Prolactin polymorphism effect over production traits types at Transylvanian Merino sheep

Mihail Alexandru Gras, Catalin Mircea Rotar, Rodica Stefania Pelmus, Cristina Lazar, Elena Ghita, Horia Grosu


Worldwide were developed animal selection programs assisted by molecular markers at many local breeds, targeting biodiversity and intrinsic value preservation.

Until now, were considered molecular markers associated with milk (beta-lactoglobulin, caseins) and meat production (calpastatin, miostatin etc.).

Another important marker for milk production is prolactin. Previous studies prove that prolactin depletion is associated with milk secretion decrease, making codifying gene for prolactin a candidate gene for milk production variation.  Correlation of this marker effect with meat quality parameters was not studied yet.

Objective of this study is estimation of prolactin gene polymorphism effect over two traits types (for milk and meat quality) with a view to simultaneous use of both types in selection programs.

Using genomic DNA isolated from blood, we evaluate prolactin genetic polymorphism of 50 Transylvanian Merino sheep through PCR-RFLP method.  The effect of prl polymorphism over production traits was estimated using animal model.

The research results reveal an important effect of prl gene over productive quality traits. The alleles effect is similar between those types; this fact sustain common selection program development in the same population

In conclusion, our study proved that prl gene can be an important marker for selection programs in local sheep breeds.


marker assisted selection, meat traits, milk traits, PCR-RFLP, prolactin

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