Dorothy P. Laflamme

Pet feeding practices of dog and cat owners in the United States and Australia

Most pet dogs and cats in developed countries are fed commercial foods, but there is growing interest in the use of noncommercial foods for pets, including homemade and raw food diets. A survey of dog and cat owners in the United States and Australia revealed that > 90% of pets were fed commercial foods, but that noncommercial foods comprised at east 25% of the diet for 17.3% of dogs and 6.3% of cats.

The effects of weight loss on adipokines and markers of inflammation in dogs

Evidence suggests that adipose tissue-derived adipokines induce mild inflammation and may play a role in insulin resistance associated with diabetes. The present study was designed to examine a series of adipokines and markers of inflammation in dogs before and after a successful weight loss. The study included fasting serum samples from twenty-five dogs before and after a weight-loss programme. Serum C-reactive protein (CRP) and monocyte chemoattractant protein-1 (MCP-1) were measured as indicators of chronic inflammation, while serum adipokines including total adiponectin, high-molecular-weight (HMW) adiponectin, resistin and leptin were also examined. Medians for CRP (before, 10.0 (interquartile range 5.4-15.0) μg/ml; after, 5.6 (interquartile range 3.8-7.0) μg/ml) and MCP-1 (before, 212 (interquartile range 157-288) ng/ml; after, 185 (interquartile range 143-215) ng/ml) decreased significantly after weight loss. Medians for resistin showed a mild, yet significant reduction (before, 67.1 (interquartile range 44.4-88.5) pg/ml; after, 60.5 (interquartile range 32.3-67.1) pg/ml), while leptin showed a dramatic decrease after weight loss (before, 18.9 (interquartile range 10.8-35.4) ng/ml; after, 6.6 (interquartile range 3.9-10.2) ng/ml). Serum total adiponectin and HMW adiponectin were unchanged on all analyses performed. These data suggest that weight loss can decrease chronic inflammation; however, the clinical implications of this decrease are not well elucidated in dogs. Surprisingly, there was no increase in total or HMW serum adiponectin after weight loss, as observed previously in human subjects. The lack of change in total and HMW adiponectin might explain why insulin resistance and type 2 diabetes are less prevalent in obese dogs when compared with humans and cats.

Effects of dietary sodium chloride on health parameters in mature cats.

High sodium diets have been shown to enhance water intake and urine output, a potential benefit in the management of lower urinary tract diseases. However, one study suggested that high salt (sodium chloride) diets might have adverse effects on the kidneys [Kirk CA, Jewell DE, Lowry SR. Effects of sodium chloride on selected parameters in cats. Vet Ther 2006; 7: 333–46]. Therefore, the objective of this controlled, prospective study was to evaluate the effects of diets with different salt content (1.11% sodium and 1.78% chloride versus 0.55% sodium and 1.02% chloride, dry matter (dm)) when fed to mature cats (mean age 7.0 years; 12 cats per group) over a 6-month period. Food intake, body weight, bone mineral content, total body hydration status, blood pressure, and markers of renal function were unaffected by salt intake, and no adverse effects were observed. When a subset of cats (n=9) with an initial serum creatinine ≥1.6 mg/dl was evaluated separately, there remained no evidence of adverse effects associated with increased salt intake. These results are consistent with the majority of other studies evaluating sodium intake in cats, as well as with the National Research Councils assessment, all of which indicate that sodium at 1.5% of the diet dm is not harmful to healthy cats.

Correlation of a feline muscle mass score with body composition determined by dual-energy X-ray absorptiometry.

Body condition scoring (BCS) systems primarily assess body fat. Both overweight and underweight animals may have loss of lean tissue that may not be noted using standard BCS systems. Catabolism of lean tissue can occur rapidly, may account for a disproportionate amount of body mass loss in sick cats and can have deleterious consequences for outcome. Therefore, along with evaluation of body fat, patients should undergo evaluation of muscle mass. The aims of the present study were first to evaluate the repeatability and reproducibility of a 4-point feline muscle mass scoring (MMS) system and second to assess the convergent validity of MMS by dual-energy X-ray absorptiometry (DXA). MMS was as follows: 3, normal muscle mass; 2, slight wasting; 1, moderate wasting; 0, severe wasting. For the first aim, forty-four cats were selected for evaluation based on age and BCS, and for the second aim, thirty-three cats were selected based on age, BCS and MMS. Cats were scored by ten different evaluators on three separate occasions. Body composition was determined by DXA. Inter- and intra-rater agreement were assessed using kappa analysis. Correlation between MMS and BCS, age, percentage lean body mass and lean body mass (LBM) was determined using Spearmans rank-order correlation. The MMS showed moderate inter-rater agreement in cats that scored normal or severely wasted (κ = 0.48-0.53). Intra-rater agreement was substantial (κ = 0.71-0.73). The MMS was significantly correlated with BCS (r 0.76, P < 0.0001), age (r - 0.75, P < 0.0001), LBM (g) (r 0.62, P < 0.0001) and percentage LBM (r - 0.49, P < 0.0035). Additional investigation is needed to determine whether the MMS can be refined and to assess its clinical applicability.

Attitudes of pet owners toward pet foods and feeding management of cats and dogs.

Patient motion is an important consideration in modern PET image reconstruction. Advances in PET technology mean motion has an increasingly important influence on resulting image quality. Motion-induced artefacts can have adverse effect on clinical outcomes, including missed diagnoses and oversized radiotherapy treatment volumes. This review aims to summarise the wide variety of motion correction techniques available in PET and combined PET/CT and PET/MR, with a focus on the latter. A general framework for the motion correction of PET images is presented, consisting of acquisition, modelling and correction stages. Methods for measuring, modelling and correcting motion and associated artefacts, both in literature and commercially available, are presented, and their relative merits are contrasted. Identified limitations of current methods include modelling of aperiodic and/or unpredictable motion, attaining adequate temporal resolution for motion correction in dynamic kinetic modelling acquisitions, and maintaining availability of the MR in PET/MR scans for diagnostic acquisitions. Finally, avenues for future investigation are discussed, with a focus on improvements that could improve PET image quality, and that are practical in the clinical environment. This article is protected by copyright. All rights reserved.

Discrepancy between use of lean body mass or nitrogen balance to determine protein requirements for adult cats

This study was undertaken to contrast the minimum protein intake needed to maintain nitrogen balance or lean body mass (LBM) in adult cats using a prospective evaluation of 24 adult, neutered male cats fed one to three different diets. Following a 1-month baseline period during which all cats consumed a 34% protein diet, cats were fed a 20% (LO), 26% (MOD) or 34% (HI) protein diet for 2 months. During the baseline period and following the 2-month feeding period, nitrogen balance was assessed using a 96-h complete collection of urine and feces, and LBM was assessed using dual energy X-ray absorptiometry. Weight loss increased in a linear manner with decreasing protein intake (P <0.01), despite no significant difference in calorie intake. Linear regression of the data indicated that approximately 1.5 g protein/kg (2.1 g/kg0.75) body weight is needed to maintain nitrogen balance, while 5.2 g protein/kg (7.8 g/kg0.75) body weight is needed to maintain LBM. This study provides evidence that nitrogen balance studies are inadequate for determining optimum protein requirements. Animals, including cats, can adapt to low protein intake and maintain nitrogen balance while depleting LBM. Loss of LBM and an associated reduction in protein turnover can result in compromised immune function and increased morbidity. Current Association of American Feed Control Officials (AAFCO) and National Research Council (NRC) standards for protein adequacy may not provide adequate protein to support LBM. The minimum daily protein requirement for adult cats appears to be at least 5.2 g/kg (7.8 g/kg0.75) body weight, well in excess of current AAFCO and NRC recommendations. Further research is needed to determine the effect, if any, of body condition, age and gender on protein requirements.

Fecal Microbiota of Cats with Naturally Occurring Chronic Diarrhea Assessed Using 16S rRNA Gene 454-Pyrosequencing before and after Dietary Treatment

Background The gastrointestinal (GI) microbiota has a strong impact on the health of cats and these populations can be altered in GI disease. Little research has been done to associate improvement in diarrhea with changes in GI microbiota. Objective To evaluate GI microbiota changes associated with diet change and related improvement in diarrhea in cats with chronic naturally occurring diarrhea. Animals Fifteen adult Domestic Shorthair cats with naturally occurring chronic diarrhea. Methods Controlled crossover dietary trial for management of diarrhea. Fecal microbiome was assessed using 454‐pyrosequencing. Relationships among fecal score (FS), diet, and microbiome were explored using partial least square method, partial least square method – discriminant analysis, and orthogonal partial least square method with discriminant analysis (OPLS‐DA). Results Dominant bacterial phyla included the Firmicutes and Bacteroidetes, followed by Fusobacteria, Proteobacteria, Tenericutes, and Actinobacteria. Orthogonal partial least squares (OPLS‐DA) clustering showed significant microbial differences within cats when fed Diet X versus Diet Y, and with Diet Y versus baseline. Significant correlations were found between the microbiome and FSs. Those bacteria with the strongest correlation with FS included Coriobacteriaceae Slackia spp., Campylobacter upsaliensis, Enterobacteriaceae Raoultella spp., Coriobacteriaceae Collinsella spp., and bacteria of unidentified genera within the families of Clostridiales Lachnospiracea and Aeromonadales Succinivibrionacease, suggesting that increased numbers of these organisms may be important to gut health. Conclusions and Clinical Importance Alterations in intestinal microbiota were associated with improvement in diarrhea, but, from our data we cannot conclude if changes in the microbiome caused the improvement in diarrhea, or vice versa.

Effect of diets differing in fat content on chronic diarrhea in cats.

BACKGROUND Fat-restricted diets have been advocated for dogs with diarrhea for many years. Recommendations for cats with diarrhea have varied between low-fat and high-fat diets, but there have been no published studies to support either recommendation. OBJECTIVES The objective of this study was to compare the clinical responses of cats with chronic diarrhea to dietary management using either a high fat or a low fat, highly digestible diet. ANIMALS Sixty pet cats with chronic diarrhea were recruited; 55 cats completed the study. METHODS Randomized, double-blinded, controlled clinical trial. Upon completion of baseline measures, cats were fed 1 of 2 diets for 6 weeks, during which the owners recorded fecal scores daily using an illustrated fecal score chart ranging from 0 (very watery) to 100 (firm and dry). After 6 weeks, cats were reevaluated by the attending veterinarians. RESULTS Fecal scores improved significantly, with 78.2% of cats improving by at least 25 points on the 100-point scale or having a final fecal score of at least 66. Over one third of the cats developed normal stools. There were no differences in clinical responses between the diets. Clinical improvement was noted within the 1st week, and maximized within 3 weeks. CONCLUSIONS AND CLINICAL IMPORTANCE These results show that dietary management can be helpful in cats with chronic diarrhea, but dietary fat content does not appear to affect the outcome. Cats that do not respond within 3 weeks should be evaluated further.

Evaluation of canned therapeutic diets for the management of cats with naturally occurring chronic diarrhea

Dietary therapy plays an important role in the management of most gastrointestinal disorders. This study was designed to test the efficacy of a new therapeutic diet for cats with diarrhea, compared to the top selling brand. Sixteen adult cats with chronic diarrhea were grouped and assigned to diet X (Hill’s Prescription Diet i/d Feline) or diet Y (Purina Veterinary Diets EN Gastroenteric Feline Formula). Following baseline evaluations, cats were fed their assigned test diet for 4 weeks. Fecal scores (FS; 7 = very watery; 1 = extremely dry and firm) were recorded daily during the last week on each diet. Each cat was then switched to the alternate test diet and the procedure was repeated. Fifteen cats completed the study. Both therapeutic diets resulted in a significant improvement in average FS and diet Y also resulted in significantly better results compared with diet X. Average FS improved at least one unit in 40% of the cats while fed diet X and in 67% of the cats while fed diet Y, resulting in normal stools (average FS ≤ 3) in 13.3% of cats fed diet X and 46.7% of cats fed diet Y. This study confirms the value of dietary change in the management of chronic diarrhea in cats.

Expression Profiling of Circulating MicroRNAs in Canine Myxomatous Mitral Valve Disease.

MicroRNAs (miRNAs) are small non-coding RNAs that have shown promise as noninvasive biomarkers in cardiac disease. This study was undertaken to investigate the miRNA expression profile in dogs with myxomatous mitral valve disease (MMVD). 277 miRNAs were quantified using RT-qPCR from six normal dogs (American College of Veterinary Internal Medicine Stage A), six dogs with MMVD mild to moderate cardiac enlargement (ACVIM Stage B1/B2) and six dogs with MMVD and congestive heart failure (ACVIM Stage C/D). Eleven miRNAs were differentially expressed (False Discovery Rate < 0.05). Dogs in Stage B1/B2 or C/D had four upregulated miRNAs, including three cfa-let-7/cfa-miR-98 family members, while seven others were downregulated, compared to Stage A. Expression of six of the 11 miRNAs also were significantly different between dogs in Stage C/D and those in Stage B1/B2. The expression changes were greater as disease severity increased. These miRNAs may be candidates for novel biomarkers and may provide insights into genetic regulatory pathways in canine MMVD.