What's the difference between henhouse and penhouse?

Henhouse

Definition:

Example Sentences:

(1) If I were elected president, the foxes would no longer guard the henhouse,” he said.
(2) "When we go down this road of having executive branch insiders continually placed in charge of reviewing the executive branch, it is more of a fox guarding the henhouse situation."
(3) There’s a hungry fox guarding the henhouse at our Environmental Protection Agency,” said Donna Brazile, the interim chair of the Democratic National Committee, in a statement.
(4) Although sister Nancy's claim that Debo could imitate a hen expelling an egg might have been a joke, Debo did drive the cart delivering the Mitford henhouse eggs to the station.
(5) These are the people who watch a wolverine devour a henhouse on Discovery HD and yell at the screen because the chickens “refused to compromise.” Which leaves us with Clinton, who refuses to apologize.
(6) Nigel Farage declared he had unleashed a "Ukip fox in the Westminster henhouse" and continued to predict a victory in the European elections, the results of which are due on Sunday.

Definition:

Example Sentences:

(1) Regression analysis indicated a positive relationship between plasma ascorbate and IgG in metal penhoused calves and a negative relationship in hutch-housed calves.