Mid-caps were trading slightly higher on Thursday, though weakness in the industrial metals, transport and technology provided a drag on gains.As of 16:00 BST, the FTSE 250 was trading 0.2% higher at 17,674.Jimmy Choo was trading higher after Barclays initiated coverage on the stock with an 'overweight' recommendation and a price target of 208p on expectations of stronger growth than its sector peers.Outsourcer Serco was extending gains made on Wednesday following a strong first-half trading update, as Numis raised its rating on the stock to 'hold'.Synthomer dipped as operating profits in its European and North American divisions tumbled, due to weak demand and higher raw material prices.Hunting declined as it revealed its operating profit plunged in the first half amid a declining rig count and lower oil prices.Miners Evraz, Lonmin and Acacia Mining were trading in the red as metal prices tentatively recovered from a three-day decline. RisersSerco Group (SRP) 131.60p +11.53%BTG (BTG) 684.50p +9.00%Jimmy Choo (CHOO) 170.00p +8.42%Supergroup (SGP) 1,287.00p +4.72%Keller Group (KLR) 1,066.00p +4.20%Ted Baker (TED) 3,037.00p +4.15%Cineworld Group (CINE) 479.20p +3.97%Redrow (RDW) 460.00p +3.86%Drax Group (DRX) 361.50p +3.82%AA (AA.) 383.40p +3.43%FallersEvraz (EVR) 113.10p -8.20%Hunting (HTG) 576.50p -5.49%Zoopla Property Group (WI) (ZPLA) 264.80p -4.75%Lonmin (LMI) 106.70p -4.65%ICAP (IAP) 505.00p -4.63%Homeserve (HSV) 425.00p -3.47%Foxtons Group (FOXT) 229.60p -3.08%Acacia Mining (ACA) 292.90p -2.98%Alent (ALNT) 362.90p -2.66%Grainger (GRI) 223.10p -2.45%