BIOCHEMICAL PROFILE AND ENZYMES ACTIVITY OF HENS BLOOD SERUM UNDER CHANGES OF HEIGHT OF AN ARRANGEMENT OF CAGE BATTERIES

Abstract

In the conditions of industrial poultry farming, the body of hens is constantly exposed to numerous technological stressors, the least studied of which are long-term, which can cause the development of chronic stress. One such technological stressor may be to increase the tier of cage equipment, which is a method of resource conservation in egg poultry and is often used by producers to obtain more eggs from 1 m2 of poultry area. Increasing the level of cage equipment involves the location of the cage in 12 and even 15 tiers, forming 4–5 floors. This allows to increase the concentration of poultry in the poultry house by 4-5 times, compared with 3-tier cage batteries, and 8-10 times – compared to the floor method of keeping. For this livestock in one poultry house can reach 590 thousand hens. However, there are no data on the impact of such a keeping method on the physiological state of hens, and the current rules of VNTP-APK-04.05. for keeping hens in cages designed for 1-3-tier cage batteries. The aim of this work was to study the physiological state of the hen’s body based on the analysis of the biochemical profile and the activity of serum enzymes in their blood depending on the height of the cage batteries. For this purpose, in the conditions of a modern complex for the production of food eggs in one poultry house, 4 groups of hens were formed, each of which was kept on a separate floor-analogue in terms of area and cage equipment. Each floor was equipped with 3-tier cage batteries “Big Dutchman” (Germany), consisting of 1176 cages. It was found that increasing the layering of cage equipment does not have a negative impact on the hen’s body. So, for keeping hens in cages of multilevel cages batteries located on 2-4 floors (4-12 tiers), the biochemical status and activity of their blood serum enzymes were within the physiological norm. In hens kept in cages of the 3rd floor there was an increase, within the physiological norm, aspartate aminotransferase by 7.9%, and in hens of the 2nd floor there was an increase in glucose by 4.6-6.5%, creatinine – by 2.4%, phosphorus by 8.8-9.6%, as well as an increase in the activity of aspartate aminotransferase by 2.2-10.2% and lactate dehydrogenase – by 11.2%. Whereas, when keeping hens in cages of a multi-tiered cage battery on the first floor, there was an increase in glucose levels by 60.5-71.0% (10.9% ˃ of normal), creatinine – by 9.7-12.3% (4.8 % ˃ norm), phosphorus – 82.6–100.0% (23.6% ˃ norm), a decrease in the ratio of calcium and phosphorus by 46.7-50.0% (46.7% ˂ norm), which was confirmed by an increase in alkaline phosphatase activity by 22.3-27.0% (3.4% ˃ normal), as well as an increase in aspartate aminotransferase activity by 3.2-13.8% (1.7% ˃ normal), lactate dehydrogenase – by 48.5-65.1% (10.8% ˃ of normal) and gamma-glutamyltransferase – by 16.4-20.6%. Thus, the main effects of chronic stress caused by keeping hens in the cells of the lower floor of a multi-tiered cage battery are reflected in the biochemical parameters of their serum, namely increased glucose, creatinine, enzyme activity and change of the ratio of calcium and phosphorus.