Diet | Puppy food: how nucleotides help strengthen the immune system

Even though dogs start to develop their immune system while they are still foetuses in the womb, maternal immunoglobulins have a very limited capacity to penetrate the placental barrier. In fact, most immunoglobulins are obtained from the mother’s milk.

When should solid food be introduced?

Healthy eating habits will contribute to better puppy development. Before going into details about puppy food and the relationship between the immune system and nucleotides, this video will give you a few tips about how to train your puppy to develop some healthy eating habits right from the outset:

High mortality in puppies with an immature immune system

An estimated 30% of puppies die in the first few weeks of life (Dumon 2005). Young animals are more susceptible to viral, bacterial and parasitic infections, so boosting newborn puppies’ immune systems is really important.

Even though dogs start to develop their immune system while they are still foetuses in the womb, maternal immunoglobulins have a very limited capacity to penetrate the placental barrier. In fact, most immunoglobulins are obtained from the mother’s milk.

Immunity through mother’s milk: colostrum

Mother’s milk is the main source of immunity for puppies, particularly the colostrum. In fact, most immunoglobulins are acquired during the first 24 hours, as this is when colostrum contains the most antibodies and the puppy’s intestinal wall can still absorb them. From then on, the concentration of antibodies in the colostrum gradually decreases. Rather curiously, not all puppies born in a single litter acquire the same immunity, as those born later receive fewer maternal antibodies as their concentration in the colostrum decreases.

Colostrum will confer puppies with protection for 1–2 months. After this period, young dogs have to activate their own immune system to protect themselves from external antigens.

Boosting the immune system through nutrition

The right nutrition during gestation, lactation and growth helps boost the immune system and increases protection against infections. In addition, puppies are most susceptible precisely at the time they are introduced to a solid diet, so this the ideal moment to protect them.

When should solid food be introduced?

Puppies can be given dry food when they are 2.5–4 weeks old. The introduction of puppy food should not be delayed beyond this period, as the mother’s milk can no longer provide all the nutrients required by the dog. A diet with sufficient nutrients reduces the risk of growth disorders and helps maintain a good level of overall health.

Which puppy food ingredients help stimulate immunity?

The ingredients that help strengthen the puppy’s immature immune system are called “immunonutrients”. Some of the most important ones are:

• Nucleotides

Nucelotides are necessary for cell replication and protein synthesis and, since the de novo synthesis of nucleotides expends a great deal of energy, if they are supplied in the animal’s diets, it will support and encourage the puppy’s growth and development.

• Plasma immunoglobulins

Administered in the form of natural IgG concentrates, plasma immunoglobulins boost the immune system by directly binding to intestinal pathogens, preventing them from adhering to the mucosa and producing toxins.

• Prebiotics

Prebiotics are a form of natural fibre that promote the growth of a healthy gut microbiota (lactobacilli and bifidobacteria).

Now we shall go into more detail about the action of the nucleotides and their protective role when supplied in the puppy’s diet.

Natural nucleotides in mother’s milk

We have known about the high concentrations of nucleotides found in human breast milk and their role in a baby’s immune development for years now. The European Union therefore recommends that infant formulas should be supplemented with nucleotides.

A female dog’s milk contains a much higher concentration of nucleotides than human milk, which means puppies are highly dependant on receiving nucleotides in their diet.

The nucleotides in puppy food stimulate antibody production

Research has shown that supplementing the diet with nucleotides boosts puppies’ defences in terms of both humoural and cellular immunity (Romano et al., 2006). 

Nucleotides act at a molecular level, specifically they influence cell replication. They are also constituents of both DNA and RNA, in other words, the nitrogenous bases adenine, guanine, cytosine, thymine and uracil (A, G, C, T and U), which in combination with other molecules form the chains of nucleic acids.

In short, they play a role in cell replication by participating  in the transcription process (DNA --> RNA) necessary for protein synthesis. Some of the cells directly involved in protecting the body have a very limited ability to synthesis proteins from amino acids, so it is essential that nucleotides are supplied through the puppy’s diet in order for the immune system to function correctly. Namely, we are referring to cells that are as important as haematopoietic cells, leukocytes and intestinal mucosal cells, for example.

In conclusion, the choice of a puppy food (or feed) should take into account the immaturity of the animal’s immune system and, whenever possible, diets with immunonutrients such as nucleotides, immunoglobulins and prebiotics are recommended.

Bibliography:

• Romano V, Martinez-Puig D, Torre C, Iraculis N, Vilaseca Ll, Chetrit C. Dietary Nucleotides Improve the Immune Status of Puppies at Weaning. 2006 AAVN meeting. Louisville (KY, USA)

• Dumon C. Pathologie néonatale du chiot. EMC - Vétérinaire. March 2005;2 (1):30-53

• Jeusette I, Romano V, Salas A, et al. Research Report: IMMUNONUTRITION IN PUPPIES. Affinity Petcare, 08174 St. Cugat del Vallès, Barcelona (SPAIN)