Around 290 jobs are likely to go in two companies following separate announcements today.
Wincanton has said 150 workers at a distribution depot in Blanchardstown, Dublin face redundancy after the loss of a key contract.
The company operates the depot on behalf of Musgrave, which has now decided to supply its stores directly.
Wincanton said it was now entering into a 30-day consultation period with staff and their union, SIPTU.
Musgrave said that it will create 134 new jobs across its own distribution network to cope with the increased volume of business once the Blanchardstown contract ends.
In a statement, Musgrave said it would hire the new employees across its existing distribution depots in Kilcock, Co Kildare, Fonthill in Dublin and in Cork.
"This will ensure the optimum use of the existing distribution network," it said.
Meanwhile, Largo Foods is set to transfer production from its factory in Gweedore, Co Donegal, to Ashbourne, Co Meath, resulting in the loss of 110 full-time and 30 part-time jobs.
The company said it would begin consultations with staff at the plant, and would offer 70 full-time and 30 part-time staff the chance to transfer to Ashbourne.
Largo Foods produces brands such as Hunky Dorys, Tayto and Perri at its production facilities in Ashbourne, Gweedore, and Barnsley in Britain.
Its Ashbourne plant already employs 360 people.
Údarás na Gaeltachta said it was very disappointed by the prospect of job losses in the Gaeltacht area of Donegal.
It said it had supported and worked closely with Largo Foods over the last 18 years and regretted the implications of the proposed move.
An tÚdarás said it would "prioritise its efforts and put in place a strategic marketing drive in a bid to attract new investment and employment opportunities to the Gaoth Dobhair Business Park".