Browsing by Subject "hyvin sulava nurmisäilörehu"

During the lactation cycle of dairy cows, the feeding strategy can influence the milk yield and the animal's welfare. During early lactation in particular, major changes occur in the metabolism of cows. The cow's body condition score at calving affects early lactation period, as fatter cows mobilize their tissue reserves abundantly due to lower dry matter intake and thus more severe negative energy balance. Excessive mobilization of fat tissue stores can manifest as a metabolic disorder called ketosis. The well-being of the cow and successful feeding has a positive effect on the milk yield and thus also on the economic profitability of the farm. The aim of this study was to examine how concentrate feeding of dairy cows should be implemented throughout the lactation, when lower than usual proportion of concentrate is fed (about 35% of diet dry matter). In the feeding trial, the effects of the concentrate feeding schemes on milk yield of cows during the early and late lactation were investigated. The study also investigated the effects of the concentrate feeding model on the cow's energy balance and the change in live weight and body condition score. The study compared feeding a flat rate of concentrate throughout the lactation to distributing concentrate unevenly according to the lactation stage. The research was carried out in the experimental dairy barn of the Natural Resources Institute in Finland in Jokioinen as two different sub-experiments, where cows in the early and late lactation formed their own experimental groups. Both groups consisted of 20 Nordic Red dairy cows. Early lactation cows started the experiment immediately after calving, unlike cows in the late lactation, which started their experiment all at the same time (approx. 213 days after calving). All cows were fed a total mixed ratio with a concentrate content of 25% in dry matter, the concentrate proportion in the whole diet was adjusted in concentrate stations. The experimental groups were randomly divided into two different groups. The concentrate proportion in early lactation cows was 35% or 45% of the total dry matter intake, and 35% or 27% for late lactation cows. Cows in the early lactation were given 2 dl of propylene glycol per day. Timothy-meadow fescue silage from 1st cut with a D-value of 697 g/kg dry matter was used as forage in the diet. The feeding trials lasted eight weeks. During the trials, the milk yield, feed consumption and live weight of the cows were measured daily. The body condition score of all animals were determined at the beginning and end of the experiment. In addition, blood samples were taken from the cows in the early lactation at production weeks 1, 3 and 6 to determine plasma beta-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFA) concentrations. Based on the current study, it was concluded that in a grass silage-based feeding model, it is the best to emphasize the feeding of concentrate at the beginning of lactation and give less concentrate in late lactation. However, there were no health benefits from a higher proportion of concentrate in terms of energy balance at early lactation when compared to a lower rate of concentrate. Emphasis on concentrate distribution at early lactation is more profitable feeding strategy compared to flat concentrate rate due to increased milk yield and financial results. In addition, the lower live weight gain achieved in the end-lactation with lowered concentrate feeding rate has advantages for the cows' next calving and the beginning of the subsequent production period.