Current Progressive Dairy digital edition
Advertisement

0609 PD: Manage your calf health through nutrition

Jud Heinrichs Published on 09 April 2009

Calf health as reflected in morbidity and mortality is a consistent and major issue facing the dairy farmer. Data from the USDA-NAHMS studies clearly show that dairy calf mortality remains above 8 percent year after year, representing a significant economic impact on the dairy farm economy. In addition, morbidity remains high, which adds to the economic burden through added labor and health supply costs. More than 50 percent of this morbidity is related to neonatal scours.

When calf health is discussed, we must begin with the nutrition of the dam and the related influence on the body tissues of the calf at birth. Research has shown that various aspects related to dry cow nutrition can affect the calf at birth. Most notably, minerals fed to dry cows such as selenium (Se), copper (Cu) and zinc (Zn) can greatly influence the calf at birth as well as the colostrum levels of these nutrients. Health issues related to anemia and white-muscle disease that were once common problems in newborn calves in the U.S. are rarely a problem now in well-managed farms due to dietary supplementation of the dry cow. Injections of Se and vitamin E are rarely used today as they are not necessary because of diet supplementation.

advertisement

advertisement

An important calf health issue that also must be covered is colostrum management. There are many clear research publications showing the significant effects of timing, quality and quantity of colostrum fed and its impacts on morbidity, mortality, growth, age at calving and culling of dairy heifers. Failure of passive transfer (FPT) of maternal immunoglobulins through colostrum occurs in a high percentage of calves in the U.S. and other countries because of the way colostrum feeding is managed on dairy farms. The correlation with mortality is very strong, and this, along with morbidity, represents a serious economic loss to dairy farmers.

Recent studies show that colostrum as fed on dairy farms often is not adequate in immunoglobulin and nutrient levels and is often high in bacteria, all of which need to be improved with management on the farm. Methods to increase immunoglobulin levels in colostrum are limited due to the genetics of the cow (dam) and physiological conditions of the cow at calving time. Farmers need to use the tools that we have available to improve colostrum management, namely using a colostrometer and measuring blood protein at 24 to 48 hours to check for and validate passive antibody transfer.

Calf nutrition related to basic feeding also can be addressed in relation to health. Levels of nutrients and types of feeding systems impact health. Both low and high levels of milk/milk replacer feeding have been shown to impact calf health and growth. Feeding with less than 10 percent of bodyweight per day of liquid feed will result in low rates of bodyweight gain, and in situations with added stress, they may predispose calves to increased morbidity. Altering diet nutrient levels have not been shown to affect immunity unless the nutrient levels are extremely low or high, or in the case of low levels, they can be confounded by protein quality. Calves fed very high levels of milk replacer have less digestible protein sources during the first two to three weeks of life, are more predisposed to scouring and reduced growth and likely have reduced immune function.

Dietary supplements have been shown to impact calf health. In a non-antibiotic situation, many supplements have been tried with minimal success. Oligosaccharides are one class of compounds that have been shown to positively affect calf health by reducing the incidence and severity of diarrhea in calves. These supplements need to be fed in the milk replacer or milk daily and have been proven to have a variety of direct impacts in the small intestine and surrounding tissues, thereby reducing the colonization of scours-inducing bacteria.

More recently, nucleotides have been used in neonate milk replacers for many species including calves with great success. In calves it has been shown that added nucleotides, which are considered semi-essential nutrients in young animals, increase small intestinal DNA content, significantly increase abundance of nucleotide transporter mRNA, improve small intestine villi size and improve microbial populations in the gut. In effect, by increasing the dietary level of these nutrients, the young animal will absorb more nutrients in a healthier gut and be healthier overall.

advertisement

Feeding high levels of milk/milk replacer have also shown increased diarrhea and mortality in some cases. In addition, either extreme low or high levels of liquid feeding have been shown to affect dry calf starter (grain/concentrate) intake and thus rumen development. Therefore, it has always been my recommendation to use moderate levels of liquid feeding to keep the calf healthy and growing some, but not to limit dry matter intake from calf starter.

In many respects, rumen development has one of the largest impacts on calf health. As the rumen and its bacterial population develops, the calf begins to rely more on the high-quality microbial protein produced in the rumen and the additional energy produced by volatile fatty acids (VFAs) that these bacteria produce.

It is widely known that prior to weaning, calf morbidity and mortality attributed to diarrhea is great, yet by post-weaning, both situations are greatly reduced. Once the calf is weaned, all feeds have to pass through the rumen first, not using the esophageal groove and bypassing the rumen, and any bacteria that may cause diarrhea must now make it through the rumen bacterial population before they can colonize in the gut. Weaning age can therefore have a large impact on health of the calf and should be minimized when appropriate. Basing weaning age on grain intake is still appropriate. Tradition is not a good reason to use for weaning age.

Nutrition has a many effects on the health of the calf, and improvements must be considered to reduce the high incidence of morbidity and mortality as found on dairy farms. Colostrum management and diet of the dry cow and calf can affect the newborn calf and its health to a great extent. PD

Jud Heinrichs
Dairy Science
Pennsylvania State University

advertisement

LATEST BLOG

LATEST NEWS