Down cow

Question 1

Causes of downer cow syndrome (broad categories)

Answer 1

• metabolic
• traumatic
• neurological
• toxic

Question 2

What is down cow syndrome?

Answer 2

• inability of cattle to rise and stand for a period of at least 12-24h for undetermined reason
• also caused bovine secondary recumbency
• a cow becomes a downer cow when the initial cause resolves but the cow still doesn’t rise

Question 3

Metabolic causes of down cow syndrome

Answer 3

• unresolved hypocalcaemia (check phosphorous levels too - creeper cows)
• hypomagnesaemia (generally a cause of becoming a down cow, rather than a chronic situation)
• ketosis (beware angry nervous ketosis cow, is the ketosis primary or secondary?)
• hypokalaemia (often give potassium as part of tx, look for muscular fasciculations)
• fatty liver dz (if fatty liver alone has result in a down cow, the prognosis is poor)
• fog fever

Question 4

Fog fever

Answer 4

• autumn time most likely (foggy mornings)
• movement from sparse to lush pasture
• L-Tryptophan in the pasture converted by the rumen to 3-Methylindole
• this is toxic to lungs
• causes Acute Bovine Pulmonary (O)edema and Emphysema (ABPEE)
• cows can get used to L-Tryptophan with a slow introduction
• if suspicious of fog fever but currently only 1 cow down its likely many others are about to go

Question 5

Hypomagnasaemia

Answer 5

= grass staggers
- seen in the spring with a new flush of grass
- seen in the autumn with stale grass
– situation made worse by high potassium and high ammonium fertiliser
– situation improved by more broad leaf, slower growing plants in the sward (clover, chicory)
- cows and sheep don’t store Mg
– require daily dose to top them up
- lots of magnesium goes into milk

Question 6

Grass staggers tx

Answer 6

• true emergency as will die very fast
• IV magnesium will cause cardiac arrest
• can get away with a small amount given really slowly and warmed- in ‘red top’ calcium
• should take 15 mins to administer bottle IV

Question 7

Grass staggers prevention

Answer 7

• by ensuring adequate is in diet
• can supplement water, but beware this reduces palatability of the water
• take other cows off pasture

Question 8

Traumatic causes of downer cows

Answer 8

• sacroiliac luxation
• coxo-femoral luxation
• gastrocnemius rupture
• ^ 3 often a sequel to struggling to stand
• pelvic fracture
• profound anaemia as a result of haemorrhage
• profound foot lameness

Question 9

Neurological causes of downer cows

Answer 9

• obturator paralysis
• bilateral peroneal paralysis
• rarely - lymphosarcoma infiltration into spine (cows rarely live long enough for these to develop)
• BSE

Question 10

Toxic causes of downer cows

Answer 10

• septic metritis
• acute toxic mastitis, usually with a coliform
• tetanus
• botulism

Question 11

Causes of primary recumbency

Answer 11

• 46% dystocia (obturator nerve paralysis, pelvic fractures, tears, haemorrhage, etc)
• 38% milk fever
• 16% other

Question 12

When does it occur?

Answer 12

• 50% occur within 24h of parturition
• can see seasonal variation -> diet when housed and room to move around when calving, so see higher incidence in winter

Question 13

What happens when a cow becomes recumbent?

Answer 13

• weight on muscles
• compartment syndrome (esp in hindlimbs) (occluded blood vessels causing necrosis of the muscles/tissues - as bp not good enough to keep blood flowing to these areas when down)
• may remain bright and alert (can be a good sign in prognosis, if eating nursing becomes easier to achieve)

Question 14

History qs

Answer 14

• when did she calve?
• was it assisted?
• what degree of traction was used?
• calf alive or dead?
• how long has she been down?
• did she stand after calving?
• is she moving around?
• did she go down here or was she moved here?
• how did you move her here?
• has she eaten/drunk/been drenched?
• has she been treated already?
• have you had any others like this?

Question 15

Treat any underlying conditions

Answer 15

• oral fluids +/- additives
• IV treatments - Ca, P, K, Mg? fluids?
• NSAIDs
• injectable vitamin supplements - B12 (appetite stimulant)
• antibiotics
• propylene glycol instead of glucose: rumen bugs will just use glucose and so none will get to the cow
• hobbling
• splints

Question 16

What impact does good nursing care have on downer cows

Answer 16

• increases recovery % massively

Question 17

Likely dx for S-shaped neck flexion

Answer 17

• hypocalcaemia

Question 18

Likely dx for dog sitting

Answer 18

• damaged sciatic nerve

Question 19

Likely dx for uterine prolapse

Answer 19

• often associated with hypocalcaemia

Question 20

Likely dx for legs abducted

Answer 20

• obturator nerve paralysis, hopeless prognosis

Question 21

Factors that affect prognosis

Answer 21

• season: greatest risk = spring > winter > autumn > summer (relatively small changes in risk)
• days recumbent: straight line graph over time
• HR: brady and tachycardia = bad
• RR: tachypnoea (>36bpm) = bad
• temperature: hypothermic and hyperthermic equally bad
• PCV: anaemic = bad
• leukocytes: leukopenia and neutrophilic = bad
• AST: 500-1000U/l = 2.1x risk, over 1000U/l = 6.9x risk
• CK: 10,000-25,000U/l = 1.5x risk, >25,000 = 4.6x risk
• lateral recumbency - pressure on lungs, abdominal organs, muscles of back legs, saliva build up that isn’t being expelled

Question 22

When to consider PTS

Answer 22

• incurable conditions e.g. fractures, tendon ruptures
• lack of response to tx of primary condition within a reasonable time period
• alert down cow becoming non-alert (indicating further complication0
• pain & suffering
• unable to maintain sternal recumbency despite adequate tx
• not willing to eat or drink despite adequate tx
• obvious bed sores or swollen joints/limbs
• insufficient facilities, labour or expertise

Question 23

Salvage procedures

Answer 23

• clay removal *
• perimortem caesarean
• tibial neurectomy *
• teat removal (but have teat cannula that opens it up and allows it to drain, therefore have no need for teat removal)
• emergency slaughter *
• ovary removal
• semen harvesting
• toe amputation

Question 24

Spastic paresis and tibial neurectomy

Answer 24

• progressive hindlimb condition of unknown origin leading to contraction of gastrocnemius muscle and associated tendons
• it will be possible to manually flex the hock without pain
• if seen in older cattle, likely involve spinal lesions
• can treat with a tenotomy, but neurectomy preferred
• most surgeons find it too fiddly to dissect out the relevant bits of the tibial nerve, and so cut the whole thing - this is acceptable
• might help get calf to slaughter/market weight but no bigger, therefore not suitable for breeding, etc

Question 25

Sign of hypophosphataemia

Answer 25

- sat in sternal recumbency, might try to get up but just don't have the muscle strength to - slide on elbows and knees as trying but failing to get up

Question 26

Signs of fog fever

Answer 26

- eyes congested - elbows abducted - snotty nose - seems like bad pneumonia - but not pyrexic

Question 27

Blood tubes

Answer 27

- all haematology from a purple topped tube: EDTA, on most blood machines - all biochem rom a green topped tube: lithium heparin, on most blood machines - Zinc needs a different tube - Copper needs a different bung