00539naa#a2200181#i#450# EN\\bibl\4843 20260323032933.1 2073-0462 20141225b2014####ek#y0engy0150####ca RUS RU THE DEPENDENCE OF EGG PRODUCTION OF LAYING HENS ON THE COMPOSITION OF ENZYME PREPARATIONS Journal article Kazan Kazan state agrarian University 2014 2 с. Journal article local Ivanova Elena Lavrentev Anatoliy zh-szf.ru