Post-weaned dairy calves endure a considerable amount of stress during the move into group housing. Multiple stressors – a new environment, diet change, social adjustments, even transportation – all combine to weaken the calf’s natural defense system. At the same time, commingling with other calves increases pathogen exposure and encourages disease-causing organisms to flourish. This combination of reduced immunity at a time of larger pathogen loads allows respiratory disease-causing bacteria to penetrate the calf’s natural defenses and causes clinical pneumonia. In fact, respiratory disease is the cause of almost half of all heifer deaths after weaning.

There are probably as many ways to raise dairy replacements as there are people raising dairy replacements. Most of these methods are successful; however, everyone knows that some are more successful than others. At the most recent ADSA meetings in Denver last summer, we presented an evaluation of data we have collected to determine what impacts growth of neonatal calves through eight weeks old.

Ask a student about colostrum, and the response will be passive immunity. That’s correct, but it is only part of the story with respect to the biological activity of colostrum. Colostrum is the first milk produced by the mammary gland prior to parturition. This first milk is rich in immunoglobulins (proteins) as well as other chemical constituents and cells that impact the health of the newborn calf. At birth the calf is very susceptible to disease because in cattle there is little, if any, placental transfer of antibodies, in contrast to humans where placental transfer of antibodies from mother to fetus is high.

The Grober Young Animal Development Centre opened its doors in 2009 with the mission of uncovering and presenting best rearing practices for young animals. Over the past two years, approximately 160 calves and 40 lambs have resided at the Woodstock facility for the purpose of conducting nutritional and management research. Grober has partnered with others from the industry (feed companies and producers) in order to ensure the research is applicable in today’s farming community.

Calf health, as reflected in morbidity and mortality, is a consistent and major issue facing the dairy farmer. Data from Europe and the U.S. clearly show that dairy calf mortality remains above 5 to 8 percent year after year, representing a significant economic impact on the dairy farm economy. Recent data from USDA:NAHMS put pre-weaned calf mortality at 7.8 percent in the U.S. (2007). In addition, morbidity remains high, which adds to the economic burden through added labor and health supply costs; over 50 percent of morbidity is related to neonatal scours.

As dairy farms grow and expand their milking herd numbers, so does the dairy replacement herd. With 8 percent of the total number of cows represented by preweaned calves, the number of calves for operations 500 cows and larger can be a minimum of 40 calves on milk at one time. With more calves to feed as the dairy operations grow, time, labor and facilities devoted to the replacement herd also increases.

Nature designed whole milk as food for baby calves. It contains 3 to 3.4 percent protein, 3.5 to 4.5 percent fat and 12.5 percent total solids. On a dry powder basis, milk contains 24 to 27 percent protein and 28 to 36 percent fat. It seems obvious that calves would grow better when fed whole milk, as it is richer in nutrients than the traditional 20 percent protein:20 percent fat milk replacer powder. So why feed a milk replacer?

A tool to assess the critical points of management and their impact on the welfare of calves and heifers was recently developed by researchers at Laval University, Agriculture and Agri-Food Canada, and Valacta. Their results were published in the Journal of Dairy Science and are summarized below. The development and implementation of these types of assessment tools are a critical counter-balance to the legislation approach to animal welfare that groups such as the Humane Society of the U.S. employed recently in California and Ohio.