Sequences diagnostic for shrimp pathogens

1. A pair of Vibrio harveyi diagnostic primer sequences as set forth in SEQ ID NO:1 and SEQ ID NO:2.

2. A kit for the detection of Vibrio harveyi comprising the pair of Vibrio harveyi diagnostic primer sequences of claim 1 .

3. The kit for the detection of Vibrio harveyi according to claim 2 wherein the kit further comprises at least one reagent selected from the group consisting of a thermostable polymerase, a mixture of four different deoxynucleotide triphosphates, a nucleic acid-binding fluorescent molecule, at least one pair of internal sample control primers, at least one internal template control and at least one pair of internal template control primers, and a probe comprising a complementary sequence to a portion of at least one region of nucleic acid within the Vibrio harveyi genome which is capable of being amplified with the pair of Vibrio harveyi diagnostic primer sequences.

4. A method for detecting the presence of Vibrio harveyi in a sample comprising:

(i) providing DNA from a sample suspected of containing Vibrio harveyi ; and

(ii) amplifying the DNA with a pair of Vibrio harveyi diagnostic primer sequences as set forth in SEQ ID NO:1 and SEQ ID NO:2 such that amplification products are generated;

wherein the presence of amplification products confirms the presence of Vibrio harveyi.

5. The method for detecting the presence of Vibrio harveyi in a sample according to claim 4 wherein the amplifying of (ii) is done using the polymerase chain reaction.

6. The method for detecting the presence of Vibrio harveyi in a sample according to claim 4 wherein the amplifying of (ii) is done in the presence of a nucleic acid-binding fluorescent agent or a fluorescently labeled probe and the presence of amplification products is confirmed using fluorescence detection.

7. The method according to claim 6 wherein the fluorescently labeled probe is selected from the group consisting of SEQ ID NO:8 and SEQ ID NO:9.

8. The method according to claim 4 wherein at least one pair of internal sample control primers is included in the amplifying of (ii) to produce an internal sample control product.

9. The method according to claim 8 wherein the at least one pair of internal sample control primers is selected from the group consisting of SEQ ID NOs:4 and 5, and SEQ ID NOs:6 and 7.

10. The method according to claim 4 wherein at least one pair of internal template control primers and at least one internal template control are included in the amplifying of (ii) to produce an internal template control product.

11. A method for quantifying the amount of Vibrio harveyi in a sample comprising:

(i) providing DNA from a sample suspected of containing Vibrio harveyi;

(ii) amplifying the DNA with a pair of Vibrio harveyi diagnostic primer sequences as set forth in SEQ ID NO:1 and SEQ ID NO:2 by thermal cycling between at least a denaturing temperature and an extension temperature in the presence of a nucleic acid-binding fluorescent agent or a fluorescently labeled probe;

(iii) measuring the amount of fluorescence generated by the nucleic acid-binding fluorescent agent or the fluorescently labeled probe during the thermal cycling;

(iv) determining a cycle threshold number at which the amount of fluorescence generated by the nucleic acid-binding fluorescent agent or the fluorescently labeled probe reaches a fixed threshold value above a baseline value; and

(v) calculating the amount of Vibrio harveyi in the sample by comparing the cycle threshold number determined for the Vibrio harveyi in the sample with a standard curve of the cycle threshold number versus the logarithm of template concentration determined using standard solutions of known concentration.

12. The method according to claim 11 wherein the fluorescently labeled probe is selected from the group consisting of SEQ ID NO:8, and SEQ ID NO:9.

13. The method according to any of claim 4 , or 11 wherein the method further comprises the steps of:

a) treating an environment from which the sample was obtained with a chemical treatment to kill or control the Vibrio harveyi ; and

b) repeating the steps of the method of claim 4 , or 11 on another sample taken from the environment in order to assess Vibrio harveyi inactivation by the chemical treatment.

14. The method according to any of claim 4 , or 11 wherein the method further comprises the step of: treating an environment from which the sample was obtained with a chemical treatment to kill or control the Vibrio harveyi in order to improve health and grow-out of shrimp.