The Evaluation of efficiency of different mineral additives on milk yield and quality in dairy cows

Abstract

Introduction Scientific and technological progress in agriculture is of great importance to the performance of livestock. Higher milk yields, better quality of milk, higher gains and increased fertility rates are related with nutrition. A well balanced diet is one of the main factors affecting the health of livestock. A lot of trace elements supplements of various chemical compositions are created to improve performance of livestock. Various researchers (Griffiths et al., 2007; Karkoodi et al., 2012; Krys et al., 2009; Weiss et al., 2010) have tried to find out how trace minerals supplements impact on animal performance. The results have been diverse. This indicates that all factors, which are affecting the nutritional needs of organisms, are not fully understood. Therefore, the aim of our study was to evaluate the efficiency of different trace mineral additives on cows’ milk yield and milk quality. Materials and Methods The experiment was carried out with cows in the dairy farm of Kaišiadoriai. Sixty clinically healthy cows were selected for the investigation taking into consideration time of calving, nutrition and state of health. The experimental cows were divided into three groups, of 20 cows each. Cows in the first groups were fed a ration with inorganic mineral additives (IMA), which was made from calcium, magnesium and potassium chlorides, sodium dihydrogen phosphate, cobalt carbonate, copper, zinc and manganese sulphates, potassium iodide, sodium selenite. The cows of the second group received a complexed mineral additive (CMA), which was made from inorganic (magnesium and potassium chlorides, sodium dihydrogencarbonate, manganese sulphate, potassium iodide and sodium selenite) and organic (zinc, copper and cobalt gluconates, and potassium lactate) salts. The last group –constituted the Control cows, which did not receive any mineral additives, only licks of sodium chloride. Tested minerals supplements w were fed to the IMA and CMA cows every other day for 3 months at levels indicated in Table 1. Samples of milk were taken once every month, during control milking. Amount of milk yield (kg/d), fats, proteins, lactose and somatic cell counts (SCC) in milk were determined once every month. Milk yield was measured on farm, and the indicators of composition and SCC were determined in the laboratory of ‘Pieno tyrimai’, by use of a Lacto Scope FTIR (FT1.0.2001) and Soma Scope (CA-3A4, 2004), respectively. Subclinical mastitis was detected by using the California Mastitis Test (CMT). Results and Discussion Treatment groups IMA and CMA produced more milk (4.84% and 6%, respectively) compared to the control cows. Cows, which received CMA, also produced more milk (1.25%), compared with cows in the IMA group (Fig. 1.).Milk fat contents of IMA, CMA and control cows ranged from 3.72 – 4.3%, 3.55 – 4.1% and 3.79 – 4.11%. Milk fat of IMA and CMA cows tended to