The Chimpanzee Genome Project was an effort to determine the DNA sequence of the chimpanzeegenome. Sequencing began in 2005 and by 2013 twenty-four individual chimpanzees had been sequenced. This project was folded into the Great Ape Genome Project.
In 2013 high resolution sequences were published from each of the four recognized chimpanzee subspecies: Central chimpanzee, Pan troglodytes troglodytes, 10 sequences; Western chimpanzee, Pan troglodytes verus, 6 sequences; Nigeria-Cameroon chimpanzee, Pan troglodytes ellioti, 4 sequences; and Eastern chimpanzee, Pan troglodytes schweinfurthii, 4 sequences. They were all sequenced to a mean of 25-fold coverage per individual.
The research showed considerable genome diversity in chimpanzees
with many population-specific traits. The central chimpanzees retain the
highest diversity in the chimpanzee lineage, whereas the other
subspecies demonstrate signs of population bottlenecks.
Background
Human and chimpanzeechromosomes are very alike. The primary difference is that humans have one fewer pair of chromosomes than do other great apes.
Humans have 23 pairs of chromosomes and other great apes have 24 pairs
of chromosomes. In the human evolutionary lineage, two ancestral ape
chromosomes fused at their telomeres, producing human chromosome 2.
There are nine other major chromosomal differences between chimpanzees
and humans: chromosome segment inversions on human chromosomes 1, 4, 5, 9, 12, 15, 16, 17, and 18. After the completion of the Human genome project, a common chimpanzee
genome project was initiated. In December 2003, a preliminary analysis
of 7600 genes shared between the two genomes confirmed that certain
genes such as the forkhead-box P2transcription factor,
which is involved in speech development, are different in the human
lineage. Several genes involved in hearing were also found to have
changed during human evolution, suggesting selection involving human language-related
behavior. Differences between individual humans and common chimpanzees
are estimated to be about 10 times the typical difference between pairs
of humans.
Another study showed that patterns of DNA methylation, which are a
known regulation mechanism for gene expression, differ in the
prefrontal cortex of humans versus chimpanzees, and implicated this
difference in the evolutionary divergence of the two species.
Chimpanzee-human chromosome differences. A major structural difference is that human chromosome 2 (green color code) was derived from two smaller chromosomes that are found in other great apes (now called 2A and 2B ).
Parts of human chromosome 2 are scattered among parts of several cat
and rat chromosomes in these species that are more distantly related to
humans (more ancient common ancestors; about 85 million years since the
human/rodent common ancestor
A database now exists containing the genetic differences between human and chimpanzee genes, with about thirty-five million single-nucleotide changes, five million insertion/deletion events, and various chromosomalrearrangements. Gene duplications
account for most of the sequence differences between humans and chimps.
Single-base-pair substitutions account for about half as much genetic
change as does gene duplication.
Typical human and chimpanzee homologs of proteins differ in only an average of two amino acids.
About 30 percent of all human proteins are identical in sequence to the
corresponding chimpanzee protein. As mentioned above, gene duplications
are a major source of differences between human and chimpanzee genetic
material, with about 2.7 percent of the genome now representing
differences having been produced by gene duplications or deletions
during approximately 6 million years since humans and chimpanzees diverged from their common evolutionary
ancestor. The comparable variation within human populations is 0.5
percent.
About 600 genes were identified that may have been undergoing
strong positive selection in the human and chimpanzee lineages; many of
these genes are involved in immune system defense against microbial disease (example: granulysin is protective against Mycobacterium tuberculosis) or are targeted receptors of pathogenic microorganisms (example: Glycophorin C and Plasmodium falciparum). By comparing human and chimpanzee genes to the genes of other mammals, it has been found that genes coding for transcription factors, such as forkhead-box P2 (FOXP2),
have often evolved faster in the human relative to chimpanzee;
relatively small changes in these genes may account for the
morphological differences between humans and chimpanzees. A set of 348
transcription factor genes code for proteins with an average of about 50
percent more amino acid changes in the human lineage than in the
chimpanzee lineage.
Six human chromosomal regions were found that may have been under
particularly strong and coordinated selection during the past 250,000
years. These regions contain at least one marker allele
that seems unique to the human lineage while the entire chromosomal
region shows lower than normal genetic variation. This pattern suggests
that one or a few strongly selected genes in the chromosome region may
have been preventing the random accumulation of neutral changes in other
nearby genes. One such region on chromosome 7 contains the FOXP2 gene (mentioned above) and this region also includes the Cystic fibrosis transmembrane conductance regulator
(CFTR) gene, which is important for ion transport in tissues such as
the salt-secreting epithelium of sweat glands. Human mutations in the
CFTR gene might be selected for as a way to survive cholera.
Another such region on chromosome 4 may contain elements regulating the expression of a nearby protocadherin gene that may be important for brain
development and function. Although changes in expression of genes that
are expressed in the brain tend to be less than for other organs (such
as liver) on average, gene expression changes in the brain have been
more dramatic in the human lineage than in the chimpanzee lineage.
This is consistent with the dramatic divergence of the unique pattern
of human brain development seen in the human lineage compared to the
ancestral great ape pattern. The protocadherin-beta gene cluster on
chromosome 5 also shows evidence of possible positive selection.
Results from the human and chimpanzee genome analyses should help
in understanding some human diseases. Humans appear to have lost a
functional Caspase 12 gene, which in other primates codes for an enzyme that may protect against Alzheimer's disease.
Diagramatic representation of the location of the fusion site of chromosomes 2A and 2B and the genes inserted at this location.
The results of the chimpanzee genome project suggest that when
ancestral chromosomes 2A and 2B fused to produce human chromosome 2, no
genes were lost from the fused ends of 2A and 2B. At the site of fusion,
there are approximately 150,000 base pairs of sequence not found in
chimpanzee chromosomes 2A and 2B. Additional linked copies of the
PGML/FOXD/CBWD genes exist elsewhere in the human genome, particularly
near the p end of chromosome 9.
This suggests that a copy of these genes may have been added to the end
of the ancestral 2A or 2B prior to the fusion event. It remains to be
determined if these inserted genes confer a selective advantage.
PGM5P4. The phosphoglucomutase pseudogene of human chromosome 2. This gene is incomplete and doesn't produce a functional transcript.
FOXD4L1. The forkhead box
D4-like gene is an example of an intronless gene. The function of this
gene is not known, but it may code for a transcription control protein.
CBWD2. Cobalamin synthetase is a bacterial enzyme that makes vitamin B12. In the distant past, a common ancestor to mice and apes incorporated a copy of a cobalamin synthetase gene (see: Horizontal gene transfer).
Humans are unusual in that they have several copies of cobalamin
synthetase-like genes, including the one on chromosome 2. It remains to
be determined what the function of these human cobalamin synthetase-like
genes is. If these genes are involved in vitamin B12
metabolism, this could be relevant to human evolution. A major change in
human development is greater post-natal brain growth than is observed
in other apes. Vitamin B12 is important for brain development, and vitamin B12 deficiency during brain development results in severe neurological defects in human children.
WASH2P. Several transcripts of unknown function
corresponding to this region have been isolated. This region is also
present in the closely related chromosome 9p terminal region that
contains copies of the PGML/FOXD/CBWD genes.
The beef hormone controversy or beef hormone dispute is one of the most intractable agricultural trade controversies since the establishment of the World Trade Organization (WTO).
It has sometimes been called the "beef war" in the media, as was the UK–EU beef dispute, creating some confusion, especially when both were occurring.
In 1989, the European Union banned the import of meat that contained artificial beef growth hormones
approved for use and administered in the United States. Originally, the
ban covered six such hormones but was amended in 2003 to permanently
ban one hormone —estradiol-17β — while provisionally banning the use of the five others. WTO rules permit such bans, but only where a signatory presents valid scientific evidence that the ban is a health and safety measure. Canada and the United States opposed this ban, taking the EU to the WTO Dispute Settlement Body. In 1997, the WTO Dispute Settlement Body ruled against the EU.
History
EU ban and its background
The hormones banned by the EU in cattle farming were estradiol, progesterone, testosterone, zeranol, melengestrol acetate and trenbolone acetate. Of these, the first three are synthetic versions of endogenous
hormones that are naturally produced in humans and animals, and also
occur in a wide range of foods, whereas the last two are synthetic and
not naturally occurring, which mimic the behaviour of endogenous
hormones. Zeranol (alpha-zearalanol) is produced semi-synthetically,
but it also occurs naturally in some foods. It is one of several
derivatives of zearalenone produced by certain Fusarium.
Although its occurrence in animal products can be partly due to its
ingestion in such feeds, alpha-zearalanol can also be produced
endogenously in ruminants that have ingested zearalenone and some
zearalenone derivatives in such feeds.
The EU did not impose an absolute ban. Under veterinary supervision,
cattle farmers were permitted to administer the synthetic versions of
natural hormones for cost-reduction and possibly therapeutic purposes,
such as synchronising the oestrus cycles of dairy cows. All six hormones were licensed for use in the US and in Canada.
Under the Agreement on the Application of Sanitary and Phytosanitary Measures,
signatories have the right to impose restrictions on health and safety
grounds subject to scientific analysis. The heart of the Beef Hormone
Dispute was the fact that all risk analysis
is statistical in nature, and thus unable to determine with certainty
the absence of health risks, and consequent disagreement between the US
and Canada beef producers on the one hand, who believed that a broad
scientific consensus existed that beef produced with the use of hormones
was safe, and the EU on the other, which asserted that it was not safe.
The use of these hormones in cattle farming had been studied
scientifically in North America for 50 years prior to the ban, and there
had been widespread long-term use in over 20 countries. Canada and the
United States asserted that this provided empirical evidence both of
long-term safety and of scientific consensus.
The EU ban was not, as it was portrayed to rural constituencies in the US and Canada, protectionism.
The EU had already had other measures that effectively restricted the
import of North American beef. In the main, the North American product
that the new ban affected, which existing barriers did not, was edible
offal.
Consumers expressing concern over the safety of hormone use
pressured EU officials. There were a series of widely publicized
"hormone scandals" in Italy in the late 1970s and early 1980s. The
first, in 1977, was signs of the premature onset of puberty
in northern Italian schoolchildren, where investigators had cast
suspicion in the direction of school lunches that had used meat farmed
with the (illegal) use of growth hormones.
No concrete evidence linking premature puberty to growth hormones was
found, in part because no samples of the suspect meals were available
for analysis. But public anger arose at the use of such meat production
techniques, to be further fanned by the discovery in 1980 of the (again
illegal) presence of diethylstilbestrol (DES), another synthetic hormone, in veal-based baby foods.
The scientific evidence for health risks associated with the use
of growth hormones in meat production was, at best, scant. However,
consumer lobbyist groups were far more able to successfully influence
the European Parliament
to enact regulations in the 1980s than producer lobbyist groups were,
and had far more influence over public perceptions. This is in contrast
with the US at the time, where there was little interest from consumer organizations
in the subject prior to the 1980s, and regulations were driven by a
well-organized coalition of export-oriented industry and farming
interests, who were only opposed by traditional farming groups.
Until 1980, the use of growth hormones, both endogenous and
exogenous, was completely prohibited in (as noted above) Italy, Denmark,
the Netherlands, and Greece. Germany, the largest beef producer in the
EU at the time, prohibited just the use of exogenous growth hormones.
The five other member countries, including the second and third largest
beef producers, France and the United Kingdom, permitted their use.
(The use of growth hormones was particularly common in the U.K., where
beef production was heavily industrialized.) This had resulted in
several disputes amongst member countries, with the countries that had
no prohibitions arguing that the restrictions by the others acted as
non-tariff trade barriers. But in response to the public outcry in
1980, in combination with the contemporary discovery that DES was a teratogen, the EU began to issue regulations, beginning with a directive prohibiting the use of stilbenes and thyrostatics issued by the European Community Council of Agriculture Ministers
in 1980, and the commissioning of a scientific study into the use of
estradiol, testosterone, progesterone, trenbolone, and zeranol in 1981.
The European Consumers' Organisation (BEUC)
lobbied for a total ban upon growth hormones, opposed, with only
partial success, by the pharmaceutical industry, which was not well
organized at the time. (It was not until 1987, at the instigation of US
firms, that the European Federation of Animal Health,
FEDESA, was formed to represent at EU level the companies that, amongst
other things, manufactured growth hormones.) Neither European farmers
nor the meat processing industry took any stance on the matter. With
the help of the BEUC consumer boycotts
of veal products, sparked in Italy by reports about DES in Italian
magazines and in France and Germany by similar reports, spread from
those three countries across the whole of the EU, causing companies such
as Hipp and Alete
to withdraw their lines of veal products, and veal prices to drop
significantly in France, Belgium, West Germany, Ireland, and the
Netherlands. Because of the fixed purchases guaranteed by the EU's Common Agricultural Policy, there was a loss of ECU 10 million to the EU's budget.
The imposition of a general ban was encouraged by the European
Parliament, with a 1981 resolution passing by a majority of 177:1 in
favour of a general ban. MEPs,
having been directly elected for the first time in 1979, were taking
the opportunity to flex their political muscles, and were in part using
the public attention on the issue to strengthen the Parliament's role.
The Council of Ministers was divided along lines that directly matched
each country's domestic stance on growth hormone regulation, with
France, Ireland, the U.K., Belgium, Luxembourg, and Germany all opposing
a general ban. The European Commission,
leery of a veto by the Council and tightly linked to both
pharmaceutical and (via Directorate VI) agricultural interests,
presented factual arguments and emphasized the problem of trade
barriers.
1998 WTO decision
The WTO Appellate Body affirmed the WTO Panel conclusion in a report adopted by the WTO Dispute Settlement Body on 13 February 1998. Section 208 of this report says:
[W]e find that the European Communities did not actually proceed to
an assessment, within the meaning of Articles 5.1 and 5.2, of the risks
arising from the failure of observance of good veterinary practice
combined with problems of control of the use of hormones for growth
promotion purposes. The absence of such risk assessment, when
considered in conjunction with the conclusion actually reached by most,
if not all, of the scientific studies relating to the other aspects of
risk noted earlier, leads us to the conclusion that no risk assessment
that reasonably supports or warrants the import prohibition embodied in
the EC Directives was furnished to the Panel. We affirm, therefore, the
ultimate conclusions of the Panel that the EC import prohibition is not
based on a risk assessment within the meaning of Articles 5.1 and 5.2
of the SPS Agreement and is, therefore, inconsistent with the
requirements of Article 5.1.
In
2002 the EU Scientific Committee on Veterinary Measures relating to
Public Health (SCVPH) claimed that the use of beef growth hormones posed
a potential health risk, and in 2003 the EU enacted Directive 2003/74/EC to amend its ban, but the US and Canada rejected that the EU had met WTO standards for scientific risk assessment.
The EC made the scientific claim that the hormones used in treating cattle remain in the tissue, specifically the hormone 17-beta estradiol.
However, despite this evidence the EC declared there was no clear link
to health risks in humans for the other five provisionally banned
hormones. The EC has also found high amounts of hormones in areas where
there are dense cattle lots. This increase in hormones in the water has
affected waterways and nearby wild fish.
Contamination of North American waterways by hormones would not,
however, have any direct impact on European consumers or their health.
2008 WTO decision
In
November 2004, the EU requested WTO consultations, claiming that the
United States should remove its retaliatory measures since the EU has
removed the measures found to be WTO-inconsistent in the original case.
In 2005, the EU initiated new WTO dispute settlement proceedings
against the United States and Canada, and a March 2008 panel report
cited fault with all three parties (EU, United States, and Canada) on
various substantive and procedural aspects of the dispute.
In October 2008, the WTO Appellate Body issued a mixed ruling that
allows for continued imposition of trade sanctions on the EU by the
United States and Canada, but also allows the EU to continue its ban on
imports of hormone-treated beef.
In November 2008, the EU filed a new WTO challenge following the
announcement by the USTR that it was seeking comment on possible
modification of the list of EU products subject to increased tariffs
under the dispute, and in January 2009 the USTR announced changes to the
list of EU products subject to increased tariffs. In September 2009, the United States and the European Commission
signed a memorandum of understanding, which established a new EU
duty-free import quota for grain-fed, high quality beef (HQB) as part of
a compromise solution.
However, in December 2016, the US took steps to reinstate retaliatory
tariffs on the list of EU products under the dispute given continued
concerns about US beef access to the EU market, and in August 2019 they agreed establishing an initial duty-free tariff-rate quota
of 18,500 tonnes annually, phased over seven years to 35,000 tonnes
(valued at approximately US$420 million) of the EU 45,000 tonnes quota
of non-hormone treated beef.
Effects upon policy in the EU
The EU often applies the precautionary principle
very stringently in regards to food safety. The precautionary principle
means that in a case of scientific uncertainty, the government may take
appropriate measures proportionate to the potential risk (EC Regulation
178/2002). In 1996, the EU banned imported beef from the US and
continued to do so after the 2003 Mad Cow scare. A more sophisticated
risk assessment found there to be insufficient risk to ban certain
hormones, but continued to ban others.
Labeling of meat was another option, however warnings were also
insufficient because of the criteria specified in the SPS (Sanitary and
Phyto-Sanitary agreement). This agreement allows members to use
scientifically based measures to protect public health. Most
specifically the Equivalence provision in Article 4 which states the
following: "an importing country must accept an SPS measure which
differs from its own as equivalent if the exporting country’s measure
provides the same level of health or environmental protection."
Therefore, although the EU is a strong proponent of labels and banning
meat that contains growth hormones, requiring the US to do the same
would have violated this agreement.
Effects upon public opinion in the US
One
of the effects of the Beef Hormone Dispute in the US was to awaken the
public's interest in the issue. This interest was not wholly
unsympathetic to the EU. In 1989, for example, the Consumer Federation of America and the Center for Science in the Public Interest both pressed for an adoption of a ban within the US similar to that within the EU.
US consumers appear to be less concerned with the use of synthetic
chemicals in food production. Because of current policy, in which all
beef is allowed whether produced with hormones or genetically modified,
US consumers now have to rely on their own judgment when buying goods.
However, in a study done in 2002, 85% of respondents wanted mandatory
labeling on beef produced with growth hormones. The public in general is motivated to purchase organic
or natural meats for several reasons. Organic meats and poultry is the
fastest growing agricultural sector; from 2002 to 2003 there was a
growth of 77.8%, accounting for $23 billion in the entire organic food
market.
In animal husbandry, feed conversion ratio (FCR) or feed conversion rate is a ratio or rate measuring of the efficiency with which the bodies of livestock convert animal feed into the desired output. For dairy cows, for example, the output is milk, whereas in animals raised for meat (such as beef cows, pigs, chickens, and fish) the output is the flesh, that is, the body mass gained by the animal, represented either in the final mass of the animal or the mass of the dressed output. FCR is the mass of the input divided by the output (thus mass of feed per mass of milk or meat). In some sectors, feed efficiency, which is the output divided by the input (i.e. the inverse of FCR), is used. These concepts are also closely related to efficiency of conversion of ingested foods (ECI).
Background
Feed
conversion ratio (FCR) is the ratio of inputs to outputs; it is the
inverse of "feed efficiency" which is the ratio of outputs to inputs. FCR is widely used in hog and poultry production, while FE is used more commonly with cattle. Being a ratio the FCR is dimensionless, that is, it is not affected by the units of measurement used to determine the FCR.
FCR a function of the animal's genetics and age, the quality and ingredients of the feed, and the conditions in which the animal is kept, and storage and use of the feed by the farmworkers.
As a rule of thumb, the daily FCR is low for young animals (when
relative growth is large) and increases for older animals (when relative
growth tends to level out). However FCR is a poor basis to use for
selecting animals to improve genetics, as that results in larger animals
that cost more to feed; instead residual feed intake (RFI) is used which is independent of size.
RFI uses for output the difference between actual intake and predicted
intake based on an animal's body weight, weight gain, and composition.
The outputs portion may be calculated based on weight gained, on
the whole animal at sale, or on the dressed product; with milk it may be
normalized for fat and protein content.
As for the inputs portion, although FCR is commonly calculated
using feed dry mass, it is sometimes calculated on an as-fed wet mass
basis, (or in the case of grains and oilseeds, sometimes on a wet mass
basis at standard moisture content), with feed moisture resulting in
higher ratios.
Conversion ratios for livestock
Animals
that have a low FCR are considered efficient users of feed. However,
comparisons of FCR among different species may be of little significance
unless the feeds involved are of similar quality and suitability.
Beef cattle
As of 2013 in the US, an FCR calculated on live weight gain of 4.5–7.5 was in the normal range with an FCR above 6 being typical. Divided by an average carcass yield of 62.2%, the typical carcass weight FCR is above 10. As of 2013
FCRs had not changed much compared to other fields in the prior 30
years, especially compared to poultry which had improved feed efficiency
by about 250% over the last 50 years.
Dairy cattle
The
dairy industry traditionally didn't use FCR but in response to
increasing concentration in the dairy industry and other livestock
operations, the EPA updated its regulations in 2003 controlling manure and other waste releases produced by livestock operators.
In response the USDA began issuing guidance to dairy farmers about how
to control inputs to better minimize manure output and to minimize
harmful contents, as well as optimizing milk output.
In the US, the price of milk is based on the protein and fat content, so the FCR is often calculated to take that into account. Using an FCR calculated just on the weight of protein and fat, as of 2011 an FCR of 13 was poor, and an FCR of 8 was very good.
Another method for dealing with pricing based on protein and fat,
is using energy-corrected milk (ECM), which adds a factor to normalize
assuming certain amounts of fat and protein in a final milk product;
that formula is (0.327 x milk mass) + (12.95 x fat mass) + (7.2 x
protein mass).
In the dairy industry, feed efficiency (ECM/intake) is often used
instead of FCR (intake/ECM); an FE less than 1.3 is considered
problematic.
FE based simply on the weight of milk is also used; an FE between 1.30 and 1.70 is normal.
Pigs
Pigs have been kept to produce meat for 5,000 to 9,000 years. As of 2011,
pigs used commercially in the UK and Europe had an FCR, calculated
using weight gain, of about 1 as piglets and ending about 3 at time of
slaughter. As of 2012
in Australia and using dressed weight for the output, a FCR calculated
using weight of dressed meat of 4.5 was fair, 4.0 was considered "good",
and 3.8, "very good".
The FCR of pigs is greatest up to the period, when pigs weigh 220 pounds. During this period, their FCR is 3.5. Their FCR begins decreasing gradually after this period. For instance, in the US as of 2012,
commercial pigs had FCR calculated using weight gain, of 3.46 for while
they weighed between 240 and 250 pounds, 3.65 between 250 and 260
pounds, 3.87 between 260 and 270 lbs, and 4.09 between 280 and 270 lbs.
Because FCR calculated on the basis of weight gained gets worse
after pigs mature, as it takes more and more feed to drive growth,
countries that have a culture of slaughtering pigs at very high weights,
like Japan and Korea, have poor FCRs.
Sheep
Some data
for sheep illustrate variations in FCR. A FCR (kg feed dry matter intake
per kg live mass gain) for lambs is often in the range of about 4 to 5
on high-concentrate rations, 5 to 6 on some forages of good quality, and more than 6 on feeds of lesser quality. On a diet of straw, which has a low metabolizable energy concentration, FCR of lambs may be as high as 40. Other things being equal, FCR tends to be higher for older lambs (e.g. 8 months) than younger lambs (e.g. 4 months).
Poultry
As of 2011 in the US, broiler chickens has an FCR of 1.6 based on body weight gain, and mature in 39 days. At around the same time the FCR based on weight gain for broilers in Brazil was 1.8. The global average in 2013 is around 2.0 for weight gain (live weight) and 2.8 for slaughtered meat (carcass weight).
For hens used in egg production in the US, as of 2011 the FCR was about 2, with each hen laying about 330 eggs per year.
When slaughtered, the world average layer flock as of 2013 yields a
carcass FCR of 4.2, still much better than the average backyard chicken
flock (FCR 9.2 for eggs, 14.6 for carcass).
From the early 1960s to 2011 in the US broiler growth rates
doubled and their FCRs halved, mostly due to improvements in genetics
and rapid dissemination of the improved chickens.
The improvement in genetics for growing meat created challenges for
farmers who breed the chickens that are raised by the broiler industry,
as the genetics that cause fast growth decreased reproductive abilities.
Carnivorous fish
The FIFO ratio (or Fish In – Fish Out ratio) is a conversion ratio applied to aquaculture,
where the first number is the mass of harvested fish used to feed
farmed fish, and the second number is the mass of the resulting farmed
fish.
FIFO is a way of expressing the contribution from harvested wild fish
used in aquafeed compared with the amount of edible farmed fish, as a
ratio. Fishmeal and fish oil inclusion rates in aquafeeds have shown a
continual decline over time as aquaculture grows and more feed is
produced, but with a finite annual supply of fishmeal and fish oil.
Calculations have shown that the overall fed aquaculture FIFO declined
from 0.63 in 2000 to 0.33 in 2010, and 0.22 in 2015.
In 2015, therefore, approximately 4.55 kg of farmed fish was produced
for every 1 kg of wild fish harvested and used in feed. The fish used
in fishmeal and fish oil production are not used for human consumption,
but with their use as fishmeal and fish oil in aquafeed they contribute
to global food production.
As of 2015 farm raised Atlantic salmon had a commodified feed supply with four main suppliers, and an FCR of around 1. Tilapia is about 1.5, and as of 2013 farmed catfish had a FCR of about 1.
Herbivorous and omnivorous fish
For herbivorous and omnivorous fish like Chinese carp and tilapia,
the plant-based feed yields much lower FCR compared to carnivorous kept
on a partially fish-based diet, despite a decrease in overall resource
use. The edible (fillet) FCR of tilapia is around 4.6 and the FCR of
Chinese carp is around 4.9.
Rabbits
In
India, rabbits raised for meat had an FCR of 2.5 to 3.0 on high grain
diet and 3.5 to 4.0 on natural forage diet, without animal-feed grain.
Global averages by species and production systems
In a global study published in the journal Global Food Security, FAO estimated various feed conversion ratios, taking into account the diversity of feed material consumed by livestock. At global level, ruminants require 133 kg of dry matter per kg of protein while monograstrics require 30. However, when considering human edible feed only, ruminants require 5.9
kg of feed to produce 1 kg of animal protein, while monogatrsics
require 15.8 kg.
When looking at meat only, ruminants consume an average of 2.8 kg of
human edible feed per kg of meat produced, while monogastrics need 3.2.
Finally, when accounting for the protein content of the feed, ruminant
need an average of 0.6 kg of edible plant protein to produce 1 kg of
animal protein while monogastric need 2. This means that ruminants make a positive net contribution to the supply of edible protein for humans at global level.
Feed conversion ratios of meat alternatives
Many alternatives to conventional animal meat sources have been proposed for higher efficiency, including insects, meat analogues, and cultured meats.
Insects
Although there are few studies of the feed conversion ratios of edible insects, the house cricket (Acheta domesticus) has been shown to have a FCR of 0.9 - 1.1 depending on diet composition.
A more recent work gives an FCR of 1.9–2.4. Reasons contributing to
such a low FCR include the whole body being used for food, the lack of
internal temperature control (insects are poikilothermic), high fecundity and rate of maturation.
Meat analogue
If one treats tofu as a meat, the FCR reaches as low as 0.29. The FCRs for less watery forms of meat analogues are unknown.
Cultured meat
Although cultured meat
has a potentially much lower land footprint required, its FCR is closer
to poultry at around 4 (2-8). It has a high need for energy inputs.
The meat industry are the people and companies engaged in modern industrialized livestock agriculture for the production, packing, preservation and marketing of meat (in contrast to dairy products, wool, etc.). In economics,
the meat industry is a fusion of primary (agriculture) and secondary
(industry) activity and hard to characterize strictly in terms of either
one alone. The greater part of the meat industry is the meat packing industry – the segment that handles the slaughtering, processing, packaging, and distribution of animals such as poultry, cattle, pigs, sheep and other livestock.
The meat industry in 2013
A great portion of the ever-growing meat branch in the food industry involves intensive animal farming in which livestock are kept almost entirely indoors or in restricted outdoor settings like pens. Many aspects of the raising of animals for meat have become industrialized, even many practices more associated with smaller family farms, e.g. gourmet foods such as foie gras. The production of livestock is a heavily vertically integrated industry where the majority of supply chain stages are integrated and owned by one company.
animal diseases, e.g. mad-cow disease (BSE), avian flu, swine influenza (H1N1), avian influenza (H5N1), foot-and-mouth disease, some of which can spread to human consumers
climate change via greenhouse gases
generated by the meat industry is significantly greater than growing
and processing fruits and vegetables. The largest agricultural methane
source on the planet is livestock. Global greenhouse gas emissions from
animal-based foods are twice those of plant-based foods.
Many observers suggest that the expense of dealing with the above is grossly underestimated at present economic metrics and that true/full cost accounting would drastically raise the price of industrial meat.
Effects on livestock workers
American slaughterhouse workers are three times more likely to suffer serious injury than the average American worker. NPR
reports that pig and cattle slaughterhouse workers are nearly seven
times more likely to suffer repetitive strain injuries than average. The Guardian reports that, on average, there are two amputations a week involving slaughterhouse workers in the United States. On average, one employee of Tyson Foods, the largest meat producer in America, is injured and amputates a finger or limb per month. The Bureau of Investigative Journalism reported that over a period of six years, in the UK
78 slaughter workers lost fingers, parts of fingers or limbs, more than
800 workers had serious injuries, and at least 4,500 had to take more
than three days off after accidents.
In a 2018 study in the Italian Journal of Food Safety, slaughterhouse
workers are instructed to wear ear protectors to protect their hearing
from the constant screams of animals being killed.
A 2004 study in the Journal of Occupational and Environmental Medicine
found that "excess risks were observed for mortality from all causes,
all cancers, and lung cancer" in workers employed in the New Zealand
meat processing industry.
The worst thing, worse than the
physical danger, is the emotional toll. If you work in the stick pit
[where hogs are killed] for any period of time—that let's [sic] you kill
things but doesn't let you care. You may look a hog in the eye that's
walking around in the blood pit with you and think, 'God, that really
isn't a bad looking animal.' You may want to pet it. Pigs down on the
kill floor have come up to nuzzle me like a puppy. Two minutes later I
had to kill them – beat them to death with a pipe. I can't care.
— Gail A. Eisnitz,
The act of slaughtering animals, or of raising or transporting
animals for slaughter, may engender psychological stress or trauma in
the people involved. A 2016 study in Organization
indicates, "Regression analyses of data from 10,605 Danish workers
across 44 occupations suggest that slaughterhouse workers consistently
experience lower physical and psychological well-being along with
increased incidences of negative coping behavior."
A 2009 study by criminologist Amy Fitzgerald indicates, "slaughterhouse
employment increases total arrest rates, arrests for violent crimes,
arrests for rape, and arrests for other sex offenses in comparison with
other industries."
As authors from the PTSD Journal explain, "These employees are hired to
kill animals, such as pigs and cows, that are largely gentle creatures.
Carrying out this action requires workers to disconnect from what they
are doing and from the creature standing before them. This emotional
dissonance can lead to consequences such as domestic violence, social
withdrawal, anxiety, drug and alcohol abuse, and PTSD."
Slaughterhouses in the United States commonly illegally employ and exploit underage workers and illegal immigrants. In 2010, Human Rights Watch described slaughterhouse line work in the United States as a human rights crime. In a report by Oxfam America,
slaughterhouse workers were observed not being allowed breaks, were
often required to wear diapers, and were paid below minimum wage.
Possible alternatives
Cultured meat
(aka "clean meat") potentially offers some advantages in terms of
efficiency of resource use and animal welfare. It is, however, still at
an early stage of development and its advantages are still contested.
Increasing health care costs for an aging baby boom population suffering from obesity
and other food-related diseases, concerns about obesity in children
have spurred new ideas about healthy nutrition with less emphasis on
meat.
Native wild species like deer and bison in North America would be cheaper and potentially have less impact on the environment. The combination of more wild game meat options and higher costs for natural capital affected by the meat industry could be a building block towards a more sustainable livestock agriculture.
A growing trend towards vegetarian or vegan diets and the Slow Food movement are indicators of a changing consumer conscience in western countries. Producers on the other hand have reacted to consumer concerns by slowly shifting towards ecological or organic farming. The Alternative meat industry is projected to be worth 140 billion in the next 10 years.
Slaughterhouses that produce meat that is not intended for human consumption are sometimes referred to as knacker's yards or knackeries.
This is where animals are slaughtered that are not fit for human
consumption or that can no longer work on a farm, such as retired work horses.
Slaughtering animals on a large scale poses significant issues in terms of logistics, animal welfare, and the environment, and the process must meet public health
requirements. Due to public aversion in different cultures, determining
where to build slaughterhouses is also a matter of some consideration.
Frequently, animal rights
groups raise concerns about the methods of transport to and from
slaughterhouses, preparation prior to slaughter, animal herding, and the
killing itself.
Until modern times, the slaughter of animals generally took place in a
haphazard and unregulated manner in diverse places. Early maps of
London show numerous stockyards in the periphery of the city, where slaughter occurred in the open air or under cover such as wet markets. A term for such open-air slaughterhouses was shambles, and there are streets named "The Shambles" in some English and Irish towns (e.g., Worcester, York, Bandon) which got their name from having been the site on which butchers killed and prepared animals for consumption. Fishamble Street, Dublin was formerly a fish-shambles. Sheffield had 183 slaughterhouses in 1910, and it was estimated that there were 20,000 in England and Wales.
Reform movement
The slaughterhouse emerged as a coherent institution in the 19th century. A combination of health and social concerns, exacerbated by the rapid urbanisation experienced during the Industrial Revolution, led social reformers
to call for the isolation, sequester and regulation of animal
slaughter. As well as the concerns raised regarding hygiene and disease,
there were also criticisms of the practice on the grounds that the
effect that killing had, both on the butchers and the observers,
"educate[d] the men in the practice of violence and cruelty, so that
they seem to have no restraint on the use of it."
An additional motivation for eliminating private slaughter was to
impose a careful system of regulation for the "morally dangerous" task
of putting animals to death.
As a result of this tension, meat markets within the city were closed
and abattoirs built outside city limits. An early framework for the
establishment of public slaughterhouses was put in place in Paris in
1810, under the reign of the Emperor Napoleon. Five areas were set aside on the outskirts of the city and the feudal privileges of the guilds were curtailed.
As the meat requirements of the growing number of residents in London steadily expanded,
the meat markets both within the city and beyond attracted increasing levels of public disapproval. Meat had been traded at Smithfield Market as early as the 10th century. By 1726, it was regarded as "without question, the greatest in the world", by Daniel Defoe.
By the middle of the 19th century, in the course of a single year
220,000 head of cattle and 1,500,000 sheep would be "violently forced
into an area of five acres, in the very heart of London, through its
narrowest and most crowded thoroughfares".
By the early 19th century, pamphlets were being circulated arguing in
favor of the removal of the livestock market and its relocation outside
of the city due to the extremely low hygienic conditions as well as the brutal treatment of the cattle. In 1843, the Farmer's Magazine
published a petition signed by bankers, salesmen, aldermen, butchers
and local residents against the expansion of the livestock market. The Town Police Clauses Act 1847 created a licensing and registration system, though few slaughter houses were closed.
An Act of Parliament was eventually passed in 1852. Under its provisions, a new cattle-market was constructed in Copenhagen Fields, Islington. The new Metropolitan Cattle Market
was also opened in 1855, and West Smithfield was left as waste ground
for about a decade, until the construction of the new market began in
the 1860s under the authority of the 1860 Metropolitan Meat and Poultry
Market Act. The market was designed by architect Sir Horace Jones and was completed in 1868.
A cut and cover railway tunnel was constructed beneath the market to create a triangular junction with the railway between Blackfriars and King's Cross.
This allowed animals to be transported into the slaughterhouse by train
and the subsequent transfer of animal carcasses to the Cold Store
building, or direct to the meat market via lifts.
At the same time, the first large and centralized slaughterhouse in Paris was constructed in 1867 under the orders of Napoleon III at the Parc de la Villette and heavily influenced the subsequent development of the institution throughout Europe.
Regulation and expansion
Blueprint for a mechanized public abattoir, designed by slaughterhouse reformer Benjamin Ward Richardson
These slaughterhouses were regulated by law to ensure good standards
of hygiene, the prevention of the spread of disease and the minimization
of needless animal cruelty. The slaughterhouse had to be equipped with a
specialized water supply system to effectively clean the operating area
of blood and offal. Veterinary scientists, notably George Fleming and John Gamgee, campaigned for stringent levels of inspection to ensure that epizootics such as rinderpest
(a devastating outbreak of the disease covered all of Britain in 1865)
would not be able to spread. By 1874, three meat inspectors were
appointed for the London area, and the Public Health Act 1875
required local authorities to provide central slaughterhouses (they
were only given powers to close unsanitary slaughterhouses in 1890).
Yet the appointment of slaughterhouse inspectors and the establishment
of centralised abattoirs took place much earlier in the British
colonies, such as the colonies of New South Wales and Victoria, and in
Scotland where 80% of cattle were slaughtered in public abattoirs by
1930. In Victoria the Melbourne Abattoirs Act 1850 (NSW)
"confined the slaughtering of animals to prescribed public abattoirs,
while at the same time prohibiting the killing of sheep, lamb, pigs or
goats at any other place within the city limits".
Animals were shipped alive to British ports from Ireland, from Europe
and from the colonies and slaughtered in large abattoirs at the ports.
Conditions were often very poor.
Attempts were also made throughout the British Empire to reform
the practice of slaughter itself, as the methods used came under
increasing criticism for causing undue pain to the animals. The eminent
physician, Benjamin Ward Richardson,
spent many years in developing more humane methods of slaughter. He
brought into use no fewer than fourteen possible anesthetics for use in
the slaughterhouse and even experimented with the use of electric
current at the Royal Polytechnic Institution. As early as 1853, he designed a lethal chamber that would gas animals to death relatively painlessly, and he founded the Model Abattoir Society in 1882 to investigate and campaign for humane methods of slaughter.
The invention of refrigeration
and the expansion of transportation networks by sea and rail allowed
for the safe exportation of meat around the world. Additionally,
meat-packing millionaire Philip Danforth Armour's invention of the "disassembly line" greatly increased the productivity and profit margin of the meat packing industry: "according to some, animal slaughtering became the first mass-production
industry in the United States." This expansion has been accompanied by
increased concern about the physical and mental conditions of the
workers along with controversy over the ethical and environmental
implications of slaughtering animals for meat.
The Edinburgh abattoir, which was built in 1910, had well lit
laboratories, hot and cold water, gas, microscopes and equipment for
cultivating organisms. The English 1924 Public Health (Meat) Regulations
required notification of slaughter to enable inspection of carcasses
and enabled inspected carcasses to be marked.
The development of slaughterhouses was linked with industrial
expansion of by-products. By 1932 the British by-product industry was
worth about £97 million a year, employing 310,000 people. The Aberdeen
slaughterhouse sent hooves to Lancashire to make glue, intestines to
Glasgow for sausages and hides to the Midland tanneries.
In January 1940 the British government took over the 16,000
slaughterhouses and by 1942 there were only 779.
Design
Slaughterhouse waste
In the latter part of the 20th century, the layout and design of most U.S. slaughterhouses was influenced by the work of Temple Grandin.
She suggested that reducing the stress of animals being led to
slaughter may help slaughterhouse operators improve efficiency and
profit. In particular she applied an understanding of animal psychology to design pens and corrals
which funnel a herd of animals arriving at a slaughterhouse into a
single file ready for slaughter. Her corrals employ long sweeping curves
so that each animal is prevented from seeing what lies ahead and just
concentrates on the hind quarters of the animal in front of it. This
design – along with the design elements of solid sides, solid crowd
gate, and reduced noise at the end point – work together to encourage
animals forward in the chute and to not reverse direction.
Mobile design
Beginning
in 2008 the Local Infrastructure for Local Agriculture, a non-profit
committed to revitalizing opportunities for "small farmers and
strengthening the connection between local supply and demand",
constructed a mobile slaughterhouse facility in efforts for small
farmers to process meat quickly and cost effectively. Named the Modular
Harvest System, or M.H.S., it received USDA
approval in 2010. The M.H.S. consists of three separate trailers: One
for slaughtering, one for consumable body parts, and one for other body
parts. Preparation of individual cuts is done at a butchery or other
meat preparation facility.
The standards and regulations governing slaughterhouses vary
considerably around the world. In many countries the slaughter of
animals is regulated by custom and tradition rather than by law. In the
non-Western world, including the Arab world, the Indian sub-continent, etc., both forms of meat are available: one which is produced in modern mechanized slaughterhouses, and the other from local butcher shops.
In some communities animal slaughter and permitted species may be controlled by religious laws, most notably halal for Muslims and kashrut for Jewish
communities. This can cause conflicts with national regulations when a
slaughterhouse adhering to the rules of religious preparation is located
in some Western countries.
In Jewish law, captive bolts and other methods of pre-slaughter
paralysis are generally not permissible, due to it being forbidden for
an animal to be stunned prior to slaughter. Various halal food
authorities have more recently permitted the use of a recently developed
fail-safe system of head-only stunning
where the shock is non-fatal, and where it is possible to reverse the
procedure and revive the animal after the shock. The use of electronarcosis
and other methods of dulling the sensing has been approved by the
Egyptian Fatwa Committee. This allows these entities to continue their
religious techniques while keeping accordance to the national
regulations.
In some societies, traditional cultural and religious aversion to slaughter led to prejudice against the people involved. In Japan, where the ban on slaughter of livestock for food was lifted in the late 19th century, the newly found slaughter industry drew workers primarily from villages of burakumin, who traditionally worked in occupations relating to death (such as executioners and undertakers). In some parts of western Japan, prejudice faced by current and former residents of such areas (burakumin "hamlet people") is still a sensitive issue. Because of this, even the Japanese word for "slaughter" (屠殺 tosatsu) is deemed politically incorrect by some pressure groups as its inclusion of the kanji for "kill" (殺) supposedly portrays those who practise it in a negative manner.
Some countries have laws that exclude specific animal species or
grades of animal from being slaughtered for human consumption,
especially those that are taboo food. The former Indian Prime MinisterAtal Bihari Vajpayee suggested in 2004 introducing legislation banning the slaughter of cows throughout India, as Hinduism holds cows as sacred
and considers their slaughter unthinkable and offensive. This was often
opposed on grounds of religious freedom. The slaughter of cows and the
importation of beef into the nation of Nepal are strictly forbidden.
Freezing works
Refrigeration
technology allowed meat from the slaughterhouse to be preserved for
longer periods. This led to the concept as the slaughterhouse as a
freezing works. Prior to this, canning was an option.
Freezing works are common in New Zealand, Australia and South Africa.
In countries where meat is exported for a substantial profit the
freezing works were built near docks, or near transport infrastructure.
Mobile poultry processing units (MPPUs) follow the same
principles, but typically require only one trailer and, in much of the
United States, may legally operate under USDA exemptions not available
to red meat processors. Several MPPUs have been in operation since before 2010, under various models of operation and ownership.
Most countries have laws in regard to the treatment of animals in slaughterhouses. In the United States, there is the Humane Slaughter Act
of 1958, a law requiring that all swine, sheep, cattle, and horses be
stunned unconscious with application of a stunning device by a trained
person before being hoisted up on the line. There is some debate over
the enforcement of this act. This act, like those in many countries,
exempts slaughter in accordance to religious law, such as koshershechita and dhabiha halal. Most strict interpretations of kashrut require that the animal be fully sensible when its carotid artery is cut.
The novel The Jungle
presented a fictionalized account of unsanitary conditions in
slaughterhouses and the meatpacking industry during the 1800s. This led
directly to an investigation commissioned directly by President Theodore Roosevelt, and to the passage of the Meat Inspection Act and the Pure Food and Drug Act of 1906, which established the Food and Drug Administration. A much larger body of regulation deals with the public health and worker safety regulation and inspection.
In 1997, Gail Eisnitz, chief investigator for the Humane Farming Association (HFA), released the book Slaughterhouse.
Within, she unveils the interviews of slaughterhouse workers in the
U.S. who say that, because of the speed with which they are required to
work, animals are routinely skinned while apparently alive and still
blinking, kicking and shrieking. Eisnitz argues that this is not only
cruel to the animals but also dangerous for the human workers, as cows
weighing several thousands of pounds thrashing around in pain are likely
to kick out and debilitate anyone working near them.
This would imply that certain slaughterhouses throughout the
country are not following the guidelines and regulations spelled out by
the Humane Slaughter Act,
requiring all animals to be put down and thus insusceptible to pain by
some form, typically electronarcosis, before undergoing any form of
violent action.
According to the HFA, Eiznitz interviewed slaughterhouse workers
representing over two million hours of experience, who, without
exception, told her that they have beaten, strangled, boiled and
dismembered animals alive or have failed to report those who do. The
workers described the effects the violence has had on their personal
lives, with several admitting to being physically abusive or taking to
alcohol and other drugs.
The HFA alleges that workers are required to kill up to 1,100
hogs an hour and end up taking their frustration out on the animals. Eisnitz interviewed one worker, who had worked in ten slaughterhouses, about pig production. He told her:
Hogs get stressed out pretty easy.
If you prod them too much, they have heart attacks. If you get a hog in
the chute that's had the shit prodded out of him and has a heart attack
or refuses to move, you take a meat hook and hook it into his bunghole. You try to do this by clipping the hipbone.
Then you drag him backwards. You're dragging these hogs alive, and a
lot of times the meat hook rips out of the bunghole. I've seen hams –
thighs – completely ripped open. I've also seen intestines come out. If
the hog collapses near the front of the chute, you shove the meat hook
into his cheek and drag him forward.
American slaughterhouse workers are three times more likely to suffer serious injury than the average American worker. NPR
reports that pig and cattle slaughterhouse workers are nearly seven
times more likely to suffer repetitive strain injuries than average. The Guardian reports that on average there are two amputations a week involving slaughterhouse workers in the United States. On average, one employee of Tyson Foods, the largest meat producer in America, is injured and amputates a finger or limb per month. The Bureau of Investigative Journalism reported that over a period of six years, in the UK
78 slaughter workers lost fingers, parts of fingers or limbs, more than
800 workers had serious injuries, and at least 4,500 had to take more
than three days off after accidents.
In a 2018 study in the Italian Journal of Food Safety, slaughterhouse
workers are instructed to wear ear protectors to protect their hearing
from the loud noises in the facility. A 2004 study in the Journal of Occupational and Environmental Medicine
found that "excess risks were observed for mortality from all causes,
all cancers, and lung cancer" in workers employed in the New Zealand
meat processing industry.
The worst thing, worse than the
physical danger, is the emotional toll. If you work in the stick pit
[where hogs are killed] for any period of time – that lets you kill
things but doesn't let you care. You may look a hog in the eye that's
walking around in the blood pit with you and think, "God, that really
isn't a bad looking animal." You may want to pet it. Pigs down on the
kill floor have come up to nuzzle me like a puppy. Two minutes later I
had to kill them – beat them to death with a pipe. I can't care.
— Gail A. Eisnitz,
Working at slaughterhouses often leads to a high amount of psychological trauma. A 2016 study in Organization
indicates, "Regression analyses of data from 10,605 Danish workers
across 44 occupations suggest that slaughterhouse workers consistently
experience lower physical and psychological well-being along with
increased incidences of negative coping behavior."
A 2009 study by criminologist Amy Fitzgerald indicates, "slaughterhouse
employment increases total arrest rates, arrests for violent crimes,
arrests for rape, and arrests for other sex offenses in comparison with
other industries."
As authors from the PTSD Journal explain, "These employees are hired to
kill animals, such as pigs and cows that are largely gentle creatures.
Carrying out this action requires workers to disconnect from what they
are doing and from the creature standing before them. This emotional
dissonance can lead to consequences such as domestic violence, social
withdrawal, anxiety, drug and alcohol abuse, and PTSD."
Starting in the 1980s, Cargill, Conagra Brands, Tyson Foods and other large food companies moved most slaughterhouse operations to rural areas of the Southern United States which were more hostile to unionization efforts. Slaughterhouses in the United States commonly illegally employ and exploit underage workers and undocumented immigrants. In 2010, Human Rights Watch described slaughterhouse line work in the United States as a human rights crime. In a report by Oxfam America,
slaughterhouse workers were observed not being allowed breaks, were
often required to wear diapers, and were paid below minimum wage.
