OK, I should have been more careful about citing that other article which claimed "ketosis" is limited to humans and ruminants. Actually, it was really propaganda attempting (ONCE AGAIN) to paint ketosis in humans as somehow bad or a pathological condition which it isn't.
The case of cows is totally, totally different. First of all, it only affects females. Unlike human ketosis, it is an illness and leads to health complications or even death. At first I thought OK, maybe this is bovine ketoacidosis but no, their acid does not go up. So what gives? Again, this is unique only to bovines and only to the female - and probably related to centuries of breeding and husbandry to make a creature which produces an abnormally large amount of milk. It is only triggered during the peak of milk production when there is a large demand for glucose and it must be glucose - ketones cannot stand in.
Here's a technical description followed by a less technical one:
Bovine ketosis requires the combination of intense adipose mobilization and a high glucose demand. Both of these conditions are present in early lactation, at which time negative energy balance leads to adipose mobilization and milk synthesis creates a high glucose demand. Adipose mobilization is accompanied by high blood serum concentrations of nonesterified fatty acids (NEFA). During periods of intense gluconeogenesis, a large portion of serum NEFA is directed to ketone body synthesis in the liver. Thus, the clinicopathologic characterization of ketosis includes high serum concentrations of NEFA and ketone bodies and low concentrations of glucose. In contrast to many other species, cattle with hyperketonemia do not have concurrent acidemia. The serum ketone bodies are acetone, acetoacetate, and β-hydroxybutyrate (BHB).
Did you get all that?? I made it through the second sentence. While it is good to have such detailed articles explaining the unexplainable, I also like to have the ‘to the point’ lesson. The best explanation of Ketosis I ever heard is as follows. “During freshening, a cow goes through a great deal of stress and uses an extreme amount of energy. Then milk production kicks into gear, resulting in more energy requirements. If the animal is unable to consume and utilize enough energy to meet these demands, she is experiencing a negative energy balance and will come down with ketosis.” If you like analogies, think of it this way: you burn 3 face cord of wood a week and only cut 1 a week to replace it, what’s going to happen?? A cold winter!! That is why we cut and stack wood to last not days but seasons. The same concept can be used in preventing animal health problems such as Ketosis; increase your animals’ feed intakes and energy levels prior to calving to prevent a big fall.
This most certainly does not happen in humans nor anything remotely resembling it.
This unhealthy form of "ketosis" is limited to domesticated cows and is not similar to states with the same name anywhere else. Ketosis in all other creatures is a normal, healthy and non-threatening state. Ketoacidosis (high fat mobilization along with extremely high blood sugar) is of course dangerous but has nothing to do with ketosis and is more or less its opposite.
Bovine "ketosis:
- very high fat mobilization and FFAs in the blood
- very high demand for and utilization of glucose (for milk production specifically)
- low blood sugar
- NO excess acidity in the blood (so not at all like human ketoacidosis)
- overall energy deficit
- harmful to overall health
Human ketosis:
- normal blood sugars
- low (but sufficient because of low need) insulin
- very low demand for and use of glucose (because cells have switched to ketones)
- a healthy condition, no adverse affects on health
Human ketoacidosis:
- very high blood sugar, never under 220 and rare under 300
- very low (and grossly insufficient) insulin
- inability to utilize glucose (because of lack of insulin and/or insulin resistance)
- a dangerous condition which typically spirals out of control quickly and can be fatal.
