The top after-market Nasdaq gainers Thursday were Acme Packet Inc, Frequency Electronics Inc, AngioDynamics Inc, Celldex Therapeutics Inc and Resources Connection Inc.

The top after-market Nasdaq losers were Power-One Inc, Horizon Pharma Inc, Tractor Supply Company, ARIAD Pharmaceutical Inc and Perficient Inc.

Gainers

Acme Packet Inc (APKT) shares climbed 6.34 percent to $ 16.60 in after-hours trading. Phone and data network equipment manufacturer Thursday said that it will buy back up to $200 million in stock over the next 12 months.

Shares of Frequency Electronics Inc (FEIM) rose 5.10 percent in post-market session to close at $8.25. The company reported a 20 percent year-over-year increase in revenues to $63.6 million for the fiscal year ended April 30, 2012, as compared to the revenues of $53.2 million for the fiscal 2011.   

Company's operating profit for fiscal 2012 almost doubled to $6.9 million as compared to the operating profit of $3.5 million for fiscal 2011.

AngioDynamics Inc (ANGO) shares advanced 5.06 percent to $11.84 in post-market trading. The company reported fourth quarter EPS of $0.10 against the consensus estimate of $0.09 per share.

The company reported revenues of $57.7 million for the quarter against the consensus estimate of $52.97 million.  

Celldex Therapeutics Inc (CLDX) shares gained 5.01 percent and reached $ 5.45 in after-hours trading. Celldex stocks have a 52-week low of $2.05, a 52-week high of $5.72 and $304.84 million in market capitalization.   

Resources Connection Inc (RECN) shares surged 4.27 percent to $12.20 in after-hours trading Thursday. The outsourcing and advisory company reported Thursday fiscal fourth-quarter profit which showed a jump of 65 percent. The company reported an EPS of $0.21, better than the analysts' estimate of $0.15.

Losers

Power-One Inc (PWER) slumped 3.37 percent to $4.30 in the post-market session Thursday.  The stocks have a 52-week low of $3.51, a 52-week high of $7.90 and $542.74 million in market capitalization.     

Horizon Pharma Inc (HZNP) shares plunged 2.51 percent to $ 6.98 in post-market session. The company shares have a 52-week low of $3.05, a 52-week high of $9.34 and $241.32 million in market capitalization.   

Tractor Supply Company (TSCO) shares lost 2.84 percent in after-hours trading to reach $80.50. The company shares have a 52-week low of $49.02, a 52-week high of $101.20 and $5.97 billion in market capitalization.

ARIAD Pharmaceutical Inc (ARIA) shares dropped 2.05 percent to $ 17.03 in after-hours trading.  Shares of the biopharmaceutical company have a 52-week low of $7.55, a 52-week high of $18.33 and $2.88 billion in market capitalization.

Perficient Inc (PRFT) shares declined 1.92 percent to $11.75 in after-hours trading. The information technology consulting firm's shares have a 52-week low of $6.41, a 52-week high of $12.95 and 382.64 million in market capitalization.