Cal-Maine Foods swung to a fiscal fourth-quarter loss as sales tumbled, hurt by historically low egg prices. The egg producer and distributor on Wednesday posted a loss of $35.9 million, compared with a profit of $342.5 million in last year's comparable quarter.

On a per-share basis, the loss came out to 76 cents, compared with analyst views for earnings of 8 cents, according to FactSet. Sales fell 50% to $552.6 million and missed Wall Street models for $563.8 million.

Chief Executive Sherman Miller said Cal-Maine faced a particularly challenging quarter, as oversupply drove egg prices to historically low inflation-adjusted levels. The average selling price per dozen of conventional eggs decreased more than 70% during the period.