Oorsig / Review
• storage area for food substances like glycogen , vitamins ( A , D , K and certain B vitamins ) and minerals ,
• synthesizing of essential substances like vitamin A , albumin , globulin and other plasma proteins .
The disturbance of normal liver function will have a severe impact on the immune status of the body in general and certain organs in particular , i . e .;
• the uterus may become more prone to infection due to a failure of the liver to break down certain hormones ,
• a reduction in the formation of immunoglobulins may generally affect the immune status of the body .
The immediate post partum period is a critical period for the dairy cow and in this period the prevalence of certain conditions is relatively high . The common postpartum diseases of dairy cows are metritis , mastitis , milk fever , displaced abomasum , retained placenta and ketosis . A cow with TYPE II KETOSIS will be more likely to contract one or more of the above mentioned conditions and will usually respond poorly to treatment for the specific condition . Cows with TYPE II KETOSIS also will manifest a reduced breeding efficiency as evidenced by both a prolonged calving to first oestrus period and an increased number of services per conception .
Predisposing factors of type II ketosis
• Poor reproduction Poor reproduction performance results in extended lactations , which gives the cows time to become overconditioned on the lactation ration towards the end of their lactations .
• Obesity During the last half of the lactation period , when the hormonal regulation of lactation still results in cows to be very efficient in their ability to utilise feed , the ration and intake may far exceed the nutritional requirements of the cow . In obese cows there is a greater adipose tissue mass ready to be broken down and this predisposes them to excessive adipose mobilization and a fatty liver . It must also be remembered that fat cows tend to have a reduced feed intake in late gestation and early lactation , which will exacerbate the lipolysis .
• Post partum disease Type II ketosis may occur as either a predisposing cause or as an effect of postpartum disease . It is not always possible to say which came first .
• Diet A sudden change to an inadequate or inferior ration in especially the steam-up period will encourage lipolysis and predispose to type II ketosis .
• Pre- and postpartum stress Will lead to lypolysis ( adrenergic stimulation ) and poor feed intake
Clinical findings of ketosis
Wasting form
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Rapid loss of weight / mobilization of s / c fat |
reserves (“ Woody ” appearance ). |
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Marked drop in production ( milk yield ) over |
2 - 4 days . Inappetance - first refuse grain |
and later may refuse silage and hay . |
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Cow is dull and listless , depressed and |
reluctant to move or eat . |
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Ruminal |
movements |
decreased , |
hollow , |
empty rumen . TPR normal , but Pulse and |
Resp may be marginally increased |
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Faeces are firm ; mild constipation . |
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Ketotic odour of breath and milk ( smells like |
acetone ). |
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Ketone strip test positive in milk and urine |
( ketostix ): good sensitivity and specificity |
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Death occurs rarely . |
Nervous form Seldom encountered . Shivering , depression , staggering gait , walking in circles and head tilt , aimless movements , crossing of legs , head pressing , leaning against wall , partial " blindness ", vigorous licking of skin of the fore limb , chewing and salivation , hyperaesthesia and bellowing .
Secondary ketosis Usually the patient will not show such classic symptoms , therefore a thorough clinical examination is necessary to identify the primary cause and allow rapid therapy thereof .
Manifestations of type II ketosis There is an increase in the prevalence of common peripartum conditions : Mastitis , Metritis , Displaced Abomasum , Ketosis , Foot problems , retained foetal membranes . The response to therapy for the concurrent peripartum conditions is characteristically poor in type II ketosis outbreaks .
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