Titus Toet a dairy farmer from Molo has for the last three years grappled with one of his heifer which cannot hold pregnancy. The farmer having implanted semen into the heifer for several periods is now disappointed by the inability of the cow to conceive and has vowed not to spend any extra money in buying more semen with his only option being selling the heifer.
Toet is among several unlucky dairy farmers who have come face to face with infertility among heifers. There are mainly three causes of infertility in heifers’ namely natural or inborn, infectious and functional sub-infertility.
The inborn/natural causes include free martins which is the twin birth of different sex calves (hermaphrodites). Over 90 percent of female freemartin calves are infertile due to being born with undeveloped female reproductive organ and therefore are always infertile. In this case there is no cure with a farmer with affected cow only having the option of culling it from the rest.
Another cause for inborn/natural problem is the white heifer disease. This is the obstruction of the reproductive tract and is a common abnormality with white coat coloured heifers. Depending on the site of the obstruction, fertilization, conception and birth may or may not be possible due to the fact that only one of the uterine horns may be affected. The problem is known to affect less than 5 percent of the total heifers. Similarly in this case, farmers are advised to cull such affected heifers due to infertility.
Infectious infertility is caused by the disturbances in the reproductive function due to infections in the system. The most common infections include inflammation of the uterine lining, pus formation in the uterus, protozoa infection like trichomonasis, brucellosis, fungal and bacterial infections. These conditions may be treated with specific drugs if identified at an early stage of infection. However, they can also be quite stubborn and may cause culling of the infected animal is not treated on time.
There is also infertility caused by functional sub-infertility which may be due to hormonal imbalances causing the following physiological malfunctions; Inactive ovaries, ovarian cysts and prolonged menstrual period.
Infertility in heifers can also be caused by poor management. This include poor heat detection, use of low quality or expired semen, wrong insemination timing, poor herd administration and environmental factors such as poor nutrition and lack of mineral supplementation. Most reproductive problems are caused by poor management and poor nutrition with natural animal factors being responsible for small percentage of the problem.