why in the 5th plague all the animals were killed but in the 7th they were told to shelter the livestock?

and in plague 10 it says more of they're livstock will die? wierd...

In the 5th plague only the field animals died. Hence the house animals, who survived the 5th plague received boils in the 6th plague. After these plagues the animals could be brought out to the fields again. Hence in the 7th plague God killed the animals in the field-that is, the animals that were in the houses during the 5th plague and brought out to the fields after the plague. Those that were brought into the house survived and ironically were used to pursue the Jews after the Exodus.

typical bible reading..you are not supposed to understand it just read it and obey it..