Factors Affecting High Mortality Rates of Dairy Replacement Calves and Heifers in the Tropics and Strategies for Their Reduction

Abstract

The tropics is not an ideal location for calf rearing as the high temperatures and humidities introduce many potential disease problems to milk fed calves. In addition, the type of dairy farming (generally poorly resourced small holder farming) and the general lack of awareness of the long term implications of poorly reared stock do not encourage farmers to pay close attention to their calf and heifer rearing systems. Surveys of calf rearing systems in Asia, tropical Africa and South America highlight the high calf and heifer mortalities. A range of 15 to 25% pre-weaning calf mortality is typical on many tropical dairy farms. It is often as high as 50%, indicating very poor calf management. This contrasts with US findings of less than 8% mortality from birth to 6 months while surveys of Australian farmers report only 3% losses. Simple extension programs on farms in Sri Lanka and Kenya have drastically reduced calf mortalities and improved pre-weaning growth rates. Improved management strategies leading to lower calving intervals, higher calving rates, reduced still born and pre-weaned calf mortalities and fewer non pregnant heifers can supply many more dairy herd replacements than currently occurs. Such strategies can increase the number of replacement heifer calves in the herd from 15 to over 35%, thus allowing farmers to increase their herd sizes through natural increases. Simple management procedures such as ensuring adequate intake of good quality colostrum within the first 12 hours of life, housing and good hygiene to minimise disease transfer, providing clean drinking water, developing appropriate feeding protocols to encourage early rumen development and paying closer attention to climate control and animal health can all lead to improved calf vigour and performance. Good record keeping is also important so farmers can more easily identify susceptible calves and quickly treat potential problems.

Genetic and non-genetic parameters of replacement rate component traits in Holstein Friesian cattle

“…After studying the dynamics of Friesian herds in four dairy farms Menjo et al (2009) concluded that 25% of the Holstein Friesian cattle born on the Kenyan large scale farms were lost before reaching to a productive age, indicating the limitations of such animals’ adaptability to the prevailing environmental conditions. Moreover, Moran (2011) reviewed 17 studies documented on mortality of calves in Asia, tropical Africa and south America and summarized that pre-weaning calf mortality ranged from 15 to 25% and often as high as 50%. The main reasons attributed to the death of exotic breeds in these countries were poor adaptation coupled with poor health, feeding and management problems.…”

Factors Associated with Calf Mortality under Field Condition in Saurashtra Region of Gujarat, India

“…However, higher calf mortality (81.09 and 79.97%, respectively) has been reported by Tiwari et al, (2007) and Sreedhar and Sreenivas (2015) in India. Further, calf mortality in tropical climate has been reported to be as high as 50% (Moran, 2011). Mortality of calf could be reduced by proper management practices like adequate colostrum feeding soon after birth, proper hygiene and housing to reduce disease transfer and proper feeding protocols to enhance rumen growth etc (Lorenz et al, 2011;Moran, 2011).…”

“…Further, calf mortality in tropical climate has been reported to be as high as 50% (Moran, 2011). Mortality of calf could be reduced by proper management practices like adequate colostrum feeding soon after birth, proper hygiene and housing to reduce disease transfer and proper feeding protocols to enhance rumen growth etc (Lorenz et al, 2011;Moran, 2011). Although, several authors reported increased calf mortality with increase in herd size in commercial dairy farms in India as well as outside India (Tiwari et al, 2007;Sreedhar and Sreenivas, 2015;Seppä-Lassila et al, 2016), we observed more survival of calf in larger herds (>10 to 23) compared to smaller (1 to 5 animals) or medium (6-10 animals) herds.…”

Selective Value, Quantification and Genetic Parameters of Components of Replacement Traits in Crossbred Cattle

“…21 Moreover, Moran reviewed 17 studies documented on mortality of calves in Asia, tropical Africa and south America and summarized that pre-weaning calf mortality ranged from 15 to 25% and often as high as 50%. 22 This showed that about half of the total cows left the herd each year due to their death or culling.…”