disorders of energy balance - farm animals Flashcards
1
Q
gluconeogenesis
A
- ruminants have lower blood glucose than other species
- depend on a continual process of gluconeogenesis
- continues in feeding and nonfeeding
2
Q
high forage ration
A
- > 65% acetic acid
- <15% propionic acid
3
Q
high grain ration
A
- <50% acetic acid
- > 25% propionic acid
4
Q
what is the optimal acetate to propionate ratio
A
> 2.2:1
5
Q
what are 3 practical applications of research on gluconeogenesis
A
- bovine ketosis seems related to a shortage of glucose or gluconeogenic precursors
- cows fed a higher proportion of grain seems related to an abundance of propionate for glucose metabolism
- possible that milk production may be limited by the supply of glucose or glucogenic capacity
6
Q
what are the 3 main contributors to making glucose in dairy cows
A
- propionate
- amino acids
- glycerol
- comes from rumen fermentation
7
Q
what happens during peak lactation
energy
A
- negative energy balance
- metabolic tightrope
8
Q
how does insufficient feed intake cause ketosis
A
- insufficient ruminal production of propionic acid
- not enough glucose and cow becomes hypoglycemic
- hypoglycemia signals fatty acid and glycerol mobilization
- fatty acid and glycerol are oxidized to form Acetyl-Co-A
- excess acetyl-co-a from excessive fat mobilization forms ketone bodies
- ketosis
9
Q
ketosis
A
- common disease of adult dairy cattle
- occurs in early lactation
- negative energy balance leads to fat mobilization
- milk production causes high glucose demand
10
Q
what are the symptoms of ketosis
A
- reduced appetite
- depression
- lowered milk production
- elevated ketones in blood and urine
- sweet smell on breath (acetone)
- uncoordinated/aggressive behavior
- neurological ketosis
11
Q
what does propionate form in the krebs cycle thats needed to make glucose
A
oxalo-acetic acid
12
Q
how to treat ketosis
A
- IV 50% dextrose with steroids
- IV metabolic solutions (Ca, P, Mg, glucose)
- propylene glycol orally
- multivitamin injections
- B12 injections
13
Q
how to prevent negative energy balance
A
- feed cow, fiber and grain diet
