VITAMIN K DEFICIENCY Veterinary Medicine - PowerPoint Presentation

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VITAMIN K DEFICIENCY

Veterinary Medicine

Dr. Anil Kumar

Unit-3

Assistant Professor

VCC, BASU, Patna

Vitamin K Deficiency

Vitamin K, a fat-soluble vitamin, is a group of

napthoqunone

compounds that have characteristic

antihemorrhagic

effects

Vitamin K extracted from plant material was named

phylloquinone

or vitamin K1

Vitamin K extracted from bacterial fermentation were named

menaquinones

or vitamin K2

A synthetic form named

menadione

(K3)-simplest form of vitamin K, is  

is

water soluble.

Function:

The liver is the main repository of vitamin K.

Vitamin K is required for the hepatic post-synthetic transformation of several protein clotting factors

It is essential for the post-translational processing of the

prothrombin

group of coagulation factors (Factors II, VII, IX, and X).

Used  as an antidote in poisoning by

dicoumarol

or

warfarin

.

A role in bone metabolism, as well as in the renal

reabsorption of Ca++. 

Ruminant makes this through rumen microbial biosynthesis and absorbed in the small intestine

Horses generally receive sufficient vitamin K from pasture, hay, and intestinal bacteria to meet their needs. 

Dogs receive both 

K

1

 and 

K

2

 in their diets, and cats derive their

quinones

from eating meat.

Etiology:

Fat

malabsorption

associated with inadequate amounts of bile salts (

eg

,

biliary

obstruction)

Lymphangiectasia

Severe villous atrophy may result in vitamin deficiency and

coagulopathy

owing to the lack of production of the functional vitamin K−dependent Factors II, VII, IX, and X

Vitamin K antagonist or by feeding sulfonamides (in

monogastric species)

Mycotoxins

Moldy sweet clover hay/sweet clover disease-lead to

hypoprothrombinemia

, because of

dicumarol

combines with the

proenzyme

to prevent formation of the active enzyme required for the synthesis of

prothrombin

and also interferes with synthesis of factor VII and other coagulation factors.

Warfarin

as a

rodenticide

Insufficient vitamin K in the diet,

Lack of microbial synthesis within the gut

Inadequate intestinal absorption, or inability of the liver to use the available vitamin K.

Note:

Administration of estrogens increases absorption in both male and female animals

The lymphatic system is the major route of transport of absorbed

phylloquinone

from the intestine in mammals but by portal circulation in birds

Clinical Signs:

Ruminants:

Seen only in the presence of a

metabolic antagonist

, such as

dicumarol

from moldy sweet clover.

The

coumarin

derivatives (

dicumarol

) are not active in the fresh plant because they are bound to glycosides, but are active when sweet clover is improperly cured AND leads to sweet clover poisoning or hemorrhagic sweet clover disease

Death from hemorrhage following a minor injury, or even from apparently spontaneous bleeding

Accidental poisoning of animals with

warfarin

(a synthetic

coumarin

used as a rodent poison)

Initial clinical signs may be stiffness and lameness from bleeding into muscles and articulations.

Hematomas,

epistaxis

(nose bleed), or gastrointestinal bleeding

Death may occur suddenly, with little preliminary evidence of disease, and is caused by spontaneous massive hemorrhage or bleeding after injury, surgery, or parturition

DOGS AND CATS:

Accidental intake of

dicumarol

types of rat poison, such as

warfarin

and

diphenadione

(vitamin K antagonist), will result in a hemorrhagic condition in dogs

Clinical signs in dogs include paleness and evidence of slow but persistent bleeding from a number of sites, including gums, bowel, and several injection punctures

Swine:

Increased

prothrombin

and blood-clotting time, internal hemorrhage, and anemia due to blood loss

Newborn pigs may be pale with loss of blood from the umbilical cord

Diagnosis:

Determination of

prothrombin

time

Prolongation of the

prothrombin

time in the absence of liver disease indicates vitamin K deficiency

Measurement of the plasma concentration of one of the vitamin K-dependent clotting factors (Factor-II, VII, IX and X)

A routinely measure circulating

phylloquinone

as a method of evaluating vitamin K status. <0.5

ng

/ml have been associated with impaired clotting functions

Treatment:

Vit

. K1 @1- 2 mg/kg administered intramuscularly /SC (especially in

Dicumarol

poisoning)

Blood transfusion@10ml/Kg BW

Note:

Vitamin K3 should not be used, especially in horses, because it is associated with renal damage

In horses, the recommended dose (

Vitamin K3 )

is 0.5 to 2.5 mg/kg BW IM