LifeStart sat down with Dr. Fernando Soberon, Technical Services Manager for Nutreco, Canada, to discuss the importance of two critical nutritional factors in the lives of young calves: colostrum and an elevated plane of nutrition.
In Part I of our interview, he discusses the basics of both colostrum quantity and quality and upping the level of nutrition for neonates.
LifeStart:Why is colostrum quantity and quality so important for health, growth and production?
Dr. Soberon: For many years we have focused on colostrum in order to provide IgG's to the calves to protect them from disease during the first weeks of life. Even though colostrum is an excellent tool for this, we now know there are many more bioactive factors in colostrum than just IgG's. IgG's will help the calf for 3 to 4 weeks, but there are other factors within the colostrum that have a much more pronounced and prolonged effect such as gut development, protein production and possible uterine development, as well as other developmental changes.
Multiple studies have observed positive effects on growth rates, age at conception, and milk component production during 1st and 2nd lactation for calves that consumed more colostrum. There are a few studies that have shown that calves that only receive 2 litres of colostrum, which is only enough to achieve proper passive transfer of IgG, do not respond as well to nutritional treatments as calves that received 4 litres of colostrum. In those studies, calves that consumed more colostrum grew better and produced more milk even thought they had been fed and managed the same way after colostrum administration. As the health status with both treatments was the same, disease did not explain the difference in performance.
This shows that IgG's are only a part of the positive effect that calves gain with proper and sufficient administration of colostrum. The recommendation is to give as much colostrum as possible. If time allows, a calf should consume 3 litres within the first hour of life, another 2 litres 6 to 8 hours later, and an additional 2 litres at 12 hours of life. If that is not feasible, calves should consume 4 litres within the first 1 to 2 hours of life, and 2 litres at 12 hours. The amount could be reduced for small breeds and twins, but there have not been negative effects of feeding too much colostrum as long as the colostrum is clean and it is properly administered.
The quality of colostrum is still measured by the concentration of IgG's, although this might change in the near future. For now, we can consider good quality colostrum when it contains over 50 mg/ml of IgG. My preferred way of testing is with a refractometer which is a great way to approximate total protein content of colostrum. Look for a brix reading of 22 or above. That said, a producer should never throw out colostrum that tests below that. They can simply use it for 3rd or 4th feedings instead of within the first couple of feedings. The only colostrum that is not worth feeding is contaminated colostrum (from, say, manure) or colostrum that has a high bacteria count due to coming from an infected cow, or because it sat without proper refrigeration or preservatives. The use of potassium sorbate has been very beneficial when colostrum is going to be stored.
LifeStart: Why is upping the quantity and quality of milk being fed so important to achieve better gains in health, growth and production?
Dr. Soberon: There are several reasons why early life growth is beneficial to calves, as with any other mammal. During early life, growth is primarily spurred by protein accretion. During the first weeks of life, the metabolism of calves is reactive to signals from their environment that change the way they process nutrients. During the pre-weaning stage, calves behave as a monogastrics, so the milk they are fed is directly used by the calves and not by the rumen, thereby increasing the feed efficiency of this stage. Most importantly, growth during this early stage has been consistently and positively associated with future performance. Calves that gained more weight in the first 56 days of life, consistently produced more milk during eventual 1st and 2nd lactations. The relationship between growth and future production shows a linear increase, meaning that the greater the growth pre-weaning the greater the production. So far, there has neither been a plateau nor a maximum growth point.
It is important to note that the growth that shows these positive effects is structural growth. Therefore, sufficient digestible protein is essential to achieve the desired performance. During the first weeks of life, calves are limited in what they can consume due to size. Few calves will consume more than 6 to 7 litres during the first 2 weeks. So, during these weeks, it is important to have protein concentrations of 26% or more. Once the calves are consuming 10 or more litres of milk, the protein concentration could be lower since the requirements are in total grams of protein intake, and not of a specific percentage. If calves are not limited in the amount they can consume, calves within a group will have different growth rates and weaning weights, which might generate problems later in life especially if there is competition among calves. Therefore, it is recommended to limit calves to no more than 1.5 kg of dry matter per day, whether they are consuming milk or milk replacer. Calves should not be weaned before 63 days old. Grain intake prior to weaning is an important measurement to assure a successful transition from acting as a monogastric to being a ruminant.