The top after-market NYSE gainers Monday were TransAlta, Rogers Communication, Swift Transportation, Just Energy Group and Under Armour. The top after-market NYSE losers were DeVry Inc, Elan Corp, Quicksilver Resources, Encana Corp and Canadian Natural Resources.

Gainers

TransAlta Corp. (TAC) shares surged 4.76 percent to $17.22 in post-market trading. The company stock plunged nearly 5 percent in regular trading.

Rogers Communication, Inc. (RCI) shares surged 3.76 percent to $38.00 in post-market trading. The stock has a 52-week low of $32.27, a 52-week high of $40.58 and $19.22 billion in market capitalization.

Swift Transportation Co. (SWFT) shares advanced 3.14 percent to $8.20 in post-market trading.

Just Energy Group, Inc. (JE) shares advanced 2.52 percent to $11.00 in post-market trading. The company announced Monday its entry into the commercial UK energy market through its subsidiary, Hudson Energy Supply UK Limited.

Under Armour, Inc. (UA) shares rose 1.90 percent to $49.30 in post-market trading. The company is expected to repot second quarter net profit of $0.05 per share on revenues of $359 million Tuesday.

Losers

DeVry Inc. (DV) shares slumped 22.35 percent to $21.40 in post-market trading as its fourth quarter earnings guidance fell short of expectations. The company expects adjusted net profit to be $0.43 to $0.46 per share on revenues of $500 million to $510 million while analysts' expected net income of $0.78 per share on revenues of $516.69 million.

Elan Corp, Plc. (ELN) shares slumped 17.84 percent to $11.10 in post-market trading. The stock has a 52-week low of $8.58, a 52-week high of $15.27 and $7.96 billion in market capitalization.

Quicksilver Resources Inc. (KWK) shares plunged 6.10 percent to $4.52 in post-market trading.

Encana Corp. (ECA) shares declined 5.11 percent to $20.03 in post-market trading. The stock has a 52-week low of $17.02, a 52-week high of $31.30 and $15.54 billion in market capitalization.

Canadian Natural Resources Ltd. (CNQ) shares fell 4.13 percent to $27.09 in post-market trading. The stock has a 52-week low of $25.01, a 52-week high of $44.12 and $31.08 billion in market capitalization.