Thursday, April 22, 2021

Is this problem “management” or “genetics” ?


CONCEPTIONS  Beef cow-calf newsletter                         May-June 2020

While we are generally familiar with lethal gene recessives (eg, the THC and PHAC conditions that float through Shorthorn and Maine-Anjou sires) we are less aware of how to tell when we are dealing with some other genetic weakness.    First, in the case of lethal recessives, calves are either aborted early, are born deformed, or stillborn—and you can see the deformity.     When this happens, you know the sire you used AND your cow you bred are both “carriers”, which warns you on any future breedings to avoid use of carrier bulls on carrier cows.    In the case of sales opportunity for breeding stock, it may even be prudent to consider use “terminal cross” matings on such cows, producing only steers or slaughter heifers.

However, there are lots of other issues where the line is harder to see between a “management” issue you can fix, or a “genetic “ issue that requires compensatory mating to prevent.    How do you tell?     Except with really small herds, the secret is to ask these questions:

“Do all or the majority of cows express this problem?”    If you say YES then you face a management problem; if you say NO then you are seeing a genetic issue.

Management of cow fertility

The quality of fertility in your herd has three focuses:   (1)   genetics—did I select breeding stock from easy breeding cow lines and masculine sire lines?    (2)   herd health—did cows clean quickly and thoroughly after calving, is my vaccination up to date to reduce respiratory interference in the next conception?   (3)   nutrition—do my cows show healthy body condition and strong heats at the time to rebreed?

The latest observer to note the inefficiency of much popular breeding today when it comes to reproduction is Johann Zeitsman (author of “Man, Cattle and Veld”).   In his observation of range cattle in both the Americas and Africa, the test of cow and bull fertility has been rebreeding when on grass, without the “bandaid” of the feedlot grain supplementation.    Even if you do feed grain to promote fast growth on your market and show cattle, it can hide slow fertility character in the momma cows.    Maintaining body condition from high digestibility forages is an indicator of the higher natural fertility cow and seems to give optimal reproduction.

Managing pastures for fertility

“Permanent” (perennial plant varieties) pastures have always been a cost-control input for efficient cow-calf feeding.    The concept developed from England and its culture of developing smaller frame, moderate size breeds on lush pastures, such cattle could breed, calve, nurse a calf to weaning and rebreed without grain.   In the Americas, when the scientists took over, they went to Europe seeking larger frame breeds to get heavier weaning and fed-cattle weights, assuming that it was cost-effective to drylot house and creep feed such cattle for the added gain.    On a “net profit” basis, measuring cattle weight sold per acre utilized, it is hard to see a clear advantage to large frame cattle (except when feed sells at a discount to the cost of raising and harvesting it).    Good, dense grass paddocks feed well.

Whether breeding smaller or larger frame cattle, however, a basis on digestible forages rotated so they can be harvested in their optimal vegetative state helps us maintain competitive growth rates at lower costs, often crossing small-frame cows with good milk to large-frame bulls with good post-weaning rates of gain.    The resulting phenotype from such crosses is often attractive to both club calf and feedlot buyers, representing “hybrid vigor” in the differences between genotypes of cows bred vs bulls used (it is not necessary to crossbreed to get hybrid vigor).

The insemination process

When you only do this once a year, it is easy to be a little rusty at the beginning.   Keep in mind you have these objectives:  (1)  Put daily effort into accurate heat detection, so as to inseminate at the optimal time;  (2)  Thaw and prepare the semen in the correct way, minimizing temperature drops after the gun is loaded;   (3)   Get the breeding gun inside the cow within fifteen minutes after extracting it from your storage tank;   (4)    Pass the AI gun through the cervix just into the uterus, no further, and release the semen (the sperm cells will find their way). 

If you need a copy of the full description, such as I use for breeding training, just call and we will send it.     Here is a drawing of what goes on inside the cow:


The rest of it is up to the cow (and the weather)

Cows can lose embryos any time their body temperatures go too high, so keep the need for water and shade in mind where recently bred cows are eating,

We  are  now  in  the  season    when the cows need to be breeding


A few ideas enclosed to stimulate your thinking and observation as you begin your AI season.     At this point we are still getting shipments from CATTLE VISION every two weeks, so if you need semen to complete your season, call (989) 834- 2661 or tell Gene when you see him on the route recharging your tank.


Mich Livestock Service, Inc         ph (989) 834 2661          For the Best in Bulls”

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