* Bids for Big Sky will be accepted until Dec. 28
* Regulator finds no grounds to prevent sale to Olymel
WINNIPEG, Manitoba Dec 19 (Reuters) - Canada's second-biggest hog farm, Big Sky Farms, remains up for sale to the highest bidder, with several parties interested although the country's Competition Bureau cleared the way this week for a sale to Quebec meat processor Olymel LP.
The Competition Bureau said on Monday there were no competition issues that would prevent Olymel's C$65-million ($66 million) offer for Big Sky from going ahead.
Big Sky entered receivership in September after piling up C$69 million in debt to secured creditors. Soaring costs of feeding its hogs had left the company unable to pay its bills.
In addition to Olymel, other parties remain interested in buying Big Sky, and a sales process may still head to auction in January, said Kevin Brennan, senior vice-president of the receiver for Big Sky at Ernst & Young.
"The Competition Bureau announcement with respect to Olymel is strictly a procedural matter," Brennan said. "It doesn't mean there aren't other interested parties in acquiring Big Sky. There are, and that process continues."
Other companies have until Dec. 28 to submit a higher bid for Big Sky, a 1-million pig operation based near Humboldt, Saskatchewan. If necessary, bidders would participate in an auction for the company on Jan. 8.
The Competition Bureau also approved Maple Leaf Foods' purchase of distressed Canadian hog producer Puratone Corporation for C$42 million.
Soaring grain costs, due to the severe U.S. drought, have caused North American hog farmers incur losses, forcing some to exit the industry.