PMC:5423899 / 5620-13221 JSONTXT

{"project":"2_test","denotations":[{"id":"28540291-18481363-43169047","span":{"begin":7596,"end":7598},"obj":"18481363"}],"text":"Materials and Methods\n\nStudy Population\nCats with chronic vomiting and/or diarrhea were recruited by a multi-center group of primary care veterinarians in the greater Cincinnati region. Cats with at least one episode of vomiting and/or diarrhea per week for a minimum duration of 3 weeks, with no more than three episodes of vomiting daily were included. The vomitus excluded those defined as hairball only but could include hair material if present in addition to food and/or bile. Cats were at least 1 year of age, with a body condition score (BCS) between 2 and 4 on a 5-point scale, and housed exclusively indoors. Cats were excluded if they were fed a veterinary therapeutic diet; had a known food allergy; had a history of undesired weight loss in excess of 10% over the last 2 months; had received antibiotic therapy within the last month; received long-acting immunosuppressive drugs within the past 6 weeks; or had received any immunosuppressive drugs within 3 weeks prior to enrollment.\nCat owners were required to be at least 18 years of age, be the primary caregiver of the cat, be able to monitor the frequency of vomiting and/or diarrhea, and be able to report the daily occurrences via a daily automated phone call from an Interactive Voice Response System (IVRS). Cats from multi-cat households (up to four cats maximum) could be included, but only one cat was eligible to participate in the study and all cats in the house-hold were required to be fed the same study diet. Additionally, the owner had to be able to monitor the frequency and occurrence of vomiting and/or diarrhea from the cat participating in the study.\n\nClinical Screening\nOn day 0, all cats underwent a baseline physical examination and blood was submitted for complete blood count, serum chemistry panel, total serum thyroxine concentration (Total T4), feline pancreas-specific lipase (Spec fPL), and serum cobalamin and folate testing. Viral screening consisted of feline coronavirus (FCoV) antibody by indirect fluorescent antibody and feline leukemia virus (FeLV) antigen and feline immunodeficiency virus (FIV) antibody by ELISA. Fecal examination included wet smear and zinc sulfate centrifugation flotation and a feline diarrhea PCR panel to detect Campylobacter coli, Campylobacter jejuni, Clostridium perfringens enterotoxin gene, Cryptosporidium spp., FCoV, feline panleukopenia virus, Giardia spp., Salmonella spp., Toxoplasma gondii, and Tritrichomonas fetus. Cats were excluded if diagnostic tests identified any systemic or infectious disease that could be associated with the clinical signs of vomiting or diarrhea, including, but not limited to FeLV, FIV, hepatic disease, renal disease, and hyperthyroidism. Cats were also excluded if they were panhypoproteinemic, hypoalbuminemic, hypocobalaminemic, or had a Spec fPL ≥5.4 µg/L. Cats that tested positive for FCoV antibody, C. perfringens enterotoxin gene, C. coli, and FCoV via the PCR fecal panel were not excluded from the study. All diagnostic analyses were conducted at a third party commercial laboratory.1\n\nStudy Diets\nCats were randomized to be fed one of two commercial veterinary therapeutic dry gastrointestinal formulas, Diet A2 or Diet B.3 No additional foods or treats were permitted. All investigators and participants were masked to the identity of the diet. Study diets were re-packaged into white bags, sealed, and delivered directly to participating veterinary clinics by plant employees not participating in the study. Nutrient analysis (conducted internally at Iams Analytical Laboratory), caloric distribution, and ingredient composition is summarized in Table 1. Cats were fed according to each product’s feeding guidelines to maintain body weight.\nTable 1 Nutrient analysis, caloric distribution, and ingredient composition of study diets fed to 28 cats with chronic gastroenteropathy. Nutrient analysis conducted at the Iams Pet Care Analytical Lab; AF, as fed; NFE, nitrogen-free extract, determined as 100% − (% moisture + % protein + % fat + % ash + % crude fiber); ME, metabolizable energy.\n\nStudy Design\nOn day 0, cats that met all of the inclusion criteria were randomized to receive either Diet A or Diet B. The randomization was balanced by site, presence of diarrhea, and the owner reported weekly average number of vomiting and/or diarrhea episodes. Randomization was conducted with an internally developed balance and assignment program through an electronic case record form. Withdrawal criteria included any identified condition that required immediate medical care. Owners were trained to use the feline Fecal Consistency Scale (FCS; Figure 1) and to respond to the daily IVRS phone call. On days 1–28, owners received daily IVRS phone calls to record the number of vomiting episodes and presence of diarrhea over the 24-h period. A diary was provided to track daily observations and to record daily FCS scores. Owners were instructed to call the veterinary clinic if the cat did not consume the food, had a reduced appetite, reduction in body weight, or any other concerns. On day 14, the owner was called by a veterinary technician to confirm that cat was eating well, had not lost weight, and did not have any concerns or significant decline in their clinical condition. On day 28, the cats returned to the clinic for a final examination and diagnostic recheck (CBC, serum chemistry profile, and Spec fPL).\nFigure 1 Vomiting occurrences with 95% confidence intervals in 28 cats with chronic gastroenteropathy fed one of two different veterinary therapeutic diets.\n\nStatistical Methods\nThe weekly episodes of vomiting and diarrhea were analyzed with a mixed-effects negative binomial generalized linear model. Fixed effects in the model were week, diet, and the interaction between. The random effects were animal nested within clinic. For vomiting, the change from week 0 to weeks 1–4 for each diet and between diets was tested. For diarrhea, the change from week 1 to weeks 2–4 for each diet and between diets was tested.\nThe negative binomial models were also used to test for an effect of positive fecal testing for FCoV, C. perfringens enterotoxin gene, and FCoV antibody on vomiting and diarrhea occurrences by changing the fixed effects to week and positive/negative and retaining the same contrasts. This same model was altered to have a response of the total vomiting occurrences over the 4 weeks and fixed effects of diet and age. Vomiting was also modeled against the initial Spec fPL values using a negative binomial model, as before, however with the change in vomiting from baseline as the response and the fixed effect of Spec fPL results. The fecal scores were modeled using a linear mixed-effects model with fixed effects of day, diet, and the interaction between and a random effect of cat.\nThe binary data calculated from the vomiting occurrences was analyzed with a mixed-effects binomial model, using a logit link function. As before, the fixed effects were week, diet, and interaction between. Random effects were animal nested within clinic. The same hypothesis tests were also performed comparing the change between weeks within and between diets.\nAll contrasts performed using the mixed-effects models were corrected for the multiple comparisons using stepwise correction, to achieve a family wise error rate of 5% within each measure. The hypothesis tests of correlations were corrected using the false discovery rate method of Benjamini–Hochberg, to the 5% level. These analyses were performed in R v3.2.0 (10) statistical software with libraries lme4 (11) and multcomp (12).\n"}