The livestock sector contributes 58.55 percent in the agriculture sector. A positive growth of 3.63 percent during 2015-16 associated with 3.99 percent growth during the same period last year. Livestock is an integral part of agriculture sector. Rural people mostly depend for their livelihood. There are several metabolic disorders of dairy breeds. Milk fever is one of the most common and lethal disorder occurring commonly in Pakistan.
In rural areas, livelihood commonly depend on livestock. Specially for reproduction, meat, and milk. There are various metabolic disorders of dairy breeds including milk fever, lactation tetany, ketosis and post-parturient haemoglobinuria. Milk fever is one of the major issues that relates directly with production, reproduction and performance of dairy cattle.
Milk fever is actually not a fever but it is metabolic disorder. In this disease calcium & phosphorus ratio disturb due to dietary deficiency. Soil of Pakistan has a deficiency of macro and micro minerals. This include calcium, phosphorus, sodium, potassium, copper, cobalt, selenium, iron, and zinc. So that, fodder deficiency of minerals disturbs the mineral profile of blood.
Milk fever is a problem of dairy cattle near to calving that occur due to low calcium level in blood profile. Normal calcium level of blood is 11mg/dl in milk fever it decreases to 4mg/dl.
Stages of milk fever
Clinically, milk fever is divided into three stages.
At first stage, cows show some initial exhilaration or a shiver in muscles of the head and limbs. Symptoms are lethargy, muscle fatigue decreased appetite, ataxia, agalatia (no milk production), ruminal stasis, dry muzzle, staring eyes, cold legs and ears, and constipation. The heart beat becomes weaker and faster. The body temperature falls below normal, it may remain for several hours and during this time animal will response to calcium therapy.
At second stage of milk fever, animal become unable to stand. The cattle become drowsy, no tetany and flaccid muscles, muzzle dry, skin and periphery cooled, rectal temperature 97-98 F. Ruminal stasis, constipation, and bloat, appear. The main differentiating sign is turned head toward the Flank.
At third stage the cattle cannot move, pulse cannot be palpated. Lateral at recumbency stage it can not raise jugular vein. This stage can be recovered with emergency situations by calcium borogluconate therapy by injecting intravenous route.
No doubt calcium borogluconate therapy is drug of choice for milk fever. But major drawback of calcium therapy leads to heart arrest and sometimes animal my die on spot.
Death may occur due to excess or inappropriate method of injecting calcium into the body. Giving infusion in direct sunlight separately may directly react with calcium, which can also lead to death. A combination of some drugs such as injection Hepasel (for constipation ), injection oxytetracycline (antibiotic) may also react, and can cause death of animal.
Hence to avoid such threats one should adopt preventive measures to decrease risk of milk fever in dairy cattle.
We should aware of such types of cattle breeds that are high producers having more risk of milk fever. In about 40 to 60 percent of cases within 12 to 24 hours of calving this occur. Because, most of colostrum is milked by milker from rudder that leads to increase chance of milk fever.
Hence one should be careful in selecting the cow breeds in order to avoid milk fever which includes indigenous, Sahiwal and cross breed that is more prone to milk fever.
Before two weeks of parturition, nutritional feeding to dairy cattle is much important. Because it mainly disturbs the calcium level of blood in body of animal. Due to the metabolism of feed, having higher than required calcium quantity will hinder the absorb-ability of intestine as well as the skeleton of bone. This lead to increased chance of milk fever.
Thin cattle have higher chances of milk fever than fatty one. Calcium to phosphorus normal ratio in blood is 1:2. So we need to feed balance diet of calcium and phosphorus. In absence of dietary management, other methods are in practice, but those are not sufficient enough to prevent milk fever.
Administration of vitamin D3 before 2-8 weeks of calving is useful in absorption of calcium. But, it is not advisable during lactation or dry period due to its calcium captivating property which leads to milk fever.
To decrease milk fever chances and to avoid calcium level fall, experts recommend the milking of second and third part of colostrum (first few days milk). Since, colostrum is a rich source of calcium. The administration of calcium chloride within 24 hours of parturition can also decrease the chances of milk fever.
Normally, it occur during third to fourth lactation which is peak production of cattle. Higher chances are during 12 to 24 hours of parturition and occasionally after 6-8 weeks of parturition. To manage metabolic disorder of cattle it is advisable to consult dairy experts.
Milk fever is a common disease but lethal to cattle. This will result in poor performance of cattle including health issues, decrease milk production, affect reproduction system. It may cause dystocia, loss of uterine tone, delay involution of uterus that lead to calving interval. This will lead to economic losses which is a serious concern for livestock industry.
This article is collectively authored by Dr. Rashid Fayaz, Dr. Asghar Abbas, Dr. Rao Zahid Abbas and Dr. Muhammad Usman.