ALBION — Under a gray sky threatening rain, farmer Brendan Holmes toured Misty Brook Farm, followed by an entourage of staffers for Maine’s elected representatives, bureaucrats and the news media. Holmes, his wife, Katia, and their sons Johnny and Alister took the group of about a dozen people through the barns where they keep their hogs and calves, into the milking shed, and down into the fields to meet the dairy and beef cattle, sheep and free-range chickens. The cause of the tour was a visit to the farm by Val Dolcini, the administrator of the Farm Service Agency, a wing of the federal Department of Agriculture. Dolcini was capping off a weeklong tour of New England farms, with visits to Massachusetts, Vermont and New Hampshire, and touting the benefits of the 2014 Farm Bill. The bill includes new programs such as micro-loans and low-cost crop insurance aimed at helping young farmers start businesses.