If dairy cows were actual wild animals and hadn't been domesticated over 10,000 years ago, they would have a calf once a year, similar to deer or elk, or moose. It may surprise you to know that on a dairy farm, a cow also has a calf once a year.
My cow Norma has reached the point in time in her life where she would like to experience the love of another bovine. Actually since Norma calved back in early August she has had 3 instances of these carnal cravings also known as showing a heat.
A cow completes an estrus cycle about every 21 days. These "episodes" feature her "riding" other cows and allowing cows to ride her. When a cow is in heat they don't care if the animal they are jumping on or being ridden by is devoid of the correct plumbing. These "standing heats" usually last about a day and then she goes back to her normal, "I don't need your bull" existence. On our farm we don't keep a bull around to do the business that needs to get done. Bulls can be unpredictable at best and deadly at worst. Instead we use artificial insemination (AI) to breed our cows.
One of the benefits of using AI to breed your cows is that instead of one or two bulls hanging out with the ladies, you can have multiple boyfriends for your cows hanging out in a tank of liquid nitrogen just waiting for the perfect time to be defrosted and make a baby. This allows you to choose a bull that compliments your cow. By compliment I don't mean that the bull tells her she has a nice "dairy air", I mean that you can pick a bull that can improve on your cows genetics by either offering a quality that your cow needs improvement on or lending more of something good that your cow already has.
Of course these improvements don't actually work on the cow, marrying Julia Roberts certainly didn't make Lyle Lovett hotter. But if they had children at least Julia's genetics would have given them a chance. The right mate for a cow can make the cow's offspring even better than the cow and is one major reason the dairy cows of today make more milk and are healthier than the generations before them.
Anyways, Norma came into "heat" the other day, exactly on her son Ned's 2 month birthday. She had already come into heat twice since he was born and would probably already be pregnant if she was in "nature". But we don't want our cows to become pregnant so soon after calving so we wait a couple of months before we breed them again. She had also been checked out by our vet to make sure that she was ready to carry a calf again.
Now being that Norma is the best cow ever you may think that I could use just about any bull on her and the calf would be a rockstar like it's mother. However the pesky thing about genetics is that it comes from both parents not just one. So I set out on a search to find the perfect bull for Norma. Here is what I knew I wanted in a bullfriend for Norma.
1. I want to use "sexed" semen. Semen is available on some bulls that gives you a 90(ish)% chance to have your cow have a heifer (girl) calf. Because Norma is my favorite and best cow I want her to have a heifer calf to carry on her legacy. On our dairy we sell bull calves because they don't make milk and we are a dairy not a beef operation.
2. I wanted to use a bull that was polled. A polled bull or cow is an animal that has no horns and can pass that genetic trait on to it's offspring. I hate dehorning calves and I think polled is the way to go whenever possible. More dairy cattle breeders are concentrating on breeding great polled cattle and the selection of polled bulls has grown a ton over the last 10 years.
3. I always look for calving ease in bulls. What's calving ease you say? Simple calving ease is a measurment that shows how easy it is going to be for the calf to come out of the cow. I prefer to make it as easy as possible for my cows to calve, bulls with big heads or the tendency to make huge calves need not apply. I bet many mothers of big headed babies can appreciate that.
4. I also want a bull that will compliment Norma's strengths. She has a lot of awesome going on and I am not about to breed her to a bull that isn't as awesome. So beyond what I have already mentioned how much more can I really ask out of a bull? Well thankfully the AI industry has really put their thinking caps on and have come up with a large list of very specific traits that are inheritable by a calf. I can choose for milk production, foot and leg conformation, how much butter fat and protein she will produce, udder depth, height, the ability for the daughters of this mating to be able to easily get in calf (DPR), how susceptible to mastitis the cows will be, overall longevity and loads more options.
For Norma I wanted a bull that would compliment her high butter fat and protein levels, would decrease her udder depth slightly and not take away anything in the milk department. I addition to those specific qualities for Norma I like to use bulls on all of my cows that have high longevity scores and aren't negative on DPR meaning that I would could be breeding a problem with getting pregnant into my cows.
After looking at my options that fit all of my qualifications I picked a Holstein bull, Sellcrest Midas Red-P to breed Norma to. Not only does he match my qualifications pretty well he is also bred by a farm just to the North of our farm. So that adds a little something extra special. Norma will be checked in about 30 days if she doesn't come into heat before then and we are crossing our fingers that she will have a heifer calf in about 9 months.
Angela
I always love reading your blogs!!! Fun, informative and love feeling the passion behind all that you do!
Connie Packard Kamedulski
As a former Animal Science major -- who aced Repro and Genetics back in the day -- I really enjoyed your blog post. Informative, accurate, and simple for the non-aggies to understand.
dairycarrie
Thanks Connie!
Jackie
I like the look of him! Check out dempsy from slect sires. His babies are small smart and friendly. They mvst milk well or the boss would nou use him.
dairycarrie
Dempsy is a good bull but he isn't polled and I try to pick polled bulls first.
Kerry
The range of your puns and euphemisms is impressive! Some questions though...
1. I understood most operations (at least in the west) tend to use sexed semen on heifers only given their likelihood to conceive versus older cows. Is your use of sexed semen on Norma particular to her since you like her, or do you use it widely on all your cows?
2. I have never understood the apparent push back against breeding for polled animals in dairy, particularly considering the labor-saving element of not needing to disbud/dehorn and the fact management practices like that are attracting a lot of negative attention on the animal rights/welfare front. Can you give some insight into why dairymen (and women) seem to have resisted breeding for polled (or correct me if my experience is not representative)?
dairycarrie
Hi Kerry!
Thanks for the comments. To answer your questions...
Yes I used sexed semen on Norma because Norma is a special to me cow and I want daughters from her. I have considered flushing her for embryos so that I could have more of her genetics in my herd but the cost is pretty prohibitive. Sexed semen does have lower fertility because it has fewer sperm cells in it so using it on your most fertile animals, heifers make the most financial sense. Some dairies only use it on their heifers and some use it on the top 10% of their cows, some don't use it at all.
As far as polled genetics goes. Until fairly recently the polled dairy bulls out there just weren't as good as the non polled bulls. The gentic base for the polled genes was small and it takes time to build a good genetic base of animals that are from different lines so that you're not breeding a polled animal to another animal from the same family. Right now there are only a few family lines that carry the polled genes. As breeders focus on these genetics we are able to get further and further out from those original animals and improve the genetic base by bringing in new families.
Jackie
So if you breed m polled bull to a horned heifer what are your chances of a polled calf
dairycarrie
Glad you asked! Polled is actually a dominant gene so breeding a polled bull to a horned heifer you would have a 50% chance of the calf being born polled. There are also Homozygous polled bulls available that have two copies of the dominant gene so 100% of the calves born from those bulls will be born polled no matter the horn status of the mother.
arnikolas
Love posts like this - coming from an anything-but-Ag background it was easy to understand and informative! Thanks Carrie 🙂
dairycarrie
Thanks Angie!
Garoleen Wilson
Are there any undesirable traits associated with the polled gene in dairy cattle, like blue eyed white cats being deaf, the lethal white gene in Overo paint horses and hermaphrodite in polled goats?
dairycarrie
No. In fact most beef breeds are polled.
Weekend Cowgirl (@WeekendCowgirl)
What a great post! We AI, but have a "clean up bull" also for our "beef" cattle... Norma is so pretty!
Sellcrest Farm
Hey! Great choice on the bull!
dairycarrie
Thought you might like him!
Marilyn Torrey Easter
Wouldn't it be great if people chose a mate in a similiar fashion so the next generation hopefully would be an improvement instead of just falling in LOVE!!!!!! Especially when you consider the divorce rate these days. Dairy Carrie your posts are great. Enjoy reading them.