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.

Sequence Analysis of Six Candidate Genes in Miniature Schnauzers with Primary Hypertriglyceridemia.

Miniature Schnauzers are predisposed to primary hypertriglyceridemia (HTG). In this study, we performed whole genome sequencing (WGS) of eight Miniature Schnauzers with primary HTG and screened for risk variants in six HTG candidate genes: LPL, APOC2, APOA5, GPIHBP1, LMF1, and APOE. Variants were filtered to identify those present in ≥2 Miniature Schnauzers with primary HTG and uncommon (<10% allele frequency) in a WGS variant database including 613 dogs from 61 other breeds. Three variants passed filtering: an APOE TATA box deletion, an LMF1 intronic SNP, and a GPIHBP1 missense variant. The APOE and GPIHBP1 variants were genotyped in a cohort of 108 Miniature Schnauzers, including 68 with primary HTG and 40 controls. A multivariable regression model, including age and sex, did not identify an effect of APOE (estimate = 0.18, std. error = 0.14; p = 0.20) or GPIHBP1 genotypes (estimate = -0.26, std. error = 0.42; p = 0.54) on triglyceride concentration. In conclusion, we did not identify a monogenic cause for primary HTG in Miniature Schnauzers in the six genes evaluated. However, if HTG in Miniature Schnauzers is a complex disease resulting from the cumulative effects of multiple variants and environment, the identified variants cannot be ruled out as contributing factors.

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.

Effects of antimicrobials on the gastrointestinal microbiota of dogs and cats.

Among several environmental factors, exposure to antimicrobials has been in the spotlight as a cause of profound and long-term disturbance of the intestinal microbiota. Antimicrobial-induced dysbiosis is a general term and includes decreases in microbial richness and diversity, loss of beneficial bacterial groups, blooms of intestinal pathogens and alterations in the metabolic functions and end-products of the microbiota. Mounting evidence from human and experimental animal studies suggest an association between antimicrobial-induced dysbiosis and susceptibility to gastrointestinal, metabolic, endocrine, immune and neuropsychiatric diseases. These associations are commonly stronger after early life exposure to antimicrobials, a period during which maturation of the microbiota and immune system take place in parallel. In addition, these associations commonly become stronger as the number of antimicrobial courses increases. The repeatability of these findings among different studies as well as the presence of a dose-dependent relationship between antimicrobial exposure and disease development collectively require careful consideration of the need for antimicrobial use. There are limited studies are available in dogs and cats regarding the long-term effects of antimicrobials on the microbiota and subsequent susceptibility to diseases. This review discusses the effects of antimicrobials on the gastrointestinal microbiota and the most important associations between antimicrobial-induced dysbiosis and diseases in humans, dogs, and cats.

Serum α1-Proteinase Inhibitor, Calprotectin, and S100A12 Concentrations in the Characterization of Pancreatitis in Dogs.

Miniature Schnauzers are predisposed to develop pancreatitis, with familial hypertriglyceridemia (HTG) described as a potential risk factor. Diagnosing pancreatitis in dogs is based on the integration of serum canine-specific pancreatic lipase (cPLI) concentration, clinical presentation, and diagnostic imaging findings. However, markers of systemic inflammation and antiprotease activity have not been extensively investigated in the characterization and prognostication of pancreatitis in dogs. Serum concentrations of alpha1-proteinase inhibitor (α1PI; as a marker of systemic antiprotease response) and calprotectin and S100A12 (as markers of systemic inflammation) were measured in serum samples from 35 Miniature Schnauzers diagnosed with pancreatitis (serum cPLI concentration >400 µg/L, clinical signs, abdominal imaging findings). These markers were evaluated for possible associations with patient characteristics, clinical presentation, risk factors for pancreatitis, and outcome. The study showed that biomarkers of systemic inflammation and antiprotease activity are commonly increased in Miniature Schnauzers with pancreatitis. Whereas serum calprotectin and S100A12 concentrations were found to have limited utility in differentiating pancreatitis presentations, serum α1PI concentrations and potentially also the serum calprotectin-to-S100A12 ratio might be non-invasive surrogate markers of disease severity in dogs with pancreatitis.

Seroprevalence of and Risk Factors for Toxoplasma gondii Infection in Cats from Greece.

Toxoplasmosis is one of the most important protozoan diseases with a global impact on the health of domestic cats and with zoonotic significance. The aims of this study were to determine the prevalence of seropositivity for Toxoplasma gondii in different populations of cats in Greece and to assess risk factors for seropositivity. A total of 457 cats were prospectively enrolled, and a commercially available indirect immunofluorescence antibody testing (IFAT) kit was used for the detection of anti-T. gondii immunoglobulin G (IgG) in serum. Overall, 95 (20.8%) of the 457 cats were seropositive for T. gondii. Based on multivariate analysis, factors associated with seropositivity included older age [Odds ratio (OR), 1.33; p < 0.001]; a history of cat-fight trauma (OR, 3.88; p = 0.004); and lack of vaccination against calicivirus, herpesvirus-1, panleukopenia, and rabies (OR, 10; p = 0.002). This study shows a high prevalence of seropositivity for T. gondii in cats in Greece. This implies that toxoplasmosis is still a major public health concern and that optimal strategies for the prevention of infection with T. gondii in cats should be established.

Seroprevalence of and risk factors for feline coronavirus infection in cats from Greece.

Feline coronavirus (FCoV) is a highly contagious and ubiquitous virus of domestic cats and wild felids. Feline infectious peritonitis (FIP) is a fatal, systemic disease caused by FCoV infection when spontaneous mutations of the viral genome take place. The aims of this study were primarily to determine the prevalence of seropositivity for FCoV in different populations of cats in Greece and assess risk factors for seropositivity. A total of 453 cats were prospectively enrolled in the study. A commercially available IFAT kit was used for the detection of FCoV IgG antibodies in serum. Overall, 55 (12.1 %) of the 453 cats were seropositive for FCoV. Based on multivariable analysis, factors associated with FCoV-seropositivity included cats adopted as strays and contact with other cats. This is the first extensive study on the epidemiology of FCoV in cats from Greece and one of the largest worldwide. Feline coronavirus infection is relatively common in Greece. Therefore, it is necessary to establish optimal strategies for the prevention of FCoV infection, considering the high-risk groups of cats identified in this study.

Specificity of a pancreatic lipase point-of-care test and agreement with pancreatic lipase immunoreactivity in cats without clinical evidence of pancreatitis.

OBJECTIVES: The aim of this study was to determine the specificity of a rapid point-of-care test for the estimation of feline pancreatic lipase (SNAP fPL) in healthy and sick cats without clinical evidence of pancreatitis. A second objective was to evaluate the agreement between SNAP fPL and serum pancreatic lipase immunoreactivity (fPLI), as measured by Spec fPL. METHODS: A total of 150 cats were prospectively enrolled into this study. Of them, 82 cats were healthy while 68 cats had various diseases but no clinical signs (eg, anorexia, depression, vomiting) raising a suspicion of pancreatitis. RESULTS: SNAP fPL was normal in 133/150 cats (specificity 89%) without obvious clinical pancreatitis. SNAP fPL was normal in 74/82 healthy cats (specificity 90%) and in 59/68 cats that were sick but without typical signs of pancreatitis (specificity 87%). The agreement between SNAP fPL and Spec fPL was substantial (k = 0.64) in healthy cats and almost perfect (k = 0.93) in sick cats. The overall agreement between SNAP fPL and Spec fPL was almost perfect (k = 0.81). CONCLUSIONS AND RELEVANCE: The specificity of SNAP fPL in this group of cats was high. There was a substantial and almost perfect agreement between the SNAP fPL and Spec fPL in healthy cats and sick cats without suspected pancreatitis, respectively. In the small percentage of cats with abnormal SNAP fPL and/or Spec fPL results, the possibility of subclinical pancreatitis cannot be excluded.

Fecal Calprotectin Concentrations in Cats with Chronic Enteropathies.

Diagnosis of feline chronic inflammatory enteropathies (CIE) and the differentiation from small cell intestinal lymphoma (SCL) can be challenging. Intestinally expressed calprotectin (S100A8/A9 protein complex) appears to be part of the complex pathogenesis of feline chronic enteropathies (FCE). Fecal calprotectin is a non-invasive biomarker for intestinal inflammation in humans and dogs but has not yet been evaluated in cats. We hypothesized that fecal calprotectin (fCal) concentrations are increased in FCE, correlate with clinical and/or histologic disease severity, and distinguish cases of CIE from SCL. This case-control study included fecal samples and patient data from cats with CIE (n = 34), SCL (n = 17), other gastrointestinal (GI) diseases (n = 16), and cats with no clinical signs of GI disease (n = 32). fCal concentrations were measured using the immunoturbidimetric fCal turbo assay (Bühlmann Laboratories). Compared to healthy cats, fCal concentrations were significantly increased in CIE, SCL, and other diseases (all p < 0.0001), but were not different between these three groups (all p > 0.05), or between cats with extra-GI diseases and healthy controls. These findings suggest that fCal may have utility as a clinical biomarker for FCE but not for intestinal disease differentiation. It further supports the role of calprotectin in the pathogenesis of the spectrum of FCE, which includes CIE and SCL.

Fecal acute phase proteins in cats with chronic enteropathies.

BACKGROUND: Chronic enteropathies (CE) are common in cats and reliable biomarkers that can distinguish different causes and predict or monitor response to treatment are currently lacking. HYPOTHESIS: To evaluate certain acute phase proteins in feces that could potentially be used as biomarkers in cats with CE. ANIMALS: Twenty-eight cats with either inflammatory bowel disease (IBD; n = 13), food-responsive enteropathy (FRE; n = 3) or small cell gastrointestinal lymphoma (SCGL; n = 12) and 29 healthy control cats were prospectively enrolled. METHODS: Fecal concentrations of haptoglobin, alpha-1-acid-glycoprotein (AGP), pancreatitis-associated protein-1 (PAP-1), ceruloplasmin, and C-reactive protein (CRP) were measured using Spatial Proximity Analyte Reagent Capture Luminescence (SPARCL) immunoassays before and after initiation of treatment. Cats were treated with diet and/or prednisolone (IBD cats), plus chlorambucil (SCGL cats). RESULTS: Compared with controls, median fecal AGP concentrations were significantly lower (25.1 vs 1.8 µg/g; P = .003) and median fecal haptoglobin (0.17 vs 0.5 µg/g), PAP-1 (0.04 vs 0.4 µg/g) and ceruloplasmin (0.15 vs 4.2 µg/g) concentrations were significantly higher (P < .001) in cats with CE. Median fecal AGP concentrations were significantly lower (P = .01) in cats with IBD and FRE (0.6 µg/g) compared with cats with SCGL (10.75 µg/g). A significant reduction was found in CE cats after treatment for median fecal ceruloplasmin concentrations (6.36 vs 1.16 µg/g; P = .04). CONCLUSIONS: Fecal AGP concentration shows promise to differentiate cats with SCGL from cats with IBD and FRE. Fecal ceruloplasmin concentrations may be useful to objectively monitor response to treatment in cats with CE.

Feline Comorbidities: Clinical perspective on diabetes mellitus and pancreatitis.

PRACTICAL RELEVANCE: Diabetes mellitus (DM) is one of the most common feline endocrine disorders. It has been shown by several studies that DM in cats frequently coexists with pancreatitis. CLINICAL CHALLENGES: It has not been definitively established what the exact pathogenetic association between DM and pancreatitis is in the cat. However, the association between these two conditions is most likely bidirectional, with DM predisposing cats to pancreatitis and vice versa. Diagnosis of pancreatitis in cats with DM is crucial because concurrent pancreatitis commonly leads to difficulties in the management of DM. When pancreatitis is associated with diabetic ketoacidosis (DKA), therapeutic management is even more challenging. AIMS: This review focuses on the concurrent presence of DM or DKA and pancreatitis in cats, mainly focusing on their clinical management. EVIDENCE BASE: Information provided in this review is based on feline-specific clinical research when available. In addition, comparative and human research, as well as clinical experience, has been used to enrich knowledge in areas where feline-specific research is not yet available.

Associations among serum insulin, calprotectin, and C-reactive protein concentrations in Miniature Schnauzers with idiopathic hyperlipidemia before and after feeding an ultra-low-fat diet.

BACKGROUND: Miniature Schnauzers (MS) commonly have idiopathic hypertriglyceridemia (HTGL), which is associated with insulin resistance (IR) and a subclinical inflammatory phenotype. OBJECTIVES: Determine the association between indicators of IR and inflammatory biomarkers in MS with and without HTGL and identify how indicators of IR are affected by dietary intervention in MS with HTGL. ANIMALS: Seventy MS with HTGL and 79 MS without HTGL. In addition, 15 MS with HTGL were placed on a low-fat diet. METHODS: Serum concentrations of triglycerides, cholesterol, calprotectin, insulin, and glucose were compared between groups. RESULTS: Serum glucose and calprotectin concentrations (shown to be higher in MS with HTGL than in MS without HTGL) were inversely correlated (ρ = -.28; P < .001). After dietary intervention, median serum insulin concentrations were 8.1 mU/L compared to 20.8 mU/L before dietary intervention (P = .06). Dogs with complete resolution of HTGL after dietary intervention (5 dogs) had significantly lower serum insulin concentrations compared to baseline (P = .03). CONCLUSION AND CLINICAL IMPORTANCE: The subclinical inflammatory phenotype in MS with HTGL appears to be associated with IR. Resolution of HTGL by dietary intervention is associated with a decrease in serum insulin concentrations. The implication of the increase in serum calprotectin concentrations after resolution of HTGL warrants further study.

Resting and postpradial serum cholecystokinin concentrations and evaluation of the effect of seeing and/or smelling food on serum cholecystokinin and bile acid concentrations in healthy dogs.

Serum bile acids concentrations rise postprandially. However, some dogs show paradoxical serum bile acids results with higher pre-prandial than post-prandial concentrations. The aim of this study was to evaluate serum cholecystokinin (CCK) concentrations and determine whether they correspond to paradoxical serum bile acids concentrations. In addition, seeing and smelling food was investigated as a possible cause for paradoxical serum bile acids results. Eight healthy dogs owned by volunteers enrolled in this experimental study. Food was withheld from the dogs for 12 h with great care not to expose them to any sight or smell of food. Blood samples were collected at 0, 30, 60, 120, 180, 240, 480 and 720 min after feeding. Food was then withheld again for 24 h, and blood samples were collected at 0, 30, 60, 120, 180, 240, 480 and 720 min after seeing and smelling food. After feeding, serum CCK concentrations increased, but paradoxical serum CCK concentrations were observed in some of dogs, but only one of those had also paradoxical serum bile acids concentrations. After seeing and smelling food, serum CCK and serum bile acids concentrations did not significantly increase. In conclusion, paradoxical serum CCK concentrations can occur in some healthy dogs after feeding. However, no correlation with paradoxical serum bile acids concentrations was found. Seeing or smelling food are unlikely causes for paradoxical serum bile acids concentrations. Additional studies are warranted to further evaluate the relationship of serum CCK and bile acids concentrations in healthy dogs and dogs with gastrointestinal disease.

The Serum and Fecal Metabolomic Profiles of Growing Kittens Treated with Amoxicillin/Clavulanic Acid or Doxycycline.

The long-term impact of antibiotics on the serum and fecal metabolome of kittens has not yet been investigated. Therefore, the objective of this study was to evaluate the serum and fecal metabolome of kittens with an upper respiratory tract infection (URTI) before, during, and after antibiotic treatment and compare it with that of healthy control cats. Thirty 2-month-old cats with a URTI were randomly assigned to receive either amoxicillin/clavulanic acid for 20 days or doxycycline for 28 days, and 15 cats of similar age were enrolled as controls. Fecal samples were collected on days 0, 20/28, 60, 120, and 300, while serum was collected on days 0, 20/28, and 300. Untargeted and targeted metabolomic analyses were performed on both serum and fecal samples. Seven metabolites differed significantly in antibiotic-treated cats compared to controls on day 20/28, with two differing on day 60, and two on day 120. Alterations in the pattern of serum amino acids, antioxidants, purines, and pyrimidines, as well as fecal bile acids, sterols, and fatty acids, were observed in antibiotic-treated groups that were not observed in control cats. However, the alterations caused by either amoxicillin/clavulanic acid or doxycycline of the fecal and serum metabolome were only temporary and were resolved by 10 months after their withdrawal.

Serial Measurement of Serum Pancreatic Lipase Immunoreactivity, Feline Trypsin-like Immunoreactivity, and Cobalamin Concentrations in Kittens.

Serum concentrations of feline pancreatic lipase immunoreactivity (fPLI), feline trypsin-like immunoreactivity (fTLI), and cobalamin are commonly used for the diagnostic investigation of cats with gastrointestinal signs. No information on these parameters in healthy cats less than 1 year of age exists. We aimed to evaluate serum concentrations of fPLI, fTLI, and cobalamin in healthy cats at different time-points during their first 12 months of life. Fourteen healthy 2-month-old kittens were included. Blood was collected at 2, 3, 4, 6, and 12 months of age, and serum concentrations of fPLI, fTLI, and cobalamin were measured. While there was a statistically significant difference in serum fPLI concentrations over time, there was no statistically significant difference between individual time-points. There was no significant difference in serum fTLI concentrations over time. Serum cobalamin concentrations were below the reference interval in 3/13 cats at 2 months of age and were significantly lower by 3 months, when 13/14 had hypocobalaminemia. By 12 months, serum cobalamin had significantly increased, yet 4/12 cats still had hypocobalaminemia. Serum fPLI and fTLI concentrations did not show any statistically or clinically significant differences in young kittens. In contrast, serum cobalamin concentrations were commonly below the reference interval in kittens. Serum fPLI and fTLI concentrations are not practically affected by age in kittens as young as 2 months of age and could be used for the investigation of pancreatic diseases.

Prevalence and Risk Factors for Bartonella spp. and Haemoplasma Infections in Cats from Greece.

Bartonellosis and haemoplasmosis are vector-borne diseases with global impact on the health of domestic cats and of zoonotic importance. The aim of this study was to describe the epidemiological aspects of various populations of cats infected with Bartonella spp. or haemoplasma species. The populations evaluated included client-owned cats, stray cats and cats that live in breeding catteries in Greece. A total of 452 cats were prospectively enrolled into the study. A commercially available indirect immunofluorescence antibody testkit was used for the detection of Bartonella henselae IgG antibodies in serum. PCRs for the detection of Bartonella spp. and haemoplasma species DNA in the blood were also performed in a subgroup of 242 of the 452 cats. Risk factors for B. henselae seropositivity and infection with the haemoplasma species were determined using multivariable analysis. Overall, 160 (35.4%) of the 452 cats were seropositive for B. henselae. Seven (2.9%) and 46 (19%) of the 242 cats were PCR-positive for Bartonella spp. and haemoplasma species, respectively. The factors associated with B. henselae seropositivity, based on multivariate analysis, included older age, outdoor access, living region and flea infestation. Non-administration of ectoparasiticides was associated with haemoplasma species infection. This study shows a high prevalence of seropositivity for B. henselae and a relatively high prevalence of infection with haemoplasma species. Therefore, it is necessary to establish optimal strategies for the prevention of Bartonella spp. and haemoplasma species infections, considering the high-risk groups of cats identified in this study.

Association of hypertriglyceridemia with insulin resistance in healthy Miniature Schnauzers.

OBJECTIVE: To determine whether hypertriglyceridemia in Miniature Schnauzers is associated with insulin resistance. DESIGN: Case-control study. ANIMALS: 28 Miniature Schnauzers with hypertriglyceridemia and 31 Miniature Schnauzers for which serum triglyceride concentrations were within the reference range (control dogs). PROCEDURES: All dogs had no history of chronic disease, were free of clinical signs for at least 3 months prior to blood collection, and were not receiving any medications known to affect lipid metabolism or serum insulin concentration. Food was withheld from each dog for ≥ 12 hours; a 5- to 10-mL blood sample was collected and allowed to clot to obtain serum. Serum insulin and glucose concentrations were measured, and the homeostasis model assessment (HOMA) score was calculated (ie, [basal serum insulin concentration {mU/L} × basal serum glucose concentration {mmol/L}]/22.5). RESULTS: Median serum insulin concentration was significantly higher in hypertriglyceridemic Miniature Schnauzers (21.3 mU/L) than it was in control dogs (12.5 mU/L). The percentage of dogs with high serum insulin concentrations was significantly greater in the hypertriglyceridemic group (28.6%) than it was in the control group (6.5%; odds ratio, 5.8; 95% confidence interval, 1.1 to 30.2). Median HOMA score for hypertriglyceridemic Miniature Schnauzers (4.9) was significantly higher than that for control dogs (2.8). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that hypertriglyceridemia in Miniature Schnauzers is often associated with insulin resistance. Further studies are needed to determine the prevalence and clinical importance of insulin resistance in hypertriglyceridemic Miniature Schnauzers.

Serum feline pancreatic lipase immunoreactivity and trypsin-like immunoreactivity concentrations in cats with experimentally induced chronic kidney disease.

BACKGROUND: Serum feline pancreatic lipase immunoreactivity (fPLI) and trypsin-like immunoreactivity (fTLI) concentrations are commonly used in cats for the evaluation of pancreatic disease. The effect of kidney disease on these tests in cats are unknown. OBJECTIVE: To investigate the effect of experimentally induced chronic kidney disease (CKD) on serum fPLI and fTLI concentrations. ANIMALS: Surplus serum samples from 20 cats with CKD experimentally induced for an unrelated project and a group of healthy control cats. METHODS: Serum fTLI and fPLI concentrations were compared between groups. RESULTS: Mean (±SD) serum fTLI concentrations in 20 cats with CKD (117.8 ± 63.6 µg/L) were significantly higher than those in healthy cats (n = 32; 46.9 ± 17.5 µg/L; P < .0001). Serum fTLI concentrations in cats with CKD were above the upper limit of the reference interval in 13 of 20 cats (65%). Serum fPLI concentrations were not significantly different between cats with induced CKD (n = 18; 8.6 µg/L; range, 5.4-9.9 µg/L) and healthy cats (n = 41; 7.4 µg/L; range, 5.0-15.2 µg/L; P = .12). All cats with experimentally induced CKD had serum fPLI concentrations within the reference interval. CONCLUSIONS AND CLINICAL IMPORTANCE: Decreased renal function has a clinically relevant impact on serum fTLI concentrations and potentially could interfere with a diagnosis of exocrine pancreatic insufficiency (EPI). Serum fPLI concentration was not affected by experimentally induced CKD and thus serum fPLI may be used for the diagnosis of pancreatitis in cats with kidney disease. Additional studies are needed to verify these results in cats with naturally occurring CKD.

Assessment of copper accumulation in archived liver specimens from cats.

OBJECTIVES: The aim of this study was to assess hepatic copper concentrations and zonal distribution in cat liver specimens. METHODS: For this study, 121 archived, formalin-fixed, paraffin-embedded liver specimens from cats were used. Tissue sections were stained for copper with rhodanine and scored from 0 (no copper accumulation) to 5 (panlobular copper accumulation). The tissue specimens were then deparaffinized and hepatic copper concentrations were measured using flame atomic absorption spectroscopy. RESULTS: Tissue samples were categorized into four groups based on histopathologic findings: (1) no significant histopathologic hepatic changes (n = 66); (2) hepatic steatosis (n = 18); (3) inflammatory or infectious disease (n = 24); and (4) neoplasia (n = 13). Of the 121 specimens, 13 (11%) stained positive for copper, with three having a score ⩾3. Thirty-seven specimens (31%) had copper concentrations above the reference interval ([RI] <180 µg/g dry weight liver). Copper concentrations in cats with hepatic inflammatory or infectious disease were significantly higher than cats with hepatic steatosis (P = 0.03). Copper-staining score and concentration were positively correlated (rs = 0.46, P <0.001). CONCLUSIONS AND RELEVANCE: Despite the fact that 31% of specimens had copper concentrations above the RI, only 11% showed positive copper staining and only 2.5% had a score ⩾3. Our findings suggest that hepatic copper concentrations greater than the upper limit of the RI are relatively common in cats. Further studies to determine the factors that influence hepatic copper staining in cats and to establish contemporary RIs for hepatic copper in healthy cats are warranted.

Short- and long-term effects of amoxicillin/clavulanic acid or doxycycline on the gastrointestinal microbiome of growing cats.

Antibiotic treatment in early life influences gastrointestinal (GI) microbial composition and function. In humans, the resultant intestinal dysbiosis is associated with an increased risk for certain diseases later in life. The objective of this study was to determine the temporal effects of antibiotic treatment on the GI microbiome of young cats. Fecal samples were collected from cats randomly allocated to receive either amoxicillin/clavulanic acid (20 mg/kg q12h) for 20 days (AMC group; 15 cats) or doxycycline (10 mg/kg q24h) for 28 days (DOX group;15 cats) as part of the standard treatment of upper respiratory tract infection. In addition, feces were collected from healthy control cats (CON group;15 cats). All cats were approximately two months of age at enrolment. Samples were collected on days 0 (baseline), 20 or 28 (AMC and DOX, respectively; last day of treatment), 60, 120, and 300. DNA was extracted and sequencing of the 16S rRNA gene and qPCR assays were performed. Fecal microbial composition was different on the last day of treatment for AMC cats, and 1 month after the end of antibiotic treatment for DOX cats, compared to CON cats. Species richness was significantly greater in DOX cats compared to CON cats on the last day of treatment. Abundance of Enterobacteriales was increased, and that of Erysipelotrichi was decreased in cats of the AMC group on the last day of treatment compared to CON cats. The abundance of the phylum Proteobacteria was increased in cats of the DOX group on days 60 and 120 compared to cats of the CON group. Only minor differences in abundances between the treatment groups and the control group were present on day 300. Both antibiotics appear to delay the developmental progression of the microbiome, and this effect is more profound during treatment with amoxicillin/clavulanic acid and one month after treatment with doxycycline. Future studies are required to determine if these changes influence microbiome function and whether they have possible effects on disease susceptibility in cats.