Pharmweigh designs and manufacturers high quality livestock and agricultural weighing equipment.
Whether weighing cattle, sheep or pigs, aluminium loadcells do not have the same resilience as stainless steel IP68 loadcells. At best they will be IP65.
Other than being softer with no stated overload capacity, they corrode especially if pin size holes appear in the surface which is highly likely if exposed to muck & slurry.
There is a reason why load bars with aluminium load cells are cheaper than stainless steel loadbars.
Find out how loadbars are constructed before committing. Check the IP, Ingress Protection, rating.