Dutch food and chemicals group DSM has agreed to buy privately-held Brazilian animal nutrition company Tortuga for about 465 million euros ($578 million) to strengthen its presence in Latin America, making its fourth big acquisition. DSM, the world’s largest vitamin maker, has sold off its lower-margin bulk chemicals businesses to focus on less cyclical areas including food ingredients and high-end plastics, and has made three other big purchases in the past year and a half. DSM said in a statement it could pay a maximum of 25 million euros extra to the owners of Tortuga if the company’s operating profit came in higher than expected.