Lipid metabolism and hyperlipidemia in dogs

Prognostic value of dyslipidemia for sick dogs hospitalized in the intensive care unit of a veterinary teaching hospital

OBJECTIVE To evaluate the lipidemia status and serum concentrations of cholesterol and triglycerides of dogs when initially examined for hospitalization in the intensive care unit (ICU) of a veterinary teaching hospital and to determine whether these variables were predictive of survival to hospital discharge. DESIGN Retrospective cohort study. ANIMALS 549 client-owned sick (n = 398) and healthy (151) dogs. PROCEDURES Medical records of sick dogs hospitalized in the ICU at a veterinary teaching hospital between January 1, 2012, and September 30, 2015, and of healthy dogs evaluated at the teaching hospital during the same time frame were reviewed. Data collection included signalment, results of initial physical and clinicopathologic examinations, treatments, diagnosis, and survival to hospital discharge. Lipidemia status and serum concentrations of cholesterol and triglycerides were compared between healthy and sick dogs and between sick dogs that did and did not survive to hospital discharge. Regression analysis was performed to determine whether these variables were predictive of survival to hospital discharge in dogs. RESULTS Factors associated with increased odds of sick dogs not surviving to hospital discharge were hypocholesterolemia (OR, 1.87; 95% confidence interval [CI], 1.04 to 3.34), hypertriglyceridemia (OR, 3.20; 95% CI, 2.00 to 5.13), and concurrent hypocholesterolemia and hypertriglyceridemia (OR, 55.7; 95% CI, 3.2 to 959.6) at the time of initial evaluation. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that hypocholesterolemia and hypertriglyceridemia, alone or in combination, at initial examination were negative prognostic indicators for survival of dogs hospitalized in the ICU and that these conditions were easily identified with routine serum clinicopathologic analyses. (J Am Vet Med Assoc 2019;254:699-709).

Epigallocatechin-3-gallate activates the AMP-activated protein kinase signaling pathway to reduce lipid accumulation in canine hepatocytes

Epigallocatechin-3-gallate (EGCG) plays a crucial role in hepatic lipid metabolism. However, the underlying regulatory mechanism of hepatic lipid metabolism by EGCG in canine is unclear. Primary canine hepatocytes were treated with EGCG (0.01, 0.1, or 1 μM) and BML-275 (an AMP-activated protein kinase [AMPK] inhibitor) to study the effects of EGCG on the gene and protein expressions associated with AMPK signaling pathway. Data showed that treatment with EGCG had greater activation of AMPK, as well as greater expression levels and transcriptional activity of peroxisome proliferator activated receptor-α (PPARα) along with upregulated messenger RNA (mRNA) abundance and protein abundance of PPARα-target genes. EGCG decreased the expression levels and transcriptional activity of sterol regulatory element-binding protein 1c (SREBP-1c) along with downregulated mRNA abundance and protein abundance of SREBP-1c target genes. Of particular interest, exogenous BML-275 could reduce or eliminate the effects of EGCG on lipid metabolism in canine hepatocytes. Furthermore, the content of triglyceride was significantly decreased in the EGCG-treated groups. These results suggest that EGCG might be a potential agent in preventing high-fat diet-induced lipid accumulation in small animals.

Development of Novel Continuous and Interval Exercise Programs by Applying the FITT-VP Principle in Dogs

Although proper exercise training induces positive physiological effects, improper exercise can lead to injury, fatigue, and poor performance. The frequency, intensity, time/duration, type, volume, and progression (FITT-VP) are the essential components of exercise training to maintain or improve physical fitness and health. The purpose of this study was to develop specific exercise programs by applying the FITT-VP principle and to examine the effects on heart rate (HR) and hematological and biochemical parameters in dogs. The healthy male Beagles (n = 4) included in this study performed continuous and interval exercises, comprising 12 protocols. The HR monitoring elicited an affirmative response to activities but varied depending on the protocols. The hematologic parameters (e.g., red blood cell count, white blood cell count, hemoglobin, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration) were within the reference ranges both before and after exercise. The creatine kinase level significantly increased, and the cholesterol level decreased after exercises. In conclusion, the continuous and interval exercise program elicits an appropriate HR reaction, has no adverse effects on the serum parameters, and provides valuable insight for healthcare in dogs.

Overexpression of miR-297b-5p protects against stearic acid-induced pancreatic β-cell apoptosis by targeting LATS2

Chronic exposure to high concentrations of stearic acid (C18:0) can result in β-cell dysfunction, leading to development of type 2 diabetes. However, the molecular mechanisms underlying the destructive effects of stearic acid on β-cells remain largely unknown. In this study, we aimed to investigate the role of miR-297b-5p on stearic acid-induced β-cell apoptosis. Differential expression of microRNAs (miRNAs) was assessed in a β-TC6 cell line exposed to stearic acid, palmitic acid, or a normal culture medium by high-throughput sequencing. The apoptosis rate was measured by flow cytometry after miR-297b-5p mimic/inhibitor transfection, and large-tumor suppressor kinase 2 (LATS2) was identified as a target of miR-297b-5p using a luciferase activity assay. In vivo, C57BL/6 mice were fed with normal and high-stearic-acid diet, respectively. Mouse islets were used for similar identification of miR-297b-5p and Lats2 in β-TC6 cell. We selected two differentially expressed miRNAs in stearic acid compared with those in the palmitic acid and control groups. miR-297b-5p expression was significantly lower in β-TC6 cells and mouse islets in stearic acid than in control group. Upregulation of miR-297b-5p alleviated the stearic acid-induced cell apoptosis and reduction in insulin secretion by inhibiting Lats2 expression in vitro. Meanwhile, silencing Lats2 significantly reversed the stearic acid-stimulated β-cell dysfunction in both β-TC6 cells and islets. Our findings indicate a suppressive role for miR-297b-5p in stearic acid-induced β-cell apoptosis, which may reveal a potential target for the treatment of β-cell dysfunction in the pathogenesis of type 2 diabetes.

Serum triglyceride and cholesterol concentrations and lipoprotein profiles in dogs with naturally occurring pancreatitis and healthy control dogs

BACKGROUND

Previous studies have reported an association between hyperlipidemia and pancreatitis in dogs, but details of this association remain poorly defined.

HYPOTHESIS/OBJECTIVES

To compare serum triglyceride and cholesterol concentrations and lipoprotein profiles between dogs with naturally occurring pancreatitis and healthy dogs.

ANIMALS

Seventeen dogs with a clinical diagnosis of pancreatitis (Group 1) and 53 healthy control dogs (Group 2).

METHODS

Prospective case-control study.

RESULTS

In Group 1, 3/17 dogs (18%) had hypertriglyceridemia whereas in Group 2, 4/53 dogs (7.5%) had hypertriglyceridemia (odds ratio [OR], 2.63; 95% confidence interval [CI], 0.52-13.14; P = .35). A significant difference was found in serum triglyceride concentrations between Group 1 (median, 67 mg/dL) and Group 2 (median, 54 mg/dL; P = .002). In Group 1, 4/17 dogs (24%) had hypercholesterolemia, whereas 1/53 (1.9%) dogs in Group 2 had hypercholesterolemia (OR, 16; 95% CI, 1.64-155.5; P = .01). No significant difference was found in serum cholesterol concentrations between Group 1 (median, 209 mg/dL) and Group 2 (median, 227 mg/dL; P = .56). Lipoprotein profiles were significantly different between Group 1 and Group 2 dogs (Eigenvalues, 0.6719; R² = 1.0; P = .001).

CONCLUSIONS AND CLINICAL IMPORTANCE

Most dogs with pancreatitis (>70%) had serum triglyceride and cholesterol concentrations within reference intervals. In the small percentage of dogs that had hypertriglyceridemia, hypercholesterolemia, or both, increases were mild. Important differences were identified in lipoprotein profiles between dogs with pancreatitis and healthy control dogs. Dogs with pancreatitis had higher low-density lipoprotein fractions and lower triglyceride-rich lipoprotein and high-density lipoprotein fractions than healthy dogs.

Exercise and Hyperlipidemia

Hyperlipidemia is one of the common pathological conditions of human, which occurs due to lipid metabolism disorder in the human body, resulting in serum lipid concentration beyond normal levels. Due to heredity, diet, nutrition, medicine, and other factors, the incidence of hyperlipidemia has been significantly enhanced and has become one of the most common pathological condition of the human. By introducing the background and pathogenesis of hyperlipidemia and the positive effects of exercise on a variety of related diseases, this chapter discusses the relationship between exercise and serum lipid concentration and the effects of different types of exercise on hyperlipidemia.

A retrospective analysis of lipid-laden aqueous humor in dogs: Thirty cases

OBJECTIVE

To describe the clinical presentation and outcome of canine patients that present with lipid-laden aqueous humor (LLA) and to evaluate its association with other ocular and systemic disorders.

METHODS

Medical records were identified and reviewed of 30 dogs presenting with clinical signs of LLA between 2013 and 2017 and compared to the canine referral population during the same time period. The percentage of dogs affected by LLA and potential risk factors were compared between groups.

RESULTS

There were 40 eyes in 30 dogs with LLA out of 8011 (0.4%) referrals. The mean age of dogs with LLA was significantly younger than dogs without LLA (P = .0334). Sex was not associated with LLA. Miniature Schnauzers were more likely to have LLA than mixed breeds (P < .0001). Incidence of LLA was significantly higher in eyes also affected by corneal ulceration (P = .0018) or phacoemulsification (P = .0001). Sixty-two percent and 51% of dogs with LLA had concurrent diabetes mellitus and hypertriglyceridemia, respectively. Average triglyceride level of dogs with LLA was 1087 mg/dL (±544) (reference 50-150 mg/dL) and average cholesterol level was 575 mg/dL (±232) (reference 125-300 mg/dL). Complete resolution of LLA was achieved in all dogs re-examined with an average of 20.2 days (range 4-175 days) after diagnosis. There were 6/30 dogs lost to follow-up. Recurrence of LLA occurred at least once in 4/24 dogs (16.7%) after resolution.

CONCLUSIONS

Lipid-laden aqueous humor occurs more frequently in Miniature Schnauzers. Corneal ulceration and phacoemulsification are risk factors. Complete resolution was seen in all cases with a low incidence of recurrence.

Thyroid and Lipid Status in Guide Dogs During Training: Effects of Dietary Protein and Fat Content

Nutrition plays a leading role that most influences thyroid response and energetic metabolism. Aim was to compare the effect of diet on thyroid and lipid status in guide dogs during a 12-weeks training period. Eight Labrador Retrievers were divided into two groups homogeneous for sex, age, body weight, and Body Condition Score (BCS) and fed two commercial diets one, HPF, characterized by low-carbohydrate/high-protein/high-fat (29%:39%:19% as-fed) and the other, LPF, by high-carbohydrate/low-protein/low-fat (50%:24%:12% as-fed) content. The serum thriiodothyronine (T₃), thyroxine (T₄), cholesterol (CHOL), triglycerides (TAGs) and non-esterified fatty acids (NEFA) were determined at Day 0, 28, 56, and 84, before the daily training. Statistical model included the effects of Diet (HPF vs. LPF) and Time (Day 0 to Day 84), and their interaction. In the HPF group, Diet significantly (p < 0.01) increased T₄, CHOL, and TAGs and decreased NEFA. In both groups, Time significantly (p < 0.05) increased T₄ and TAGs, CHOL at Day 28, and NEFA at Day 56. The interaction did not influence serum hormones and lipid pattern. The adjustments in thyroid and lipid responses to moderate exercise in HPF group were driven mainly by the nutrient composition of the diet in relation to the involvement of metabolic homeostasis.

Suspected Acute Respiratory Distress Syndrome Associated With the Use of Intravenous Lipid Emulsion Therapy in a Dog: A Case Report

A 12-year-old male neutered Bichon Frise presented to the Emergency Department for stupor and bradycardia after ingestion of chocolate covered 450 mg (90 mg/kg) tetrahydrocannabinol. The patient was hospitalized for supportive care, IV fluid therapy and monitoring in the intensive care unit. During hospitalization the patient became comatose and bradypneic. Treatment with intravenous lipid emulsion (ILE) therapy was instituted to accelerate toxin elimination, reduce the risk of complications related to progressive obtundation and shorten hospitalization time. Five hours after infusion, the patient developed severe respiratory distress and was ultimately euthanized. Post-mortem histologic evaluation of lung revealed severe pulmonary edema consistent with acute respiratory distress syndrome. There are infrequent reports of adverse effects associated with ILE therapy for toxicosis in veterinary medicine despite reports of complications such as acute respiratory distress syndrome in human literature. The purpose of this report is to describe the potential for a severe adverse event after treatment of a toxicosis with ILE therapy.

Effects of marked hypertriglyceridemia and lipid clearance techniques on canine biochemistry testing

Triglyceride concentrations in dogs with hyperlipidemic disorders can exceed concentrations used by assay manufacturers for interference testing. High-speed centrifugation or the polar solvent LipoClear reduce triglyceride concentrations, but efficacy requires evaluation in veterinary species. We determined the effect of marked hypertriglyceridemia on canine biochemistry testing; assessed the ability of high-speed centrifugation or LipoClear to correct lipemic interferences; and determined if LipoClear introduces inaccuracy into biochemistry assays. Fifteen pooled canine serum samples were aliquoted and spiked with equal volumes of water or Intralipid [triglyceride concentration 33.9 mmol/L (3,000 mg/dL)]. Intralipid aliquots underwent lipid removal by high-speed centrifugation or LipoClear treatment, and a water-spiked aliquot underwent LipoClear treatment. Biochemistry panels were performed using a Vitros 4600 chemistry analyzer. Results were compared by paired t-test or Wilcoxon test. Total observed errors were considered clinically acceptable if below veterinary allowable total error (TEa) guidelines. Statistically significant (p ≤ 0.05) interferences were introduced by Intralipid for 15 of 15 analytes. Median observed error exceeded TEa for potassium and enzymatic carbon dioxide, neither of which were identified by the manufacturer as susceptible to lipemic interference. After centrifugation, median observed error exceeded TEa for potassium and chloride. LipoClear treatment resulted in median errors that exceeded TEa for total protein, chloride, and phosphorus. Given that severe lipemia can occur in dogs with primary or secondary hyperlipidemia, veterinary laboratories should perform their own interference testing at triglyceride concentrations relevant to their patient population and provide this information to clinicians to ensure optimal case management.

Comparison of the systemic phospholipid profile in dogs diagnosed with idiopathic inflammatory bowel disease or food-responsive diarrhea before and after treatment

BACKGROUND

Inflammatory bowel disease (IBD) and food-responsive diarrhea (FRD) are common chronic enteropathies in dogs, of which the exact pathogenesis has not been fully understood. In people dyslipidemia has been reported in patients with IBD, and potential therapeutic benefits of polyunsaturated fatty acids (PUFA) in the treatment of IBD have been investigated. Studies on the phospholipid profile in dogs with IBD and FRD are still lacking.

AIM

To investigate the systemic phospholipid profile of dogs with IBD or FRD and to evaluate possible differences in phospholipids before and after treatment.

METHODS

The phospholipids in whole blood and EDTA plasma of 32 dogs diagnosed with either IBD (n = 16) or FRD (n = 16) were analyzed by hydrophilic interaction liquid chromatography (HILIC) prior to and after initiation of treatment, which included an elimination diet enriched with PUFAs.

RESULTS

A clear separation of the phospholipids between whole blood and plasma was demonstrated on principal component analysis plots. In addition to the type of specimen, treatment and disease severity were the most significant factors determining the variance of the phospholipid profile. An increase in lysolipids was observed after treatment. The phosphatidylcholine (PC) species changed from PC 38:4 before treatment to mainly lysophosphatidylcholine 18:0 after treatment. Furthermore, several differences in the abundance of individual phospholipids were identified between dogs with IBD and dogs with FRD and between treatment statuses using random forest analysis.

CONCLUSION

Significant variances were identified in the phospholipid profiles of dogs with IBD and FRD. These were particularly determined by type of specimen used, disease severity and treatment status. After treatment, a shift of phospholipid species towards lysophosphatidylcholine 18:0 was observed. Future studies should further investigate the role of lipids in the pathophysiology of IBD and FRD as well as their potential therapeutic benefits.

Changes in the Canine Plasma Lipidome after Short- and Long-Term Excess Glucocorticoid Exposure

Glucocorticoids (GCs) are critical regulators of metabolic control in mammals and their aberrant function has been linked to several pathologies. GCs are widely used in human and veterinary clinical practice as potent anti-inflammatory and immune suppressive agents. Dyslipidaemia is a frequently observed consequence of GC treatment, typified by increased lipolysis, lipid mobilization, liponeogenesis, and adipogenesis. Dogs with excess GC show hyperlipidaemia, hypertension, and a higher risk of developing type 2 diabetes mellitus, but the risk of developing atherosclerotic lesions is low as compared to humans. This study aimed to examine alterations in the canine plasma lipidome in a model of experimentally induced short-term and long-term GC excess. Both treatments led to significant plasma lipidome alterations, which were more pronounced after long-term excess steroid exposure. In particular, monohexosylceramides, phosphatidylinositols, ether phosphatidylcholines, acyl phosphatidylcholines, triacylglycerols and sphingosine 1-phosphates showed significant changes. The present study highlights the hitherto unknown effects of GCs on lipid metabolism, which will be important in the further elucidation of the role and function of GCs as drugs and in metabolic and cardiovascular diseases.

Indication of metabolic inflexibility to food intake in spontaneously overweight Labrador Retriever dogs

Background

Obesity in dogs is an increasing problem associated with morbidity, shortened life span and poor life quality. Overweight dogs exhibit postprandial hyperlipidaemia, highlighting the need to identify potential dysregulations in lipid metabolism. This study investigated metabolites related to lipid metabolism (i.e. acylcarnitines and taurine) and phospholipids in a feed-challenge test and aimed to identify metabolic variations in spontaneously overweight dogs. Twenty-eight healthy male Labrador Retriever dogs were included, 12 of which were classified as lean (body condition score (BCS) 4–5 on a 9-point scale) and 16 as overweight (BCS 6–8). After overnight fasting (14–17 h), fasting blood samples were collected and dogs were fed a high-fat meal followed by postprandial blood sample collection hourly for 4 h. Liquid chromatography-time of flight mass spectrometry (LC-TOFMS) was used to identify plasma metabolites and phospholipids. Multivariate models, mixed model repeated measures and linear regression analyses were used for data interpretation.

Results

In all dogs, propionylcarnitine, stearoylcarnitine and nine phospholipids increased in response to food intake, while vaccenylcarnitine decreased (P ≤ 0.005 for all). Overall, carnitine and acetylcarnitine signal areas in the feed-challenge test were lower in overweight dogs (P ≤ 0.004). Notably, fasting plasma acetylcarnitine was lower in overweight dogs than in lean dogs (P = 0.001) and it did not change in response to feeding. The latter finding was in contrast to the decreased acetylcarnitine signal area found in lean dogs at one hour postprandially (P < 0.0001). One fasting phosphatidylcholine (PCaa C38:4) was higher in prominently overweight dogs (BCS > 6) than in lean dogs (P < 0.05).

Conclusions

Plasma carnitine status was overall lower in spontaneously overweight dogs than in lean dogs in this cohort of healthy Labrador Retriever dogs, indicating a potential carnitine insufficiency in the overweight group. The acetylcarnitine response in overweight dogs indicated decreased fatty acid oxidation at fasting and metabolic inflexibility to food intake. Further studies on metabolic inflexibility and its potential role in the metabolism of overweight dogs are warranted.

Electronic supplementary material

The online version of this article (10.1186/s12917-019-1845-5) contains supplementary material, which is available to authorized users.

Evaluation of Hypertriglyceridemia as a Mediator Between Endocrine Diseases and Pancreatitis in Dogs

The role of hypertriglyceridemia (HTG) secondary to endocrine diseases in the occurrence of pancreatitis in dogs has not been fully investigated. The objective of the present study was to evaluate HTG as a mediator between endocrine diseases and pancreatitis in dogs. The study design was a retrospective case-control study. Medical records of dogs newly diagnosed with acutely presenting pancreatitis between 2012 and 2014 were reviewed for the presence or absence of hyperadrenocorticism (HAC), diabetes mellitus (DM), and hypothyroidism. A matched case-control analysis was performed, and the association between endocrine diseases and pancreatitis was evaluated using multiple logistic regression analysis. In dogs with pancreatitis, the odds of HAC (P &lt; .001) and DM (P &lt; .001) were 4.5 and 12.4 times that of dogs without pancreatitis, respectively. HTG significantly mediated the association between DM and pancreatitis but not between HAC and pancreatitis. Additional studies will be necessary to confirm these findings and to further elucidate the associations between endocrine diseases and pancreatitis.

Association of serum calprotectin (S100A8/A9) concentrations and idiopathic hyperlipidemia in Miniature Schnauzers

BACKGROUND

Idiopathic hyperlipidemia (IH) is a common condition in Miniature Schnauzers (MS). Studies in people have linked IH to low-grade inflammation, which plays an important role in the pathogenesis of IH complications. The role of inflammation in MS with IH is unknown.

OBJECTIVE

Evaluation of the inflammatory markers serum calprotectin and S100A12 in MS with IH and in response to dietary intervention for IH management.

ANIMALS

One-hundred fifty clinically healthy MS.

METHODS

Serum triglyceride, cholesterol, calprotectin, and S100A12 concentrations were measured before and after placing the dogs on an ultra-low fat diet.

RESULTS

Hypertriglyceridemia (HTGL, P < .001) and hypercholesterolemia (HCHOL, P = .01) were independently associated with increased serum calprotectin but not S100A12 concentrations. Compared to normolipidemic MS, serum calprotectin concentrations were significantly higher in MS with HTGL (P < .001) or combined hyperlipidemia (P = .02), but not those with isolated HCHOL (P = 1.0000). Presence (P = .005) and severity (P = .003) of HTGL and serum cholesterol concentrations (P = .04) decreased in MS with IH within 14-26 weeks after being placed on the ultra-low fat diet, but neither serum calprotectin nor S100A12 concentrations changed significantly with this dietary intervention.

CONCLUSIONS AND CLINICAL IMPORTANCE

Subclinical (low-grade) inflammation appears to be present in some MS with IH, and an ultra-low fat diet does not decrease serum concentrations of inflammatory proteins in those dogs. Whether this presumed inflammatory phenotype in MS with IH is associated with the development of IH complications (eg, insulin resistance) requires further research.

Comparative pathophysiology and management of protein-losing enteropathy

Protein‐losing enteropathy, or PLE, is not a disease but a syndrome that develops in numerous disease states of differing etiologies and often involving the lymphatic system, such as lymphangiectasia and lymphangitis in dogs. The pathophysiology of lymphatic disease is incompletely understood, and the disease is challenging to manage. Understanding of PLE mechanisms requires knowledge of lymphatic system structure and function, which are reviewed here. The mechanisms of enteric protein loss in PLE are identical in dogs and people, irrespective of the underlying cause. In people, PLE is usually associated with primary intestinal lymphangiectasia, suspected to arise from genetic susceptibility, or “idiopathic” lymphatic vascular obstruction. In dogs, PLE is most often a feature of inflammatory bowel disease (IBD), and less frequently intestinal lymphangiectasia, although it is not proven which process is the true driving defect. In cats, PLE is relatively rare. Review of the veterinary literature (1977‐2018) reveals that PLE was life‐ending in 54.2% of dogs compared to published disease‐associated deaths in IBD of <20%, implying that PLE is not merely a continuum of IBD spectrum pathophysiology. In people, diet is the cornerstone of management, whereas dogs are often treated with immunosuppression for causes of PLE including lymphangiectasia, lymphangitis, and crypt disease. Currently, however, there is no scientific, extrapolated, or evidence‐based support for an autoimmune or immune‐mediated mechanism. Moreover, people with PLE have disease‐associated loss of immune function, including lymphopenia, severe CD4+ T‐cell depletion, and negative vaccinal titers. Comparison of PLE in people and dogs is undertaken here, and theories in treatment of PLE are presented.

Comparative proteomic study of dog and human saliva

Saliva contains many proteins that have an important role in biological process of the oral cavity and is closely associated with many diseases. Although the dog is a common companion animal, the composition of salivary proteome and its relationship with that of human are unclear. In this study, shotgun proteomics was used to compare the salivary proteomes of 7 Thai village dogs and 7 human subjects. Salivary proteomes revealed 2,532 differentially expressed proteins in dogs and humans, representing various functions including cellular component organization or biogenesis, cellular process, localization, biological regulation, response to stimulus, developmental process, multicellular organismal process, metabolic process, immune system process, apoptosis and biological adhesion. The oral proteomes of dogs and humans were appreciably different. Proteins related to apoptosis processes and biological adhesion were predominated in dog saliva. Drug-target network predictions by STITCH Version 5.0 showed that dog salivary proteins were found to have potential roles in tumorigenesis, anti-inflammation and antimicrobial processes. In addition, proteins related to regeneration and healing processes such as fibroblast growth factor and epidermal growth factor were also up-regulated in dogs. These findings provide new information on dog saliva composition and will be beneficial for the study of dog saliva in diseased and health conditions in the future.

Fatty Acid Patterns Detected By Ambient Ionization Mass Spectrometry in Canine Invasive Urothelial Carcinoma From Dogs of Different Breeds

Background:

In early work ambient ionization mass spectrometry (MS) revealed lipid patterns distinguishing muscle invasive bladder cancer (invasive urothelial carcinoma, InvUC) from normal urothelium. A new ambient ionization MS approach, touch spray MS (TS-MS) can rapidly generate mass spectra in real time, potentially in a point-of-care setting. A tissue sample removed from a patient is touched by a probe, and mass spectra generated within seconds.

Objective:

To validate TS-MS methods using specimens from naturally-occurring InvUC in dogs where the cancer closely mimics the human condition, and to demonstrate proof-of-concept that TS-MS can elucidate lipid patterns distinguishing InvUC from normal urothelium.

Methods:

Samples of normal urothelium and InvUC from dogs of several breeds were analyzed by TS-MS with correlative histopathology across each sample. Results were compared to those obtained with desorption electrospray ionization mass spectrometry (DESI-MS), a more traditional method. Data were analyzed by Principal Component Analysis and Linear Discriminant Analysis.

Results:

Lipid patterns identified by TS-MS, as well as by DESI-MS, differed between InvUC and normal urothelium with m/z 281.5 (oleic acid) and m/z 563.5 (oleic acid dimer) substantially contributing to the differences. Using histologic diagnosis as the gold standard, TS-MS had a global prediction rate of 93%.

Conclusions:

TS-MS can be used to identify lipid patterns that differentiate canine InvUC from normal urothelium. Optimization of TS-MS could lead to a point-of-care approach to distinguish cancer from normal in ex vivo tissues in real time, and to define biochemical processes leading to cancer development and progression.

Clinofibrate improved canine lipid metabolism in some but not all breeds

The objectives of this study were to assess if Clinofibrate (CF) treatment improved lipid metabolism in dogs, and to clarify whether its efficacy is influenced by canine characteristics. We collected medical records of 306 dogs and performed epidemiological analyses. Lipid values of all lipoproteins were significantly decreased by CF medication, especially VLDL triglyceride (TG) concentration (mean reduction rate=54.82%). However, 17.65% of dogs showed drug refractoriness in relation to TG level, and Toy Poodles had a lower CF response than other breeds (OR=5.36, 95% CI=2.07-13.90). Therefore, our study suggests that genetic factors may have an effect on CF response, so genetic studies on lipid metabolism-related genes might be conducted to identify variations in CF efficacy.

Influence of feeding a fish oil-containing diet to mature, overweight dogs: Effects on lipid metabolites, postprandial glycaemia and body weight

The objective of this study was to determine the effect of feeding a fish oil (FO)-containing diet on lipid and protein metabolism, postprandial glycaemia and body weight (BW) of mature, overweight dogs. Seven female dogs were randomly assigned to one of two isonitrogenous and isocaloric diets, control (CO) or FO (FO), in a crossover design. Experimental periods were 69 day, separated by a washout period of 30 day. At the beginning of the experiment, and at 30 and 60 day of feeding the experimental diets, the dogs were infused with D-glucose (2 g/kg BW) through an intravenous catheter. Blood samples were collected for 3 hr to perform a glucose tolerance test. Nitrogen balance measurements began at 06:30 on d 63 of each experimental period and ended at 06:30 on d 69. On d 66 of each period, a single dose (7.5 mg/kg) of ¹⁵ N-glycine was administered orally for determination of protein turnover. Incremental area under the curve and glucose concentration at peak did not differ between treatments or among sampling days within treatment. Glucose half-life tended to decrease (p < .10) in the FO treatment on day 30 when compared to baseline (day 0). β-hydroxybutyrate, non-esterified fatty acid (NEFA) and triglycerides did not differ within or between treatments. Cholesterol decreased (p < .05) on the FO treatment on day 30, 60 and 69 when compared to day 0. High-density lipoprotein (HDL) decreased (p < .05) in the FO treatment on day 69 when compared to day 0. Body weight, food intake, faecal excretion, DM and N digestibilities, N balance and protein turnover were not different between diets. Overall, FO-containing diet decreases cholesterol in mature overweight dogs; however, further research is warranted to verify the effects of FO on glucose metabolism.

Therapy of Canine Hyperlipidemia with Bezafibrate

BACKGROUND

Bezafibrate (BZF) is effective in the treatment of hypertriglyceridemia in human patients, but there are no data on its use in dogs.

OBJECTIVE

To assess the safety of BZF in hyperlipidemic dogs and its efficacy in decreasing serum triglyceride (TG) and cholesterol (CHO) concentrations.

ANIMALS

Forty-six dogs, 26 females and 20 males, mean (±SD) age of 9 (±3) years, with TG ≥150 mg/dL (33 dogs also were hypercholesterolemic [>300 mg/dL]).

METHODS

Prospective, uncontrolled clinical trial. Dogs were treated with bezafibrate once daily, using 200 mg tablets at a dosage of 4-10 mg/kg (depending on body weight). Serum TG and CHO concentrations and alanine aminotransferase (ALT) and creatine kinase (CK) activity before and after 30 days of treatment were compared.

RESULTS

Sixteen dogs (34.8%) had primary hyperlipidemia, and 30 dogs (65.2%) had secondary hyperlipidemia (including spontaneous hyperadrenocorticism [41.3%, n = 19/46], chronic treatment with glucocorticoids [10.8%, n = 5/46], and hypothyroidism [15.2%, n = 7/46]). After 30 days, serum TG concentration normalized (<150 mg/dL) in 42 dogs (91.3%) and CHO concentration normalized (<270 mg/dL) in 22 of 33 dogs (66.7%). There was no difference in baseline TG concentration between the primary and secondary hyperlipidemia subgroups, but the decrease in TG concentration after treatment was greater in the primary hyperlipidemia subgroup. No adverse effects were observed, but ALT activity decreased significantly after 30 days of treatment.

CONCLUSIONS AND CLINICAL IMPORTANCE

Over 30 days, BZF was safe and effective in treatment of primary and secondary hyperlipidemia in dogs.

Clinical Relationship between Cholestatic Disease and Pituitary-Dependent Hyperadrenocorticism in Dogs: A Retrospective Case Series

Background

A high prevalence of cholestatic disease, including gallbladder mucocele (GBM), has been reported in dogs with naturally occurring pituitary‐dependent hyperadrenocorticism (PDH).

Hypothesis/Objectives

Differences exist in the clinical features of dogs with PDH and concurrent cholestatic disease, and also is the management of these dogs with trilostane.

Animals

Sixty‐five client‐owned dogs with naturally occurring PDH.

Methods

This was a retrospective, observational case series. Each dog was treated with trilostane for at least 3 months before the study, and had a good clinical response, as determined by owners. Statistical comparisons of clinical signs, results of routine blood tests, basal and post‐ACTH cortisol concentration, and optimal trilostane dosage were made after dogs were separated into the following 3 groups by ultrasonographic imaging: normal on ultrasound (NOU) group, cholestasis group, and GBM group.

Results

The GBM group had more severe clinical signs and significantly different total serum cholesterol concentration and post‐ACTH stimulation cortisol concentration at the time of diagnosis. Dogs that weighed <6 kg had a significantly higher prevalence of cholestatic disease than did the other dogs (P = .003). The optimal trilostane dosages for the GBM and cholestasis groups were 2.5 and 1.5 times the dosage of the NOU group, respectively (P < .001).

Conclusions and Clinical Importance

Gallbladder disease associated with cholestatic disease is correlated with PDH in dogs, in both its clinical features and drug management. These findings may be associated with hypercholesterolemia, unidentified genetic factors, and the hydrophobic nature of trilostane.

In vitro fermentation characteristics, in vivo ileal and total tract nutrient digestibilities, and fecal microbiota responses of dogs to α-cyclodextrin

The objectives were to examine in vitro fermentation characteristics, in vivo nutrient digestibility, fecal microbiota, and serum lipid profiles as affected by α-cyclodextrin (ACD) supplementation. Short-chain fatty acid (SCFA) production was measured after in vitro fermentation for 3, 6, 9, and 12 h of ACD, β-cyclodextrin, and γ-cyclodextrin. Five mixed-breed hounds were used in a Latin square design. Each experimental period comprised 14 d, including 10 d for diet adaptation and 4 d for fecal collection. Dogs were fed, twice a day, an extruded diet made with poultry byproduct meal and brewer's rice as the main ingredients. Dogs were supplemented with 0, 1, 2, 3, or 4 g of ACD diluted in 15 mL of water twice daily for a total of 0, 2, 4, 6, and 8 g ACD/d. Maximal in vitro production of total SCFA was lowest for ACD. However, the greatest maximal production of propionate was noted for ACD treatment. Total tract nutrient digestibility and fecal DM concentration linearly decreased ( < 0.05) for treatment groups receiving ACD; no changes were observed for ileal digestibility. Serum cholesterol and triglyceride concentrations were within normal ranges for dogs and were not different among treatments. Similarly, no changes in fecal microbiota were observed. Overall, ACD supplementation appears to have no effect on nutrient absorption in the small intestine but may alter fermentation in the large bowel, which could lead to a higher proportion of propionate production as observed in the in vitro experiment.

Preliminary Analysis of Modified Low-Density Lipoproteins in the Serum of Healthy and Obese Dogs and Cats

Oxidized low-density lipoprotein (LDL) is thought to play an important role in the inflammatory response associated with human obesity. The purpose of this preliminary study was to determine oxidized LDL concentrations in healthy dogs and cats, and to evaluate whether obesity affects oxidized LDL concentration, using 39 cats and 19 dogs that had visited two different veterinary clinics in Japan. We hypothesized that oxidized LDL concentrations measured against body condition score (BCS) may have a potential value in evaluating the qualities of accumulated or circulating lipids in obese dogs and cats that do not show signs of metabolic diseases. The mean oxidized LDL value in BCS3 dogs (2.4 ± 0.9 μg/dl) was very similar to that of BCS5 dogs (2.2 ± 0.3 μg/dl). The mean oxidized LDL value of BCS4 dogs was 7.2 ± 10.3 μg/dl and the highest among three groups. BCS4 dogs included two dogs whose oxidized LDL values were higher than the mean oxidized LDL value of healthy humans (11.2 ± 0.3 μg/dl). On the other hand, the mean oxidized LDL value of BCS3 cats was 2.5 ± 0.9 μg/dl, and those of BCS4 and 5 cats were higher than that of BCS3, but there was no significant difference. The BCS4 cat group included one cat with a higher oxidized LDL value, and the BCS5 group also included two cats with oxidized LDL values higher than the mean oxidized LDL value of healthy humans. Interestingly, the oxidized LDL values in two obese dogs and three obese cats were indeed higher than the mean oxidized LDL value of humans with coronary artery disease (20.1 ± 1.1 μg/dl). In conclusion, this preliminary study showed reference ranges of oxidized dogs and cats against BCS. Obesity alone does not appear to have any direct effect on serum oxidized LDL values in healthy dogs and cats.

Pancreatitis in dogs and cats: definitions and pathophysiology

Pancreatitis, or inflammation of the pancreas, is commonly seen in dogs and cats and presents a spectrum of disease severities from acute to chronic and mild to severe. It is usually sterile, but the causes and pathophysiology remain poorly understood. The acute end of the disease spectrum is associated with a high mortality but the potential for complete recovery of organ structure and function if the animal survives. At the other end of the spectrum, chronic pancreatitis in either species can cause refractory pain and reduce quality of life. It may also result in progressive exocrine and endocrine functional impairment. There is confusion in the veterinary literature about definitions of acute and chronic pancreatitis and there are very few studies on the pathophysiology of naturally occurring pancreatitis in dogs and cats. This article reviews histological and clinical definitions and current understanding of the pathophysiology and causes in small animals by comparison with the much more extensive literature in humans, and suggests many areas that need further study in dogs and cats.

Evaluation of total dietary fiber concentration and composition of commercial diets used for management of diabetes mellitus, obesity, and dietary fat-responsive disease in dogs

OBJECTIVE

To determine total dietary fiber (TDF) concentration and composition of commercial diets used for management of obesity, diabetes mellitus, and dietary fat-responsive disease in dogs.

DESIGN

Cross-sectional study.

SAMPLE

Dry (n = 11) and canned (8) canine therapeutic diets.

PROCEDURES

Insoluble and soluble dietary fiber (IDF and SDF), high-molecular-weight SDF (HMWSDF), and low-molecular-weight SDF (LMWSDF) concentrations were determined. Variables were compared among diets categorized by product guide indication, formulation (dry vs canned), and regulatory criteria for light and low-fat diets.

RESULTS

SDF (HMWSDF and LMWSDF) comprised a median of 30.4% (range, 9.4% to 53.7%) of TDF; LMWSDF contributed a median of 11.5% (range, 2.7% to 33.8%) of TDF. Diets for diabetes management had higher concentrations of IDF and TDF with lower proportions of SDF and LMWSDF contributing to TDF, compared with diets for treatment of fat-responsive disease. Fiber concentrations varied within diet categories and between canned and dry versions of the same diet (same name and manufacturer) for all pairs evaluated. Diets classified as light contained higher TDF and IDF concentrations than did non-light diets. All canned diets were classified as low fat, despite providing up to 38% of calories as fat.

CONCLUSIONS AND CLINICAL RELEVANCE

Diets provided a range of TDF concentrations and compositions; veterinarians should request TDF data from manufacturers, if not otherwise available. Consistent responses to dry and canned versions of the same diet cannot necessarily be expected, and diets with the same indications may not perform similarly. Many diets may not provide adequate fat restriction for treatment of dietary fat-responsive disease.

Regulation effect of Aspirin Eugenol Ester on blood lipids in Wistar rats with hyperlipidemia

Background

Aspirin eugenol ester (AEE) is a promising drug candidate for treatment of inflammation, pain and fever and prevention of cardiovascular diseases with less side effects. The experiment will be conducted to investigate the efficacy of AEE on curing hyperlipidemia in Wistar rats. The rats were fed with high fat diet (HFD) for 8 weeks to induce hyperlipidemia.

Results

Compared with the model group, the results showed that AEE at 54 mg/kg dosage could significantly decrease the hyperlipidemia indexes including triglyceride (TG), low density lipoprotein (LDL) and total cholesterol (TCH) (p < 0.01), increase high density lipoprotein (HDL) (p < 0.05) for five weeks drug administration. Meanwhile, simvastatin had same effect on hyperlipidemia indexes such as TG, LDL, TC, but no significant increase in HDL.

Conclusion

AEE was effective against hyperlipidemia and had better anti-hyperlipidemic effect than its component, acetylsalicylic acid (Aspirin, ASA), eugenol and integration of ASA and eugenol. Under the experimental circumstance, the optimal dose of AEE to cure hyperlipidemia is 54 mg/kg for five weeks in Wistar rats.

Lipoprotein cholesterol and triglyceride concentrations associated with dog body condition score; effect of recommended fasting duration on sample concentrations in Japanese private clinics

The objectives of this study were to survey clinics’ guidance about recommended fasting duration (FD) prior to lipoprotein analysis, and to characterize lipoprotein cholesterol and triglyceride concentrations in obese and overweight dogs categorized on the basis of the 5-point body condition score (BCS) scale. A dataset was created from lipoprotein analysis medical records of 1,538 dogs from 75 breeds in 354 clinics from 2012 to 2013. A phone survey was conducted to obtain the clinics’ FD. Two-level linear mixed-effects models were applied to the data. Over 50% of the clinics said they recommended fasting for 12 hr or more. Dogs in clinics with FD 12 hr or more had lower chylomicron triglyceride concentrations than those in clinics with FD less than 8 hr (P=0.05). Mean (± SEM) BCS at sampling was 3.7 ± 0.02. Obese and overweight dogs had higher very low density lipoprotein (VLDL) and high density lipoprotein (HDL) cholesterol and triglyceride concentrations than ideal dogs (P<0.05), but no such difference was found for low density lipoprotein cholesterol and triglyceride concentrations (P≥0.07). Across all BCS, as dog age rose from 0 to 8 years old, HDL cholesterol concentrations decreased by 13.5 mg/dl, whereas VLDL triglyceride concentrations increased by 81.7 mg/dl (P<0.05). In conclusion, FD of 8 hr or less may affect lipoprotein lipid concentrations. Obese and overweight dogs were characterized as having high VLDL and HDL cholesterol and triglyceride concentrations.

Extraction of a soluble polysaccharide from Auricularia polytricha and evaluation of its anti-hypercholesterolemic effect in rats

Mushroom extracts are a new source of supplements for health and pharmaceutical due to their bioactivities. This study was to optimize the extraction parameters of a soluble polysaccharide from Auricularia polytricha (SPAP) by response surface methodology. The practical optimum parameters were an extraction time of 4h, an extraction temperature of 95 °C and a ratio of water to fruiting bodies of 28 mL/g, and the highest extraction rate was 19.77%. In vivo, male Sprague-Dawley (SD) rats were diet-induced hypercholesterolemic models and oral administration of SPAP to evaluate anti-hypercholesterolemic effects. The results showed that SPAP decreased the serum concentrations of blood lipid, made them close to the normal level. The total cholesterol in the SPAP consumption groups was significantly decreased 34.6 ± 7.6% and 33.3 ± 7.9% with dose of 4.5 and 9.0mg/kg BW in the 29th day. This study suggested that SPAP was a suitable natural agent and may be applied in therapy.

Comparison of plasma lipoprotein profiles and malondialdehyde between hyperlipidemia dogs with/without treatment

Background

The aim of this study is to compare metabolic parameters, malondialdehyde as a lipid oxidation marker, and lipid profiles between dogs with untreated hyperlipidemia and hyperlipidemia with treatment, in order to examine the usefulness of malondialdehyde and lipid profiles as diagnostic parameters at early stages of hyperlipidemia.

Results

Dog samples were collected from four different veterinary clinics across Japan from March to June 2013. They were separated into three groups: control, untreated hyperlipidemia based on temporally screening, and hyperlipidemia with current anti-hyperlipidemic (statins and fibrates) treatment. Triglyceride levels of untreated hyperlipidemia dogs were significantly higher than those of control dogs. ALT levels of hyperlipidemic dogs with treatment were the highest among three groups. VLDL and LDL of both cholesterol and triglyceride of untreated hyperlipidemia dogs were the highest among three groups. HDL₁ levels in triglyceride of hyperlipidemia dogs with treatment were significantly higher than those of control and untreated hyperlipidemia dog. Malondialdehyde concentrations of untreated hyperlipidemia dogs were significantly higher than those of control and hyperlipidemic dogs with treatment.

Conclusions

In this study, dogs with untreated hyperlipidemia clearly showed abnormal lipid status, whereas hyperlipidemic dogs under anti-hyperlipidemia treatment showed more normal lipid status suggesting the effectiveness of the therapy. Anti-hyperlipidemics (statins and fibrates) for dogs are also effective in relieving elevated levels of lipids and lipid oxidation. Plasma lipid (triglyceride and cholesterol) profiles and malondialdehyde are useful diagnostic tools for identifying early stages of untreatment hyperlipidemia in dogs.

The use of the rapid osmotic fragility test as an additional test to diagnose canine immune-mediated haemolytic anaemia

Background

Diagnosing canine immune-mediated haemolytic anaemia (IMHA) is often challenging because all currently available tests have their limitations. Dogs with IMHA often have an increased erythrocyte osmotic fragility (OF), a characteristic that is sometimes used in the diagnosis of IMHA. Since the classic osmotic fragility test (COFT) is time-consuming and requires specialized equipment, an easy and less labour-intensive rapid osmotic fragility test (ROFT) has been used in some countries, but its diagnostic value has not yet been investigated.

This study aimed to evaluate erythrocyte osmotic fragility in dogs with and without IMHA, to compare results of the classic (COFT) and rapid (ROFT) test and to assess the value of the ROFT as diagnostic test for canine IMHA.

Nineteen dogs with IMHA (group 1a), 21 anaemic dogs without IMHA (group 1b), 8 dogs with microcytosis (group 2), 13 hyperlipemic dogs (group 3), 10 dogs with lymphoma (group 4), 8 dogs with an infection (group 5) and 13 healthy dogs (group 6) were included.

In all dogs, blood smear examination, in-saline auto-agglutination test, Coombs’ test, COFT and ROFT were performed. In the COFT, OF5, OF50 and OF90 were defined as the NaCl concentrations at which respectively 5, 50 and 90% of erythrocytes were haemolysed.

Results

Compared with healthy dogs, OF5 and OF50 were significantly higher in group 1a (P < 0.001) and OF5 was significantly higher in group 3 (P = 0.0266). The ROFT was positive in 17 dogs with IMHA, 10 hyperlipemic dogs, one anaemic dog without IMHA and one healthy dog.

Conclusions

Osmotic fragility was increased in the majority of dogs with IMHA and in dogs with hyperlipidemia, but not in dogs with microcytosis, lymphoma or an infection. Although more detailed information was obtained about the osmotic fragility by using the COFT, the COFT and ROFT gave similar results. The ROFT does not require specialized equipment, is rapid and easy to perform and can be used easily in daily practice. Although, the ROFT cannot replace other diagnostic tests, it may be a valuable additional tool to diagnose canine IMHA.

Dog age and breeds associated with high plasma cholesterol and triglyceride concentrations

The objectives of this study were to set specific dog breed and sex standards for total cholesterol (T-Cho) and total triglyceride (T-TG) concentrations in dogs and to quantify the associations between dog age and concentrations of both lipids for different breeds. Increased age was associated with higher T-Cho and T-TG concentrations in all five breed groups (P<0.05); T-Cho concentrations increased by 62.5 mg/dl between 9 and 16 years of age, and T-TG concentrations increased by 4.8 mg/dl per year of age (P<0.05). Miniature Schnauzers had the highest T-Cho concentrations of the studied breeds, while Miniature Dachshunds had the lowest concentrations (P<0.05). Veterinarians should consider dog age and breed when they use the lipid concentrations for diagnostic purposes.

Comparison of postprandial lipaemia between native and palm random esterified acid oils in two different monogastric species (dogs and broiler chickens)

It has been reported that applying a chemical reesterification process to a native fat results in a new fat source with different physicochemical properties due to their different fatty acid (FA) positional distribution within the glycerol moiety and their different proportions of mono (MAG)-, di (DAG)- and triacylglycerides (TAG). Thus, this reesterification could affect fat digestion, absorption and metabolism; and this effect could vary among species given their differences in fat metabolism. The aim of this study was to compare the effect of feeding two different random esterified acid oils (REAO), presenting different MAG, DAG and TAG proportions, with their corresponding native oil on postprandial lipaemia in broiler chickens and dogs. For this purpose, 18 dogs and 54 broiler chickens were fed a basal diet supplemented with palm native oil, palm REAO low MAG or palm REAO high MAG. The inclusion level of the oils was 10% of the diet in dogs and 6% in broiler chickens. Serum postprandial TAG concentration (mg/dl) after feeding a single meal was measured at different time points during 12 h in dogs and 3 h in chickens. Although fasting serum TAG concentration values were similar for both species (47 ± 2.4 mg/dl for dogs and 44 ± 3.0 mg/dl for broilers; p = 0.522), postprandial TAG concentrations tended to be higher in broilers than in dogs (p = 0.058). Treatment had no effect on TAG concentration at any time point in any species (p = 0.768 for dogs, p = 0.947 for broilers). However, the postprandial TAG curves were very different between species; in broiler chickens, TAG concentration returned to the fasting values 3 h after feeding while in dogs, the TAG concentration still had not returned to basal levels 12 h after feeding.

Novel lipoprotein density profiling in healthy dogs of various breeds, healthy Miniature Schnauzers, and Miniature Schnauzers with hyperlipidemia

BACKGROUND

Despite the importance of abnormalities in lipoprotein metabolism in clinical canine medicine, the fact that most previously used methods for lipoprotein profiling are rather laborious and time-consuming has been a major obstacle to the wide clinical application and use of lipoprotein profiling in this species. The aim of the present study was to assess the feasibility of a continuous lipoprotein density profile (CLPDP) generated within a bismuth sodium ethylenediaminetetraacetic acid (NaBiEDTA) density gradient to characterize and compare the lipoprotein profiles of healthy dogs of various breeds, healthy Miniature Schnauzers, and Miniature Schnauzers with primary hypertriacylglycerolemia. A total of 35 healthy dogs of various breeds with serum triacylglycerol (TAG) and cholesterol concentrations within their respective reference intervals were selected for use as a reference population. Thirty-one Miniature Schnauzers with serum TAG and cholesterol concentrations within their respective reference intervals and 31 Miniature Schnauzers with hypertriacylglyceridemia were also included in the study.

RESULTS

The results suggest that CLPDP using NaBiEDTA provides unique diagnostic information in addition to measurements of serum TAG and cholesterol concentrations and that it is a useful screening method for dogs with suspected lipoprotein metabolism disorders. Using the detailed and continuous density distribution information provided by the CLPDP, important differences in lipoprotein profiles can be detected even among dogs that have serum TAG and cholesterol concentrations within the reference interval. Miniature Schnauzers with serum TAG and cholesterol concentrations within the reference interval had significantly different lipoprotein profiles than dogs of various other breeds. In addition, it was further established that specific lipoprotein fractions are associated with hypertriacylglyceridemia in Miniature Schnauzers.

CONCLUSIONS

The results of the present study suggest that density gradient ultracentrifugation using NaBiEDTA is a useful screening method for the study of lipoprotein profiles in dogs. Therefore, this method could potentially be used for diagnostic purposes for the separation of dogs suspected of having lipoprotein abnormalities from healthy dogs.

Potential adverse effects of omega-3 Fatty acids in dogs and cats

Fish oil omega-3 fatty acids, mainly eicosapentaenoic acid and docosahexaenoic acid, are used in the management of several diseases in companion animal medicine, many of which are inflammatory in nature. This review describes metabolic differences among omega-3 fatty acids and outlines potential adverse effects that may occur with their supplementation in dogs and cats with a special focus on omega-3 fatty acids from fish oil. Important potential adverse effects of omega-3 fatty acid supplementation include altered platelet function, gastrointestinal adverse effects, detrimental effects on wound healing, lipid peroxidation, potential for nutrient excess and toxin exposure, weight gain, altered immune function, effects on glycemic control and insulin sensitivity, and nutrient-drug interactions.

Avaliação de colesterol e triglicerídeos séricos em cães saudáveis suplementados com ômega n-3

A análise da concentração sérica de colesterol e triglicerídeos foi realizada em 20 cães, sem raça definida, saudáveis, 10 machos e 10 fêmeas, previamente e após a suplementação por 30 dias com ácidos graxos poli-insaturados de cadeia longa derivados do ômega n-3 (497mg ácido docosa-hexaenoico e 780mg ácido eicosapentanoico). A concentração sérica de colesterol apresentou redução significativa após a suplementação em ambos os sexos (271,6±79,8mg/dL; 236,2±67,6mg/dL, antes e após suplementação, respectivamente). Em relação à concentração sérica de triglicerídeos, houve redução apenas nas fêmeas (57,8±12,1mg/dL; 45,2±7,8mg/dL, antes e após suplementação, respectivamente), não havendo efeito da suplementação nos machos.

Chronic pancreatitis in dogs: a retrospective study of clinical, clinicopathological, and histopathological findings in 61 cases

The objective of this study was to characterize the clinical, clinicopathological, and histopathological findings of dogs with chronic pancreatitis. The necropsy database at Texas A&M University was searched for reports of dogs with histological evidence of chronic pancreatitis defined as irreversible histologic changes of the pancreas (i.e. fibrosis or atrophy). A reference necropsy population of 100 randomly selected dogs was used for signalment and concurrent disease comparisons. Cases were categorized as clinical or incidental chronic pancreatitis based on the presence of vomiting, decreased appetite, or both vs. neither of these signs. All archived pancreas samples were scored histologically using a published scoring system. Sixty-one dogs with chronic pancreatitis were included. The most frequent clinical signs were lethargy, decreased appetite, vomiting, and diarrhea. Compared to the reference necropsy population, chronic pancreatitis cases were more likely to be older, neutered, of the non-sporting/toy breed group, and to have concurrent endocrine, hepatobiliary, or neurological disease. Clinical cases had significantly higher histological scores for pancreatic necrosis and peripancreatic fat necrosis, and were significantly more likely to have hepatobiliary or endocrine disease as well as increased liver enzyme activities, or elevated cholesterol and bilirubin concentrations. In conclusion, clinical disease resulting from chronic pancreatitis might be related to the presence of pancreatic necrosis and pancreatic fat necrosis. The signalment, presentation, and concurrent diseases of dogs with chronic pancreatitis are similar to those previously reported for dogs with acute pancreatitis.

Characterization of a canine model of glycogen storage disease type IIIa

Glycogen storage disease type IIIa (GSD IIIa) is an autosomal recessive disease caused by deficiency of glycogen debranching enzyme (GDE) in liver and muscle. The disorder is clinically heterogeneous and progressive, and there is no effective treatment. Previously, a naturally occurring dog model for this condition was identified in curly-coated retrievers (CCR). The affected dogs carry a frame-shift mutation in the GDE gene and have no detectable GDE activity in liver and muscle. We characterized in detail the disease expression and progression in eight dogs from age 2 to 16 months. Monthly blood biochemistry revealed elevated and gradually increasing serum alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) activities; serum creatine phosphokinase (CPK) activity exceeded normal range after 12 months. Analysis of tissue biopsy specimens at 4, 12 and 16 months revealed abnormally high glycogen contents in liver and muscle of all dogs. Fasting liver glycogen content increased from 4 months to 12 months, but dropped at 16 months possibly caused by extended fibrosis; muscle glycogen content continually increased with age. Light microscopy revealed significant glycogen accumulation in hepatocytes at all ages. Liver histology showed progressive, age-related fibrosis. In muscle, scattered cytoplasmic glycogen deposits were present in most cells at 4 months, but large, lake-like accumulation developed by 12 and 16 months. Disruption of the contractile apparatus and fraying of myofibrils was observed in muscle at 12 and 16 months by electron microscopy. In conclusion, the CCR dogs are an accurate model of GSD IIIa that will improve our understanding of the disease progression and allow opportunities to investigate treatment interventions.

Pathophysiology of acute pancreatitis: potential application from experimental models and human medicine to dogs

The cellular events leading to pancreatitis have been studied extensively in experimental models. Understanding the cellular events and inciting causes of the multisystem inflammatory cascades that are activated with this disease is of vital importance to advance diagnosis and treatment of this condition. Unfortunately, the pathophysiology of pancreatitis in dogs is not well understood, and extrapolation from experimental and human medicine is necessary. The interplay of the inflammatory cascades (kinin, complement, cytokine) is extremely complex in both initiating leukocyte migration and perpetuating disease. Recently, nitric oxide (NO) and altered microcirculation of the pancreas have been proposed as major initiators of inflammation. In addition, the role of the gut is becoming increasingly explored as a cause of oxidative stress and potentiation of systemic inflammation in pancreatitis.

Use of a meal challenge test to estimate peak postprandial triglyceride concentrations in dogs

OBJECTIVE

To develop a standardized meal challenge test by assessing associations between food-withheld preprandial (ie, fasting) and postprandial triglyceride concentrations, determining the most appropriate sampling time to detect the peak concentration (highest postprandial concentration), and estimating reference intervals for fasting and postprandial concentrations in healthy dogs.

ANIMALS

12 lean healthy mixed-breed dogs.

PROCEDURES

Dogs were fed a dry commercially available diet (fat, 31% metabolizable energy) for 3 weeks. After food was withheld for 23 to 24 hours, plasma triglyceride concentrations were measured 1 and 0.083 hours before and 1, 2, 3, 4, 5, 6, 9, and 12 hours after feeding of a standardized challenge meal (median amount eaten, 63 kcal/kg [127 kcal/kg⁰.⁷⁵]). Correlation and agreement between concentrations at peak and other time points were assessed by use of correlation coefficients and Bland-Altman limits of agreement. Reference intervals were calculated by use of a robust method.

RESULTS

Fasting and peak triglyceride concentrations were not closely associated. The highest concentration among samples obtained 2, 5, and 6 hours after meal consumption had closest agreement with peak concentration. In 5 of 12 dogs, concentrations 12 hours after eating were still significantly above baseline concentration (mean of each dog's fasting concentrations).

CONCLUSIONS AND CLINICAL RELEVANCE

Fasting triglyceride concentration could not be used to accurately predict peak concentration. When estimating peak concentration, multiple samples should be collected 2, 5, and 6 hours after consumption of a standardized meal. Food may need to be withheld for > 12 hours when assessing fasting concentrations in healthy dogs.