Cows can be very aggressive, especially when establishing a pecking order, so you need to watch how new and especially pregnant animals are integrated into an established herd. Two cows fighting can result in a cow losing the calf because of the direct hits to the belly by the other cow’s head; a cow slipping on ice and losing her calf or breaking her own hip; or a timid cow being pushed off feed and losing weight and not milking as well. All these situations have a negative effect on your pocket book and your state of mind.
There are ways you can gradually introduce the new cows heavy in calf into the established herd. In an ideal situation you would keep the new cows separate from the herd until they were calved out and doing well with their new calves. This isn’t usually a practical option especially when it comes to calving time and you need every space possible for cows with their young calves. But you can try is a gradual integration. You might be able to start by putting the heavy cows or heifers in with your yearling replacement heifers. Sheer size should help heavy animals from being bullied or pushed off feed. The young girls will be curious, but they are not usually too aggressive.
This will give you a chance to get to know your new animals, and for them to get used to you and your operation. Give them a few days or even a week or more to acclimatize to the new environment. After they are comfortable with you and your feeding program, you can move them out with the main herd of cows. A good time is after you have given your main herd a partial feeding. While the cows are out working on their breakfast you can turn the new girls into the field and let them get used to things. Its important they know where the water is, too. Perhaps feed them close to the watering system, making sure they don’t get boxed in by an aggressive cow.
The main herd will be curious to check out the newcomers. Make sure the herd can meet the new animals in an open space where one cow can’t get a new cow in a corner and hurt her. With space the new cow can move away from an aggressive cow, instead of being cornered and forced to fight.
After the introduction go back out and feed the rest of the feed but feed it away from the earlier feeding. Any timid animals will be able to eat away from the main herd and gradually integrate into the herd without going hungry. Particularly with first-calf heifers, make sure the older cows aren’t pushing them off feed. The first-calf heifer requires more feed because she is trying to put that into her calf and herself. She’s still growing whereas the older cows aren’t. Make sure you are putting out enough feed to accommodate the first calf heifers.
As the animals get use to each other, they are not as likely to be aggressive. The old cows may still butt a younger cow with her head to get her to move away from choice feed, but they are less likely to stand and fight with each other.
It also helps to put out bedding when you feed, or at least make sure that the bedding stays fresh. This will draw the old cow to fill up on hay and then seek a nice place to lay down and chew her cud.
By feeding the cows in an open space, in a couple different places, and making sure that the cows have fresh bedding near by will hopefully reduce conflicts. So good luck at the sales and don’t worry about brining home cows or heifers heavy in calf, they will fit in with your herd in time.