By: Stephen B. Blezinger
Common sense tells us that when the cow becomes pregnant, some of the nutrients she consumes at that time will be used by the developing calf from the very beginning. If you have never considered this concept n your cattle, consider this; when a woman becomes pregnant one of the first thing her doctor will do is prescribe a prenatal vitamin and mineral supplement, tells her to cease intake of nicotine or alcohol and to begin watching her diet closely to be sure she is eating correctly. While we generally don't have to worry about smoking or drinking in pregnant cattle, we do need to manage their nutritional program carefully.
There is no other point in time in the calf's life where it is growing and gaining (relatively speaking) as from the time of conception through birth. There is no other time in its life when the development of tissues, organs and systems is occurring as rapidly as during the time in utero. And while the volume of nutrients needed as building blocks for this process is very small, at least initially (the first few weeks after conception) access to the specific nutrients necessary is critical. Our ability to provide these nutrients to the cow in an effective manner, in an effort to enhance the development of the calf is a concept now known as fetal programming (FP).
It's very basic, the nutrients we feed – protein (particularly amino acids), energy (from both carbohydrates and fats), minerals (macro and micro) and vitamins (fat and water soluble), all have very specific, important roles in the development of the embryo and the fetus. If even one of these is in short supply during that period, the development of the embryo and later the fetus can be impeded in some manner that will affect how well it functions and performs later in life. In some cases, particularly for breeding animals, these effects may be noted much later in its life.
It has been well known for many years that many nutrients are critical to this entire process. For most producers the nutrients given the most focus are protein and energy. Adequate provision of both these nutrients is important for production of genetic materials. Remember that both DNA and RNA are essentially proteins. In order for proteins to be synthesized, basic building blocks (dietary proteins and amino acids) must be present to create the structure. Energy is required to facilitate the synthesizing reactions as are enzymes – which are also proteins but involve numerous other components such as minerals and vitamins. The availability of protein has very practical results. For instance, studies have shown that calves born to cows that are fed a diet lacking in protein early in pregnancy, may be more susceptible to respiratory disease later in life. This is believed to be caused by poor lung development during gestation. Further research has examined the incidence of bovine respiratory disease (BRD) in feedlot cattle. Fifteen to 45 percent of cattle have been affected by BRD and one percent to five percent of cattle placed in feedlots die from this disease. Anything done to reduce BRD and respiratory problems will be huge for the industry in the form of additional profits. There is likelihood that FP through proper nutrition can help reduce the incidence of BRD in these cattle. This may also become increasingly important as the industry's access to antibiotics becomes more restricted.
But protein and energy are not the only nutrients we need to focus on. It has been long known that minerals play a role in embryo and fetal development. Wilberg and Neuman reported in 1957 that there was an association between DNA and the trace mineral Manganese (Mn). Based on their work it was suggested that Mn has a functional relationship in the transmission of genetic information. De Carvalho and co-workers (2010) reported that Mn seems intimately involved in the synthesis of protein as well as DNA and RNA. Their results suggested that epiphyseal growth plate cartilage was affected during the early stages of embryo development due to Mn deficiency in the diet of the dam. This went on to result in malformations of the calf's reproductive systems and birth of calves with congenital defects in the skeletal tissues. From this we can infer that if Mn is in short supply in the cow, this deficiency will be present in the reproductive tissues and may be in short supply during the initial phases of cellular division when the transmission of this genetic information is critical.
Additionally, to illustrate the importance of certain nutrients at very early developmental stages, Lequarre and co-workers (2001) reported the presence of Zinc (Zn), Copper (Cu) and Mn dependent enzymes in bovine embryos prior to placental implantation. These enzymes include Superoxide dismutase which is a critical anti-oxidant and is found in virtually every cell in the body. This study showed that this enzyme was present from the very early stages of life. The synthesis and effect of this enzyme requires the presence of Cu, Zn and Mn.
Implications for the Producer
Most cattle producers (beef or dairy) will tell you that they focus strongly on management and nutrition during the period prior to calving and leading up to breeding. But in many cases this focus is driven by a desire to get the cow rebred after calving. For some dairymen, especially in a typical dairy economy, rebreeding and producing a genetically optimal calf often takes a back seat to producing milk. With high producing herds, the competition for nutrients between the cow for milk production and the fetus (early and mid-trimester) is significant. All cattlemen are looking for that subsequent pregnancy but perhaps are not as focused on what is happening with that new conception and the early stages of that embryo. What this concept emphasizes is that not only do we need to be attentive to facilitating the next pregnancy but also that what we are feeding and how we are managing the cow at this point in time has significant and long term implications on the overall life and productivity of the new calf. And in a time when production efficiency is so critical, the producer cannot leave anything on the table.
We know from discussions in previous articles that paying close attention to cow nutrition at breeding and during the pregnancy can go a long way to the production of calves that can perform more effectively, particularly from a reproductive perspective, well into the young animal's life. But what if the producer sells all his calves at weaning? Then we are only looking at keeping that calf for 6-8 months after it is born.
Extensive research has shown that attention to the dam's nutritional program at conceptions and in the weeks and months thereafter can bring improved productivity, efficiency, growth and overall quality to both male and female calves that the producer may plan to sell at or around weaning. Specifically this is illustrated by:
1) Healthier calves at birth with lowered incidences of scouring and/or respiratory disease issues. In general, a stronger, more responsive immune system assuming adequate colostrum is available along with proper care after birth.
2) Better growth rates resulting in heavier calves at weaning
3) A healthier calf throughout the pre-weaning period. This results in lower medicine and vet costs as well as greater gain performance.
4) Potentially better muscle expression resulting in an overall better quality calf.
A study by Du, et al. (2009) reviewed the clear results that fetal programming and maternal nutrition have on the growth performance of offspring. In particular it found that inadequate maternal nutrition during fetal development periods (first 90 days post conception) can reduce the number of skeletal muscle fibers as well as the composition of muscle fibers. It can also reduce growth potential (skeletal and muscle development) and increase fatness of young calves, particularly in areas where fat is not desirable.
Conversely, when proper levels of nutrients are provided, fetal skeletal muscle development can be improved. Additionally fat cell development, known as adipogenesis, may also be enhanced. This does have long term effects such as enhanced marbling potential in these calves. Thus this also results in an overall improvement to the carcass quality of these animals.
Ongoing research has shown that the pregnant cow's diet may also signal how efficiently the fetus should use available nutrients. As indicated, ideally there may be ways by which we can manipulate the cow's diet to influence the developing fetus to build muscle and to deposit intra muscular fat cells (marbling). This improves beef quality particularly in terms of “juiciness” and tenderness. Additionally this could also lead to a reduction in external fat deposition which at this point is largely trimmed and is waste.
Taking Advantage of What We Know
So what is a producer to do if he or she wants to take advantage of all that is known about FP?
Here are some high points:
1) For heifers prior to initial breeding or cows after calving and prior to breeding make sure their nutritional program is as complete as possible for all nutrients. This means, first, a knowledge of what their nutrient requirements are based on size, breed, age, production conditions and weather/environment. It will help to work with a qualified nutritionist to develop these numbers. It will also be necessary to forage test to know what you have to start with.
2) Identify or develop the right supplements that will help meet these requirements as well as maximize cost effectiveness.
3) Particularly, adopt a high quality mineral program. This may need to be somewhat different during these breeding periods than at other times of the production year.
4) Insure that a sound deworming and vaccination program is in place for these animals.
5) Take whatever steps necessary, if possible, to minimize stress.
Adopting a plan to maximize FP opportunities can go a long way to improving the overall performance of the herd and the profitability of the operation. This can benefit all types of producers no matter the end product.
Copyright 2016 – Dr. Stephen B. Blezinger. Dr. Steve Blezinger is a nutritional and management consultant with an office in Sulfur Springs, TX. He can be reached at (903) 885-7992 or by email at firstname.lastname@example.org. For more information please visit us at Facebook/Reveille Livestock Concepts.
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