the disease that the cattle suffered from; did it happen around any particular region?
Yes, North Island Volcanic Plateau of New Zealand
Cobalt
In the early 20th century, during the development of farming on the North Island Volcanic Plateau of New Zealand, cattle suffered from what was termed "bush sickness". It was discovered that the volcanic soils lacked the cobalt salts essential for the cattle food chain.

where is cobalt located on the periodic table UNANSWERABLE is it a metal? It is a chemical element with the symbol Co and atomic number 27 how is it extracted? Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal what role it plays as a biological agent? It is essential to the metabolism of all animals and how it affects the animal? In the early 20th century, cattle suffered from what was termed "bush sickness", it  was discovered that the volcanic soils lacked the cobalt salts essential for the cattle food chain and in general does it also affects the health of human beings? Yes, chronic cobalt ingestion has caused serious health problems at doses far less than the lethal dose.
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Cobalt [SEP] Cobalt deficiency in animals
In the early 20th century, during the development of farming on the North Island Volcanic Plateau of New Zealand, cattle suffered from what was termed "bush sickness". It was discovered that the volcanic soils lacked the cobalt salts essential for the cattle food chain. The "coast disease" of sheep in the Ninety Mile Desert of the Southeast of South Australia in the 1930s was found to originate in nutritional deficiencies of trace elements cobalt and copper. The cobalt deficiency was overcome by the development of "cobalt bullets", dense pellets of cobalt oxide mixed with clay given orally for lodging in the animal's rumen.