The experiment was carried out in poultry farm LLP "Saru Bulak" in Almaty region on laying hens breed "Hajseks white". The flock of medium weight laying hens in the first half of their production cycle (24 week of age) was randomly allocated to five-tier battery hens of 20 laying hens each, under conventional conditions of ventilation, temperature (17-19°C) and lighting (16 h light d-1). All birds had a free access to diets and water and fed with a standard industrial diet of the LLP "Saru bulak". The protocol for this study was approved by the local Animal Experimentation Ethics Committee. Feed mixtures contained the same components, the only difference was that the mixtures designed for the experimental groups were supplemented with vermiculite: (A experimental group) a basal diet (BD) without vermiculite (V), (B) 97% of BD supplemented 3% V, (C) BD supplemented with 5% V, (D) 97% BD+3% V+ fish meal (1% V and 2% FM) and (E) 95% basal diet and 5% V+ fish meal (1.5% V and 3.5% FM) (Table 1). The feed additives where the vermiculite with fishmeal is the concentration, showed good results during storage compared with other relations.
Feeding, weight control and maintenance of the hens was according to management guide leading for "Hajseks white". The vermiculite used in this study was provided by LLP «Kulantau» (Kazakhstan), brand M-150, fraction was 0.5-3.0 mm. Treatments were assigned randomly and consisted of the incorporation vermiculite in commercial ingredients of diets. The vermiculite is characterized by high Fe2O3 content (20.59%); SiO2 (17.8%); K2O (8.18%); Al2O3 (7.22%); MgO
(6.4%); TiO2 (2.27%); CaO (1.79%) and FeO (0.56%) (data unpublished). The approximate dimensions of the crystals used in obtaining the diffraction data were 0.4×0.2×0.2 mm.
METHODS
Egg production and morphometric parameters of eggs
The intensity of an eggs production of laying hens was determined as a ratio of number egg laid in experimental period and expressed as a percentage and was monitored for 8 weeks. Morphometric parameters of eggs were investigated at 3th, 6th and 9th week of the experiment. The eggs were weighed, average eggshell thickness was measured. The density was measured by hydrometer. Next, eggs were broken to assess albumen quality using an egg analyzer Sampling method and organoleptic analysis were performed according to GOST procedures (GOST 2009)