Dear Daktari, I am a dairy farmer and recently I lost one of my calves during birth. It was a bad experience since it caught us unawares. Please educate me on calving to avoid such a scenario next time. [Kimani Joseph, Kiambu County]
Sorry for the loss. There are three stages in calving down or parturition. Knowledge of these stages is important because it helps in deciding the kind of intervention needed. The three stages are dilation of the cervix, delivery of the calf, and delivery of the placenta.
First Stage: Dilation of the cervix
This takes a few days. During this stage the pelvic ligaments relax in preparation for the passage of the calf. You will observe thick but clear string of mucus hanging from the vagina and the cow will not eat as much. As this stage gives way to the second stage uterine muscles contraction begins.
Second stage: Delivery of the calf
This is a very important stage. The stage is signaled with the extrusion of the water bag. If it goes on successfully the calf should be out in one to five hours for heifers. For cows, this stage can be as short as 30 minutes. It is during this stage that the cow may need assistant. In a normal birth, the calf’s front feet and nose will come out first. But if you see this and the calf is not out within an hour then it is time to intervene and help deliver the calf. Gently pull the calf using clean and preferably gloved hands. However, if you do not see the front feet and nose, then you are likely staring at an abnormal presentation that will require veterinary intervention and this must be very quick. Any delays can lead to fetal death.
Third stage: Delivery of the afterbirth
In normal cases the placenta should be out within eight to 12 hours following the delivery of the calf. If the placenta is not out after 12 hours, then we talk of retained placenta which comes with many other diseases.
Retained placenta is most associated with dystocia, milk fever (metabolic diseases) and twin births. The commonest observation in retained placenta is discoloured, ultimately fetid membranes hanging from the cow’s vulva. Sometimes the retained membranes may remain within the uterus and not be visible to the farmer but even in this case a foul-smelling discharge will appear a few days later. Cows with retained fetal membranes are at increased risk of developing metritis, ketosis, mastitis, and even abortion in a subsequent pregnancy.
It is for this reason that retained placenta condition is considered during culling of cows. Manual removal of the retained membranes is no longer recommended and is potentially harmful. Untreated cows expel the membranes within two to ten days but will requiring treatment of possible uterine infections. Good animal husbandry is the best way to prevent retained after birth. This will include supply of correct nutrients, particularly minerals like magnesium, and fat-soluble vitamins (Vitamins A, D, E, and K), maximising dry matter intake, maintaining the correct body condition score, and supplying a clean dry environment.
[The writer is a veterinary surgeon and the head of communications at the Food and Agriculture Organisation of the United Nations (FAO) Kenya. The views expressed here are not necessarily those of FAO]