My neighbor has beef cattle and we were talking about this year he has had 2/3 bull calves so far. He said that someone had shown him an article about the results of feeding clover and time of day bred had on the sex of calves. He said that he was skeptical but interested in doing some studies of his own. The results would be great for a small farmer that could control time of day bred. You could choose which cow would have heifer replacement calves and which you would want for bull or steer calves. I wonder if anyone has seen any research done on this simple approach? Maybe an idea for a grant? Tami in WI

-- Tami in WI (windridg@chorus.net), February 09, 2001

Answers

I've heard that some bulls throw more heifer calves, but don't know if that is true or not. I have always thought that it was a 50/50 chance no matter what. Hey, baby alligators are determined by the temp.......so who knows!At least that is what I have heard......

-- Nan (davidl41@ipa.net), February 09, 2001.

The only time you could control time of day mating would be either AI or stall breeding. Out on pasture, they will breed when she is ready and he is handy.

My calving seasons have started out skewed to one sex, but by the end of the calving season have pretty well evened out. I note he said, "...so far."

I don't think there is anything to either of these.

However, there is some research which shows if you supplement feed cows in the evening, your percentage of day births will increase. I tried it one year (fed out hay getting on towards dark) and my percentage of day versus night calvings didn't seem to change.

-- Ken S. in WC TN (scharabo@aol.com), February 09, 2001.

Dairy goat folks have been trying to manipulate this for years. With very little success. You can pretty much figure that in the lifetime of the doe she will have 50 50 boys to girls.

We have been able to get most of our does kidding in the early afternoon, by only feeding them their alfalfa in late evening. I go out just before bed, 11:00 pm or later, and put out their alfalfa. This sends them to bed with a full rumen of roughage which will take quite awhile to cud chew and digest. Usually by morning does who will kid that day will refuse breakfast, and kid by 3 or 4 pm. Vicki

-- Vicki McGaugh TX (vickilonesomedoe@hotmail.com), February 09, 2001.

Also consider if sex determination was possible, all dairy farmers would be doing it as bull calves are a bummer to them unless they want to grow them out as stub bulls.

-- Ken S. in WC TN (scharabo@aol.com), February 10, 2001.

Yes Ken, and we wouldn't have had 16 bucklings and only 1 doeling born this winter!! :( Vicki

-- Vicki McGaugh TX (vickilonesomedoe@hotmail.com), February 10, 2001.

Vicky:

Generally a scientific finding isn't given much credit unless it is repeatable. Was this a one year, luck of the throw of the dice, or something you can do for several years in a row? Statistics say if you throw the dice often enough, runs of a single number will come up; however, over time, all numbers will show up equally. Now, if you have a stud, and his offsprings, which can consistently throw 90% females, then I suspect you have your fortune made.

-- Ken S. in WC TN (scharabo@aol.com), February 10, 2001.

Nothing that you do to the cow will determine anything. Some bulls have a higher percentage of males or females but it is the sperm that determines the sex, nothing with the egg. If you are into certain sexes, look for chromosome sorting, you can get guarenteed a certain sex but you can still have fertillity problems and it's not the cheapest, they also only do it on selected bulls.

Suzanne

-- Suzanne (hugging_calves@yahoo.com), February 13, 2001.