Posted by Dr. Sara Barber on June 26 2009 09:28
What is ketosis?
Ketosis is a metabolic problem in dairy cows where they are utilizing body fat for energy because they are not consuming enough energy. When the body uses fat for energy, ketones are released into the bloodstream and the cow uses these for energy. Too many ketones decrease appetite and will lead to a build-up of fat in the liver. Fat in the liver impairs liver function. Cows will normally drop their feed intake a few days before and after calving. At this time a cow will normally be slightly ketotic.
What cows are more prone to ketosis?
Ketosis generally occurs in cows from freshening to 6 weeks postcalving. Cows on low-energy diets and over-conditioned cows are more likely to develop ketosis. Ketosis can be primary or secondary. Primary ketosis is when the cow develops ketosis with no other disease. Secondary ketosis can occur when a cow has reduced feed intake from a retained placenta, dystocia, mastitis, metritis, milk fever, or lameness.
What are the symptoms of ketosis?
Ketosis can be clinical and subclinical. Cows that have clinical ketosis will be off-feed, weak, and may show nervous symptoms. Cows with subclinical ketosis often do not show any signs of disease. Both forms are associated with reduced milk production and reduced reproductive efficiency.
How do I diagnose ketosis?
Ketosis can be diagnosed by using Ketostik or KetoCheck Powders. KetoStiks are used on urine and turn purple when there are ketones in the urine. KetoCheck powders can be used on milk or urine to detect ketones.
All fresh cows should be monitored closely for appetite for the first two weeks of lactation. All cows should be checked for ketones during the first 10 days of lactation to pick up a subclinical problem before it gets severe.
Why do some cows get ketotic?View Image
All cows are in a negative energy balance for the first 4-6 weeks of lactation. These cows are at risk for ketosis. Cows that get ketotic have decreased feed intake or are eating feed that is low in energy.
What other problems are more prevalent in ketotic cows?
Cows which are ketotic often have other medical problems such as milk fever, mastitis, metritis, displaced abomasums, lameness, or pneumonia. When you examine a sick cow be sure to check for ketones. Treating ketosis in these animals will improve their recovery from other problems.
How do I treat ketosis?
There are several components to ketosis treatment which are important for a successful recovery. First is providing immediate energy to the cow. This is accomplished by giving 500 cc of Dextrose 50% IV. Giving more than 500 cc at one time is not useful because the cow will not absorb it. The second component of treatment is to provide energy precursors for the liver to make more glucose. Give propylene glycol orally at a dose of 200 cc twice a day. Propylene glycol is toxic in large amounts so do not exceed 400 cc per day. The third treatment which can be helpful is one dose of dexamethasone (one cc per cwt IV or IM). The dexamethasone will stimulate the liver to produce more glucose. The fourth area to address is to determine if there are underlying factors which caused decreased feed intake and correct these factors. Things to look for include mastitis, metritis, displaced abomasum, pneumonia, or lameness.
What is fatty liver and how is it related to ketosis?
Fatty liver occurs when a cow is mobilizing too much body fat and cannot utilize that fat for energy. This excess fat is stored in the liver and impairs liver function. Cows with fatty liver have decreased appetites and lose large amounts of weight. Animals with clinical fatty liver symptoms will be ketotic but not all ketotic animals have fatty liver. Fatty liver is difficult to treat because of the slow recovery time. Treatment is the same as for ketosis; dextrose, propylene glycol, and dexamethasone. However, often these cows need to be given dextrose every day and be encouraged to eat by offering a palatable diet and reducing competition at the feedbunk.
The best treatment for fatty liver is prevention. Preventing fatty liver starts pre-calving. Remove all factors which reduce feed intake pre-calving. These factors may include inavailability of feed, crowding, inadequate bunk space, poor feed quality, environmental stress, or heat stress. There is data supporting the use of rumen-protected choline in the transition ration to help prevent fatty liver and ketosis. A choline product we have had good luck with is Reashure.
How can I prevent ketosis?
Remember that ketosis is prevented by maximizing feed intake. Start recording which cows and when in lactation ketosis is occurring. A normal level of ketosis is 5-7%. Talk with your veterinarian and nutritionist on where feed intake problems may be occurring. Remember that if intakes are adequate that the energy level in the ration may be low. Utilizing a transition ration is very helpful in reducing ketosis problems. It is helpful to drench fresh cows with propylene glycol twice a day for the first three days if you are having problems with post-partum ketosis. Drenching fresh cows with FreshStart is also helpful in ketosis prevention and stimulating appetite.