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Milk Fever
[Low calcium = Hypocalcaemia]:
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Grass contains a high level of calcium.
If a "soon to calve" cow eats a generous amount of LUSH grass.
-
It can "cause" her
"calcium mobilizing
mechanisms" to become "LAZY".
The result:
When her body NEEDS CALCIUM
URGENTLY: her body/system is unable to cope.
(Around calving there is a great demand for calcium in her body: The
calf, "making" colostrum, and later milk production.)
-Just prior to calving, and up to a fortnight after calving are the
"danger" times for milk fever.
This is more so for a dairy cow being milked out twice a day..
It's not necessarily the highest producer either.
More jersey cows will come down with milk fever than Fresians.
Milk fever is rare in 1st calvers.
Possibly there is an inherited predisposition to milk fever...(Make a
note of your cattle that have metabolic problems. If their daughters
also have
problems, then there may be merit in NOT breeding/keeping female
offspring.)
When
she's given a low calcium diet:
She can cope with demands because her calcium metabolising mechanisms have been
"primed".
There
are other factors that can also predispose her to milk fever:
-Pasture plants with low magnesium content.-
This is particularly so in NZ,
as farmers tend to calve cows
very early in spring.
Early spring in most parts of NZ is chilly!! The ground temperatures
fall below 7 degrees Celsius. (Below 7 degrees many pasture plants
(especially clover) will NOT grow. Clover is a great source of magnesium.
-High potassium levels in the soil :
Can trigger milk fever..
Dairy farmers, and farmers wanting rapid pasture production use fertilizers to
boost pasture production.
(Soil testing reassures farmers that their potassium levels are not too high.)
-However a lot of potassium is passed in urine..
Problems have been known to occur when farmers continually use paddocks close to the milking parlour as over night paddocks..
This does save traipsing from "the back of the farm"
in the early hours of the morning. Cow's excrete the nutrients
they've consumed in those faraway paddocks.. and it will elevate the potassium
level. (Referred to as fertility transfer)
Lush pastures produces a high intestinal pH, thus
it depresses calcium and magnesium absorption.
Cows which have had milk fever are often slower at getting back in calf.
* *
Sunny weather.. Sunshine (& hay) does provide the cow with VIT D..
and Vit D assists with calcium metabolizing. |
How
to minimize the chances of milk fever occurring:
-Don't
let your in calf cows
graze lush pastures in the last three weeks of their pregnancy.
-Feed
a "maintenance diet" to your incalf cows.. With a ration of grass also feed her hay.
Hay does contain
some Vit D.
Sunshine does make farmers happy at calving.. There is usually less milk fever
in the herd.. Cow's get
their vitamin D through their skin (like we do) from sunlight... and off course
with sunshine there are less puddles, and mud about.
-Provide Magnesium:
Magnesium only stays in her body for a short time. Daily "doses" of magnesium
are needed.
-"Pasture dust" her ration of pasture with a magnesium dust/powder each day.
(available from farm supply stores)
-Add magnesium to her hay.. You can prepare several days of hay rations in
advance.. and it's tasty.
Make a solution of magnesium powder, molasses, and water.. and pour it
over the next several day's rations.
You can "trough treat" Using magnesium designed for water troughs.. This is not
necessarily an accurate way of dosing your pre-calvers.
Some cows will drink more than others.. If the trough is filled with fresh water
it will gradually dilute the magnesium content.
Other methods:
Some farmers administer an injection of Vit D to animals with a history of milk
fever prior to calving.
If your really worried calcium boragluconate can be given subcutaneously around
calving.
If she has a history of milk fever.. consider if it's worthwhile keeping her in
the herd.
Milk
fever in cattle (this is an English website:)
http://www.nadis.org.uk/DiseasesCattle/Milk%20Fever/MILKFE_1.htm
Signs and symptoms
of
MILK FEVER:
Calcium is required to liberate acetylcholine, a chemical substance released from nerve endings to activate muscles (and secretory
glands and other nerve cells). Without calcium the cows muscular activity is affected.
In the early stages the cow will walk stiffly. She will clearly be attempting to maintain her balance.
She may be slightly constipated.
She may be found sitting, unable to rise (her hind legs cannot support her).
She may sitting, and her neck has an S shape (normally she would hold her head to one side).
If untreated, she may roll onto her side thus, this may cause some bloating as rumen gases cannot escape.
What to do:
(for products:
http://www.bomac.co.nz )
She'll be frightened.. her legs don't work
properly.
* *
Getting calcium into her is first priority.
If you find she's down:
Sit her up as much as you can - support with a bale of hay to prevent bloat.
If she is up and walking, head her off to your yards, or wedge her between the gate and the fence (electric fence off first).
Give
Calcium boragluconate
solution either:
Intravenously, or subcutaneously.
*The
solution needs to be warmed to "blood heat" before you administer it.
Giving calcium
solution intravenously:
Think carefully prior to attempting to administer Calcium intravenously..
Giving it subcutaneously is just as successful.. and its a darned sight easier!!
Use the neck vein only.. and it is often awkward to get the cows neck in a handy
position... let alone to find the vein.
Important:
AIR
does
NOT
belong
in blood
!!
Let the warmed solution run down the tubing, then pinch the tubing off when it
drips.. as per the sketch.
Pinching off, or bending the tubing will hold the solution in the tube at the
same level.
Finding
the vein!!
With her head to one side .. You may be lucky enough to find the vein in the
hollow of her neck. (dampen the area with an alcohol solution,
and this may help the vein to show.)
When you've found the vein, insert the needle. If you have it in the vein
there will be several drops of blood.
Without allowing air into the tubing.. connect the tubing to the needle.
NOW
You need to elevate the container to help the solution flow.
BUT CAUTION..
(Read the instructions on the solution container)
This fluid given intravenously must be given slowly..
Timing of the solution must be stretched over 10 minutes at least!!
Too fast and you can kill the cow.
When
you remove the needle, just push down on the injection site until any bleeding
stops.
Read
on and discover how easy it is to administer calcium boragluconate
subcutaneously..
Administering calcium solution
subcutaneously.
Best to buy the solution in the plastic "bag" containers.
 These
are so handy, and they'll fit easily in a jug or similar of hot water for
warming.. And they're so quick to administer..
Here are instructions for subcutaneous injections (the results are rapid):
- Elevate the bag or bottle to let the solution flow down the tubing
- Bend the tubing sharply several inches above the needle to stop the flow of fluid.
Air doesn't belong under skin.
Hold the needle with your thumb and 1st finger while firmly keeping the tube
kinked with the rest of your fingers against the palm of your hand.
- With your free hand grasp a clump of her skin (over the ribs)
- Push the needle into her skin, parallel with her body, towards the base of that handful of skin. Then free your hand over the clump of skin
- With a bottle of solution elevate it, and let it drip under the skin. With a bag you may squeeze it to speed up the infusion
- If you wish you can use 2 injection sites to speed up absorption
- Once the solution is under the skin, extract the needle. Rub the infusion site (the bump) vigorously to speed absorption
-
As long as she is in a safe place, take your time.
Go home and make yourself a cup of coffee.
On your return she'll possibly be ready to stand if she's sitting.
Encourage her to do so. (Usually she'll defecate, and that's a good sign that her muscles are 'back to normal').
If she has been 'down for some time' there may be some merit in giving (subutaneously) a calcium, magnesium phosphorous, and glucose solution
.
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Some cows 'sulk' and don't attempt to get up.
Get a few of her herdmates over (peer pressure). They sniff, and Moooo, and may nudge her.
Failing that, it's hip clamps, or the sling, a tractor plus forks on a front end loader.
The idea is to use the sling or clamp to get her standing, to get her to take her weight, to get her walking, while the sling or clamp either take her full weight, or are very slightly slackened off so they can support her if she falls.
She may respond rapidly (including a massive effort as tractor, front end up, forks and sling rapidly move towards her!)
But you may have to consider if all the effort is worthwhile.
While she is standing or sitting, have water and grass handy for her to eat.
Transit tetany:
Similar to milk fever, and it doesn't always happen with travel. The signs are similar to milk fever.
If mild, give her some oral magnesium. More severe, use a calcium solution subcutaneously.
Preparing cattle for travelling long distances:
You're going to start preparing them several days prior to travelling.
Feed them hay (or more than you normally would).
Use causemag, or similar, and mix with molasses and water. Pour/spray over the hay.
Milk fever in sheep:
Calcium boragluconate is available in 50mls, and 100 ml containers.
Use instructions for administering to calves. |
Grass staggers:
[Low magnesium =Hypomagnesaemia]:
Magnesium is an essential mineral responsible for energy metabolism and protein metabolism.
Incidence - stock who haven't received
Magnesium precalving, cattle with a poor dietary intake. It occurs up to 12 weeks after calving. Cold wet weather, with a high wind chill can 'set off' an animal.
You may just find a dead animal. If the ground around her looks as though there has been a struggle then grass staggers is very likely the diagnosis.
Signs and symptoms:
She may be irritable. Her behaviour may be aggressive. Her movements are 'unusual', or uncoordinated. Her eyes, she may blink a lot, they may appear to be glaring. She may froth at the mouth. If in doubt, even if it's very mild (e.g. blinking a lot), treat.
A fright can sometimes trigger convulsions.
HYPOMAGNESAEMIA
(aka grass staggers)
http://www.nadis.org.uk/DiseasesCattle/Hypomagnesaemia/HYPOMA_1.HTM
How to deal with a hypomagnesaemic animal:
Priorities - injecting magnesium, positioning her so you can treat her, somewhere where she can't damage you, and can't injure herself.
You've made your diagnosis. Magnesium solution must be warmed. Ideally, the solution bag and tubing is set up so inserting the needle is all that is needed.
If a yard is very handy get the gates open or shut ready to move her. If the yard is not handy try wedging her between the gate and the fence
(a rope may come in handy). Turn any nearby electric fence off. You've got to move her very very quietly. A fright can trigger convulsions.
The aim is to have her on the fence side of the gate. You should work in the safety at the other side of the gate.
If convulsions don't happen, you betcha, she won't be a cooperative animal! I suggested a rope. Use it behind her, linking the gate and fence.
You've got to work very quickly.
Administer the magnesium as instructions for calcium. Squeeze the bag, get the solution in as soon as possible.
Ketosis/Acetonaemia/'Sleepy sickness':
Up close, the breath of affected animals smell like acetone (nail polish remover).
These animals may be anorexic and lethargic, in fact,
sleepy sickness describes it well.
In brief, animals who are acetonaemic just can't ingest enough energy.
They must use their body reserves.
In goats, in an over-fat nanny, and pregnant with two or more very rapidly growing kids/foeti, it may be simply impossible for her to eat enough.
In cows, (rarely) in an over-fat, newly calved cow. More frequently in high producing dairy cow in early lactation where she just can't eat enough.
In sheep, it is called pregnancy toxaemia. It is quite common. Can occur in the weeks prior to lambing.
Reduced quality or amount of feed can trigger the symptoms (dullness, anorexia, staggering, twitching of ears, face).
Ketosis in sheep can eventuate in blindness.
A preparation is available from the vets or a farm supplies retail store.
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