What are the disadvantages of polyclonal antibodies?

Despite the many advantages that polyclonal antibodies offer, they also have a few disadvantages such as: 

●       Higher chances of cross reactivity due to recognition of multiple epitopes

●       Higher chances of in false positives because of higher cross-reactivity

●       Limited life span of the host animal

●       Antibody response is dependent on the host animal

●       Heterogeneity within the antibody pool results in nonspecific interaction with the antigen

●       Variation from one batch to another as they are produced in different animals at different times

●       Experiments often require multiple control samples to obtain accurate conclusions