Variability of lysozyme and lactoferrin bioactive protein concentrations in equine milk in relation to LYZ and LTF gene polymorphisms and expression.
BACKGROUND
Equine milk is considered to be an interesting product for human nutrition, mainly owing to its low allergenicity and significant amounts of bioactive proteins, including lysozyme (LYZ) and lactoferrin (LTF). The present study assessed the effect of genetic factors on LYZ and LTF concentration variability in mare's milk.


RESULTS
Significant effects of horse breed and lactation stage on milk LYZ and LTF contents were observed. The highest level of LTF and the lowest concentration of LYZ were recorded for the Polish Warmblood Horse breed. The highest amounts of both proteins were found for the earliest investigated time point of lactation (5th week). Altogether 13 (nine novel) polymorphisms were found in the 5'-flanking regions of both genes, but they showed no significant relationship with milk LYZ and LTF contents. Several associations were found between selected SNPs and the LYZ gene relative transcript level.


CONCLUSIONS
While the present study indicated the existence of intra- and interbreed variability of LYZ and LTF contents in mare's milk, this variation is rather unrelated to the 5'-flanking variants of genes encoding both proteins. This study is a good introduction for broader investigations focused on the genetic background for variability of bioactive protein contents in mare's milk. © 2016 Society of Chemical Industry.
Department of Horse Breeding, Poznan University of Life Sciences, Wolynska 33, PL-60-637, Poznan, Poland.
Jakub
http://orcid.org/0000-0001-6936-2550
J
Cieslak
Department of Horse Breeding, Poznan University of Life Sciences, Wolynska 33, PL-60-637, Poznan, Poland.
Lukasz
L
Wodas
Department of Horse Breeding, Poznan University of Life Sciences, Wolynska 33, PL-60-637, Poznan, Poland.
Alicja
A
Borowska
Department of Horse Breeding, Poznan University of Life Sciences, Wolynska 33, PL-60-637, Poznan, Poland.
Jan
J
Sadoch
Department of Genetics and Animal Breeding, Poznan University of Life Sciences, Wolynska 33, PL-60-637, Poznan, Poland.
Piotr
P
Pawlak
Department of Animal Science, Cattle Breeding Division, Warsaw University of Life Sciences, Ciszewskiego 8, PL-02-786, Warsaw, Poland.
Kamila
K
Puppel
Department of Animal Science, Cattle Breeding Division, Warsaw University of Life Sciences, Ciszewskiego 8, PL-02-786, Warsaw, Poland.
Beata
B
Kuczynska
Department of Horse Breeding, Poznan University of Life Sciences, Wolynska 33, PL-60-637, Poznan, Poland.
Mariusz
M
Mackowski
D000818:Animals; D001947:Breeding; D005260:Female; D005838:Genotype; D006736:Horses / Q000235:genetics* / Q000378:metabolism; D007774:Lactation; D007781:Lactoferrin / Q000235:genetics* / Q000502:physiology; D008892:Milk / Q000737:chemistry* / Q000378:metabolism; D009113:Muramidase / Q000235:genetics* / Q000378:metabolism; D011110:Polymorphism, Genetic
D009113:Muramidase; D007781:Lactoferrin
equine milk; gene expression; lactoferrin; lysozyme; polymorphism