Why is Algeria the #2 milk powder importer in the world?
Four-fifths of Algeria is just desert --which leaves no room for agriculture.  The Algerian economy is mostly powered just by the oil industry, which contribute about ~70% of government revenues. Oil and oil related products constitute more than 80% of Algeria's exports. 

For example, Turkey has twice the population of Algeria but it has more than 7.5 times the cattle Algeria has. (14.2 in Turkey vs 1.6 in Algeria). So the short answer is that Algeria isn't just suited for Agriculture.