Cited by 154Genetically Modified Organisms ResearchAgricultural safety and regulationsAnimal Genetics and Reproduction

The DOI matches its Crossref record; 107 of the 119 references it cites were found in a registry or an index; none of the 137 sources its claims cite is checked for support yet.

Prevalence and impacts of genetically engineered feedstuffs on livestock populations1

Van Eenennaam, A. L., Young, A. E.·2014·Journal of Animal Science

Abstract

Globally, food-producing animals consume 70 to 90% of genetically engineered (GE) crop biomass. This review briefly summarizes the scientific literature on performance and health of animals consuming feed containing GE ingredients and composition of products derived from them. It also discusses the field experience of feeding GE feed sources to commercial livestock populations and summarizes the suppliers of GE and non-GE animal feed in global trade. Numerous experimental studies have consistently revealed that the performance and health of GE-fed animals are comparable with those fed isogenic non-GE crop lines. United States animal agriculture produces over 9 billion food-producing animals annually, and more than 95% of these animals consume feed containing GE ingredients. Data on livestock productivity and health were collated from publicly available sources from 1983, before the introduction of GE crops in 1996, and subsequently through 2011, a period with high levels of predominately GE animal feed. These field data sets, representing over 100 billion animals following the introduction of GE crops, did not reveal unfavorable or perturbed trends in livestock health and productivity. No study has revealed any differences in the nutritional profile of animal products derived from GE-fed animals. Because DNA and protein are normal components of the diet that are digested, there are no detectable or reliably quantifiable traces of GE components in milk, meat, and eggs following consumption of GE feed. Globally, countries that are cultivating GE corn and soy are the major livestock feed exporters. Asynchronous regulatory approvals (i.e., cultivation approvals of GE varieties in exporting countries occurring before food and feed approvals in importing countries) have resulted in trade disruptions. This is likely to be increasingly problematic in the future as there are a large number of "second generation" GE crops with altered output traits for improved livestock feed in the developmental and regulatory pipelines. Additionally, advanced techniques to affect targeted genome modifications are emerging, and it is not clear whether these will be encompassed by the current GE process-based trigger for regulatory oversight. There is a pressing need for international harmonization of both regulatory frameworks for GE crops and governance of advanced breeding techniques to prevent widespread disruptions in international trade of livestock feedstuffs in the future.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This review concludes that GE feedstuffs are compositionally equivalent to conventional feed and that livestock performance, health, and animal-product composition are comparable between GE-fed and non-GE-fed animals, based on feeding studies and field data from over 100 billion U.S. animals (2000–2011). It also warns that asynchronous regulatory approvals and zero-tolerance policies are causing trade disruptions and will become more problematic with second-generation GE crops and gene editing.

Key findings

  • Experimental feeding studies consistently show performance and health of GE-fed animals comparable to those fed near-isogenic non-GE lines; no study has revealed differences in the nutritional profile of milk, meat, or eggs, and neither recombinant DNA nor intact recombinant protein has been detected in animal products.
  • U.S. field data from 1983–2011, including over 100 billion animals after GE crop introduction, showed no unfavorable or perturbed trends in livestock health and productivity; available health indicators improved over time (e.g., dairy somatic cell count fell from 304,000 cells/mL in 1995 to 217,000 in 2011; broiler feed-to-gain fell from 2 in 1985 to 1.91 in 2011; cattle and poultry condemnation/mortality rates decreased).
  • GE feed dominates global trade: an estimated 92.75–95.9% of traded soybeans, 64–92.7% of traded corn, 69% of cotton, and 84.2–85% of canola may contain GE material; non-GE-fed animal products are a niche market (<5% of U.S. animals), with organic livestock shares such as 0.33% of broilers, 1.97% of layers, 0.20% of turkeys, 0.34% of beef cows, 2.78% of dairy cows, and 0.01% of hogs in 2011.
  • Asynchronous approvals caused trade disruptions, including China’s rejection of U.S. corn: 3.3 million t were subject to rejection and diverted shipments (1.4 million t) or canceled/deferred sales, with estimated losses up to $2.9 billion; GE crops added an estimated 122 and 230 million t to global soybean and corn production, reduced pesticide spraying by 499 million kg (−8.7%), and lowered environmental impact by 18.1%.

Methods

  • Design: narrative review of peer-reviewed livestock GE feeding studies and animal-product composition studies, plus analysis of publicly available U.S. livestock productivity and health data from 1983 through 2011, comparing pre-GE (1983–1994) and high-GE-feed (2000–2011) periods.
  • Data: broiler, dairy, hog, and beef industries; sources included USDA Economics, Statistics, and Market Information System, USDA National Agricultural Statistics Service, USDA FSIS, National Chicken Council, and published audits; global production/trade data came from USDA Foreign Agricultural Service, FAO, Brookes and Barfoot, and others.
  • Analysis: regression analyses were performed for 1983–1994 and 2000–2011, and slopes between periods were compared using an unpaired t test where data were available; feeding-study and trade data were summarized descriptively.

Limitations

  • Paper-stated: whole-food animal feeding trials have low power to detect adverse effects, are limited by how much GE feed can be included without nutritional imbalance, and contribute little to safety assessment once compositional equivalence is established; fewer than 100 long-term (>90 d) and multigenerational target-animal GE feeding studies exist in the peer-reviewed literature.
  • Paper-stated: long-term and multigenerational studies should be reserved for cases where reasonable doubt remains after a 90-d feeding trial triggered by a potential hazard, and statistically significant differences in such studies are not necessarily adverse effects.
  • Evident from the text: the field analysis is observational, relies on aggregated publicly available data and regression slope comparisons, and cannot establish causality or individual-level exposure; the review is described as brief/narrative rather than a systematic review or meta-analysis.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.2527/jas.2014-8124

Cites

107 of 107 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

0 of 137 cited sources checked · 0 supported · 0 flagged

Show all 74 claims

  • Probably not a substantial claim. 92
  • It may state two separate claims as one. 76
  • The quote only partly states this claim. 1
134 of 134
  • The paper relies on this without support.

    DNA and protein are normal components of the diet and are digested.

    “Because DNA and protein are normal components of the diet that are digested”
  • The paper relies on this without support.

    Globally, countries that are cultivating GE corn and soy are the major livestock feed exporters.

    “Globally, countries that are cultivating GE corn and soy are the major livestock feed exporters.”
  • The paper relies on this without support.

    Asynchronous regulatory approvals have resulted in trade disruptions.

    “Asynchronous regulatory approvals (i.e., cultivation approvals of GE varieties in exporting countries occurring before food and feed approvals in importing countries) have resulted in trade disruptions.”
  • The paper relies on this without support.

    Plant varieties developed through other processes of achieving genetic changes, such as radiation mutagenesis, go through no formal risk assessment before being placed on the market.

    “By contrast, plant varieties developed through other processes of achieving genetic changes (e.g., radiation mutagenesis) go through no formal risk assessment before being placed on the market.”
  • The paper relies on this without support.

    The United States and Australia/New Zealand explicitly do not require a 90-day subchronic rodent feeding study or actively discourage their conduct due to their negligible scientific value.

    “The United States and Australia/New Zealand explicitly do not require a 90-d subchronic rodent feeding study or actively discourage their conduct due to their negligible scientific value.”
  • The paper relies on this without support.

    GE proteins are digested in the gut and no intact GE protein has been found in the bloodstream.

    “especially given that GE proteins are digested in the gut and no intact GE protein has been found in the bloodstream.”
  • The paper relies on this without support.

    There are a large number of second-generation GE crops with altered output traits for improved livestock feed in the developmental and regulatory pipelines.

    “there are a large number of 'second generation' GE crops with altered output traits for improved livestock feed in the developmental and regulatory pipelines.”
  • The paper relies on this without support.

    In a typical U.S. broiler operation, chickens are fed for 42–49 d on diets composed of approximately 35% soybean meal and 65% corn grain.

    “in a typical U.S. broiler operation, chickens are fed for 42-49 d on diets that are composed of approximately 35% soybean meal and 65% corn grain”
  • The paper relies on this without support.

    The average U.S. dairy cow has a productive life of 5 yr with 3 conceptions, 3 gestations, and 3 lactations.

    “The average U.S. dairy cow has a productive life of 5 yr with 3 conceptions, 3 gestations, and 3 lactations.”
  • The paper relies on this without support.

    A typical U.S. dairy diet contains 50% corn silage, 20% corn grain, and 10% dehulled soybean meal.

    “A typical U.S. dairy diet contains 50% corn silage, 20% corn grain, and 10% dehulled soybean meal.”
  • The paper relies on this without support.

    Many cows receive large portions of their rations as ground corn grain, fuzzy cottonseed, or roasted full-fat soybeans.

    “Also, many cows receive large portions of their rations as ground corn grain, fuzzy cottonseed (no processing except for removal of the lint), or roasted full-fat soybeans.”
  • The paper relies on this without support.

    Other GE sources of animal feed include alfalfa hay, sugar beet pulp, corn distillers grains or other coproducts from corn processing, cottonseed meal, canola meal, and soy hulls.

    “Other GE sources of animal feed include alfalfa hay, sugar beet pulp, corn distillers grains or other coproducts from corn processing, cottonseed meal, canola meal, and soy hulls.”
  • The paper relies on this without support.

    A beef cow on the range might consume only some GE alfalfa hay, but her progeny entering the feedlot might be expected to consume a ration containing high quantities of GE feed during their 120 d in the feedlot before harvest.

    “A beef cow on the range might consume only some GE alfalfa hay, but her progeny entering the feedlot might be expected to consume a ration containing high quantities of GE feed during their 120 d in the feedlot before harvest.”
  • The authors state this as an assumption.

    If animal feed derived from GE crops had deleterious effects on animals consuming GE feed, then animal performance and health attributes in these large commercial livestock populations would have been negatively impacted.

    “It would be reasonable to hypothesize that if animal feed derived from GE crops had deleterious effects on animals consuming GE feed, then animal performance and health attributes in these large commercial livestock populations would have been negatively impacted.”
  • The paper relies on this without support.

    All animals arriving at USDA-inspected slaughter facilities undergo both antemortem and postmortem inspections to identify abnormalities.

    “All animals arriving at USDA-inspected slaughter facilities undergo both antemortem and postmortem inspections to identify abnormalities.”
  • The paper relies on this without support.

    Carcasses are condemned postmortem if there are visible lesions or tumors present on organs and carcasses.

    “Carcasses are condemned postmortem if there are visible lesions or tumors present on organs and carcasses.”
  • The paper relies on this without support.

    Animals and humans regularly ingest DNA and RNA as part of traditional diets without consequence.

    “It is important to note that animals and humans regularly ingest DNA and RNA as part of traditional diets without consequence.”
  • The paper relies on this without support.

    Approximately 9 billion broilers are processed annually in the United States.

    “approximately 9 billion broilers are processed annually in the United States”
  • The paper relies on this without support.

    Only Brazil currently requires mandatory labeling of products from animals that consume GE feed.

    “only Brazil currently re -quires mandatory labeling of products from animals that consume GE feed.”
  • The paper relies on this without support.

    In some countries, mandatory food labeling regulations target the presence of GE components in the finished product (e.g., Australia, New Zealand, and Japan), whereas in other countries, regulations target foods that use GE technology as a part of the production process (e.g., the EU, Brazil, and China).

    “In some countries, mandatory food labeling regulations target the presence of GE components in the finished product (e.g., Australia, New Zealand, and Japan), whereas in other countries, regulations target foods that use GE technology as a part of the production process (e.g., the EU, Brazil, and China).”
  • The authors state this as an assumption.

    The volume of traded soybeans required to be identity-preserved certified non-GE is segregated from supplies that may contain GE soybeans.

    “if it is as -sumed that this volume of traded soybeans is segregated from supplies that may contain GE soybeans”
  • The paper relies on this without support.

    Harvesting machinery and storage facilities are shared among different agricultural production systems.

    “realities of agricultural production systems where harvesting machinery and storage facilities are shared among different production systems”
22 of 22

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • GE feed crops are said to have been introduced in two different years

    Minor

    The paper repeatedly gives 1996 as the introduction year, but the description of Table 4 says 1986.

  • Table 7 cottonseed-meal percentage does not match its trade figures

    Minor

    Table 7 lists 0.63 million t as the share of cottonseed-meal trade that may contain GE material and 0.6 million t as total trade. The listed share is 105% of total trade, not the reported 45%.

    Reported 45 · recomputed 105

2 of 2

Citations

Cites

1 retracted

Flagged first, then by citations

Show all 119 references

12 of the 119 references couldn’t be matched to a known paper.

Research works printed but not linked: 5

  1. European Feed Manufacturers' Federation, 2013, XXVI FEFAC congress 2013, The feed chain in action.
  2. European Food Safety Authority, 2011, Opinion of the scientific committee/scientific panel. Statistical significance and biological relevance, EFSA J., 9, 2372
  3. International Life Sciences Institute, 2007, Best practices for the conduct of animal studies to evaluate crops genetically modified for output traits
  4. James, 2013, Global status of commercialized biotech/GM crops: 2013
  5. Velmirov, 2008, Biological effects of transgenic maize NK603xMON810 fed in long term reproduction studies in mice, Bundesministerium fur Gesundheit, Familie und Jugend.

Cited by

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Items 101–145 of 145

Metadata

Authors
Van Eenennaam, A. L., & Young, A. E.
Affiliations
  • Department of Animal Science, University of California, Davis 95616
  • University of California, Davis (US)
Venue
Journal of Animal Science
Published
2014-10-01
Volume
92
Issue
10
Pages
4255-4278
ISSN
  • 0021-8812 (ISSN-L)
  • 1525-3163
OpenAlex
W2087980057
Cited by
154
References
119
Citations by year
2026: 6 · 2025: 7 · 2024: 6 · 2023: 10 · 2022: 16 · 2021: 3 · 2020: 18 · 2019: 11 · 2018: 10 · 2017: 31 · 2016: 17 · 2015: 18
FWCI
2.49
Type
journal article
Language
en
Open access
closed
Locations
  • Journal of Animal Science (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Life Sciences › Agricultural and Biological Sciences › Plant Science › Genetically Modified Organisms Research
  • Life Sciences › Agricultural and Biological Sciences › Food Science › Agricultural safety and regulations
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Animal Genetics and Reproduction
Keywords
livestock performance, livestock health, genome editing, international regulatory harmonization, animal feed
MeSH terms
Animals, Animal Feed, Breeding, Edible Grain, Eggs, Female, Genetic Engineering, Meat, Milk, Pregnancy, Prevalence, DNA, Plant, Pregnancy Rate, Livestock

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