WHAT IS ARTIFICIAL INSEMINATION?
Artificial Insemination is the process of introducing viable semen (sperm and seminal fluid) into the female reproductive tract without involving direct contact between male and female.
WHY ARTIFICIAL INSEMINATION IS PREFERED?
- It is the best method of changing the animal`s genetic potential in shorter time. It is easier for a farmer keeping indigenous cows to select among exotic bulls for cross breeding his herd to obtain crosses which will survive well and become more productive under the existing environment.
- I is the best way of controlling cattle reproductive diseases such as Brucellosis, Vibriosis, Leptospirosis and Trichomoniasis. These diseases are transmitted by infected bulls during natural mating and causes big economic loss to farmers by causing infertility, abortion and delayed conception
- Costs and risks associated with keeping bulls are avoided.
- Farmers has a wider range to select a bull of interest within and among breeds.
- Fast genetic progress can be realized and a single bull can serve many cows (one bull can produce up to 100,000 doses which can be used even after bull`s death and also there is no need of trekking a cow to find the bull.
WHAT DO I NEED TO BE AWARE OF WHEN USING A.I?
The missing or limiting ingredient in implementing a successful A.I program is often in the area of management. The use of A.I requires a sound management program. When establishing an effective A.I program, a step by step approached may be the best plan of attack. Some of the factors to be considered are:
- Implementation of a sound and efficient record keeping system;
- A sound nutrition program;
- Well-designed, strong cattle handling facilities;
- A sound, effective herd health program;
- Accurate heat detection;
- Aknowledgeable, well trained A.I. Technician.
WHAT IS ESTROUS SYNCHRONIZATION?
Estrous synchronization is simply the manipulation of estrus. It can easily be implemented through industry standardized protocols.
- This allows for a reduction in time and labor, both at the time of insemination and at calving.
- Many calves can be born within just a few days, allowing a producer to concentrate his or her resources into a few days rather than a long calving season.
- This will also increase the uniformity and average weaning weight of offspring, as more calves will be born at the beginning of the calving season.
- The cost of estrus synchronization is relatively minimal when compared to the savings in time and labor, especially in first-calf heifers.
- In spite of this enormous potential to improve production levels, many beef producers have not put themselves in a position to take advantage of the benefits offered by AI.
HOW DO I KNOW, MY COW IS IN HEAT?
She will show the following behaviors changes:
- A cow mount others and stand when mounted.
- Reduces milk when on heat.
- Swelling of the vulva and sticky mucous discharge
- Frequent bellowing
- Reduces feed intake on that particular day.
WHEN SHOULD COWS BE INSEMINATED?
The traditional a.m./p.m. recommendation works best with twice daily observations but may not provide the best conception rates because several cows will be bred too long after the onset of estrus, so the chance for successful fertilization may be missed. The exact onset of estrus is usually unknown. For example, according to the a.m./p.m. guideline, a cow beginningestrus at 1 a.m. and observed in estrus at 6 a.m. would be bred approximately 18 hours after the onset of estrus. Breeding cows at this time would reduce the number of cows that become pregnant. Cows should be inseminated within four to 16 hours of observed estrus when the precise onset of estrus is known.If estrous detection is conducted twice daily, most cows should be within this time period. However, a single mid-morning insemination of cows that have been observed in estrus the same morning or the previous evening should provide acceptable conception rates
HOW SOON AFTER CALVING SHOULD A COW BE BRED BACK AFTER 9 MONTH PREGNANCY?
Let us first discuss the length of time to wait after calving until breeding in a normal 9 month pregnancy, with a normal parturition and passing of placenta.
In almost all of the literature we read, test book, farm magazine, extension services etc., we will find suggestions, wait at least 60 days after calving until we breed the cow back. The artificial breeding organizations have spent years trying to tell the patrons of their services to wait 60 days before calling for service. This interin has become an acceptable fact. Wait at least 60 days. It is sometimes quite a surprise then to learn that if we wish to raise the conception percentage in our herd 10%, if we are following the 60 days plan, all we would need to do is wait 30 more days. A 90 day waiting period after calving will get you a 10% better conception than the suggested 60 days .most dairymen are more interested in having a cow calve every 12-13 months than in showing a high conception rate. So , if we start breeding cows at 60 days after freshening and rebreed all that return in 3 weeks , we will have more cows bred at say 100 days after calving than if wait 90 days, but not near as many will conceive on the first service. So, even though we know we will have less conception on the first service, we still say breed back in 60 days. The reason is that a good percentage of cows are ready to breed at this time. This, of course, is assuming that everything is normal, and that, if not, a longer interval will be necessary, depending on the severity of the abnormal condition.
HOW SOON SHOULD WE BREED A COW BACK AFTER A 7 MONTH ABORTION?
Here we can immediately say, it would depend on what caused the abortion. In diseases like trichomoniasis and vibriosis we know cows need about 90 days more to overcome the infections .The virus abortions may take less time .If the cow cleans normally and no infectious agents are diagnosed, the return of the uterus to normal should be about the same in a 7 month abortion as with a 9 month pregnancy.
WHY CONSIDER CROSS-BREEDING?
A successful cross-breeding strategy can:
- Introduce favourable genes from another breed selected more strongly for traits of interest remove the negative effects associated with inbreeding depression for many traits to capitalise on what is known as heterosis or hybrid vigour (HV).
- HV means that cross-bred animals usually perform better than that expected based on the average of their parents.
- HV is generally higher in traits related to fitness and health i.e. traits which have lower heritabilities.
- Heterosis for production traits is usually in the range of 0 to 5%, whereas heterosis for traits related to fertility is usually in the range 5 to 25%.
ARE THERE ANY DOWNSIDES TO CROSS-BREEDING?
Increased variation: if both parental breeds differ considerably for a given characteristic (e.g. animal size) then considerable variation in this trait can be experienced with multiple crosses.
WHAT IS MEANT BY GENOMIC SELECTION?
- Genomic selection is simply a fancy term for “breeding using DNA”.
- DNA is the backbone of genes which cause differences in performance among animals.
- DNA is passed from parents to offspring and is therefore fundamental to breeding.
- Animals with the best DNA are selected as parents of the next generation.
- DNA is the same in all cells of the body and remains the same throughout life.
- If we know how each piece of DNA effects performance, by taking a DNA sample of a calf, we can predict its performance later in life.
- Genomic selection currently constitutes approximately one-third of the EBI of the animal; the remainder is from the traditional method of genetic evaluation of the parent