Grain-fed beefers (steers and heifers) are slaughtered around 18 to 24 months of age. Grass-fed beefers are slaughtered around 24 to 28 months of age.
Pretty well any age, really. Bobby calves (those that are a few days old) can be sold for veal (but this is primarily limited to dairy, not beef cattle). Baby beef calves are those that are from 1 to 6 months of age. Beef steers/heifers/bulls can be slaughtered/sold between 6 and 18 months of age, if your purpose is for beef production.
Before the turn of the century (i.e., before the 20th century), Longhorns were the most prevalent, followed by Hereford cattle.
Jersey bull calves are slaughtered for veal. Jersey cows, when they're too old to be productive any more or are culled for productivity reasons, are slaughtered for beef, which is often made into ground beef for hamburger and such. Ultimately, though, Jerseys are not used for meat, but for dairy or milk production.
The name that is applied to meat that comes from a cattle that is over one year old is "beef."
Male dairy calves will be around 5 to 6 months of age before they are slaughtered, and weigh around 500 to 650 lb. Beef cattle that are raised as slaughter (and thus are no longer calves) are typically around 18 to 24 (sometimes 28) months of age when slaughtered, and reach a target finish weight of around 1400 lbs (or have a body frame score of Choice grade). As for cows and bulls, the age and weight varies greatly, depending on breed, age and reasons for them being culled. A cow or bull can be as young as 2 or as old as 20 when they are slaughtered, and can range from 1000 to 2800 lbs when slaughtered.
Holstein is a type of Beef. Holstein cattle traditionally will have a lower fat to lean ratio and the muscle will retain less moisture, making it a little tuffer than traditional feeder cattle. Holstein cattle are a breed of cattle typically used in the dairy business for their large milk production. They are the ones with the familiar black and white splotched look.
Beef cattle usually will live up to about 15 years, however, when used for meat purposes they will live to about 1-2 years old. Dairy producing cattle will live for about 7-10 years depending on the longevity of the animal. Dairy bulls will live for about 14-15 years. Veal calves will live until they are about 2-5 months old.
Beef cattle are fed many different ways depending on how old the cow/calf is. Usually the cheap meat in stores is from dairy cows. But the best meat comes from cattle raised on alfalfa/oat mixture or cattle that are grazed on open range.
A cow can be any age when slaughtered, especially if you are referring to a female bovine that has given birth to a calf. She can be slaughtered at 3 years of age or as old as 20 years of age. If you are using the term "cow" in a very loose manner, typically a "cow" (being a feeder steer or heifer) is usually slaughtered at around 14 to 24 months of age. A calf raised for baby beef can be slaughtered between 5 and 8 months of age, and a calf used for veal can be slaughtered from 2 weeks to 3 months of age.
Good old beef
Cattle are a mammalian species of herbivorous animals with cloven hooves that have a four-chambered stomach. The word "cattle" is a term that refers to more than one bovine or, colloquially speaking, cow. Cattle are domesticated creatures descended from the truly wild Aurochs and have been selectively bred and used by man for meat, milk and draft work since the New Stone Age.
That all depends on which operation you're referring to: dairy or beef. In all operations, none of the calves are killed after they are born. Bull calves in dairy herds only are separated from their dams a day or two after birth and raised on the bottle until they're 3 months old. They're then put on a hot-ration diet to gain weight, then sold and slaughtered as veal calves. All dairy bull calves that are slaughtered as veal are NOT slaughtered as soon as they're born! They are slaughtered when they are around 5 to 6 months of age.In beef herds, male calves get to stay on and with their mothers for 6 to 10 months before they are weaned. Depending on the operation, most of them are castrated when they are young, a couple weeks after they're born, or close to weaning. When they're castrated depends on the producer and when he/she feels it's best to have the calves cut or banded.