Appendix 3. Impact of Antibiotic Use on Animal Health and Welfare

Ruth Harrison presented significant criticism of intensive food animal production in her book Animal Machines (1964). In response to the attention the book received, the United Kingdom formed a committee, the Brambell Committee, which produced a report (Brambell 1965) that served as an acknowledgment that animal welfare is a social concern and not limited to concerns of producer groups or individual producers (Hurnik and Lehman 1988; Keeling 2004).

Developed by the Farm Animal Welfare Council in 1993 (Bayvel 2004), the Five Freedoms are perhaps the most widely cited food animal welfare code and practice guidelines. The guidelines state that for an animal’s welfare to remain uncompromised, the animal must have freedom to express normal behavior and freedom from hunger, malnutrition, thirst, discomfort, disease, injury, pain, distress, and fear (FAWC 1993).

The public perceives intensive food animal production as involving widespread use of antimicrobials to treat and prevent disease and promote growth, thus compromising the welfare of the animals (Gade 2002; Pretty 1998). A perception also exists that use of large quantities of antimicrobials is an indication that intensive production systems have inherent problems that need to be addressed (Fox 1984). However, no production system provides an ideal environment for food animals; advantages and disadvantages exist in both intensive and extensive production systems. Indoor systems tend to predispose animals to infectious disease, requiring increased preventive antimicrobial treatment and vaccines, which may mask or counteract problems of animal health and welfare (Rowan and others 1999). Increased incidence of disease and other indications of animal suffering may also occur in alternative animal production systems (for example, free range and organic) (Sandoe and others 2003). Although direct comparisons of disease incidence levels in different housing systems is possible, any apparent relationship between animal welfare and disease prevalence must be interpreted with caution because other factors that vary with stocking conditions may affect disease incidence. Amidst the debates, there is evidence demonstrating that intensification of animal production has improved food animal health, with decreased incidence of infectious disease (Sandoe and others 2003). Intensive systems that are managed well may enable higher levels of welfare than alternative or extensive animal production systems (Gade 2002; Sandoe and others 2003). Intensification facilitates access to animals for disease prevention treatment.

The increasing public support of “disintensification process of livestock production” will require a “science and performance-based approach to appropriate modifications of agricultural practices” (Fox 2002). The Five Freedoms incorporated the scientific approach for assessing animal needs and the value of understanding the provision of good animal husbandry.

Philosophical debates on individual theories concerning the ethics of animal health and welfare are endless (Hurnik and Lehman 1988). Variables such as disease incidence, growth rate, and premature mortality can be measured objectively. However, affective states, such as abnormal behavior, boredom, and pain and suffering, are subjective measures that are more open to substantial disagreement upon observation (Beynen and others 1987). Values intrude into the assessment of animal welfare in fundamental ways (Tannenbaum 1991; Sandoe and Simonsen 1992; Rollin 1993, 1995).

The term “animal welfare” emerged as a concept that allowed society to express ethical concerns regarding inhumane treatment of animals (Duncan and Fraser 1997). Although there are differences in attitudes toward animals, “there is a biological basis for evaluating animal health and welfare, and widespread acceptance that decisions about animal welfare should be based on good scientific evidence” (Kellert 1988). Animal health can be considered as comprising one aspect of the welfare of animals. While the concept is widely regarded as very important, a universally accepted definition of animal welfare does not exist; interpretation of what animal welfare means is dependent upon cultural, political, religious, and scientific perspectives (Bayvel 2004).

One commonly accepted definition is “the welfare of the individual animal is its state as regards its attempts to cope with its environment, with attempts to cope including the functioning of body repair systems, immunological defenses, the physiological stress response, and a variety of behavioral responses” (Broom 1996). More simply, animal welfare is the sum of positive and negative experiences of an animal (Simonsen 1993).

In food animal production, the ethics of caring, which has been an underlying normative force in agriculture, place empathy and nurture as integral points of discussion. Interpersonal human-animal relationships may equate to better care and consideration for farm animals, promoting both better food animal welfare and productivity (Anthony 2003). As such, the humananimal bond explores the values inherent in the nature of animal husbandry, serves as a reference point for animal ethics, and focuses on the moral implications of food animal welfare. Knowledge and caring provided through animal husbandry are recognized as essential prerequisites to maximizing animal welfare (Hemsworth and others 1993).

Increasing public concern for food animal well-being arises due to acceptance of the technologically driven intensification of agriculture while society also considers related conflicting issues such as disappearance of family farms, effects of agriculture on ecosystems, nutritional quality, food safety, and food affordability and distribution (Hurnik and Lehman 1988). What determines fairness for food animals depends on one’s basic moral viewpoint concerning relationships between humans and animals (Sandoe and others 1997). It has become clear that for morally acceptable treatment of food animals, there is no point of objectivity or neutrality from which a baseline can be decided. If a decision is to be made about what is necessary for food animal production to provide the animals with morally acceptable conditions, the decision itself is bound to be relegated to a moral point of view (Sandoe and others 2003). The ethical determination of whether the standards are for morally acceptable food animal welfare is problematic. Conflict arises because public perception does not necessarily equate to optimum standards for food animal health and welfare.

Intensive food animal production systems, however, deprive the animals of natural sunlight and fresh air and prevent the natural behavior of animals, potentially resulting in behavioral problems and stressors that compromise the immune system. Animal welfare research has determined that animals are generally more sensitive and vulnerable to stress and suffering than was previously believed (Broom and Johnson 1993, Webster 1994). Infectious disease remains important, and perhaps creates more problems, as density and herd size increase. While it may be inaccurate to state that increased herd size promotes disease, it could be accurately said that with increasing intensification of food animal populations, opportunities are being missed to decrease and limit the occurrence and dissemination of infectious disease (Garry 2004). Intensive large-scale management systems can improve animal welfare and promote significant improvement in animal production; however, herd or flock productivity is not a suitable gauge for determining animal welfare (Garry 2004).

Management practices that promote high production sometimes benefit animals, but they also increase the risk of production-oriented diseases (Alban 1996). Poor animal health is a major welfare issue, the consequence of which is diminished production and often animal death. Therefore, disease is inextricably linked to economic loss. This reality causes farmers to focus their constant attention on reducing disease in their animals, but the effort they put forth in preventing disease within their animals contains risks and potential economic consequences that are often underestimated (Keeling 2004).

The stakes are high for the food animal industry, pharmaceutical manufacturers, and producers. In particular, the producer faces ongoing pressure to improve efficiency and total production amidst increasing competition. Improving welfare may lead to reduced profits (Fraser 1999, 2001, 2003). As a consequence, while animal welfare may be important to the producer, it is not the motivation for change. Economics and competitiveness are catalysts for change while animal welfare remains a secondary consideration. Overall, most producers view the current paradigm of intensification as the only viable approach to maintaining competitiveness (Garry 2004).

Efficiency and productivity are values; concern for producing economical and plentiful food for consumers is a moral value, as is tempering productivity for the goal of food safety and human health. Thus, it may be possible for food animal production to be expanded to include moral concern for animals. If so, the current primacy of efficiency and productivity in food animal production, as well as the absence of moral concern for animals not linked to human welfare, would need to accommodate a dialectical interchange that would balance the intrinsic value of animal welfare against productivity and low food cost (Rollin 1989).

A new context is evolving for food animal production in which evaluation of beliefs and values toward food animal welfare require attention to the arguments of the public and animal welfare advocates. Consumers in the United States and Europe no longer fully accept the traditional methods of evaluating food animal production systems solely on economic bases (Hurnik and Lehman 1988). However, the ethical dilemmas of public concern, which ignore economic factors, must not be oversimplified. Improvements to food animal welfare can only take place within the context of the forces that drive the free market. The cost to farmers of regulations that impose higher welfare standards could be substantial. Therefore, consumers may have the responsibility to convert an expressed desire for higher welfare standards into an effective demand for welfare-based food animal products even at higher costs (Webster 2001). Producers who modify production practices to improve animal welfare must not be placed at a competitive disadvantage (Hurnik and Lehman 1988).

Antimicrobials are a critical component of the ethics of veterinary medicine, animal husbandry, and food animal production in the United States. These drugs provide benefits related to animal health and welfare, and economic return for the industry. Table 1 illustrates a matrix of the routine use of antimicrobial (and antiparasitic) drugs to sustain intensive animal husbandry and increase productivity in food animals (Mepham 1996). The Ethical Matrix serves as an attempt to create a rational, analytical (that is, scientific) approach to morality through which ethics relating to the production of food animal products could be incorporated into public discourse and political decisions. Like the Five Freedoms, it can be viewed as a checklist to assess the strengths and weaknesses of an animal husbandry system (Webster 2001).

What is considered acceptable animal welfare thus involves not only determining how well off food animals are in a given production system but also evaluating the purpose of production. Plentiful amounts of food at cheap prices and assurance of food safety and animal well-being are inextricably linked to any paradigm for food animal production. From all indications, compromises will have to be made among concerns for the animals, and economic, political, and social factors. Ethics are an integral aspect of discussions of food animal welfare in relation to scientific, socioeconomic, philosophical, or political debate.

The concern of scientists, welfare activists, and legislators would appropriately focus on elements of poor animal welfare that are directly linked to intrinsic features of the production system. The factors include increased disease (for example, post-weaning diarrhea in pigs) through overwhelming exposure to pathogens, environmental exposure, and diminished immunity. The level of infectious disease may serve as a source to evaluate an animal’s welfare, the success of the animal’s coping with its environment, or ultimately, the ethical values provided to the animal by society.

Table 1. Ethical Matrix


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