SNP leader and Scottish First Minister Alex Salmond congratulated Mr McDonald on a "fantastic SNP win", adding he would be a "first-class representative for the people of Donside".
Midway into our second term of government and we have comfortably retained a seat which Labour once held. Their failure to make significant progress is a major setback. This is a very bad result for Labour - after six years of opposition, they show no sign of being anything more than an opposition party.
I am also delighted that UKIP failed to retain their deposit. They have never saved a single deposit in Scotland, which once again demonstrates a clear divergence between Scottish and Westminster politics.
First Minister Alex Salmond will set out his case for why Scotland would be better off if it was independent from Britain in his speech at the SNP spring conference today.
The event comes just two days after he said that voters in Scotland will decide the country's future in an independence referendum to be held on September 18 2014.
Mr Salmond promised the conference would "set out the 'why of independence' to the people - what won't happen in an independent Scotland will be getting dragged into illegal wars, having Trident nuclear weapons dumped on the Clyde for another 50 years, or the imposition of bedroom taxes.
"And what will happen will be the mobilisation of the human and natural resources of Scotland to build a prosperous economy and just society."
Independence would "provide Scotland with the opportunity to capture and deliver faster sustainable economic growth, with greater opportunities to tackle key challenges in sustainability and inequality over the long-term", according to a report by The Fiscal Commission Working Group.
It described Scotland as a "wealthy country" which is "on a par with many other successful independent countries".
The panel of experts highlighted a number of key strengths in the Scottish economy, including the energy sector, life sciences, food and drink and tourism.
But it said the country faced a number of challenges "not least tackling the long-term growth gap between Scotland and other comparable countries".
It is clear that over the long-term, Scotland has not completely fulfilled its economic potential.