Gildan Activewear Inc.’s earnings rose 25.8 percent in the first quarter, to $61.4 million, as sales grew 17.4 percent to $383.2 million. The bottom line benefited from higher net selling prices for activewear and growth in activewear. Sales of activewear and underwear climbed 25.3 percent to $342.4 million while sales of socks were $40.8 million, down 23.9 percent from last year.