Objectives The aim of the study was to determine whether feline coronavirus (FCoV) RNA in effusion samples can be used as a diagnostic marker of feline infectious peritonitis (FIP); and in FCoV RNA-positive samples to examine amino acid codons in the FCoV spike protein at positions 1058 and 1060 where leucine and alanine, respectively, have been associated with systemic or virulent (FIP) FCoV infection. Methods Total RNA was extracted from effusion samples from 20 cats with confirmed FIP and 23 cats with other diseases. Feline coronavirus RNA was detected using a reverse transcriptase quantitative polymerase chain reaction assay (qRT-PCR), and positive samples underwent pyrosequencing of position 1058 with or without Sanger sequencing of position 1060 in the FCoV spike protein. Results Seventeen (85%) of the effusion samples from 20 cats with FIP were positive for FCoV RNA, whereas none of the 23 cats with other diseases were positive. Pyrosequencing of the 17 FCoV-positive samples showed that 11 (65%) of the cats had leucine and two (12%) had methionine at position 1058. Of the latter two samples with methionine, one had alanine at position 1060. Conclusions and relevance A positive FCoV qRT-PCR result on effusions appears specific for FIP and may be a useful diagnostic marker for FIP in cats with effusions. The majority of FCoVs contained amino acid changes previously associated with systemic spread or virulence (FIP) of the virus.

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms The most common cause of lower urinary tract signs (LUTS) in cats under the age of 10 6 years is feline idiopathic cystitis (FIC). The prevalence of LUTS in the UK pet cat 7 population is difficult to assess. This study used data collected prospectively to 8 investigate the prevalence of, and risk factors for, owner-reported LUTS in a cohort of 9 young pet cats. Methods 12Cat owners were recruited onto a long-term longitudinal study and asked to complete 13 questionnaires at specified age-points for their cats. Results 23The prevalence of owner-reported LUTS in cats seen urinating by the owner was 4.3%, Methods 77Cat owners were recruited onto a long-term longitudinal study and asked to complete Results 88The prevalence of owner-reported LUTS in cats seen urinating by the owner was 4.3%, Conclusions and relevance 97The prevalence of owner-reported LUTS in a cohort of young pet cats was higher than