PCV2

1. A method for eliciting a protective immune response in a pig against Mycoplasma hyopneumoniae ( M. hyo ) comprising administering to said pig a single dose of an immunogenic composition which comprises porcine circovirus type 2 antigen and M. hyo antigen, wherein the amount of the M. hyo antigen per a single dose is equivalent to 40-fold the amount of a determined relative potency value in mice, wherein the relative potency value in mice for M. hyo is determined by the steps:

(a) making serial dilutions of a composition containing an unknown amount M. hyo antigen to be determined to form a plurality of serial dilution groups with each member of each group having the same serial dilution;

(b) dividing a plurality of mice into groups to form a number of mice groups, wherein the number of mice groups is the same as the number of serial dilution groups and each mice group contains a plurality of mice;

(c) administering a single dose of each serial dilution group containing said M. hyo antigen of step (a) to each mouse in a mice group such that each mouse in a mice group receives the same serial dilution and each mice group receives a different serial dilution;

(d) taking a biological sample from each mouse in each mice group for each serial dilution group after a period of 21 days;

(e) detecting M. hyo specific antibodies present in the biological samples of step (d);

(f) determining the relative potency value of the M. hyo composition, wherein the relative potency is equal to the maximal serial dilution at which 100% of mice receiving said single dose of M. hyo antigen of step (c) develop a detectable amount of M. hyo antibodies within 21 days post treatment as detected in an M. hyo specific antibody detection assay of step (e);

(g) calculating the amount of M. hyo antigen to administer to a pig by multiplying the maximal serial dilution amount as determined in step (e) by a factor of 40; and

(h) administering to said pig an immunogenic composition which comprises porcine circovirus type 2 antigen and M. hyo antigen, wherein the amount of the M. hyo antigen per a single dose is equivalent to the calculation of step (g).

2. The method of claim 1 , wherein the amount of porcine circovirus type 2 antigen per a single dose is equivalent to 10-fold the amount of a determined relative potency (RP) value in mice, wherein the RP value in mice for porcine circovirus type 2 antigen is determined by the steps:

(a) making serial dilutions of a composition containing an unknown amount porcine circovirus type 2 antigen to be determined to form a plurality of serial dilution groups with each member of each group having the same serial dilution;

(b) dividing a plurality of mice into groups to form a number of mice groups, wherein the number of mice groups is the same as the number of serial dilution groups and each mice group contains a plurality of mice;

(c) administering a single dose of each serial dilution group containing said porcine circovirus type 2 antigen of step (a) each mouse in a mice group such that each mouse in a mice group receives the same serial dilution and each mice group receives a different serial dilution;

(d) taking a biological sample from each mouse in each mice group for each serial dilution group of step (c) after a period of 21 days;

(e) detecting porcine circovirus type 2 specific antibodies present in the biological samples of step (d);

(f) determining the relative potency value of the porcine circovirus type 2 composition, wherein the relative potency is equal to the maximal serial dilution at which 100% of mice receiving said single dose of porcine circovirus type 2 antigen of step (c) develop a detectable amount of porcine circovirus type 2 antibodies within 21 days post treatment as detected in a porcine circovirus type 2 specific antibody detection assay of step (e);

(g) calculating the amount of porcine circovirus type 2 antigen to administer to a pig by multiplying the maximal serial dilution amount as determined in step (f) by a factor of 10; and

(h) administering to said pig the immunogenic composition which comprises porcine circovirus type 2 antigen and M. hyo antigen, wherein the amount of the porcine circovirus type 2 antigen per a single dose is equivalent to the calculation of step (g).

3. The method according to claim 1 , wherein said immunogenic composition further comprises an adjuvant.

4. The method composition according to claim 3 , wherein the adjuvant is a carbomer.

5. The method according to claim 1 , wherein said immunogenic composition elicits a protective immune response against M. hyo when administered to said pig as a single dose administration.

6. The method according to claim 1 , wherein said immunogenic composition elicits a protective immune response against M. hyo and porcine circovirus type 2 when administered to said pig as a single dose administration.

7. The method according to claim 1 , wherein the immunogenic composition elicits a duration of immunity against M. hyo and/or porcine circovirus type 2 of at least 130 days when administered to said pig.

8. The method according to claim 7 , wherein the immunogenic composition elicits a duration of immunity against M. hyo and/or porcine circovirus type 2 of at least 150 days when administered to said pig.

9. The method according to claim 7 , wherein the immunogenic composition elicits a duration of immunity against M. hyo and/or porcine circovirus type 2 of at least 184 days when administered to said pig.

10. The method according to claim 1 , wherein the specific antibody detection assay is an ELISA.

11. The method according to claim 2 , wherein the specific antibody detection assay for detecting the porcine circovirus type 2 specific antibodies is a modified indirect porcine circovirus (PCV) type 2-based and recombinant capsid protein (ORF2)-based ELISA for the detection of antibodies to PCV.