Generated Summary
This study presents an economic analysis of the impact of growth-promoting antibiotics (GPAs) on poultry production. Utilizing data from a non-randomized controlled trial conducted by Perdue Farms, Inc., the research examines the economic effects of removing GPAs in commercial broiler chickens. The methodology involves assessing the cost of feed with GPA additives, the feed conversion ratio (FCR), and changes in the value of broiler chickens at harvest due to differences in weight gain, mortality, and condemnation rates. The study aims to contribute to the ongoing debate concerning the continued use of antibiotics for growth promotion in food animals, providing insights into the economic implications for producers and the poultry industry.
Key Findings & Statistics
- The use of antibiotics to enhance growth and feed efficiency and reduce mortality in broiler production was introduced without rigorous testing as to efficacy some 50 years ago.
- Improvement in growth due to antibiotics was first described in the mid 1940s, and within five years the addition of GPAs became common practice.
- During this initial period, it was hypothesized that the antibiotic growth effect was due to the reduction of pathogenic bacteria in the intestinal tract of chicks.
- The average market weight of broilers has increased nearly 50%, and the time needed for broilers to reach market weight and the amount of feed required to produce one pound of broiler meat have both declined approximately 35% from 1955 to 1995.
- Estimates of the amounts of GPAs used in U.S. animal production range from 3.1 million pounds to approximately 25 million pounds annually.
- Early studies, conducted from 1950 to 1960, showed mean increases in body weight of 8.5%-8.8% using penicillin and 10.2%-12.3% using tetracyclines.
- From 1968 to 1980, median body weight increases were found to be 11% for penicillin, 8%-10% for the tetracyclines, and 4%-7% for the “new” antibiotics.
- Using the Delmarva Peninsula data set, the study found that withdrawing GPAs increased the market value of the chickens by an amount on the order of $0.0016 per chicken, but increased the growing cost by a larger amount of $0.0069.
- For the Delmarva Peninsula, withdrawing GPAs from the feed increases the net value of the flock by $0.0009 to $0.0097 per chicken.
- Using the North Carolina data set, withdrawing GPAs increased the net value of the flock by $0.0048 to $0.0135 per chicken.
- The net effect of GPA use is a lost value of $0.0093 per chicken (about 0.45% of total cost).
Other Important Findings
- Considerable controversy persists regarding the use of human antibiotics to promote growth in animals raised for food.
- The study found that the use of GPAs in poultry production is associated with economic losses to the producers.
- The use of antibiotics for growth promotion in food animal production is related to the contribution of this use to increasing rates of antibiotic resistance.
- Studies have shown that the use of GPAs contributes to contamination of flocks and food products by antibiotic resistant pathogens, including Campylobacter, Salmonella, Enterococcus and Escherichia coli.
- In 2004 the U.S. Food and Drug Administration banned enrofloxacin (a fluoroquinolone applied for therapeutic uses, not growth promotion) in food animals on the grounds that its use contributed to fluoroquinolone resistance in human pathogens.
- The European Union, in 1999, banned the use of most antibiotics for growth promotion to preserve the effectiveness of important human drugs.
- The change in total revenue received by the grower is used to estimate the change in the market value of the unprocessed chickens.
- The study also found that the use of GPAs increases the market value of the chickens by an amount on the order of $0.0016 per chicken, but increases the growing cost by a larger amount of $0.0069.
- The study is only of the costs of removing GPAs from poultry production and does not consider the potential benefits of GPA removal in terms of medical and public health burdens related to the impacts of increasing risks of antibiotic-resistant infections.
Limitations Noted in the Document
- The study utilized secondary data, and inter-trial differences were not available, preventing the calculation of confidence intervals.
- The assignment of farms was not randomized, and there may have been some undetected factors that could have affected the results.
- No calculation of veterinary costs was included.
- No cost was attached to the variability in the weight of broiler chickens.
- The results are normalized on the initial flock size (number of chicks). Normalizing on finished flock size (Qa), or on total weight of the finished flock, produces similar results.
- The study is limited by the lack of data on the economic value of GPA use and some researchers have argued that more economic analyses of productivity gains associated with GPAs are needed.
Conclusion
This economic analysis provides critical insights into the financial implications of using GPAs in poultry production. The findings indicate that the benefits of GPA use, such as gains in feed conversion ratios, were insufficient to offset the costs associated with the biological agents, leading to a net economic loss for producers. The study emphasizes that the use of GPAs is associated with economic losses to the producers and that these data are of considerable importance in the ongoing national debate concerning the continued use of antibiotics for growth promotion of food animals. The results highlight a concerning trend: the costs associated with GPA use outweigh the benefits, suggesting a need for reconsideration of current practices. Based on the industry study and the resulting economic impact, the use of GPAs in U.S. poultry production should be reconsidered. The removal of GPAs from the feed increases the net value of the flock. The ultimate value of a given flock of chicks is changed due to differences in weight gain, mortality, and condemnation rates. Although there have been some recent statements regarding current practices in the use of non-therapeutic antibiotics, the findings in this analysis have important implications for public health policy. GPA-associated gains in feed conversion ratios were insufficient to offset the cost of the biological agents. Based on the industry study and the resulting economic impact, the use of GPAs in U.S. poultry production should be reconsidered. The economic analysis is based on the only large data set currently available in the U.S., conducted under conditions of current commercial broiler poultry production.