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Ketosis
By: "Nutrient Requirements Of Goats - Number 15, 1981, National Academy Press"
About the Author
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Ketosis is a metabolic disorder defined by increased levels of ketone bodies (acetone, betahydroxybutyric acid, and acetoacetic acid) in blood, milk, and urine, and is associated with elevated blood plasma nonesterified fatty acids (NEFA), which are precursors of ketone bodies. Lactation ketosis is observed primarily in high-producing dairy cows and to a lesser extent in dairy goats (Leach, 1971; Mackenzie, 1973; Schultz, 1974; Guss, 1977). Late pregnancy ketosis is encountered in sheep and goats carrying multiple fetuses. Goats appear to be more resistant than cows or ewes to ketosis. Treatment is similar to that for cows: intravenous glucose, glucocorticoid steroids, adrenocorticotrophic hormone (ACTH) injections, oral drenching with sodium propionate, propylene glycol or chloral hydrate.
Experimentally, phlorizin injections in goats have simulated ketosis by causing glucosuria, hypoglycemia, ketonemia, and blood plasma NEFA level increases (Menahan, 1966). Forcing goats to go without food also results in increases of blood NEFA levels, especially in late pregnancy or during lactation. However, the fat depot is the ultimate source of ketosis, and dairy goats appear to lack the fat reserves of cows and other animals, which might explain why ketosis is unusual in goats.
Increased ketogenesis has been produced by infusion of butyric acid into the rumen of goats with phlorizin induced hypoglycemia; the condition was corrected by intravenous injections of glucose or propionate (Menahan, 1966). Most ketogenesis was produced, however, from butyric acid infusion into the rumen in late pregnancy and when the goats were forced to fast.
Diabetes accompanied by elevated blood NEFA levels has also been simulated in goats by the administration of intravenous alloxan (Menahan, 1966). A glucose drain during late multiple pregnancy and heavy lactation is the triggering stimulus to lipolysis and ketogenesis. A feeback effect from ketonemia in the presence of insulin appears to prevent further increases in fat mobilization and may be important to the survival of the animal.
Increased plasma NEFA levels were a more sensitive indicator of undernutrition in goats than blood ketones or blood glucose levels (Radloff, 1964). Growth hormone, epinephrine, glucocorticoid steroids, and ACTH have direct effects on and relationships to blood ketone levels in goats.
About the Authors: The majority of this information was researched from various tests and sources.
"Nutrient Requirements Of Goats - Number 15, 1981, National Academy Press"
Subcommittee on Goat Nutrition
Committee on Animal Nutrition
Board on Agriculture and Renewable Resources
Commission on Natural Resources
National Research Council
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