedding exposure may affect sentinel mice, but further investigation is needed to determine the specific mechanism(s) behind the weight difference.

Relationship of tissue dimensions and three captive bolt placements on cadaver heads from mature swine (Sus scrofa domesticus) > 200 kg body weight

Three penetrating captive bolt (PCB) placements were tested on cadaver heads from swine with estimated body weight (BW) >200 kg (sows = 232.9 ± 4.1 kg; boars = 229.3 ± 2.6 kg). The objectives were to determine tissue depth, cross-sectional brain area, visible brain damage (BD), regions of BD, and bolt-brain contact; and determine relationships between external head dimensions and tissue depth at each placement. A Jarvis PAS - Type P 0.25R PCB with a Long Stunning Rod Nosepiece Assembly and 3.5 gr power loads was used at the following placements on heads from 111 sows and 46 boars after storage at 2-4° C for approximately 62 h before treatment: FRONTAL (F) - 3.5 cm superior to the optic orbits at midline, TEMPORAL (T) - at the depression posterior to the lateral canthus of the eye within the plane between the lateral canthus and the base of the ear, or BEHIND EAR (BE) - directly caudal to the pinna of the ear on the same plane as the eyes and targeting the middle of the opposite eye. For sows, the bolt path was in the plane of the brain for 42/42 (100%, 95% CI: 91.6-100.0%) F heads, 39/40 (97.5%, 95% CI: 86.8-99.9%) T heads, and 34/39 (87.5%, 95% CI: 72.6-95.7%) BE heads; for the heads that could reliably be assessed for BD damage was detected in 25/26 (96.2%, 95% CI: 80.4-99.9%) F heads, 24/35 (68.6%, 95% CI: 50.7-83.2%) T heads, and 5/40 (12.5%, 95% CI: 4.2-26.8%) BE heads. For boars, the bolt path was in the plane of the brain for 17/17 (100.0%, 95% CI: 80.5-100.0%) F heads, 18/18 (100.0%, 95% CI: 81.5-100.0%) T heads, and 14/14 (100.0%, 95% CI: 76.8-100.0%) BE heads; damage was detected in 11/12 (91.7%, 95% CI: 61.5-99.8%) F heads, 2/15 (13.3%, 95% CI: 1.7-40.5%) T heads, and 7/14 (50.0%, 95% CI: 23.0-77.0%) BE heads. Tissue depth was reported as mean ± standard error followed by 95% one-sided upper reference limit (URL). For sows, total tissue thickness was different (P < 0.05) between placements (F: 52.7 ± 1.0 mm, URL: 64.1 mm; T: 69.8 ± 1.4 mm, URL: 83.9 mm; BE: 89.3 ± 1.5 mm, URL: 103.4 mm). In boars, total tissue thickness was different (P < 0.05) between placements (F: 41.2 ± 2.1 mm, URL: 56.3 mm; T: 73.2 ± 1.5 mm, URL: 83.4 mm; BE: 90.9 ± 3.5 mm, URL: 113.5 mm). For swine > 200 kg BW, F placement may be more effective than T or BE due to less soft tissue thickness, which may reduce concussive force. The brain was within the plane of bolt travel for 100% of F heads with brain damage for 96.2% and 91.7% of F sow and boar heads, respectively.

Retrospective evaluation of fluid production at the time of thoracostomy tube removal following elective and emergency surgery in dogs (2010-2017): 185 cases

OBJECTIVE

To report the rate of fluid production at the time of removal of thoracostomy tubes placed intraoperatively and to determine the association of this rate with specific patient factors, surgical factors, or clinical diagnosis. The secondary objective was to determine whether identification of pleural effusion within 2 weeks of thoracostomy tube removal was associated with the same variables.

DESIGN

Retrospective study.

SETTING

University teaching hospital.

ANIMALS

One hundred eighty-five client-owned dogs with thoracostomy tubes placed intraoperatively between January 2010 and March 2017.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Thoracostomy tubes were removed at a median fluid production of 0.09 mL/kg/h (range, 0-7.0 m L/kg/h). Median fluid production at the time of thoracostomy tube removal was significantly higher in dogs with preoperative pleural effusion compared to dogs without preoperative pleural effusion (0.21 vs 0.05 mL/kg/h; P = 0.0001) and in dogs that had a median sternotomy compared to dogs that had a lateral thoracotomy (0.14 vs 0.09 mL/kg/h; P = 0.04). Of the 169 dogs available for follow-up, 12 (7.1%) had pleural effusion within 2 weeks of removal of the thoracostomy tube. Detection of pleural effusion during the follow-up period was significantly associated with the presence of preoperative pleural effusion (P = 0.0019) and the diagnosis (P = 0.01). A greater proportion of dogs with a lung lobe torsion (4/9, 44.4%) and idiopathic chylothorax (2/7, 28.5%) had pleural effusion within 2 weeks compared to other diagnoses. Reintervention was performed in 4.7% of dogs.

CONCLUSIONS

Thoracostomy tubes were removed at pleural fluid production rates that frequently exceeded current veterinary guidelines. However, the fluid production rate at the time of thoracostomy tube removal was not associated with the detection of pleural effusion within 2 weeks of thoracostomy tube removal, and the overall need for reintervention following thoracostomy tube removal was low (4.7%).

Public Views of Dairy Calf Welfare and Dairy Consumption Habits of American Youth and Adults

The primary objective of this study was to explore views of dairy calf welfare and dairy product consumption habits among youth and adults. The secondary objective was to explore views of dairy calf welfare and dairy product consumption habits among a subset of parent-child pairs. Participants 5–17 years of age (n = 463) and 18 years old or greater (n = 1,310) completed an in-person survey at the Minnesota State Fair (St. Paul, MN, USA) in summer 2018. A subset of these data was comprised of parent-child pairs (n = 188). The survey was administered via Qualtrics using iPads and included multiple-choice questions about demographics and calf welfare, an open-ended question on “what dairy calves need to have a good life,” and multiple-choice questions about participants' consumption of dairy products and nondairy alternative products. Content analysis was used for responses to the open-ended question, and concepts to describe dairy calf welfare views were identified. Fisher's exact test and Cohen's Kappa were used to investigate the relationships between parent-child pair responses about dairy calf welfare. In addition to these methods, prevalence-adjusted and bias-adjusted kappa (PABAK) were used to investigate the relationships between parent-child pair responses about consumption habits. The median age of all youth participants was 11 years and 61% were female, 82% were urban residents, and 63% did not have prior experience handling agricultural animals but 83% had visited a farm in the past. Most youth participants (94.4%) indicated that they consumed dairy products, while 47.1% consumed nondairy alternatives products. Median age range of all adult participants was 45–54 years, 65% were female, 82% urban residents, and 81% did not have prior experience handling agricultural animals but 63% had visited a farm in the past. Most adult participants (94%) indicated that they consumed dairy products and 47% indicated that they consumed nondairy alternative products. In response to “what dairy calves need to have a good life,” youth and adults most commonly focused on issues related to biological functioning (82 and 70% of youth and adults mentioning this concept, respectively), followed by natural living (44 and 50%, respectively), humane care (30 and 20%, respectively), and affective states (5% of both youth and adults). For the natural living concept of animal welfare, parent and child responses were slightly associated (Kappa = 0.19; P = 0.01; overall agreement = 61%). Almost all participants reported consuming dairy products, therefore, the agreement is high between parents and children because in most households (90%), both parents and children consume dairy products. However, child consumption was observed to be lower (75%, 9/12) when parents do not consume dairy than when parents do consume dairy (95%, 167/176), leading to a Kappa of 0.20 (P = 0.006, PABAK = 0.81) and a slight association between parents and children. The results suggest that biological functioning is highly valued by the public and views of parents and their children related to natural living in dairy calves are slightly associated.

Retrospective evaluation of thrombocytopenia and tumor stage as prognostic indicators in dogs with splenic hemangiosarcoma

OBJECTIVE

To identify physical examination and perioperative CBC variables in dogs with splenic hemangiosarcoma (HSA) that could aid in predicting progression-free interval (PFI) and overall survival time (OST) in affected dogs.

ANIMALS

70 client-owned dogs with splenic HSA treated with splenectomy and chemotherapy between September 2004 and October 2016.

PROCEDURES

A retrospective search of the University of Minnesota Veterinary Medical Center medical records database was performed to identify dogs with splenic HSA treated with splenectomy and with evidence in the medical records of intent to treat with chemotherapy. Data collection included dog signalment and body surface area, results from CBCs performed within 6 days before to 2 days after splenectomy, whether dogs had hemoabdomen or received transfusions, and tumor stage. Hematocrit, WBC count, and platelet count were treated as categorical variables (divided into terciles: above, within, or below reference limits) because of variation among reference intervals for the numerous analyzers used. Associations between variables and PFI or OST were investigated with Cox regression analyses, and hazard ratios (HRs) for a shorter PFI or OST were reported. Population Pearson correlation coefficient (ρ) analysis was performed to identify potential associations between variables of interest.

RESULTS

Stage 3 HSA was identified as a negative prognostic indicator of PFI (HR, 6.6) and OST (HR, 4.5). Perioperative thrombocytopenia was similarly associated with shorter PFI (HR, 2.2) and OST (HR, 2.0). Results for Hct correlated (ρ = 0.58) with those for platelet count, and although our findings did not indicate a notable association between anemia and shorter PFI, such could not be ruled out.

CONCLUSIONS AND CLINICAL RELEVANCE

The prognostic value of thrombocytopenia warrants further substantiation to understand causal and mechanistic connections, and the presence of thrombocytopenia ultimately may prove valuable in guiding treatment recommendations for dogs with splenic HSA.

Optimization of histologic grading schemes in spontaneous and surgically-induced murine models of osteoarthritis

OBJECTIVE

To compare the Osteoarthritis Research Society International (OARSI) and Articular Cartilage Structure (ACS) grading schemes applied to multiple and single sections, along with additional histologic measures, in two mouse models of Osteoarthritis (OA).

METHODS

Six coronal histologic stifle joint sections were collected from 40 C57BL/6J mice, including aged mice with spontaneous OA (approximately 18 months of age; n = 15) and young (12-week-old) mice that either underwent destabilization of the medial meniscus (DMM) surgery (n = 15) or sham surgery (n = 10). Sections were evaluated with the standard OARSI (0-6) scheme, a modified OARSI scheme, the ACS (0-12) scheme, histomorphometry of cartilage and bone, and scoring of osteophytes (0-3) and synovial hyperplasia (0-3). Principal components analysis (PCA) was used to determine the features explaining the greatest variability among the sections.

RESULTS

The grading schemes performed similarly when applied to a single mid-coronal section or six total coronal sections per joint. OARSI grading produced similar results when applied to hematoxylin and eosin or toluidine blue-stained sections. Aged mice had higher severity scores in the LTP than DMM mice (mid-coronal OARSI grade aged = 2.3 and DMM = 1.1, p = 0.0006; ACS grade aged = 4.1 and DMM = 1.6, p = 0.0024). PCA resulted in retention of four factors that accounted for 78.4% of the total variance. Factor 1 (36.4%) included the OARSI grade, ACS grade, Toluidine blue grade, articular cartilage area and thickness and the osteophyte grade.

CONCLUSIONS

Grading of a single mid-coronal section using either the OARSI or ACS schemes combined with osteophyte and histomorphometric measures can consistently define OA severity in mice.

Retrospective analysis of the effects of Blastomyces antigen concentration in urine and radiographic findings on survival in dogs with blastomycosis

Background

The Blastomyces antigen concentration in urine (BACU) test is used to diagnose blastomycosis and monitor treatment in dogs. It is unknown if a higher BACU is associated with shorter survival.

Objectives

To determine if the magnitude of BACU before treatment is associated with survival in dogs with blastomycosis.

Animals

Fifty‐two dogs with blastomycosis.

Methods

Retrospective case review. BACU, radiographic lung severity (RLS) score (0‐4 scale), and survival time up to 1 year after diagnosis were obtained through medical record review of dogs with Blastomyces dermatitidis.

Results

The overall survival was: discharge, 87%; 1 week, 85%; 2 months, 74%; and 6 months, 69%. BACU correlated with RLS score (r_s = 0.33, P = .02). BACU and RLS scores were lower in survivors to 2 months than nonsurvivors (average BACU difference of 2.5 ng/mL, 95% confidence interval [CI]: 0.2‐4.8 ng/mL, P = .04; median RLS difference of 2; range, 0‐4, P = .02). Dogs with BACU <5 ng/mL and dogs with mild (0‐1) RLS scores had a greater proportion surviving than those with BACU >5 ng/mL (P = .03) and dogs with severe (3‐4) RLS scores (P = .04). All dogs with a BACU <5 ng/mL or mild RLS score were alive at last follow‐up (median, 365 days; range, 44‐365 days). In all, 68.1% of other dogs survived to 2 months (95% CI, 54.8%‐84.8%).

Conclusions and Clinical Importance

Dogs with lower BACU and RLS scores have improved survival; however, it is unclear what specific cutoffs should be used for prognosis.

Indicators of Postoperative Pain in Syrian Hamsters (Mesocricetus auratus)

Despite the use of Syrian hamsters (Mesocricetus auratus) in research, little is known about the evaluation of pain in this species. This study investigated whether the frequency of certain behaviors, a grimace scale, the treat-take-test proxy indicator, body weight, water consumption, and coat appearance could be monitored as signs of postoperative pain in hamsters in a research setting. Animals underwent no manipulation, anesthesia only or laparotomy under anesthesia. An ethogram was constructed and used to determine the frequencies of pain, active and passive behaviors by in-person and remote videorecording observation methods. The Syrian Hamster Grimace Scale (SHGS) was developed for evaluation of facial expressions before and after the surgery. The treat-take-test assessed whether surgery would affect the animals' motivation to take a high-value food item from a handler. The hypothesis was that behavior frequency, grimace scale, treat-take-test score, body weight, water consumption, and coat appearance would change from baseline in the surgery group but not in the no-intervention and anesthesia-only groups. At several time points, pain and passive behaviors were higher than during baseline in the surgery group but not the anesthesia-only and no-intervention groups. The SHGS score increased from baseline scores in 3 of the 9 animals studied after surgery. The frequency of pain behaviors and SHGS scores were highly specific but poorly sensitive tools to identify animals with pain. Behaviors in the pain category were exhibited by chiefly, but not solely, animals that underwent the laparotomy. Also, many animals that underwent laparotomy did not show behaviors in the pain category. Treat-take-test scores, body weight, water consumption, and coat appearance did not change from baseline in any of the 3 groups. Overall, the methods we tested for identifying Syrian hamsters experiencing postoperative pain were not effective. More research is needed regarding clinically relevant strategies to assess pain in Syrian hamsters.

The effect of individual versus pair housing of dairy heifer calves during the preweaning period on measures of health, performance, and behavior up to 16 weeks of age

Pair housing of dairy heifer calves during the preweaning period helps meet the natural social needs of the calf and has been shown to improve growth and starter intake during the preweaning period as compared with individual housing. However, there is little evidence to suggest that pair-housed calves maintain their social and growth advantages past the weaning phase. The objective of this study was to investigate the effect of pair housing on measures of calf performance, health, and behavior up to 16 wk of age. Healthy Holstein and crossbred heifer calves were enrolled in the study after colostrum feeding, with the first calf randomly assigned to 1 of 2 housing treatments: pair (PR; 2 hutches with common outdoor space) or individual (INDV; 1 hutch plus outdoor space). All calves were bucket fed 4 L of milk replacer twice daily and weaned at 50 d of age. Weaned calves (6/group) remained with their treatment group until exit from the study at 16 wk. A venous blood sample was collected from each calf between 24 h and 7 d of age to test for serum total protein (g/dL). Body weights (kg) were obtained at birth, weaning, and 16 wk. Each enrolled calf was scored for health each week and calf health treatments were also collected. A hair sample was collected from the left shoulder at birth and 16 wk to assess hair cortisol (pg/mL). At enrollment, each calf was fitted with a triaxial accelerometer on the left hind leg for continuous recording of standing and lying time (min/24 h) for 16 wk. Latency to find feed, water, and lie down (min) at entrance to the weaned pen were recorded by continuous video observation. Open field testing with a novel object was performed at 5, 10, and 16 wk. Behaviors analyzed by video observation included latency to approach the object (s), vocalizations (n), and time spent immobile, walking, or running (s/10 min). Linear mixed models were used to determine the effect of treatment (INDV or PR) on calf growth, activity, and behavioral outcomes, which accounted for time, breed, the interaction of time and treatment, the random pen, and variability in testing day and repeated measurements within calf when appropriate. Twenty-four Holstein and crossbred calves (PR: n = 12, 6 pairs; INDV: n = 12) were enrolled from November 2 to December 23, 2018. The PR calves were 7.1 kg heavier at weaning and gained 0.15 kg/d more during the preweaning period as compared with INDV calves. In the 24 h after movement to the postweaning pen, PR calves lay down for longer periods of time (14.3 vs. 11.0 ± 0.4 h/d), and PR calves urinated more during novel object testing at 5 wk of age. Our study demonstrated benefits, such as better growth and increased lying time, of pair housing calves during the preweaning period.

Comparison of Semi-Cylindrical Recession Trochleoplasty and Trochlear Block Recession for the Treatment of Canine Medial Patellar Luxation: A Pilot Study

OBJECTIVE

 The aim of this study was to describe an alternative method for trochleoplasty, semi-cylindrical recession trochleoplasty (SCRT), and compare it to trochlear block recession (TBR) in regard to recessed trochlear depth, patellar depth, patellar articular contact with the trochlea, recessed trochlear surface area, procedure time, complications and functional outcome.

STUDY DESIGN

 Ten dogs with bilateral grade II-III medial patellar luxations underwent bilateral simultaneous correction surgery including tibial tuberosity transposition, lateral imbrication and trochleoplasty with one stifle each undergoing TBR and SCRT. Patients received pre-and postoperative stifle computed tomography scans and pre- and 8-week postoperative pressure platform analysis and physical examinations. Recessed trochlear depth, patellar depth, trochlear surface area, patellar articular contact, procedure time, complications and functional outcomes as measured by gait analysis were compared between the two techniques.

RESULTS

 There was no significant difference in measured outcome variables between techniques at any time point. At the time of the 8-week reassessment, no patella had reluxated.

CONCLUSION

 Short-term follow-up shows similar functional outcomes between both techniques regarding rate of reluxation and limb function. The SCRT was subjectively easier to perform than TBR, particularly in small patients. The SCRT is an acceptable method of trochleoplasty for the treatment of medial patellar luxation in dogs and further studies evaluating long-term outcomes are justified.

Assessment of the FAM174A 11G allele as a risk allele for equine metabolic syndrome

An 11G nucleotide repeat in the 3' UTR of FAM174A was recently postulated as a risk allele with a dominant mode of inheritance for equine metabolic syndrome (EMS) and laminitis status in Arabian horses. The objective of this project was to evaluate this hypothesis in a large and diverse across-breed population. A total of 301 ponies, 292 Morgans, 64 Arabians, 49 Tennessee Walking Horses and 59 Quarter Horses were genotyped for six observed G repeat alleles in the FAM174A 3' UTR. Phenotype data included laminitis status, baseline insulin, glucose, non-esterified fatty acids, triglycerides, adiponectin, leptin, ACTH, insulin and glucose post oral sugar test, and two proxies for insulin resistance. The 11G allele frequencies were 18.8, 6.9, 1.8, 0.2 and 0.0% in the Arabians, Tennessee Walkers, ponies, Morgans and Quarter Horses respectively. Association analyses between FAM174A genotype and EMS phenotypes, and between allele count and EMS phenotypes, identified no statistically significant associations. When a dominant effect for the 11G allele was evaluated, a statistically significant association with adiponectin levels was identified in the ponies, and pairwise comparisons revealed that the estimated marginal means were higher in ponies with the 11G allele vs. alternative alleles (i.e. the allele had a protective effect). In conclusion, our data do not support the FAM174A 11G allele as a risk allele for EMS in our studied breeds.

Rapid Transduction and Expansion of Transduced T Cells with Maintenance of Central Memory Populations

Chimeric antigen receptor (CAR)-T cells show great promise in treating cancers and viral infections. However, most protocols developed to expand T cells require relatively long periods of time in culture, potentially leading to progression toward populations of terminally differentiated effector memory cells. Here, we describe in detail a 9-day protocol for CAR gene transduction and expansion of primary rhesus macaque peripheral blood mononuclear cells (PBMCs). Cells produced and expanded with this method show high levels of viability, high levels of co-expression of two transduced genes, retention of the central memory phenotype, and sufficient quantity for immunotherapeutic infusion of 1-2 × 108 cells/kg in a 10 kg rhesus macaque. This 9-day protocol may be broadly used for CAR-T cell and other T cell immunotherapy approaches to decrease culture time and increase maintenance of central memory populations.

Comparison of immediate versus delayed streak plate inoculation on urine bacterial culture and susceptibility testing in dogs and cats

BACKGROUND

Quantitative bacterial culture and susceptibility testing is the gold standard diagnostic for determining bacterial urinary tract infection. Transport of samples to external reference laboratories is common practice in veterinary medicine.

OBJECTIVE

To compare bacterial culture and susceptibility results from clinical urine samples when streak plate inoculation is performed immediately after sample collection versus after transport to a reference laboratory. To determine the clinical implications of discrepant culture results.

ANIMALS

One hundred and ninety-four canine and 45 feline urine samples that were submitted for urinalysis and urine culture and susceptibility testing.

METHODS

This was a prospective, cross-sectional study. Streak plate inoculations were performed on urine samples immediately after collection and also after transport to a reference laboratory. Samples were stored in plain sterile tubes and refrigerated up to 24 hours before transport. Culture results were compared, and discordant results were evaluated for clinical relevance. Signalment, comorbidities, lower urinary tract signs, and antimicrobial history were recorded.

RESULTS

Kappa coefficient for agreement between plating methods was 0.884. Twenty-two (71%) of 31 discrepant results were determined to have no clinical impact. Though 35% of clean midstream samples had discrepant culture results, only 8% of these had clinical impact. Conversely, 8.6% from cystocentesis were discrepant, but 41% of these had clinical impact.

CONCLUSIONS AND CLINICAL IMPORTANCE

Provided urine samples are stored and transported appropriately, the immediate preplating of urine for culture and susceptibility testing is unnecessary in the majority of cases. Despite more discrepancies in plating methods for midstream samples, the minority were of clinical importance.

Determination of a serum total calcium concentration threshold for accurate prediction of ionized hypercalcemia in dogs with and without hyperphosphatemia

Background

Total serum calcium (tCa) concentrations are poorly predictive of ionized calcium (iCa) status in dogs.

Hypothesis

There is an optimal threshold of tCa concentration that is highly predictive of ionized hypercalcemia and this threshold is higher in hyperphosphatemic dogs as compared to nonhyperphosphatemic dogs.

Animals

Nonhyperphosphatemic (n = 1593) and hyperphosphatemic (n = 250) adult dogs.

Methods

Retrospective medical record review of paired tCa and iCa concentration measurements in dogs presented to a university teaching hospital over a 5‐year period. Positive and negative predictive values, sensitivity, and specificity were calculated for tCa concentration thresholds of 11.0‐15.0 mg/dL (upper limit of laboratory reference interval = 11.5 mg/dL) in nonhyperphosphatemic and hyperphosphatemic groups.

Results

In nonhyperphosphatemic dogs, an optimal tCa concentration threshold of 12.0 mg/dL resulted in a positive predictive value of 93% (95% confidence interval [CI], 84%‐98%) and sensitivity of 52% (95% CI, 43%‐61%) for ionized hypercalcemia. An optimal tCa concentration threshold was not identified for hyperphosphatemic dogs. The nonhyperphosphatemic dogs had a higher prevalence of ionized hypercalcemia than the hyperphosphatemic dogs (7 versus 3%, P = .04) and a lower prevalence of ionized hypocalcemia (23 versus 62%, respectively; P < .001).

Conclusions and Clinical Importance

High tCa concentrations are strongly predictive of ionized hypercalcemia in nonhyperphosphatemic adult dogs and should prompt further diagnostic testing to determine the underlying cause of hypercalcemia. In this population, dogs without increased tCa concentrations rarely had ionized hypercalcemia, but iCa concentrations still should be evaluated in patients with tCa concentrations within the reference interval if there is clinical suspicion for calcium abnormalities.

An in-home intervention of parent-implemented strategies to increase child vegetable intake: results from a non-randomized cluster-allocated community trial

Background

Less than 2% of children in the U.S., ages 9–13, meet the minimum dietary recommendations for vegetable intake. The home setting provides potential opportunities to promote dietary behavior change among children, yet limited trials exist with child vegetable intake as a primary outcome. Strategies to increase vegetable intake grounded in behavioral economics are no/low cost and may be easily implemented in the home by parents.

Methods

This non-randomized, controlled study tested whether an intervention of parent-led strategies informed by behavioral economics and implemented within a series of 6 weekly parent-child vegetable cooking skills classes, improved dietary outcomes of a diverse sample of low-income children (ages 9–12) more than the vegetable cooking skills classes alone. The primary outcomes were total vegetable intake, dietary quality (HEI scores), total energy intake, vegetable liking, variety of vegetables tried, child BMI-z score, and home availability of vegetables. Outcome measures were collected at baseline, immediate post-treatment, 6 and 12 months follow-up. Mixed model regression analyses with fixed independent effects (treatment condition, time point and treatment condition x time interaction) were used to compare outcomes between treatment conditions.

Results

A total of 103 parent/child pairs (intervention = 49, control = 54) were enrolled and 91 (intervention = 44, control = 47) completed the weekly cooking skills program. The intervention did not improve child total vegetable intake. Intervention children increased dark green vegetable intake from immediate post-treatment to 12 months. The number of vegetables children tried increased and mean vegetable liking decreased over time for both control and intervention children.

Conclusions

Findings from this study suggest that the strategies and the manner in which they were implemented may not be effective in low-income populations. The burden of implementing a number of strategies with potentially higher food costs may have constrained the ability of families in the current study to use the strategies as intended.

Trial registration

This trial has been retrospectively registered at : #NCT03641521 on August 21, 2018.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7079-4) contains supplementary material, which is available to authorized users.

Cytology and the cell block method in diagnostic characterization of canine lymphadenopathy and in the immunophenotyping of nodal lymphoma

Minimally invasive techniques used to evaluate canine peripheral lymphadenopathy (PLN), including fine needle aspiration biopsy with cytological evaluation (FNAB-C) and flow cytometry (FC), have benefits and limitations. The cell block (CB) method is an alternate processing technique in which fine needle aspirate biopsy samples are concentrated, fixed, and embedded in paraffin for routine histological processing/staining. Utilizing three observers, we determined the diagnostic value of the CB in evaluating canine PLN across six categories (non-diagnostic, reactive, inflammatory/infectious, probable lymphoma and lymphoma, metastatic neoplasia) and correlated findings to immunophenotypic and clonal antigen receptor rearrangement results in canine nodal lymphoma. Eighty-five paired FNAB-C and CB samples were evaluated from canine patients presenting to the University of Minnesota Veterinary Oncology or Internal Medicine services. Diagnostic quality samples were obtained in 55/85 (65%) CB and 81/85 (95%) FNAB-C samples, respectively, and nodal pathology impacted CB diagnostic yield. Overall percent agreement between diagnostic-quality FNAB-C and CB samples was 86%, but increased to 95% if the categories of lymphoma and probable lymphoma were combined. There was 100% agreement for both the diagnoses of metastatic neoplasia and reactive lymph nodes and 92% agreement for the diagnosis of lymphoma/probable lymphoma. Using immunohistochemistry (IHC), CB samples correctly immunophenotyped 22/23 (96%) cases of B-cell lymphoma, but only 1/6 (17%) cases of T-cell lymphoma. IHC was not completed on nine cases of lymphoproliferative disease because of insufficient cellularity. When the CB method (CBM) yielded diagnostic quality samples there was good to excellent agreement with FNAB-C samples and CB samples were suitable for some IHC tests.

Canine Pruritus Visual Analog Scale: how does it capture owners' perception of their pet's itching level?

BACKGROUND

Accurate measurement of pruritus severity is difficult in veterinary medicine.

OBJECTIVES

To determine how the changes in Pruritus Visual Analog Scale (PVAS) scores at follow-up visits agree with the owners' perceptions of improvement of their pet's pruritus.

ANIMALS

One hundred and ninety two pruritic dogs were included in the prospective study and 196 in the retrospective study.

METHODS AND MATERIALS

Owners were randomly assigned into five groups and PVAS scores were recorded during two consecutive visits. Group A: previous scores were shown before completing the PVAS; Group B: PVAS was completed then owners were shown previous scores and asked to repeat the PVAS; Group C: PVAS was completed as reported previously; Group D: PVAS and a 0-10 verbal scale (VS) were completed. Retrospectively, PVAS scores were analysed during at least three consecutive visits. The average percentage and kappa agreements were calculated for all groups. In addition, PVAS and VS scores were compared in Group D.

RESULTS

The average percentage and kappa agreements were higher in groups A (96%; 0.81), B [before (80%; 0.54), after (82%; 0.59) previous score] and D (85%; 0.47). Group C (79%; 0.37) had the lowest agreement. PVAS and VS scores were not significantly different (P = 0.56) in Group D. The average percentage and kappa agreements for the retrospective study were 50.8% and 0.25. The highest values (63%; 0.355) were noted at 30-60 day visit intervals.

CONCLUSIONS AND CLINICAL IMPORTANCE

Showing owners previous scores could improve how PVAS captures the owner's perception of their dog's itching level.

DLA class II haplotypes show sex-specific associations with primary hypoadrenocorticism in Standard Poodle dogs

Addison's disease (AD) is a life-threatening endocrine disorder that occurs spontaneously in both humans and dogs. Associations between MHC class II genes and AD have been shown in several human studies. Our goal was to identify MHC class II associations with AD in a large population of Standard Poodles, a breed highly predisposed to AD. We sequenced exon 2 of the class II genes DLA-DRB1, DLA-DQA1, and DLA-DQB1 in 110 affected and 101 unaffected Standard Poodles and tested for association with AD. After correcting for population structure, two haplotypes were found to confer risk of developing AD in a sex-specific manner: DLA-DRB1*015:01-DQA1*006:01-DQB1*023:01 in males (x²p = 0.03, OR 2.1) and DLA-DRB1*009:01-DQA1*001:01-DQB1*008:01:1 in females (x²p = 0.02, OR 8.43). Sex-specific associations have been previously described in human populations, but this is the first report of this kind in dogs. Consistent with findings in other studies, we found the DLA-DQA1*006:01 allele (x²p = 0.04) to be associated with AD in males independent of haplotype. In females, the haplotype DLA-DRB1*009:01-DQA1*001:01-DQB1*008:01:1 confers a very high risk for developing AD, although its frequency was rare (9 of 124 females) in our study population. Further studies are warranted to validate the findings of this exploratory dataset and to assess the usefulness of this haplotype as a risk marker for AD in female Standard Poodles. Our results highlight the importance of evaluating MHC class II disease associations in large populations, and accounting for both biological sex and population structure.

Preliminary Evaluation of Sustained-release Compared with Conventional Formulations of Meloxicam in Sheep (Ovis aries)

Sustained-release (SR) drugs refine current analgesic regimens by alleviating the need for multiple sessions of handling and restraint and by reducing the local tissue irritation that can occur due to repeated injections. Although a variety of SR drugs are already used in lab animal medicine, no studies exist that evaluate the suitability of an SR NSAID in sheep. This study used HPLC-MS to measure the plasma concentrations of 2 formulations of meloxicam-conventional and SRM- after subcutaneous administration in 6 adult ewes. Blood was collected at 0, 4, 12, 24, 36, 48, 60, 72, 84, 96, 120, 144, and 168 h after injection. In addition, physical exams, urinalysis, and biochemical analysis were performed at 0, 24, 48, and 120 h after dosage. Peak plasma concentrations were 1057 ± 433 ng/mL at 4 ± 0 h for conventional meloxicam and 3238 ± 1480 ng/mL at 6.7 ± 4.1 h for SR meloxicam (SRM). Elimination half-lives were 12.1 4.2 for CM and 15.2 ± 2.4 h for SRM. One sheep had an episode of acute renal azotemia starting 24 h after SRM administration; the episode resolved over time, and the definitive relationship to SRM administration was not determined. Plasma levels of SRM were higher than CM throughout the initial 24 h, remained variably elevated until 60 h after injection, but failed to sustain presumed therapeutic levels of 400 ng/mL for the full 72 h across all animals in this study. Further investigation is warranted to determine the safety and clinical efficacy of SRM in sheep. Currently, when SRM is used in sheep, we recommend the combination of a preemptive and multimodal analgesia regimen with clinical assessments throughout the postoperative period.

Low levels of SIV-specific CD8+ T cells in germinal centers characterizes acute SIV infection

CD8+ T cells play an important role in controlling of HIV and SIV infections. However, these cells are largely excluded from B cell follicles where HIV and SIV producing cells concentrate during chronic infection. It is not known, however, if antigen-specific CD8+ T cells are excluded gradually as pathogenesis progresses from early to chronic phase, or this phenomenon occurs from the beginning infection. In this study we determined that SIV-specific CD8+ T cells were largely excluded from follicles during early infection, we also found that within follicles, they were entirely absent in 60% of the germinal centers (GCs) examined. Furthermore, levels of SIV-specific CD8+ T cells in follicular but not extrafollicular areas significantly correlated inversely with levels of viral RNA+ cells. In addition, subsets of follicular SIV-specific CD8+ T cells were activated and proliferating and expressed the cytolytic protein perforin. These studies suggest that a paucity of SIV-specific CD8+ T cells in follicles and complete absence within GCs during early infection may set the stage for the establishment of persistent chronic infection.

Associations between endocrine disrupting chemicals and equine metabolic syndrome phenotypes

Equine Metabolic Syndrome (EMS) is characterized by abnormalities in insulin regulation, increased adiposity and laminitis, and has several similarities to human metabolic syndrome. A large amount of environmental variability in the EMS phenotype is not explained by commonly measured factors (diet, exercise, and season), suggesting that other environmental factors play a role in EMS development. Endocrine disrupting chemicals (EDCs) are associated with metabolic syndrome and other endocrine abnormalities in humans. This led us to hypothesize that EDCs are detectable in horse plasma and play a role in the pathophysiology of EMS. EDCs acting through the aryl hydrocarbon and estrogen receptors, were measured in plasma of 301 horses from 32 farms. The median (range) TEQ (2,3,7,8-TCDD equivalent) and EEQ (17β-estradiol equivalent) were 19.29 pg/g (0.59-536.36) and 10.50 pg/ml (4.35-15000.00), respectively. TEQ was negatively associated with plasma fat extracted and batch analyzed. EEQ was positively associated with pregnancy and batch analyzed, and negatively associated with being male and superfund score ≤100 miles of the farm. Of particular interest, serum glucose and insulin, glucose and insulin post oral sugar challenge, and leptin concentrations were associated with EEQ, and serum triglyceride concentration was associated with TEQ. Overall, we demonstrated that EDCs are present in the plasma of horses and may explain some of the environmental variability in measured EMS phenotypes. This is the first example of EDCs being associated with clinical disease phenotype components in domestic animals.

Mycoplasma hyorhinis and Mycoplasma hyosynoviae dual detection patterns in dams and piglets

Mycoplasma hyorhinis and M. hyosynoviae are agents associated with arthritis in pigs. This study investigated the tonsillar detection patterns of M. hyorhinis and M. hyosynoviae in a swine population with a history of lameness. The plausibility of dual PCR detection of these agents in dams at one and three weeks post-farrowing and their offspring at the same time was determined. The association between M. hyorhinis and M. hyosynoviae detection in piglets and potential development of lameness in wean-to-finish stages was evaluated by correlating individual piglet lameness scores and PCR detection in tonsils. Approximately 40% of dams were detected positive for M. hyorhinis and M. hyosynoviae at both one and three weeks post-farrowing. In first parity dams, M. hyorhinis was detected in higher proportions (57.1% and 73.7%) at both weeks of sampling compared to multi-parity dams. A lower proportion of first parity dams (37.5%) were detected positive at week one with M. hyosynoviae and an increase in this proportion to 50% was identified in week three. Only 8.3% of piglets were detected positive for M. hyorhinis in week one compared to week three (50%; p<0.05). The detection of M. hyosynoviae was minimal in piglets at both weeks of sampling (0% and 0.9%). Lameness was scored in pigs 5-22 weeks of age, with the highest score observed at week 5. The correlation between PCR detection and lameness scores revealed that the relative risk of developing lameness post-weaning was significantly associated with detection of M. hyorhinis in piglets at three weeks of age (r = 0.44; p<0.05).The detection pattern of M. hyorhinis and M. hyosynoviae in dams did not reflect the detection pattern in piglets. Results of this study suggest that positive detection of M. hyorhinis in piglets pre-weaning could act as a predictor for lameness development at later production stages.

Assessment of eosinophils in gastrointestinal inflammatory disease of dogs

BACKGROUND

Accurate identification of eosinophils in the gastrointestinal (GI) tract of dogs with eosinophilic GI disease (EGID) by histological evaluation is challenging. The currently used hematoxylin and eosin (H&E) staining method detects intact eosinophils but does not detect degranulated eosinophils, thus potentially underrepresenting the number of infiltrating eosinophils.

OBJECTIVE

To develop a more sensitive method for identifying and quantifying both intact and degranulated eosinophils to diagnose EGID more accurately.

METHODS

Endoscopically obtained paraffin-embedded intestinal biopsy specimens from dogs with GI signs were examined. The study groups were dogs with eosinophilic enteritis (EE), lymphoplasmacytic and mixed enteritis, and control dogs with GI signs but no histologic changes on tissue sections. Consecutive sections were immunolabeled with monoclonal antibodies (mAbs) against the eosinophil granule protein eosinophil peroxidase (Epx) and stained by H&E, respectively. The number of eosinophils was manually quantified and classified as intact or degranulated.

RESULTS

The number of intact eosinophils detected in Epx mAb-labeled duodenal sections was significantly higher compared with that in H&E-stained sections, with a similar relationship noted in the colon and stomach. The Epx mAb allowed the unique assessment of eosinophil degranulation. The number of intact and degranulated eosinophils was significantly higher in duodenal lamina propria of the EE and mixed group compared to the control group.

CONCLUSION

Immunohistochemical detection of Epx provides a more precise method to detect GI tract eosinophils compared to H&E staining and could be used as an alternative and reliable diagnostic tool for assessment of biopsy tissues from dogs with EGID.

Metabolic perturbations in Welsh Ponies with insulin dysregulation, obesity, and laminitis

Background

Metabolomics, the study of small‐molecule metabolites, has increased understanding of human metabolic diseases, but has not been used to study equine metabolic syndrome (EMS).

Objectives

(1) To examine the serum metabolome of Welsh Ponies with and without insulin dysregulation before and during an oral sugar test (OST). (2) To identify differences in metabolites in ponies with insulin dysregulation, obesity, or history of laminitis.

Animals

Twenty Welsh Ponies (mean ± SD; 13.8 ± 9.0 years) classified as non‐insulin dysregulated [CON] (n = 10, insulin < 30 mU/L) or insulin dysregulated [ID] (n = 10, insulin > 60 mU/L) at 75 minutes after administration of Karo syrup, obese (n = 6) or nonobese (n = 14), and history of laminitis (n = 9) or no history of laminitis (n = 11).

Methods

Case‐control study. Metabolomic analysis was performed on serum obtained at 0 minutes (baseline) and 75 minutes during the OST. Data were analyzed with multivariable mixed linear models with significance set at P ≤ .05.

Results

Metabolomic analysis of 646 metabolites (506 known) detected significant metabolite differences. At baseline, 55 metabolites (insulin response), 91 metabolites (obesity status), and 136 metabolites (laminitis history) were different. At 75 minutes, 51 metabolites (insulin response), 102 metabolites (obesity status), and 124 metabolites (laminitis history) were different.

Conclusions and Clinical Importance

Use of metabolomics could have diagnostic utility for early detection of EMS and provide new knowledge regarding the pathophysiology of metabolic perturbations associated with this condition that might lead to improved clinical management.

DNM1 mutation status, sex, and sterilization status of a cohort of Labrador retrievers with and without cranial cruciate ligament rupture

Background

Exercise-induced collapse (EIC) due to DNM1 mutation and rupture of the cranial cruciate ligament are both common syndromes in the Labrador retriever breed. A cohort of 313 Labradors was recruited based on their CCLR status and were subsequently genetically tested for EIC. Epidemiological aspects of the cohort were also described, including sex, sterilization status, and age at sterilization.

Results

No sex difference was observed in dogs susceptible to EIC (homozygous for the mutant genotype) compared to dogs not susceptible to EIC (heterozygotes and dogs homozygous for the normal genotype). No evidence for association was detected between CCLR status and EIC status (p =0.357), although the sample cohort was not of sufficient size to entirely rule out an association. A significant difference (p = 0.031) was observed in the sex distribution of dogs affected with CCLR compared to those without CCLR. An increased number of female CCLR cases were observed compared to the number of female controls; male CCLR cases and controls were approximately the same number. When CCLR status was examined in each sex, no significant differences were observed between those that were sterilized and those that weren’t. However, for female dogs that were sterilized, CCLR cases were significantly higher in dogs sterilized at one year of age or younger compared to those sterilized when over the age of one year (p = 0.0021, OR 4.30, 95% CI 1.55–12.72); for males, this finding was suggestive, but not statistically significant (p = 0.0913, OR 3.57, 95% CI 0.809–14.476).

Conclusions

CCLR is not associated with a large increase in EIC occurrence. Statistically, these two syndromes cannot be proven to be unrelated; however, concomitant occurrence of CCLR and EIC in Labrador retrievers is rare, despite the high prevalence of both syndromes in this breed. Epidemiological findings suggest that females may be over-represented in CCLR cases and that early sterilization (≤1 year) may increase the risk of Labradors developing CCLR later in life (particularly in females). These results should be considered preliminary and require confirmation in larger populations of Labrador retrievers.

Assessment of eosinophil peroxidase as a potential diagnostic and prognostic marker in dogs with inflammatory bowel disease

OBJECTIVE To evaluate a method for identifying intact and degranulated eosinophils in the small intestine of dogs with inflammatory bowel disease (IBD) by use of a monoclonal antibody (mAb) against eosinophil peroxidase (EPX). ANIMALS 11 untreated dogs with IBD, 5 dogs with IBD treated with prednisolone, and 8 control dogs with no clinical evidence of gastrointestinal tract disease and no immunosuppressive treatment. PROCEDURES 4-μm-thick sections of paraffin-embedded tissues from necropsy specimens were immunostained with EPX mAb. Stained intact and degranulated eosinophils in consecutive microscopic fields (400X magnification) of the upper (villus tips) and lower (between the muscularis mucosae and crypts) regions of the lamina propria of the jejunum were manually counted. RESULTS Compared with control and treated IBD dogs, untreated IBD dogs had a significantly higher number of degranulated eosinophils in the lower region of the lamina propria. However, no significant differences were detected in the number of intact eosinophils in this region among groups. In the upper region of the lamina propria, untreated IBD dogs had a significantly higher number of degranulated and intact eosinophils, compared with control and treated IBD dogs. Number of degranulated and intact eosinophils did not differ significantly between control and treated IBD dogs. CONCLUSIONS AND CLINICAL RELEVANCE Immunohistologic analysis with EPX mAb yielded prominent granule staining that allowed reliable morphological identification of degranulated and intact eosinophils, which may provide a strategy for quantitative and selective evaluation of eosinophils in gastrointestinal biopsy specimens and a potential method to diagnose IBD and evaluate treatment outcome.

Proteome Scale-Protein Turnover Analysis Using High Resolution Mass Spectrometric Data from Stable-Isotope Labeled Plants

Protein turnover is an important aspect of the regulation of cellular processes for organisms when responding to developmental or environmental cues. The measurement of protein turnover in plants, in contrast to that of rapidly growing unicellular organismal cultures, is made more complicated by the high degree of amino acid recycling, resulting in significant transient isotope incorporation distributions that must be dealt with computationally for high throughput analysis to be practical. An algorithm in R, ProteinTurnover, was developed to calculate protein turnover with transient stable isotope incorporation distributions in a high throughput automated manner using high resolution MS and MS/MS proteomic analysis of stable isotopically labeled plant material. ProteinTurnover extracts isotopic distribution information from raw MS data for peptides identified by MS/MS from data sets of either isotopic label dilution or incorporation experiments. Variable isotopic incorporation distributions were modeled using binomial and beta-binomial distributions to deconvolute the natural abundance, newly synthesized/partial-labeled, and fully labeled peptide distributions. Maximum likelihood estimation was performed to calculate the distribution abundance proportion of old and newly synthesized peptides. The half-life or turnover rate of each peptide was calculated from changes in the distribution abundance proportions using nonlinear regression. We applied ProteinTurnover to obtain half-lives of proteins from enriched soluble and membrane fractions from Arabidopsis roots.

Genome-wide association analysis of osteochondrosis of the tibiotarsal joint in Norwegian Standardbred trotters

Osteochondrosis (OC), a disturbance in the process of endochondral ossification, is by far the most important equine developmental orthopaedic disease and is also common in other domestic animals and humans. The purpose of this study was to identify quantitative trait loci (QTL) associated with osteochondrosis dissecans (OCD) at the intermediate ridge of the distal tibia in Norwegian Standardbred (SB) using the Illumina Equine SNP50 BeadChip whole-genome single-nucleotide polymorphism (SNP) assay. Radiographic data and blood samples were obtained from 464 SB yearlings. Based on the radiographic examination, 162 horses were selected for genotyping; 80 of these were cases with an OCD at the intermediate ridge of the distal tibia, and 82 were controls without any developmental lesions in the joints examined. Genotyped horses descended from 22 sires, and the number of horses in each half-sib group ranged from 3 to 14. The population structure necessitated statistical correction for stratification. When conducting a case-control genome-wide association study (GWAS), mixed-model analyses displayed regions on chromosomes (Equus callabus chromosome - ECA) 5, 10, 27 and 28 that showed moderate evidence of association (P ≤ 5 × 10(-5); this P-value is uncorrected i.e. not adjusted for multiple comparisons) with OCD in the tibiotarsal joint. Two SNPs on ECA10 represent the most significant hits (uncorrected P=1.19 × 10(-5) in the mixed-model). In the basic association (chi-square) test, these SNPs achieved statistical significance with the Bonferroni correction (P=0.038) and were close in the permuted logistic regression test (P=0.054). Putative QTL on ECA 5, 10, 27 and 28 represent interesting areas for future research, validation studies and fine mapping of candidate regions. Results presented here represent the first GWAS of OC in horses using the recently released Illumina Equine SNP50 BeadChip.

Intra-farm risk factors for Mycoplasma hyopneumoniae colonization at weaning age

The objective of this study was to identify intra-farm risk factors that affected the colonization with Mycoplasma hyopneumoniae at weaning age. Three farrow-to-wean farms were visited at least 5 times each. An average of 54 piglets were sampled at each visit and assayed by means of real-time PCR in nasal swabs. The proportion of PCR positive piglets was evaluated as a response to several variables including dam's PCR status, piglet serological status, and local climatic conditions during the lactation period, as well as other factors. All piglets at weaning age were negative to M. hyopneumoniae in 2 of the 3 farms. M. hyopneumoniae positive piglets were demonstrated in 5 of 7 weaning groups in 1 farm. The proportion of M. hyopneumoniae positive piglets in each weaning group at the positive farm was correlated with the proportion of positive dams in the group. The prevalence of M. hyopneumoniae at weaning increased with the piglet's age in the groups where at least one dam was positive. These results highlight the influence of the sow in the sow-to-piglet colonization process, as previously reported, and contribute to a more comprehensive understanding of the epidemiology of M. hyopneumoniae infections.

Estimation of body weight and development of a body weight score for adult equids using morphometric measurements

Excessive BW has become a major health issue in the equine (Equus caballus) industry. The objectives were to determine if the addition of neck circumference and height improved existing BW estimation equations, to develop an equation for estimation of ideal BW, and to develop a method for assessing the likelihood of being overweight in adult equids. Six hundred and twenty-nine adult horses and ponies who met the following criteria were measured and weighed at 2 horse shows in September 2011 in Minnesota: age ≥ 3 yr, height ≥ 112 cm, and nonpregnant. Personnel assessed BCS on a scale of 1 to 9 and measured wither height at the third thoracic vertebra, body length from the point of shoulder to the point of the buttock, neck and girth circumference, and weight using a portable livestock scale. Individuals were grouped into breed types on the basis of existing knowledge and were confirmed with multivariate ANOVA analysis of morphometric measurements. Equations for estimated and ideal BW were developed using linear regression modeling. For estimated BW, the model was fit using all individuals and all morphometric measurements. For ideal BW, the model was fit using individuals with a BCS of 5; breed type, height, and body length were considered as these measurements are not affected by adiposity. A BW score to assess the likelihood of being overweight was developed by fitting a proportional odds logistic regression model on BCS using the difference between ideal and estimated BW, the neck to height ratio, and the girth to height ratio as predictors; this score was then standardized using the data from individuals with a BCS of 5. Breed types included Arabian, stock, and pony. Mean (± SD) BCS was 5.6 ± 0.9. BW (kg) was estimated by taking [girth (cm)(1.48)6 × length (cm)(0.554) × height (cm)(0.599) × neck (cm)(0.173)]/3,596, 3,606, and 3,441 for Arabians, ponies, and stock horses, respectively (R(2) = 0.92; mean-squared error (MSE) = 22 kg). Ideal BW (kg) was estimated by taking [length (cm) × 2.8] + [height (cm) × 4.2] - 611, 606, and 577 for Arabians, ponies, and stock horses, respectively (R(2) = 0.86; MSE = 24). Equids with a BCS of ≥ 7 had a greater likelihood of being overweight, and the model suggested cutoffs at the 48th and 83rd percentiles for underweight and overweight individuals, respectively. Morphometric measurements were successfully used to develop equid BW-related equations.

Genetic risk factors for insidious equine recurrent uveitis in Appaloosa horses

Appaloosa horses are predisposed to equine recurrent uveitis (ERU), an immune-mediated disease characterized by recurring inflammation of the uveal tract in the eye, which is the leading cause of blindness in horses. Nine genetic markers from the ECA1 region responsible for the spotted coat color of Appaloosa horses, and 13 microsatellites spanning the equine major histocompatibility complex (ELA) on ECA20, were evaluated for association with ERU in a group of 53 Appaloosa ERU cases and 43 healthy Appaloosa controls. Three markers were significantly associated (corrected P-value <0.05): a SNP within intron 11 of the TRPM1 gene on ECA1, an ELA class I microsatellite located near the boundary of the ELA class III and class II regions and an ELA class II microsatellite located in intron 1 of the DRA gene. Association between these three genetic markers and the ERU phenotype was confirmed in a second population of 24 insidious ERU Appaloosa cases and 16 Appaloosa controls. The relative odds of being an ERU case for each allele of these three markers were estimated by fitting a logistic mixed model with each of the associated markers independently and with all three markers simultaneously. The risk model using these markers classified ~80% of ERU cases and 75% of controls in the second population as moderate or high risk, and low risk respectively. Future studies to refine the associations at ECA1 and ELA loci and identify functional variants could uncover alleles conferring susceptibility to ERU in Appaloosa horses.

Coat color genotypes and risk and severity of melanoma in gray quarter horses

BACKGROUND

Both graying and melanoma formation in horses have recently been linked to a duplication in the STX17 gene. This duplication, as well as a mutation in the ASIP gene that increases MC1R pathway signaling, affects melanoma risk and severity in gray horses.

OBJECTIVE

To determine if melanoma susceptibility in gray Quarter Horses (QH) is lower than gray horses from other breeds because of decreased MC1R signaling resulting from a high incidence of the MC1R chestnut coat color allele in the QH population.

ANIMALS

A total of 335 gray QH with and without dermal melanomas.

METHODS

Blood or hair root samples were collected from all horses for DNA extraction and genotyping for STX17, ASIP, and MC1R genotypes. Age, sex, and external melanoma presence and grade were recorded. The effect of age and genotype on melanoma presence and severity was evaluated by candidate gene association.

RESULTS

Melanoma prevalence (16%) and grade (0.35) in this QH cohort was lower than that reported in other breeds. Age was significantly associated with melanoma prevalence (P = 5.28 × 10(-11)) and severity (P = 2.2 × 10(-13)). No significant effect of MC1R genotype on melanoma prevalence or severity was identified. An effect of ASIP genotype on melanoma risk was not detected. Low STX17 homozygosity precluded evaluation of the gray allele effect.

CONCLUSION AND CLINICAL IMPORTANCE

Melanoma prevalence and severity is lower in this population of gray QH than what is reported in other breeds. This could be because of the infrequent STX17 homozygosity, a mitigating effect of the MC1R mutation on ASIP potentiation of melanoma, other genes in the MC1R signaling pathway, or differences in breed genetic background.

Equine developmental orthopaedic diseases--a genome-wide association study of first phalanx plantar osteochondral fragments in Standardbred trotters

Palmar/plantar osteochondral fragments (POF) in fetlock joints commonly affect and influence the athletic performance of horses. In this study, we used the Equine SNP50 BeadChip® to perform a genome-wide association study of metatarsophalangeal POF in 176 Norwegian Standardbred trotter yearlings. Putative quantitative trait loci (QTL) for medial and/or lateral POF, and medial POF only were identified on ECA1, 2, 7, 9 and 31, whereas for lateral POF, only on ECA7, 11, 27 and X. The moderate number of QTL evidences a complex inheritance and suggests various genes controlling POF development in medial and lateral locations.

Genome-wide analysis reveals selection for important traits in domestic horse breeds

Intense selective pressures applied over short evolutionary time have resulted in homogeneity within, but substantial variation among, horse breeds. Utilizing this population structure, 744 individuals from 33 breeds, and a 54,000 SNP genotyping array, breed-specific targets of selection were identified using an F(ST)-based statistic calculated in 500-kb windows across the genome. A 5.5-Mb region of ECA18, in which the myostatin (MSTN) gene was centered, contained the highest signature of selection in both the Paint and Quarter Horse. Gene sequencing and histological analysis of gluteal muscle biopsies showed a promoter variant and intronic SNP of MSTN were each significantly associated with higher Type 2B and lower Type 1 muscle fiber proportions in the Quarter Horse, demonstrating a functional consequence of selection at this locus. Signatures of selection on ECA23 in all gaited breeds in the sample led to the identification of a shared, 186-kb haplotype including two doublesex related mab transcription factor genes (DMRT2 and 3). The recent identification of a DMRT3 mutation within this haplotype, which appears necessary for the ability to perform alternative gaits, provides further evidence for selection at this locus. Finally, putative loci for the determination of size were identified in the draft breeds and the Miniature horse on ECA11, as well as when signatures of selection surrounding candidate genes at other loci were examined. This work provides further evidence of the importance of MSTN in racing breeds, provides strong evidence for selection upon gait and size, and illustrates the potential for population-based techniques to find genomic regions driving important phenotypes in the modern horse.

Genome-wide association study implicates testis-sperm specific FKBP6 as a susceptibility locus for impaired acrosome reaction in stallions

Impaired acrosomal reaction (IAR) of sperm causes male subfertility in humans and animals. Despite compelling evidence about the genetic control over acrosome biogenesis and function, the genomics of IAR is as yet poorly understood, providing no molecular tools for diagnostics. Here we conducted Equine SNP50 Beadchip genotyping and GWAS using 7 IAR–affected and 37 control Thoroughbred stallions. A significant (P<6.75E-08) genotype–phenotype association was found in horse chromosome 13 in FK506 binding protein 6 (FKBP6). The gene belongs to the immunophilins FKBP family known to be involved in meiosis, calcium homeostasis, clathrin-coated vesicles, and membrane fusions. Direct sequencing of FKBP6 exons in cases and controls identified SNPs g.11040315G>A and g.11040379C>A (p.166H>N) in exon 4 that were significantly associated with the IAR phenotype both in the GWAS cohort (n = 44) and in a large multi-breed cohort of 265 horses. All IAR stallions were homozygous for the A-alleles, while this genotype was found only in 2% of controls. The equine FKBP6 was exclusively expressed in testis and sperm and had 5 different transcripts, of which 4 were novel. The expression of this gene in AC/AG heterozygous controls was monoallelic, and we observed a tendency for FKBP6 up-regulation in IAR stallions compared to controls. Because exon 4 SNPs had no effect on the protein structure, it is likely that FKBP6 relates to the IAR phenotype via regulatory or modifying functions. In conclusion, FKBP6 was considered a susceptibility gene of incomplete penetrance for IAR in stallions and a candidate gene for male subfertility in mammals. FKBP6 genotyping is recommended for the detection of IAR–susceptible individuals among potential breeding stallions. Successful use of sperm as a source of DNA and RNA propagates non-invasive sample procurement for fertility genomics in animals and humans.

Impaired acrosomal reaction (IAR) of sperm causes male subfertility in humans and animals, and currently the molecular causes of the condition are not known. Here we report the mapping, identification, and functional analysis of a susceptibility locus for IAR in stallions. The candidate region was mapped to horse chromosome 13 by SNP genotyping and GWAS of 7 IAR affected and 44 control Thoroughbred stallions. Re-sequencing and case-control analysis of functionally relevant candidate genes in the region identified FKBP6 gene as a significantly associated locus. The association was confirmed by genotyping 265 male horses of multiple breeds. FKBP6 belongs to the immunophilins FKBP family known to be involved in meiosis, calcium homeostasis, clathrin-coated vesicles, and membrane fusions. We showed that the equine FKBP6 is exclusively and monoallelically expressed in testis and sperm and has 5 different transcripts, of which 4 were novel. Overall, FKBP6 was considered a susceptibility gene of incomplete penetrance for IAR in stallions and a candidate gene for male subfertility in other mammals. Successful use of sperm as a source of DNA and RNA propagates non-invasive sample procurement for fertility genomics in animals and humans.

Genetic mapping of recurrent exertional rhabdomyolysis in a population of North American Thoroughbreds

Recurrent exertional rhabdomyolysis is a heritable disorder that results in painful skeletal muscle cramping with exercise in up to 10% of all Thoroughbred racehorses. Here, we report a genome-wide association study with 48 282 SNPs analyzed among 48 case and 37 control Thoroughbreds. The most significant SNPs spanned approximately 13 Mb on ECA16, and the P-value of the most significant SNP after correcting for population structure was 8.0 × 10(-6) . This region on ECA16 was further evaluated by genotyping 247 SNPs in both the initial population and a second population of 34 case and 98 control Thoroughbreds. Several SNPs across the 13-Mb region on ECA16 showed significance when each population was analyzed separately; however, the exact positions of the most significant SNPs within this region on ECA16 varied between populations. This variability in location may be attributed to lack of power owing to insufficient sample sizes within each population individually, or to the relative distribution of long, conserved haplotypes, characteristic of the Thoroughbred breed. Future genome-wide association studies with additional horses would likely improve the power to resolve casual loci located on ECA16 and increase the likelihood of detecting any additional loci on other chromosomes contributing to disease susceptibility.

Measuring the turnover rates of Arabidopsis proteins using deuterium oxide: an auxin signaling case study

Rapid environmental responses in plants rely on endogenous signaling mechanisms, which in many cases are mediated by changes in protein turnover rates. It is therefore necessary to develop methods for measuring protein dynamics that monitor large sets of plant proteins to begin to apply a systems biology approach to the study of plant behavior. The use of stable isotope labeling strategies that are adaptable to proteomic methods is particularly attractive for this purpose. Here, we explore one example of such methods that is particularly suitable for plants at the seedling stage, where measurement of amino acid and protein turnover rates is accomplished using a heavy water labeling strategy. The method is backed by microarray evaluation to define its feasibility for specific experimental approaches, and the CULLIN-ASSOCIATED AND NEDDYLATION DISSOCIATED 1 (CAND1) and TRANSPORT INHIBITOR RESPONSE 1 (TIR1) proteins are used to illustrate the potential utility in understanding hormonal signaling regulation. These studies provide insight not only into the potential utility of the method, but also address possible areas of concern regarding the use of heavy water labeling during plant growth. These considerations suggest a prescription for specific experimental designs that minimize interference resulting from the induction of treatment-specific gene expression in the results obtained.

Experimental support for multiple-locus complementary sex determination in the parasitoid Cotesia vestalis

Despite its fundamental role in development, sex determination is highly diverse among animals. Approximately 20% of all animals are haplodiploid, with haploid males and diploid females. Haplodiploid species exhibit diverse but poorly understood mechanisms of sex determination. Some hymenopteran insect species exhibit single-locus complementary sex determination (sl-CSD), where heterozygosity at a polymorphic sex locus initiates female development. Diploid males are homozygous at the sex locus and represent a genetic load because they are inviable or sterile. Inbreeding depression associated with CSD is therefore expected to select for other modes of sex determination resulting in fewer or no diploid males. Here, we investigate an alternative, heretofore hypothetical, mode of sex determination: multiple-locus CSD (ml-CSD). Under ml-CSD, diploid males are predicted to develop only from zygotes that are homozygous at all sex loci. We show that inbreeding for eight generations in the parasitoid wasp Cotesia vestalis leads to increasing proportions of diploid males, a pattern that is consistent with ml-CSD but not sl-CSD. The proportion of diploid males (0.27 +/- 0.036) produced in the first generation of inbreeding (mother-son cross) suggests that two loci are likely involved. We also modeled diploid male production under CSD with three linked loci. Our data visually resemble CSD with linked loci because diploid male production in the second generation was lower than that in the first. To our knowledge, our data provide the first experimental support for ml-CSD.