In England and Wales it is called Year 6 and the pupils are usually 10 to 11 years old. Often it is the seventh year of school; the years being called Reception, Year 1, Year 2, Year 3, Year 4, Year 5 and Year 6.
Quick Answer. According to Animals Australia, the natural lifespan of a dairy cow is approximately 20 years. The average lifespan of a beef cow is 15 to 20 months.
Cows are milked for an average of 3-4 years. A cow must have a calf in order to produce milk.Calves are fed milk until they are 8-9 weeks old. Before milking machines were invented in 1894, farmers could only milk about 6 cows per hour. Today, farmers use machines to milk more than 100 cows per hour. Cows are ruminants, which are cud chewing mammals.