The Welsh Mountain Sheep can be termed as an umbrella description to describe many of the breeds indigenous to Wales Through breeding and selection over the centuries the Welsh Mountain has developed into many distinct breeds the Balwen Welsh Mountain Sheep being one of these Balwen Welsh Mountain Sheep originate from one small area of Wales the Tywi Valley

Could you correct the punctuation please?
The Welsh Mountain Sheep can be termed as an umbrella description to describe many of the breeds indigenous to Wales. Through breeding and selection over the centuries, the Welsh Mountain has developed into many distinct breeds; the Balwen Welsh Mountain Sheep being one of these. Balwen Welsh Mountain Sheep originate from one small area of Wales: the Tywi Valley.