Metabolic disease in ruminants 1 + 2 Flashcards
List some causes of ‘post natal depression’ in the dairy cow
Milk fever
RFM / Metritis / Endometritis
Mastitis
Displaced abomasum
Ketosis
Fertility
Lameness
What is milk fever?
Hypocalcaemia ± hypophosphatemia
Which animals are most affected by milk fever?
Dairy cows at/after calving
Increased risk with increasing parity
Why do calcium levels decrease at/after calving?
Due to colostrum/milk demands
Failure to respond to milk fever promptly will lead to the body mobilising what resource?
Calcium from bone
Describe the role of parathyroid hormone in homeostatic calcium control
- Mobilisation of Ca2+ from bone “stores”
- Increased absorption from gut - Requires Mg2+ to function
Describe the role of calcitonin in homeostatic calcium control
Reduces Ca2+ absorption and availability
Describe the role of vitamin D3 in homeostatic calcium control
Increased absorption from gut
Describe the different forms of calcium in the blood
Bound (chiefly to albumin)
Ionised - Ca2+ - active
The ratio of bound and ionised calcium in the blood is dependant on?
pH dependant – reduced binding with reduced blood pH
List the 3 main functions of calcium in the body
Muscle function
Nerve impulses
Immune response
What are the signs of acute milk fever
- Seen at/after calving
- Initial hyper-excitement: tremor, etc
- Recumbent as muscles have stopped working
- Guts/glands stopped working: no faeces, no urination, dry noses, postural bloat
- Slow pulse/HR
List the DDx of a recumbent cow after calving
- Milk fever
- Acute coliform mastitis
- Botulism
- Injury at calving
How does acute coliform mastitis present?
High pulse rate/heart rate
Temp – high/normal/low!
Endotoxaemic – mucous membranes injected
± Diarrhoea
If a cow has milk fever which single treatment should they respond to?
Ca alone
Describe how to treat hypocalcaemia
- I/V Ca Borogluconate 40% (11.9g/400ml) calcium
- HypoCa often complicated by HypoPhos (will do no harm if not hypoP)
- S/C administration of little use as its absorbed too slowly
- Place in sternal recumbency
When administering IV Ca borogluconate what must be considered
Care with rapid infusion - Heart
Hypophosphatemia is most commonly seen with which other deficiency?
Hypocalcaemia
How is hypophosphataemia treated?
- Vigophos solution for injection for cattle (Forte) contains organic phosphorous source, with Vitamin B12 supplementation
- Calciject 40 CM for treating milk fever has 5% magnesium hypophosphite hexahydrate
Sub-clinical hypocalcaemia acts as a risk factor for which other diseases?
- Immunosuppression
- Coliform mastitis
- Metritis/endometritis
- “post-partum depression”
List the prevention strategies for hypocalcaemia at/after calving
“Aim to tone up the parathyroids prior to calving”
- Feed low Ca diet pre-calving
- Feed high Magnesium pre-calving
- Boluses/drench/stomach tube at calving
- Maximise DMI pre-calving
- Forage mineral analysis to determine extent of challenge
What does DCAD stand for?
Dietary cation/anion difference