Page 307 - The Veterinary Laboratory and Field Manual 3rd Edition

276 Susan C. Cork and Roy Halliwell

5 Hugh-Liefson medium and Bromothymol blue
(3´,3´Dibromothymolsulfonephthalein) are all
available from various suppliers (Appendix 4).
6 Koser citrate medium is available from various sup-
pliers (see Appendix 4) in 100 and 500 g units.
7 Rabbit plasma can be bought from standard com-
mercial suppliers of immunological reagents.
8 TSI is available from reagent suppliers (Appendix
4). Instructions for the production and handling of
TSI are supplied with the medium. It is useful to
keep a range of product catalogues as these often
Figure 4.38 MinIon sequencing device (Oxford contain methods, additional information and refer-
Nanopore Technologies). ences which may be useful.
9 Methyl red (4-Dimethylaminoazobenzene-2´-
carboxylic acid) pH 4.2 (pink)–pH 6.2 (yellow)
it takes for the molecule to travel the length of available from suppliers (Appendix 4).
the flight tube. The spectrum created from the 10 α-naphthol and creatine are available from suppli-
ers (Appendix 4).
sample is characteristic of the organism and is 11 Sulfanilic acid (4-aminobenzene sulfonic acid) is
compared to profiles in a database of known available from suppliers (Appendix 10.4).
organisms to predict its likely identity (Singhal 12 Oxidase reagent (NN-dimethyl-P-phenylenediamine
et al., 2015) (Figure 4.38). oxalate) darkens readily when exposed to air and is
available from suppliers (Appendix 10.4).
13 Urea Agar Base (Christensen) available from sup-
pliers as a base media in 500g units (Appendix
Endnotes 10.4)
14 Motility test medium (Tryptose, agar and sodium
1 To prepare a wet smear: emulsify the specimen chloride) available from suppliers (Appendix 10.4)
on a microscope slide with a small drop of saline, 15 http://clsi.org/.
iodine or a specific stain, (India ink, or methylene 16 See the OIE Register of diagnostic kits for veteri-
blue, for example). Carefully place a coverslip over nary use http://www.oie.int/scientific-expertise/
the suspension taking care that fluid does not go registration-of-diagnostic-kits/the-register-of-
beyond the edges of the coverslip. This can then be diagnostic-kits/.
examined under the microscope. 17 TCID = Total cell infective dose (50) or the
50
2 The GasPak system is available commercially and amount of a pathogenic agent that will produce
a new packet of chemicals must be used each time. pathological change in 50% of cell cultures inocu-
Typical constituents of GasPak sachets are as fol- lated. Expressed as TCID /ml.
50
lows: 18 Test development and validation is well explained
in the OIE Manual of Diagnostic Tests and Vaccines
1 sodium borohydride – NaBH4 for Terrestrial Animals at http://www.oie.int/stan-
2 sodium bicarbonate – NaHCO3 dard-setting/terrestrial-manual/access-online/.
3 citric acid – C3H5O (COOH)3 19 http://www.ncbi.nlm.nih.gov/genbank/.
4 cobalt chloride – CoCl2 (catalyst).
20 https://www.luminexcorp.com/clinical/infectious-
3 See Table 4.2b. There are a range of haemolysins disease/respiratory-disease/respiratory-pathogens-
present in bacteria. Some bacterial colonies have a flex-test/.
clear area around them on blood agar although this 21 http://www.cdc.gov/pulsenet/.
varies in appearance and size depending on the type 22 http://www.cdc.gov/pulsenet/.
of haemolysin present. 23 http://primerexplorer.jp/e/.
4 Available from suppliers of reagents (see Appendix 24 http://pubmlst.org/.
5) usually in 25 or 100 mg vials. 25 GenBank: http://www.ncbi.nlm.nih.gov/genbank/.

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