The majority of heifers will already have calved down this spring and it is of prime importance that lameness is avoided, because if they get it once, it may become a recurring problem.
Lameness is a painful condition that can have a severe negative effect on the animal’s productivity and future performance.
A cow or heifer with lameness will lie down more to rest the painful limb, causing them to eat less and less signs of oestrus (heat).
Stress hormones that are released from the pain of lameness can interfere with rumen function and with the endocrine system that regulates the reproductive system.
This subsequently leads to a drop in milk performance and fertility, which means that the heifer will more than likely be marked for culling.
Heifer lameness
It really doesn’t matter whether it’s a heifer, a cow, a bull, or even a bullock that is lame, it is going to affect performance, production, average daily gain, and fertility drastically.
However, it is of particular performance when it comes to heifers as research indicates that one of the biggest risk factors for lameness is a previous episode of lameness. Once lame, it is a lot more likely to become lame again.
When heifers are freshly introduced to the herd and more than likely have the best genetics in the herd, becoming lame will have a severe impact on their overall lifetime performance within the herd.
When a cow or heifer is lame, structural changes occur within the hoof and a new bone can grow on the surface of the pedal bone which leads to the sole of the hoof becoming vulnerable.
The aim should obviously be to prevent lameness altogether, but for heifers, delaying the first episode of lameness for as long as possible is key to life-long hoof health, while maximising overall lifetime performance.
Prevention
Lameness for any animal starts with managing all the environmental risk factors to prevent damage to the hoof, which at this time of the year is going to involve getting laneways in good condition and ensuring roadways are wide enough for the number of cows.
Another thing to ensure that heifers are not shoved or bullied, forcing them to use their hooves to stay upright, is making sure the collecting yard has adequate space of 1.5m2/animal and that there is enough feed space (at least 0.60m/cow).
Early detection and treatment of cows is critical in the spring time, especially for young heifers who are vulnerable to being bullied and shoved around.
Herd assessments should be done when the cows are walking on level, unobstructed walkways that give the observer a clear view.
Locomotion scoring is frequently performed when the cows are leaving the milking parlour, but if a bat latch is out on the paddocks and the cow’s are walking in of their own free-will, then it can be done before milking which may be the best option to save time.
It is important to note that a cow’s hind foot should land in the same place as her front foot, and failure to do this may be an indication of a lameness issue.
Locomotion scoring is a five-point system based on both gait and posture, as follows:
- Normal: The cow is not lame, the back is flat;
- Mildly lame: The back is slightly arched when walking;
- Moderately lame: The back is arched when both standing and walking. The cow walks with short strides in one or more legs;
- Lame: The lame cow can still bear some weight on the affected foot;
- Severely lame: The back is arched, the cow refuses to bear weight on the affected foot and remains recumbent.
Even though many heifers have already calved at this stage and have already joined the main herd, if there are some still springing and yet to calve, introducing these heifers to the main herd before calving may be a good idea.
Within the herd, cows have a particular social structure and something of a hierarchy, which the introduction of new animals can disrupt, leading to aggression and fighting.
When a young heifer is introduced to such an environment, it can lead to her slipping and twisting which causes hoof damage.
It may be too late at this stage, but something to consider for next year is to introduce heifers to the main herd well before calving, so that the social issues can be resolved before calving time.
When a heifer or cow calves, their hooves are at their most vulnerable to damage because of the relaxation of ligaments caused by hormonal changes.
As we know, as heifers calve down they are nervous and quite jittery as it is all a new experience for them and it may take them a while to break into the routine, and so, gentle handling is crucial.
When moving heifers around or getting them in for milking, the aim for any farmer is to minimise any behaviour that may cause harm to the hoof.
Rushing, running, and causing heifers to slip is going to cause lameness and if it is in the lead up to putting cups on her in the parlour, her adrenaline will be pumping and she may be a nightmare to handle.
