Animal nutrition

Animal nutrition is the branch of veterinary science that studies how food influences animal health and performance. Like humans, animals need a balanced diet to grow, reproduce, and stay strong (1, 2). Think of nutrition as the fuel for an engine: without adequate gasoline, the car won't move forward, and without essential nutrients, the animal will lose health. Ensuring that each species and individual receives what they need—based on their age, activity level, and physiology—allows them to reach their full genetic potential (1, 2).

Fundamentals of Animal Nutrition

Every animal requires six basic nutrients in its diet: water, carbohydrates, proteins, lipids (fats), minerals, and vitamins (3). Each one performs specific functions: for example, water hydrates and regulates temperature; carbohydrates and fats provide energy for movement and warmth; proteins are like the "bricks" that build muscles and tissues; and vitamins and minerals act as tiny keys that activate body reactions. Furthermore, each species and life stage has its own unique needs. For example, puppies and growing animals need more protein to develop their organs, while older animals may require calcium supplements to keep their bones strong.

Digestive systems also vary greatly. Ruminants, such as cows and sheep, have their stomachs divided into four compartments (rumen, reticulum, omasum, and abomasum). These microenvironments house millions of bacteria that ferment grass fiber and produce volatile fatty acids, which are their primary source of energy (4). In contrast, animals such as pigs, poultry, dogs, and cats have a single stomach (like us), so they require more concentrated, nutrient-rich, and easily digestible foods. Dogs, for example, need Omega-3 and Omega-6 essential fatty acids in their diet, as their bodies do not manufacture them (5). In general, a balanced diet covers these needs without deficiencies, as each nutrient works in concert with the others to keep the animal healthy.

• Water: Vital to all diets, it is the medium where metabolic reactions occur.

• Proteins: Provide amino acids for growth and repair of tissues (muscles, hair, skin).

• Carbohydrates: Transformed into quick energy; they come from grains and forage.

• Fats: Concentrated sources of energy and essential for absorbing some vitamins.

• Vitamins and minerals: Although used in small quantities, they regulate metabolism (e.g., calcium for bones, vitamins for vision, or coagulation).

• Fiber (in herbivores): Stimulates digestion; cows ferment it in the rumen to generate extra energy (4).

Importance of a Good Diet

Proper nutrition is key to animal health and well-being. It allows animals to develop properly, defend themselves against disease, and be more productive. For example, a well-fed cow produces more quality milk, a chicken eats more grains with less waste, and an active dog maintains a shiny coat and greater energy. In agriculture and livestock, nutrition directly impacts milk, meat, and egg production (1, 2). A malnourished animal grows slowly, gets sick more easily, and its performance plummets (it has less lactation or lays fewer eggs). Studies confirm that "a balanced diet is key to animal growth, reproduction, and disease resistance" (2). Thus, investing in good nutrition is an investment in long-term health and productivity.

Furthermore, optimal nutrition benefits the sustainability of the system: healthy animals require fewer medications (reduction in antibiotics), live longer, and utilize the feed better. This improves the quality of the final products (leaner meat, more nutritious milk) and reduces the environmental impact per animal. In short, caring for animals' diets not only promotes their happiness and longevity, but also ensures better quality food for people (2, 6).

Types of Animal Feed

Animal feed is classified into forages and feeds (concentrates) (7). Forage includes fresh grass, hay, straw, and silage (fermented fodder). It is the basis of the diet of herbivores such as cows, horses, and sheep. Feed, or concentrate, on the other hand, consists of mixtures of grains (corn, wheat, barley), by-products (soybean meal, cottonseed meal, fish meal), and additives. These concentrated rations are widely used in high-producing pigs, poultry, and cows to ensure they receive sufficient protein, energy, and minerals. In general, food grains—especially corn and soybeans—are the world's most important sources of animal feed (8).

A practical example: a dairy cow eats primarily fresh grass, hay, or corn silage. These plant fibers are fermented by its rumen microbes to generate energy (4). In addition, it is given ground corn and soybean meal as energy and protein concentrates (9). Thanks to this balanced diet, the cow produces many liters of nutrient-rich milk. Another example: poultry is often fed corn, soybeans, and minor additives to grow quickly and strongly, as their stomachs cannot ferment cellulose like a cow's.

In contrast, an adult dog—which cannot consume forage—needs prepared food with balanced ingredients. For example, the majority of its diet should be rich in protein (from meat or fish) and contain carbohydrates and healthy fats. Its commercial food usually includes Omega-3 and Omega-6 essential fatty acids, as dogs cannot synthesize them (5). These nutrients improve skin, coat, and joint health. Extra vitamins and minerals (such as calcium and B vitamins) are often added to cover any deficiencies. Thus, a well-formulated kibble dish covers all daily needs without additional supplements.

Technological Advances in Animal Nutrition

Animal nutrition is undergoing a technological revolution. On the one hand, artificial intelligence and sensors are being used to optimize diets. Big data and AI are used to analyze the weight, feed intake, and health of each animal on the farm. From this data, personalized diets are created: for example, a cow's or pig's ration is adjusted to maximize growth without wasting resources (10).

On the other hand, new protein sources and additives are being researched. Among alternative proteins, insects (crickets, worms) and algae (spirulina, chlorella) are gaining ground as feed ingredients (11). Meat is also being grown in laboratories to be added to feed without raising whole animals. These options reduce the use of land and water in food production (6, 11). Furthermore, bioengineering is working on genetically modified animals and ingredients: for example, pigs are already being developed to produce meat with more Omega-3 (12). There are even experiments using 3D printers to manufacture feed with special shapes and textures that improve palatability (13). Together, these innovations seek to make nutrition more efficient, sustainable, and tailored to each species.

Ethical Considerations

Animal nutrition also has ethical and environmental implications. Intensive livestock farming fed with concentrated feed can generate serious problems: high greenhouse gas emissions, deforestation for grain cultivation, and excessive water use (14). Furthermore, intensive practices often involve the continuous confinement of animals, which affects their welfare. Furthermore, the indiscriminate use of antibiotics to stimulate growth or prevent disease in mass diets contributes to bacterial resistance, a risk to human health (14).

Therefore, responsible feeding is emphasized today: prioritizing local forages, rotational grazing systems, natural feeds (fewer additives), and supplementing only what is necessary. Some pet owners are also increasingly concerned about vegetarian or raw diets for their dogs and cats, although these require caution when planning homemade meals. In any case, the ethical goal is to feed animals so they live healthy and happy lives without compromising the planet's resources or their well-being (6, 14).

Conclusion

In summary, good animal nutrition is the foundation for health, productivity, and sustainability in livestock and pet care. It ranges from basic principles (essential nutrients and digestion) to advanced technologies (AI, alternative proteins) (2, 10). Understanding what each species eats—whether a dairy cow ruminating on grass or a domestic dog on balanced kibble—allows for more efficient diets. At the same time, addressing ethical and environmental considerations ensures more responsible animal-based food production. Ultimately, feeding animals well not only improves their lives and their products (milk, meat, eggs), but also protects our own future (2, 6).

Sources: Information based on specialized studies and articles on animal nutrition.

(1, 2) Nutrición Animal: Qué Estudia y Su Importancia https://elblogdelasaves.com/que-estudia-la-nutricion-animal/

(3) Conceptos Básicos de Nutrición en perros y gatos https://ri.conicet.gov.ar/handle/11336/53482

(4) El aparato digestivo de los rumiantes https://es.extension.umn.edu/nutrici%C3%B3n-l%C3%A1ctea/sistema-digestivo-de-rumiantes

(5) Omega 3 para perros: Beneficios y usos esenciales para la salud canina - ALIMASCOTA.ES https://alimascota.es/omega-3-para-perros-beneficios-y-usos-esenciales-para-la-salud-canina

(6 ,11 ,14)Proteínas alternativas: El futuro de la alimentación sostenible https://www.ambientum.com/ambientum/cambio-climatico/la-revolucion-de-la-alimentacion-sostenible-el-futuro-de-las- proteinas-alternativas.asp

(7, 8)Alimento para animales - Wikipedia, la enciclopedia libre https://es.wikipedia.org/wiki/Alimento_para_animales

(9)Alimentación del ganado lechero | Agrovet Blog https://blog.agrovetmarket.com/alimentacion-nutricion-ganado-lechero/

(10, 12, 13) FIGAP | EXPO CIENTÍFICA Y TECNOLÓGICA DE LA INDUSTRIA PECUARIA, Foro Internacional Agropecuario más importante de América Latina | Novedades tecnológicas en nutrición animal para el sector agroindustrial https://figap.com/blog/paginas/novedades-tecnologicas-en-nutricion-animal-para-el-sector-agroindustrial