12 Health Management Flashcards
Two types of rumen acidosis, the differences
Subacute rumen acidosis
- rumen pH 5.2-5.8, decreasing fiber digestion
- no clinical signs
- need to manage
Lactic acidosis (acute)
- caused by sudden increase in rumen fermentaiton
- need to avoid
Slides 5, 6, 7
Normal rumen fermentation, high fiber and sudden grain
What is hypocalcemia? Occurs in… Associated with…
- low blood ionized Ca content
- often occurs immediately after calving for multiparous cows, not primiparous
- associated w many problems during transition period
What is milk fever
- clinical case of hypocalcemia
- blood ionized Ca content is drastically reduced
- causes problems in muscle contractions
Hypocalcemia can cause what other issues? How
- displaced abomasum (muscle does not contract to expel gas, it accumulates and displaces abomasum)
- uterine infection (expelling placenta requires muscle contraction; muscle is weak = retained)
- mastitis (teat sphincter requires muscle tension)
- low feed intake (depression = don’t walk to bunker)
- general ‘depression’
What causes hypocalcemia? When is risk high?
- dairy cows rarely experience real Ca deficiency
- can mobilize Ca from bone
- hypocalcemia caused by DELAYED Ca mobilization
risk high after calving, not during peak lactation or dry period
Why is hypocalcemia common at calvin
Mechanism maintaining calcium homeostasis is ‘sleeping’ at calving, active at peak lactation and dry period
How do we prevent hypocalcemia
Improve capability to maintain Ca homeostasis
Feeding more Ca DOES NOT prevent milk fever
Two methods of preventing hypocalcemia? A con of each
- Limit Ca intake before calving (makes animal “hungry for Ca)
Con: difficult to cause Ca deficiency in dry cows unless you use a Ca-binder supplement. Cows typically fed alfalfa (high in Ca) before calving irl - Decrease dietary cation-anion difference
- minimize dietary K content
- feed anionic salts
- induce milk metabolic acidosis to maintain Ca homeostasis
- Con: reduces feed intake
Two forms of displacement abomasum
Right DA
Left DA (more common)
Physical causes of displaced abomasum
- pregnancy and calving change the abomasum location
- low DMI after calving and less rumen fill
Physiological causes of displaced abomasum
- lack of normal muscle tone (acidosis? hypocalcemia?)
- abomasum stops contracting
- gas accumulation moves the abomasum
Risk factors for displaced abomasum (5)
- parturition (loss of body fill)
- low forage diets (inadequate rumen fill)
- sudden change in diet
- low feed intake
- hypocalcemia (no muscle contraction)
Slide 21
Ketosis and fatty liver
What is fatty liver? It decreases…
Excess fat deposition in the liver (10-35%)
Decreases:
- gluconeogenesis
- ammonia detoxification
- immune responses
