This document describes the HOTIS test, which is used to detect mastitis in bovine milk by detecting the presence of Streptococcus agalactiae. The test involves mixing milk with a pH indicator dye, bromocresol purple, in a test tube. If streptococci that cause mastitis are present, they will produce acid during incubation that changes the color of the dye from purple to yellow, indicating a positive result. Colonies of S. agalactiae appear as canary yellow flakes or balls deposited on the sides of the test tube. The HOTIS test was discovered in 1943 and is a diagnostic procedure for detecting mastitis-causing streptococci in milk.

1. HOTIS TEST
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2. INTRODUCTION
• This test has recently been introduced, and is supposed to be of a useful
diagnostic procedure.
• Used to detect mastitis.
• Discovered in 1943.
• A test for the presence S. agalactiae in bovine mastitis in milk.
• This test is now also used and extended to find mastitis producing
Streptococci.
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3. PROCEDURE
• In this test 9.5 ml of milk is taken in a test tube, add 0.5 ml of bromocresol purple.
• Tube is inverted several times.
• Incubate at 37 degree centigrade for 24 h.
• If positive, canary yellow colonies will be found on the sides of test tube.
• When the dye and milk are first mixed, the color is purple.
• If streptococci are present the color changes during incubation from purple to green or
yellow as a result of acid production.
• If the Streptococcus agalactiae is present small flakes or balls of growth canary yellow in
color became deposited on the side of the tube.
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5. THANK YOU