A disorder mainly affecting dairy cows on the brink of calving, Milk Fever is a metabolic disease caused by low blood calcium levels. It commonly occurs in the first few days of a cow starting its lactation period, with the demand for calcium for milk production exceeding any calcium reserves in a cow.
Milk Fever can lead to a number of problems in a cow down the line, such as a reduction in milk yields, calving difficulties, displaced abomasum’s, ketosis, mastitis, metritis, a decrease in fertility, retained cleanings and more.
There are three stages of the disease, the first of which cows only show minor symptoms, such as tremors, restlessness, ear twitching, head bobbing and mild forms of ataxia. In this stage, cows are still mobile, but very excitable.
If left untreated the animal will then move onto stage two, where cows are no longer able to stand up. Here they show weakened heart contractions and appear dull, with lower than normal body temperatures. Some animals begin to suffer from bloat, whilst unable to excrete urine and defecate.
In the final stage of the disease (Stage 3), cows show lateral recumbency, muscle flaccidity and are generally unresponsive, sometimes going unconscious or into a coma. A lack of treatment in this stage will almost certainly end in death. An average of one in twenty cows affected will die from Milk Fever, with surviving cows suffering a reduction in production.
As mentioned, Milk Fever is caused by cows not having enough Calcium in their system upon commencing their lactation period, leading to weakness and even death in some cases.
Higher producing cows are most susceptible to milk fever, with most symptoms showing up within 72-hours of calving. Older cows, on their 5th-6th calves, are much more susceptible than heifers or first-time calvers. In fact, heifers are rarely affected.
One good way of preventing milk fever in your livestock is by ensuring your feed is meeting the nutritional requirements of your cows.
Ensuring the body condition score of your animals is at optimal levels (3-3.25 )prior to calving is very important in preventing milk fever as heavier animals are at a greater risk of getting milk fever than lighter cows. Grazing cows on clover-dominant pastures will also provide your stock with more than enough calcium.
“Fat cows are four times more likely to develop milk fever” Dairygoldagri state.
Feeding hay before calving and reducing greens fed to stock will make the blood acidic and in turn, help improve a cow’s calcium absorption. It is also advised to feed dry cow minerals, which contain high traces of magnesium, while any forage crops being fed should have low levels of potassium.
As is always the case, vigilance is key when treating your livestock for milk fever. The early it is detected the better and the more likely your animal will survive.
Once detected, treatment should be provided ASAP. The main way of treating milk fever is via calcium injections. Once the disease is detected early enough and cows have been treated, there is no reason why they cannot fully recover.