Domesticated animals rely on care providers to meet their physiological and behavioral needs. Consequently, management and nutrition are essential to animals' health and well-being. This is especially true in agriculture, in which production methods demand a high level of animal productivity. With continued advances, production systems have tended to become intensified, requiring continual adaptation in management and nutritional practices to ensure that they do not limit animal well-being, health, or production.
Despite improvements in production systems, infectious diseases remain an important health concern, especially in young animals. Proper management and nutrition are central to preventing and controlling most infectious and noninfectious diseases.
Infectious diseases require successful colonization by a specific infectious organism (eg, a bacterium, virus, parasite); however, the mere presence of the microbe is usually insufficient for disease to develop. Environmental and host factors influence whether an animal develops clinical disease or has impaired productivity after infection. Management practices should limit exposure to microbes and mitigate circumstances that predispose animals to the development of clinical and subclinical illness after exposure.
The most effective management method to prevent infectious disease is to eradicate and exclude the organism(s) causing the disease via biosecurity. Eradication and biosecurity are the pillars of managing exotic diseases; typically, however, their implementation is impractical for common endemic diseases.
However, there have been successes in eradication at the national, regional, and farm levels for previously endemic diseases. For example, governments, producer organizations, and individual producers have initiated eradication programs against pathogens such as bovine virus diarrhea viruses and bovine herpesvirus 1. The swine and poultry industries successfully use eradication and biosecurity at the farm level as part of basic herd or flock management to control many diseases.
Because eradication is not feasible for all infectious organisms, the objective of management strategies is to control, rather than eliminate, the disease itself. This often involves identifying and reducing circumstances that favor transmission of the infectious agent, mitigating environmental conditions that contribute to development of disease, and minimizing circumstances that increase host susceptibility. The circumstances that contribute to the development of disease are called risk factors for that disease. Risk factors may be related to the microbe, the animal’s environment, or the animal itself. Identifying and mitigating these risk factors is one goal of the management strategy to prevent a specific disease and to maintain productivity.
Many common diseases have a complex etiology involving interaction of more than one microbe. Others are caused by pathogens for which there are no reliable treatments (eg, viruses, some parasites) or no specific preventive measures (eg, cryptosporidiosis in calves). Prevention and control of these diseases depends on using a management strategy to mitigate risk factors for infection and disease development. These control strategies include general management practices, not necessarily targeting a specific infectious organism, and management practices to address risk factors that are specific for particular pathogens.
Multifaceted approaches using many management practices are the most effective ways to control and prevent common infectious and noninfectious diseases in food animal production. Examples of endemic diseases that require a multifaceted approach include pneumonia in calves and piglets, gastrointestinal disease in neonates, bovine respiratory disease complex in feedlot cattle, infectious causes of infertility, mastitis in dairy cows, and metabolic diseases in dairy cows. Similarly, certain diseases in companion animals, such as respiratory disease in catteries, kennel cough in canine boarding facilities, and infectious and allergic respiratory disease in horses (eg, recurrent airway obstruction), are more effectively controlled by management of risk factors.
The need to implement multifaceted management strategies to maintain health and enhance productivity of animals is likely to increase as automation of animal monitoring, feeding, and milking replaces direct observation of animals. Dairy production systems can use automated monitoring tools to detect estrus, detect lameness, monitor body condition, and evaluate behavior at the feed bunk.
Consumers and interest groups often pressure those involved in animal agriculture to address concerns about some current industry practices. Examples of these concerns are potential links between drug use in animals and antimicrobial resistance in human pathogens, animal waste management and environmental contamination in intensive production systems, the role of management practices in foodborne illnesses and maintenance of zoonotic pathogens, and the impact of certain management practices on animal welfare.
Even if there is not conclusive evidence linking animal production to public health issues, management practices will almost certainly be reevaluated in response to the perception of such links and changed as appropriate. Changes to management practices will take different approaches; however, they must still focus on maintaining animal health and production. Often, identifying and making changes requires investment in research to ensure any management changes are practical and likely to achieve the desired outcome.
Nutritional management is part of overall animal management and is essential to health and productivity. Nutrition plays a role in influencing the animal's susceptibility to disease (eg, feline lower urinary tract disease) as well as in managing certain diseases (eg, diabetes in companion animals, hyperlipidemia, clinical and subclinical ketosis in dairy cattle). Rations/diets must meet basic physiologic needs (eg, energy, protein, fats, carbohydrates, vitamins, minerals) of the animal and ensure optimal growth and productivity. Nutritional management should consider digestive function, age, sex, breed, lactation status, and gestational status, as well as physical activity and environmental conditions.
Nutritionally related diseases include diseases of nutritional excess (eg, direct toxic effect, digestive upset), nutritional deficiency (either a primary or secondary deficiency), and nutritional imbalance. In animal agriculture, health and production are heavily influenced by feeding management. Feed preparation and delivery are often as important to animal health and productivity as the actual nutritional value of the ration itself. Inadequacies in nutritional delivery can cause disease (eg, ruminal acidosis, laminitis) or increase susceptibility to disease (eg, Clostridium perfringens type D enterotoxemia). In many production animal sectors, automated management tools have made it easier to ensure consistent nutrition and feed availability; however, the ability to monitor the performance of automated systems will require new tools.
Nutritionally related diseases in companion animals include both diseases of excess (eg, developmental orthopedic disease in dogs related to excess calcium and energy) and diseases of deficiency (eg, blindness in cats related to taurine deficiency). Feeds and feeding management can also influence animal health if feeding results in exposure to foodborne hazards, such as physical objects (eg, sharp items), chemicals (eg, mycotoxins, toxic plants), allergens (eg, dust mites, mold spores), or microbes (eg, molds, Salmonella spp). Nutritional and waste management practices are also important in preventing and controlling infectious diseases that are transmitted by fecal-oral transmission (eg, salmonellosis, paratuberculosis in ruminants, and toxoplasmosis in cats).
