STRATEGIES TO REDUCE CALF MORTALITY
M.V. Jithin, V.K. Varun, Ajit K. Singh, Jeny K. John and Naresh Chandra
Department of Veterinary Clinical Complex, College of Veterinary and Animal Sciences, Sardar Vallabhbhai Patel Univerisity of Agriculture and Technology, Meerut, Uttar Pradesh
The survival of calves and their rapid growth is the most important factor responsible for the propagation of the dairy herd. However, in India, a large number of calves die during the first year of life, causing heavy economic loss. Calf mortality is considered to be an index of the general health status of any dairy farm. A five per cent calf mortality rate is acceptable under standard managemental conditions. A 38 per cent reduction in the profit of a livestock farm is reported to a calf mortality of 20 per cent.
Causes of calf mortality can be divided into infectious and noninfectious origin.
Infectious origin:
Bacterial agents:
Escherichia coli and Salmonella typhimurium are the most common causative agents of calf diarrhea. Salmonella infections are most frequent and of great concern to young animals. The organism can affect calves of any age, but usually affects calves that are over 10 days old. The organism invades the mucosa of the small intestine causing damage of the intestine lining. Infected calves shed the organism in feces, urine, saliva, and nasal secretions, which can survive in the environment for months. Calves that are severely affected, do not drink milk or milk/replacer, become severely dehydrated and have a high fever. Faeces are watery and often tinged with blood with death occurring within 12-48 hours after the first signs appear.
- coli affects calves within the first 10-14 days of age, usually within the first week. There are 3 types of infection occurring with the enteric form as most common characterized by diarrhea, dehydration and the calf returns to normal activity. The toxigenic type of E.coli infection is fatal resulting in sudden death of calves without any outward clinical signs. Lastly the septicemic form which mainly affects colostrums deprived calves wherein general systemic infection results.
Viral agents:
Diarrhoea due to Rotavirus and Coronavirus are major causes of calf mortality. Rotaviruses cause diarrhoea in neonatal calves between the ages of 4 and 14 days. It is also possible for younger and older calves to become infected with rotavirus. Calves infected with rotavirus show watery diarrhea that vary in colour from yellow to green. Infected calves become severely depressed and dehydrated.
Coronavirus usually affects calves that are between 4 and 30 days old. Coronavirus infection of the intestine in calves causes profuse watery diarrhoea. Affected calves become dehydrated very quickly and develop a fever and loss of appetite. Incidence of coronavirus in neonatal calf diarrhoea is slightly lower than rotavirus.
Endoparasite:
Coccidiosis has been observed in calves 3 weeks of age and older, usually following stress, poor sanitation, overcrowding or sudden changes of feed. These organisms enter the body through contaminated feed and water. Infection results in decreasing digestion and absorption of feed ingredients. Clinical findings include diarrhoea (often with blood), depression, weight loss, dehydration, but calves will often continue to eat.
Cryptosporidiosis: Cryptosporidia are typically found in calves from 7-21 days of age. Cryptosporidia are often detected in combination with rotavirus, coronavirus and E. coli.
Non-infectious origin:
Improper colostrum feeding:
Adequate colostrum feeding provides essential immunoglobulins to the calf. Absorption of immunoglobulins continues up to 48 hours in calves, but maximum absorption occurs within the first 6-8 hours of life. The maternal antibodies protect the calf during the initial 6 months of its life Compared to hand feeding, suckling is a greater source of absorption of colostral immunoglobulins; therefore, it is generally recommended to allow the calf to suckle its mother for the first two days post-partum. Immunodeficient calves which do not consume adequate colostrum immediately after birth are prone to diarrhoea, pneumonia and other diseases.
Season of birth:
Season has a significant effect on the calf mortality. A report of 40 per cent total deaths on a farm were recorded during winter season (majority between Dec-Feb). Change in climate and severe cold waves results in stress in immunodeficient calves and they become prone to other infections.
Dystocia:
This is a major cause of calf mortality due to stress that occurs on the calf during a difficult birth. However, research has shown that calving difficulty has long term effects on the immune status of the calf.
Sex and birth weight of calf:
Mortality is higher in male than in female neonatal calves, perhaps due to the fact that absorption of colostral immunoglobulins is less in male than female calves. Birth weight of calves also significantly affects mortality. Higher birth weight calves had calving difficulties, whereas low body weight had lesser ability to handle environmental stresses and diseases.
Management factors:
Poor ventilation, overcrowding, inadequate cleaning and disinfection predispose the calves to various diseases. Tympany and milk indigestion also play an active role in the neonatal calf mortality. Calves should be allowed to move freely in open spaces and exposed to sunlight to get sufficient Vitamin D. Naval disinfection and removal of mucous from the mouth and nose reduces clinical affections in calves.
Control Measures:
General management before birth:
The care of calf starts in the womb of animal itself. The maximum growth of calf takes place during the last trimester of pregnancy. So balanced feeding of cow during the last trimester will give birth to a healthy calf and increase in milk production in the subsequent lactation. Feeding of animals during pregnancy with balanced ration
including mineral mixture and vitamins will prevent deficiencies in both the cow and the calf. It will also take care of other associated problems like retention of placenta, lazy calving, dystocia, milk fever, calf death and poor calf health.
Care of calf after birth:
After the birth of the calf, remove the mucous from its nose and mouth and stimulate breathing. Allow the dam to lick her young one soon after birth to induce maternal instinct and help in cleaning and drying of the newborn. Cut the navel cord about 2 inches away from the abdomen with a sterile blade, ligate it and apply strong tincture iodine solution (7%). Feed colostrum at the rate of 10 per cent of body weight per day in divided doses for the first 4-5 days. Provide a clean, dry resting surface for the calf to ensure that its hair coat stays dry. Protect it from exposure to cold surfaces, low air temperatures and sudden temperature changes. Provide at least 6 inches of bedding as a cushion to minimize physical trauma.
Feeding of calves after birth:
Nutrition and management of neonatal calves has a great impact on their later productivity and longevity. It is essential to feed colostrum to the young one immediately after birth in order to ensure development of adequate immunity until it can produce its own antibodies. Colostrum also has a laxative effect and helps to clear meconium from the gut of the calf. It is a good source of vitamins, minerals, protein and energy. It contains 3-5 times more protein the normal milk and 5- 15 times more Vitamin A. At two weeks of age, the calf should be introduced to good quality green fodder and concentrates, as a calf starter. This stimulates the rumen to grow and function properly.
Deworming:
This is one of the most important management practices followed to prevent mortality in calves. Internal parasites in the calf cause diarrhoea, stunted growth, rough skin and a pot belly shaped abdomen. Worms causes huge losses to dairy farmers in terms of feed loss, growth loss and mortality of calves. So it is necessary to deworm the calves at regular intervals. Growing calves also need to be protected from external parasites like lice, ticks, mites etc. by spraying of animals and livestock sheds with ectoparasiticides regularly.
Reference:
https://www.pashudhanpraharee.com/calf-scours-the-biggest-killer-of-calvesprevention-management/
Kochewad S.A.,Singh J.P., Patil V.M , Vikas Kumar and Bhokre S.M. (2013) Calf mortality causes and control measures Indian Farming 62(10): 23–26.
https://www.researchgate.net/publication/317258410_Calf_mortality-causes_and_control_measures
