Stronger than expected first half year results from insurance, savings and investment giant Legal & General help the FTSE 100 gain 22.6 points in early trading to 6,709.

Legal & General (LGEN) is up 2.5% to 270p after reporting a 6% rise in pre-tax profits to £672 million in the six months to the end of June. Thanks to improved bulk annuity sales it generated 11% more cash than it did a year ago at £629 million and hiked its interim dividend by 19% to 3.4p a share.

Sausage skin manufacturer Devro (DVO) sizzles 3.5% higher to 309.13p on well-received interims showing an improved volume performance and a jump in pre-tax profit. The running Play of the Week reports strong demand for its food industry collagen products and provides a positive update on major projects in the US and China, both on track to begin production in 2016.

Spirax-Sarco (SPX) falls 5% to £32.19 as results for the six months to 30 June disappoint. Slowing industrial production in China, Russia and South Africa meant the engineer's end-markets grew just 1% over the last 12 months, putting pressure on revenue, which grew 3% at constant currency, and operating margins, which declined by 0.4 percentage points. Adjusted earnings per share was 60.5p and full year forecasts of 150p look likely to be trimmed on the back of today's numbers.

Irish low-cost carrier Ryanair (RYA) edges 1.2% higher to €12.96 after the Dublin-based airline posts an 11% increase in customers to 10.1 million in July.

Aviation support and aftermarket services specialist BBA Aviation (BBA) slips 2.5% to 293.5p after the group's interims show a 5% drop in revenue to £1.09 billion. Operating profit nudges 3% higher to £130.2 million.

Yet another injection of new money helps to drive up shares in Coal of Africa (CZA:AIM), despite its underlying commodity price being weak. The stock advances 16.7% to 5.02p as Asian investor Yishun stumps up a $10 million loan and agrees to buy £9.4 million worth of shares at a small premium to the current price. The money will help develop the Makhado coal mine in South Africa.

Plans to build a gold mine in Scotland take shape. Scotgold Resources (SGZ:AIM) rises 10.7% to 0.83p after issuing an economic study on is Cononish project. Stockbroker Numis doesn't think much of the document, saying the asset could be tricky to work.

Respiratory disease drug developer Synairgen (SNG:AIM) rises 5.9% to 35.5p on forming a research collaboration with Australia company Pharmaxis (PXS:ASX). The duo intends to develop a treatment for lung disease idiopathic pulmonary fibrosis, which is expected to be a $1.1 billion market by 2017.

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Issue Date: 05 Aug 2015