Funding for this research was provided by:
Narodowe Centrum Nauki (2011/03/B/NZ9/03987)
Received: 31 December 2016
Accepted: 23 January 2018
First Online: 31 January 2018
: This study complies with national and institutional guidelines of the use of animals in research according to the Polish Legal Act of January 21, 2005. Since sample collection was performed during routine slaughter and no additional procedures that were harmful or painful for the animals were applied, this study did not require a formal ethics approval.
: Not Applicable
: The authors declare that they have no competing interests.
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