Written by Dr. Cayla Iske
Have you ever wondered why Oxbow offers different food formulas for young and adult animals? Young and growing animals have significantly different nutrient requirements than mature adults. To put these requirements in context, think about how different an infant or child’s diet looks compared to yours. Because their little bodies are changing rapidly, their diets are composed of different concentrations of nutrients.
Young animals mature & develop each day, gaining muscle and growing bones while their brains and nervous system also develop. These processes require a high concentration of nutrients, specifically protein and calcium, in order to support this major transformation.
Until young animals are weaned, all of their nutritional requirements are met by their mother’s milk or a milk replacement formula. When transitioning to solid foods, it is important to find a diet and feeding regimen that continues to support proper growth and development. We recommend offering a young animal formula for rabbits under 1 year and guinea pigs under 6 months of age to support these needs.
Protein and Amino Acids
Most animals show extremely rapid growth in the first several months of life. For example, rabbits can more than quadruple their weight between 1 and 3 months of age (Masoud et al., 1986). In order to build muscle efficiently, their bodies require many nutrients but especially dietary protein. More specifically, amino acids, the building blocks of protein, are required by an animal.
A well-balanced diet will include a diversity of ingredients that provide protein and a specific amino acid profile. When consumed and digested, protein in the diet is broken down into individual amino acids in the gastrointestinal tract. Certain amino acids are required by animals to form proteins. For example, lysine is important for muscle growth and methionine is needed for development of a healthy coat, making these two amino acids essential in the diet (Carabaño et al., 2009; National Research Council, 1995).
A proper and balanced amino acid profile is extremely important for young and growing animals as imbalances or deficiencies can lead to reduced and improper growth. If the ingredients in the diet alone are not contributing adequate amounts of these amino acids, you may see them added individually in the ingredient list.
Calcium and Energy
Along with muscle comes bone growth and connective tissue formation in every young animal. Between the ages of 2 and 16 weeks, the length of a bunny’s femur bone will grow by 2.5 times (Masoud et al., 1986), requiring calcium in higher amounts (as compared to a fully-grown adult) to accommodate this rapid rate of growth. Additionally, proper formation of tendons and ligaments at this time is critical to ensure proper movement and stability of bone structures. These processes also require calcium and amino acids.
Calcium is also required for a myriad of other essential processes in the body such as muscle, nerve, and immune system function. Given the body will naturally prioritize calcium for these highly essential functions, inadequate levels of calcium in the diet of young animals can lead to reduced growth, weak bones (which increase the risk of injury) or can adversely affect other calcium requiring processes. This need for higher calcium concentrations, as well as the elevated need for protein, is often accomplished by utilizing an alfalfa-based diet, as alfalfa contains naturally higher levels of both calcium and protein.
The growth process also requires a higher level of energy in the diet. Higher dietary protein will help contribute to this need, but slightly increased amounts of fat concentrations (as compared to adult formulas) are also useful to accomplish a higher energy density. Feeding directions can also accomplish greater energy intake by offering a greater volume or feeding an unlimited quantity.
What About Hay?
In addition to an alfalfa-based pelleted diet, loose alfalfa hay provides added vital nutrients in the daily diet of young animals. In addition to alfalfa, it’s important for young animals to have access to a variety of grass hays. Eating a variety of hays adds enrichment into the daily diet of young animals and will make more a much smoother transition to a grass hay-exclusive diet when animals reach adulthood and growth demands begin to slow.
Can Young Animals Have Too Much Protein and Calcium?
If protein and calcium are so important to the growth and development of young animals, does that mean the more, the better? Not necessarily. It is possible to provide too much protein and calcium to young animals, which may result in an animal growing too rapidly. This can not only put strain on bones and joints (which can grow too quickly to fully and properly develop), but also on organs such as the kidneys, which help metabolize protein. It’s important to note that Oxbow’s young animal diets are formulated to provide an appropriate amount of protein and calcium, even when fed free choice.
A young animal has certain unique nutrient requirements to allow for proper growth which occurs rapidly in the first part of life. Generally, a growing animal requires higher concentrations of protein (amino acids), calcium, and energy in the diet to support basic physiological processes in addition to bone, connective tissue, muscle, and coat formation. Oxbow’s young animal diets are specifically formulated to meet these critical nutritional needs.
Carabaño R., Villamide, M.J., García, J., Nicodemus, N., Llórente, A., Chamorro, S.,
Menoyo, D., García-Rebollar, P., García-Ruiz, AJ., De Blas, J.C. 2009. New concepts and objectives for protein-amino acid nutrition in rabbits: a review. Journal of the World Rabbit Science Association 17.1: 1-14.
Masoud, I., Shapiro, F., Kent, R., Moses, A. 1986. A longitudinal study of the growth of the New Zealand white rabbit: cumulative and biweekly incremental growth rates for body length, body weight, femoral length, and tibial length. Journal of Orthopaedic Research 4.2: 221-231.
National Research Council. 1995. Nutrient requirements of laboratory animals. National Academies Press.