I`m running a two trait model, wich contains 4 fixed effects, 1 covariate and 1 uncorrelated effect each (permanent environment) (all the same for both traits, actually). Parameter file contains 4000 observations. Found no problems with contemporary group settings, neither in "progeny by sire" observations (inside each CG).

I`ve tried starting MTDFRUN with all covariances set to 0(zero) and MTDF76 shows me variances very similar to the ones I get in separate single trait model analysis. After that, started it with variances held constant in the values estimated by univariate models. Even then, MTDFREML keeps converging to correlation coefficients = 1.

Does anyone have any ideas on what can be happening here?

Thanks in advance. 

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