Online grocer Ocado is continuing its recent surge to head the risers of the FTSE 250. The share price has risen 40 points over the last month and has jumped around 80 points since the start of December. The group, whose main customer is Waitrose, reported a fourth quarter sales increase of 27.4% earlier this month.Southeastern rail franchise operator Go-Ahead has named JD Wetherspoon's Keith Down as its new finance director. Both groups are higher on Monday.Premier Foods, whose most famous brands include Hovis bread and Sharwood's cooking sauces, is lower after selling its vegetarian foods business to a private equity consortium for £205m as it seeks to reduce its debt burden. The £205m price tag is less than the £230m some had reported as Premier's asking price for the division, whose products include those sold under the Quorn brands.Profits are being taken at De La Rue after the banknote printer rejected an improved offer from French rival Oberthur. Oberthur increased its offer for De La Rue to 935p from 905p previously, but De La Rue said that this "continues to undervalue significantly the strong fundamentals of the Company and its long term prospects."FTSE 250 - RisersOcado Group (OCDO) 239.00p +5.29%ITE Group (ITE) 227.70p +4.21%Inchcape (INCH) 391.80p +3.38%Computacenter (CCC) 453.50p +3.26%IG Group Holdings (IGG) 484.40p +3.20%Chemring Group (CHG) 3,342.00p +2.99%Savills (SVS) 349.80p +2.88%ITV (ITV) 77.25p +2.73%FirstGroup (FGP) 389.20p +2.72%Cable & Wireless Worldwide (CW.) 71.75p +2.65%FTSE 250 - FallersHochschild Mining (HOC) 473.40p -3.19%Enterprise Inns (ETI) 106.10p -3.11%Spirent Communications (SPT) 133.40p -2.77%Hikma Pharmaceuticals (HIK) 865.50p -2.70%Senior (SNR) 146.30p -2.66%Premier Foods (PFD) 21.80p -2.46%John Wood Group (WG.) 530.50p -2.39%Telecity Group (TCY) 434.00p -2.38%Sportingbet (SBT) 56.70p -2.24%Moneysupermarket.com Group (MONY) 86.80p -2.14%