Monitoring of vitamin‐mineral metabolism’ indicators in cows of different period of lactation

Abstract

The vitamin‐mineral metabolism of cows has an important role in the body’s functional status of productive animals. Lactation cycle is the stress in the body of animals. For this reason the continuous provision by vitamins and minerals of organism is actual and important point. The aim of the study was to research the influence of vitamin‐mineral bolus’ supplmentation with prolong action on vitamin and mineral metabolism of the cows in the different time of lactation cycle. The studies were carried out in one of the breeding farms of the Leningrad region (Russia). Holstein cows were used aged from 3 to 5 years. The milk production of cows was 5625 kg. 5 groups were formed (n=5 by each). The cows of the 1st experimental group have received two boluses All – mineral plus (the compound: Mg, Zn, Cu, Co, Se, I, Vitamin A, D3, E, Holland Animal Care, Holland), 2d experimental group– two boluses Uno Biotin (the compound: Mg, Zn, Cu, Co, Se, I, Vitamin A, D3, E, Holland Animal Care, Holland), 3d experimental group ‐ one Cattle bolus with Iodine (the compound: Cu, Co, Se, I, Telsol Limited, United Kingdom), 4th experimental group – one Cattle Bullet (the compound: Mg, Zn, Cu, Co, Se, I, Vitamin A, D3, E, Holland Animal Care, Holland). The 5th group was control with ordinary ration vitamin‐mineral diet. All cows of experimental groups have got boluses one time which was 60 days before calving. The prolongation of all boluses was 120 days after receiving except bolus All‐mineral plus. The prolongation of their was 180 days. Blood were collected 4 times: 60 days (before bolus’supplementation) before calving, in the dry period (36 days before calving), in the fresh period (7 days after calving) and in the lactation period (81 days after calving). Serum was analyzed for zinc, copper, iodine and carotin. We were used Student's t‐tests to study differences between groups. Thus, we have observed the statistically increasing of copper’s level in the blood of cows of 1st group in the dry period in 1.7 times (p=0,000479) compared with the data beforebolus’supplementation. The level of zinc was increased in 1.6 times (p=0,000143) in the cows of 1st group in the dry time and in 1.4 times (p=0.039139) in the cows of 2d group in the same time compared with data before bolus’supplementation. The level of iodine was increased by 1.5 in the cows of 1st group in the dry time compared with data beforebolus’supplementation. There was 5,00±0,20 mcg %. The carotin’s level increased in 3.4 times (p=0,003647) in the cows of 1st group in the dry period and in 3.9 times (p=0,012621) in the fresh period compared with data before bolus’supplementation. This point was statistically increased in 1.4 times (p=0,049364) in the cows of 2d group in the dry period and it was 2,71±0,18 mg %. So, we can assume that the supplementation of vitamin‐mineral boluses with prolongation by 180 days has a positive influence on the vitamin and mineral metabolism of cows in the dry and fresh periods.