by Elizabeth A. Tomlin
“When we think about why we have so many calf health challenges, it can come down to those first few hours of life,” stated Dairy Specialist Dr. Kimberley Morrill.
Morrill joined with Dr. Fernando Soberon in a presentation for the 2014 Calf Health and Nutrition Conference put on by Cornell Cooperative Extension’s Central New York Dairy and Field Crops Team.
Morrill and Soberon presented updated information concerning the critical importance of colostrum to every newborn calf.
“Growth, production and reproduction,” Soberon stated, “These are the three words you want to think about!”
Soberon explained that good, clean colostrum contains hormones and growth factors, such as IGF-I, IGF-II, insulin, growth hormone, lactoferrin, leptin and relaxin, all affecting the calf’s metabolic development and future health and productivity.
“The hormone relaxin in colostrum has been linked in other species with the development of the uterus,” Soberon said.
This hormone likely affects the future reproductive success of the calf.
“Leptin is a well known regulator of the appetite. All of these hormones and growth factors could be contributing to the increased performance observed later in life.”
Colostrum, the “first milk”, provides the first source of nutrients to newborn calves immediately after birth. Rich with immunoglobulins (Ig) and antibodies, it provides the calf with protection from disease until the time that the calf’s immune system becomes functional.
These antibodies identify and destroy disease causing organisms, or pathogens. Some working in the blood stream destroying bacteria and some attaching to membrane linings, as in the intestine, preventing pathogens from causing disease.
“Colostrum is basically setting the calf up for a lifetime,” Morrill said. “It’s affecting her from the day she is born throughout growth and as a lactating cow, affecting longevity.”
Poor quality colostrum presents a serious problem for calf producers.
“Bacteria and other harmful pathogens are often present in maternal colostrum,” explained Morrill. “It has been well documented that bacteria in colostrum can reduce the efficiency of IgG absorption, increasing the risk of failure of passive transfer in calves.”
Pre-partum care and keeping the cow clean before she calves, will help keep colostrum bacteria free. Colostrum from any cow with mastitis should be discarded and although visual evaluation is not recommended to assure that colostrum is of good quality and bacteria free, you can certainly see if it’s too watery, bloody or contaminated with manure.
Morrill recommends maintaining clean and dry facilities, using dry-off treatments and teat sealant to reduce the risk of infection during the dry period and thoroughly cleaning and drying teats before collecting colostrum.
Bacteria will also pass from dirty hands and/or equipment into the colostrum.
“All equipment should be well cleaned and sanitized. This includes milking equipment, buckets, bottles and esophageal feeders,” instructed Morrill.
After collection, colostrum should be fed or kept covered for protection from other contaminants. Excess should be cooled within an hour of harvesting and frozen flat, in gallon sized, zip-lock bags.
Pooling raw colostrum, or collecting from several cows and storing together in one receptacle, has been found to produce lower IgG scores in test results and is discouraged by the dairy industry.
Colostrum should never be stored in the refrigerator in open containers, where teeming bacteria are sure to contaminate it. “My biggest recommendation is to throw out your refrigerator!” Morrill stated.
Pasteurization of colostrum is an option to assure it is bacteria free, however, this method does require equipment specific to colostrum. Research is continuing on this method.
“Unfortunately there is not a simple on-farm test to determine bacteria levels in colostrum,” Morrill admitted.
An instrument that may be used to estimate the degree of passive transfer in calves is the refractometer. Refractometers are available in hand held models or digital, with the digital models being most expensive. Veterinarians or dairy specialists are able to instruct producers on the proper usage and readings.
The sooner calves are fed colostrum after birth, the more efficiently IgG will be absorbed.
Morrill pointed out that calves begin searching for something to feed on at about an hour after birth and may end up with bacteria in their system before the IgG is there to protect them, causing mortality.
“Timing is critical to a successful colostrum-feeding management program. The ability of a calf’s small intestine to absorb immunoglobulins drops rapidly over the first few hours of life. By 24 hours of age, the ability to absorb immunoglobulins is nearly nonexistent. If a calf has not received any colostrum within 12 hours of birth, it is unlikely to be able to absorb enough antibodies to have adequate immunity. For this reason, a calf should receive the first feeding of colostrum within 1 hour of birth when possible.”
The quantity of colostrum given to the newborn calf, as well as how soon after birth the colostrum is administered, will determine how well the IgG are absorbed and effects on the future health of the calf.
“Next time a calf is born, remember, 4 liters during the first 2 hours of life and another 2 liters within 12 hours and you will be setting her up for success!” stressed Soberon.
He explained that calves who consume insufficient amounts of IgG will not only have inadequate passive transfer, but will lose the potential to achieve optimal future productivity.
Soberon reported on a recent study at Cornell University, which was designed to understand the interaction between colostrum fed at birth and pre-weaning nutrient intake. The results of this study clearly showed evidence that calves receiving 4 liters of colostrum at birth and allowed extra milk replacer had doubled their birth weight by weaning time.
Once you miss that critical window for calves to absorb nutrients and develop, the window closes.
Studies also show that nutrient intake before weaning is consistent with positive effects on future milk yield.
CNY CCE 2014 Calf Health and Nutrition Conference: shaping her future
by Elizabeth A. Tomlin