Is the word arroba the same in Brazilian and European Portuguese?

No

The difference lies in typical usage. In Brazil, "arroba" is a vital, modern unit of measurement used daily in the agribusiness sector to price livestock (cattle) and commodities like soybeans or corn; in this context, one arroba is standardized at 15 kg. In Portugal, "arroba" is an archaic unit that is no longer used in modern commerce or daily life, as Portugal uses the metric system (kilograms) exclusively.

Brazilian Portuguese Examples:

1. "O preço da arroba do boi subiu hoje." (The price of the cattle unit went up today.)
2. "A safra de soja rendeu muitas arrobas por hectare." (The soybean harvest yielded many arrobas per hectare.)
3. "Preciso vender duas arrobas de carne." (I need to sell two arrobas of meat.)
4. "O produtor rural conferiu o peso em arrobas." (The rural producer checked the weight in arrobas.)
5. "A arroba do café está em queda." (The price of the coffee unit is falling.)

Continental Portuguese Examples:

1. "O preço do gado subiu hoje." (The price of cattle went up today.)
2. "A colheita de soja rendeu muitos quilos por hectare." (The soybean harvest yielded many kilos per hectare.)
3. "Preciso vender dois quilos de carne." (I need to sell two kilos of meat.)
4. "O produtor verificou o peso em quilogramas." (The producer verified the weight in kilograms.)
5. "O valor do café está a baixar." (The value of coffee is dropping.)