Medycyna Wet. 64 (10), 1252-1255, 2008
Klebaniuk R., Grela E.R.
Effectiveness of various dietary zinc and copper sources in cow nutrition
The objective of the present researches was to evaluate the effect of the varied percentage of zinc and copper protein chelate in a dietary unit on the chosen haematological, biochemical and productive parameters of cows. The experimental factor was the kind of zinc and copper compound in a supplementary mixture where 25% or 50% of zinc and copper in the form of sulfates was replaced with organic compounds (proteinates) of these elements. A total number of 36 HF cows were assigned into three groups, one control (K-0) and two treatment groups (K-25 and K-50), by an analogue method, considering age, lactation and body weight. Milk yield and composition as well as chosen haematological (RBC, Hb, MCV, MCH, MCHC) and biochemical parameters (glucose and total protein concentration) in cow blood were evaluated. The levels of copper and zinc in blood plasma and milk were determined. The content of the organic forms of zinc and copper in dietary units had a beneficial impact on the red blood cell system and Zn and Cu levels in blood plasma. Milk yield was shown to rise by over 10%, and a 30% increase of the zinc level was noted in the milk of cows receiving the experimental mixtures with a 25% or 50% chelate content in the supplementary feed mixtures.
Key words: cow, chelate, copper, zinc