El estudio técnico y económico de diferentes estrategias de alimentación en el vacuno lechero

There is a great uncertainty in the dairy sector due to the reduction of profit margins by various factors. To balance this reduction of profitability there are strategies such as the formation of feeding lots or the implementation of a program of accelerated growth in the rearing. Regarding the formation of feeding lots, although theoretically they represent an improvement in profitability, it is necessary to move cows in batches, which can lead to a decrease in production or reproductive performance. There is a great controversy in the magnitude of these because they depend on the characteristics of the cows and the environment where they are housed. Due to the lack of certainty in the magnitude of the damages it is difficult to define the best strategy. On the other hand, on the growth rate of the replacement heifers, the studies on needs and optimal rates of growth agree. However, the studies value the benefit of a larger number of replacement heifers and a decrease in rearing time without assessing the greater economic expense of feeding the calves with a more expensive feeding program. The objective of this study is to evaluate the most profitable feeding strategy for lactating cows and heifers in a dairy farm. The simulator of dairy farms developed by the UAB: www.granjadevacas.es was used. For the feeding strategies of cows in production, it was simulated in farms with 3 production potentials (8000, 12000 and 16000 liters per lactation) comparing the grouping by the number of births (primiparous vs multiparous) and the use of a "high diet" and a "low diet" using different criteria for moving cows: DEL or the median of production. The effects on production and reproduction of the lot change, the ration and milk prices were varied. It was observed that the grouping by number of birth is always more profitable and that of doing groups of feeding. The results did not only vary with the magnitude of the productive and reproductive damages, but also varied with the production potential and with the milk price / ration price ratio. In the strategy of feeding the heifers, was compared the traditional growth with accelerated growth. The accelerated growth was the best. As the price of the heifers increased, the profitability of the accelerated growth increased due to the reduction in expenses for the purchase of heifers.