11 Open Access Int. J. Trop. Vet. Biomed. Res. Vol. 7 (2): 11-14; November 2022 www.jurnal.unsyiah.ac.id/IJTVBR E-ISSN : 2503-4715 Use of Vinegar as A Candidate Substitute Of Acetic Acid (CH3COOH) in The Rivalta Test Method in Diagnosis Feline Infectious Peritonitis (FIP) Domestic Cat Zuraidawati¹, Maryulia Dewi 2 , Nanda Yulian Syah 3 , Rumi Sahara Zamzami 3 1 Laboratory of Clinic Faculty of Veterinary Medicine, Syiah Kuala University, Darussalam, Banda Aceh 23111, Indonesia 2 Laboratory of Microbiology Faculty of Veterinary Medicine, Syiah Kuala University, Darussalam, Banda Aceh 23111, Indonesia *Corresponding author: zuraidawati@unsyiah.ac.id Abstract This study aims to test the samples of abdominal fluid from cats suspected of having FIP by using vinegar as a substitute for acetic acid in the rival method. Feline Infectious Peritonitis (FIP) is a viral disease that is not zoonotic, but is very fatal with an infectious prognosis in various types of cats and it’s transmitted orally. This study aims to determine the positive or negative results of FIP infection in cats. The diagnosis of FIP can be seen through clinical symptoms such as lack of appetite, diarrhea, weakness, dehydration (reaching 8%), Body Condition Score (BCS) 2, enlarged abdomen, and ultrasound results showing ascites and swollen kidneys. This study uses vinegar as a substitute for acetic acid in the rival method. The test was carried out experimentally in a laboratory. The research data were analyzed descriptively, the results of a positive FIP reaction were indicated by the presence of a cloudy jellyfish-shaped precipitate in the test tube. Keywords: vinegar, feline infectious peritonitis, acetic acid Background Feline Infectious Peritonitis (FIP) is caused by a corona virus with a high mortality rate in cats, especially in kittens. The virus is a type of protein-coated single- stranded RNA virus from the Coronaviridae family. The FIP virus is a virulence form of Feline Enteric Coronavirus (FECV) which develops with enteric mutations. FECV (non-lethal) and FIPV (lethal) that can infect simultaneously in the body (Abbas et al., 2014). Defining the diagnosis of FIP is difficult, especially at the beginning period of the infection. This is due to the expensive testing fee to detect the FIP virus in cats such as the FIP rapid test. As a result of unclear clinical signs of FIP in cats, and occurs together with other diseases, often causing delays in diagnosis and treatment. As an alternative to using the expensive FIP rapid test, diagnosing FIP cases in cats can also be done by examining the protein and albumin levels of the cat's peritoneal fluid using the rivalta test method, but the reagents in this test requires acetic acid (CH3COOH) which is also difficult to obtain. The rivalta test is a very simple test, but due to the limited availability of acetic acid, not all veterinary clinics offer this test. A very simple alternative as a substitute for acetic acid with a similar chemical composition is to use vinegar. Vinegar is often used as a cooking additive, very acidic, with a pH of about 2.5. Vinegar usually containing 4-18% of acetic acid, it can be obtained easily at a relatively cheap price compared to the Rapid test and Rivalta test using the CH3COOH reagent. Based on the problems above, it is necessary to conduct an experiment to study the use of vinegar as a substitute for acetic acid (CH3COOH) to detect FIP infection in cats. Materials and Methods The tools and materials used in this study were a stethoscope, thermometer, surgical/minor set (scissors, scalpel, and tweezers), 3 ml syringe, test tube, distilled water, vinegar, and a cat diagnosed with FIP.