Interserve rallied after the British building services and construction company reported a 36% rise in first half profit.The group also said it has secured future work worth up to £7.5bn, compared to £6.4bn at the end of 2013.The interim dividend was lifted 10.3% to 7.5p.Chief executive Adrian Ringrose said it was a very good period for Interserve thanks to "robust" performances from our UK support services and construction businesses and "excellent" results in equipment services.British outsourcing company Serco Group edged lower after Numis Securities lowered its rating to 'reduce' from 'hold' and reduced its price target to 295p from 360p."In our opinion, significant risks still exist to short-medium term forecasts (both operationally and from a probable rights issue) and it will take a considerable length of time to stabilise a business that has seen huge staff turnover, and very significant contract attrition, before any sort of recovery can be delivered," the broker said in a note on Wednesday.Numis also lowered its 2014-16 profit forecasts by 4-5%.FTSE 250 - RisersInterserve (IRV) 636.00p +3.75%Drax Group (DRX) 713.00p +3.48%Supergroup (SGP) 1,041.00p +2.97%Cairn Energy (CNE) 176.90p +2.49%Polymetal International (POLY) 519.50p +2.36%ITE Group (ITE) 197.40p +2.28%Rentokil Initial (RTO) 121.40p +2.02%Hochschild Mining (HOC) 153.30p +1.86%Tate & Lyle (TATE) 654.50p +1.63%Xaar (XAR) 550.00p +1.48%FTSE 250 - FallersSerco Group (SRP) 334.90p -5.18%Imagination Technologies Group (IMG) 183.30p -4.08%Keller Group (KLR) 843.00p -3.99%Just Eat (JE.) 207.00p -3.72%Kazakhmys (KAZ) 313.90p -3.56%Ophir Energy (OPHR) 207.40p -3.31%Intermediate Capital Group (ICP) 385.00p -3.31%Telecity Group (TCY) 743.00p -3.19%Renishaw (RSW) 1,703.00p -3.13%Exova Group (EXO) 220.00p -3.08%RD