The Poultry Informed Professional is published with support from The Primary Breeders Veterinary Association by the Department of Population Health of The University of Georgia College of
Veterinary Medicine. © 1999 Board of regents of the University System of Georgia except for: United States Government Publications: “Livestock, Dairy and Poultry Situation and Outlook” (Economic
Research Service, USDA); “Broiler Hatchery” and “Chicken and Eggs” (National Agricultural Statistics Service, Agricultural Statistics Board, U.S.D.A.)© 2009 Primary Breeders Veterinary Association.
Articles may be reprinted with permission. For information and permission to reprint, contact Diane Baird, (706) 542-1904
Issue 107
July/August 2009
®
Published by the Department
of Population Health, University of Georgia
Editor: Dr Stephen Collett, Assistant Professor
Co-Editor: Dr Pedro Villegas, Professor
Department of Population Health
Phone (706) 542-1904
Fax (706) 542-5630
e-mail: dsbaird@uga.edu
Which came first: the egg or its microbiota?
Adriana A. Pedrosa
University of Georgia, Athens, Georgia
Traditional thinking has always led us to believe that the developing embryo is sterile, but Dr Adriana Pedrosa,
a post doctoral student in Dr Margie Lee’s lab has bravely, and successfully challenged that dogma. Not only did
they discover that the embryo intestinal tract is far from sterile but this pioneer microbial community demonstrates
signs of evolution in the last 4-5 days before hatch. In this issue of the PIP they share some of their findings.
Broiler
Live Production Cost
Contents
Gut Microbiota in the Embryo?
1-4
Excerpts. “Broiler Hatchery”
“Chicken and Eggs” and Turkey
Hatchery...
5
Broiler performance data
(Company) Previous month
6
Meetings, Seminars and Conventions
7
Feed Cost/ton w/o color ($)
Feed cost /lb meat (c)
Days to 4.6 lbs
Chick cost / lb (c)
Vac-Med cost/lb (c)
WB & ½ parts condemn. Cost/lb
% mortality
Sq.Ft. @ placement
Lbs/sq. ft.
Downtime (days)
Data for week ending 30 May 2009
Page 1
Average Company
275.97
25.09
41
4.92
0.06
0.18
3.92
0.84
6.88
15
Synopsis
The conventional understanding has long been that birds acquire the intestinal bacteria from
their environment, so newly-hatched chicks are devoid of intestinal microorganisms. However, what if
our assumptions are incorrect, and the intestine is already seeded with bacteria prior to the chick’s
emergence from the egg? Several papers describe the presence of pathogenic microorganisms within
the egg. If this is true, is it not plausible that microorganisms found inside fertile eggs could be part of
chick’s intestinal microbiota, even before hatch? The assumption that chicks hatch germ free were built
on past studies using culture-based approach to characterizing poultry microflora. Studies on the composition of the intestinal microbiota of chickens date back to 1901. It was not until 1940s that researchers were first able to cultivate bacteria from the intestine and was not until the 1970s that artificial media were used to differentiate and enumerate components of the intestinal microflora. Actually, many of
the intestinal bacteria are still impossible to be cultivated. Realizing this, microbial ecologists have
adapted molecular techniques to characterize the chicken intestinal microbiota. These molecular tools
have also contributed greatly to our understanding of the microbial colonization dynamics of the developing chicken intestine and lead us to pose the question: which came first, the egg or its microbiota?
Importance of the chicken microbiota
The microbiota of the intestinal tract of chickens plays an important role in preventing the establishment of intestinal pathogens (Zhu et al., 2002). The gastrointestinal (GI) microbiota represents the
most active defense barrier on the GI tract against microbial invaders. Many growth promoter additives
are used in chicken diets to positively alter the microbial balance (Reid et al., 2006). However, in many
instances these additives have little effect on the microbial composition of the GI tract (Menten &
Pedroso, 2005) to promote good intestinal health (Saier & Mansour, 2005), or efficaciously prevent
zoonotic pathogens from colonizing poultry (Takahashi et al., 2005). The GI microbiota can be manipulated to improve bird performance and animal health, but it requires that we know the composition of
microflora. Actual knowledge about intestinal microbial manipulation is scarce (Bienenstock et al.,
2002); however, recent data suggest the importance of the early establishment of bacterial communities
in preventing colonization of the GI tract by pathogenic bacteria (Hume et al, 1998; Bielke et al., 2003).
At which point does the chick microbiota establish itself?
Some authors believe that at hatch, the chicks may have an intestinal tract devoid of microorganisms
(Forbes & Park, 1958; Kubena et al., 1999; van der Wielen et al., 2002; Amit-Romach et al., 2004,
Maiorka et al., 2006, Apajalahti & Kettunen, 2006) and their intestinal microbiota may be acquired from
the animal’s rearing environment (Lev & Brigs, 1956; Williams, 1978, Mead, 1989, Bailey et al., 1994,
Mitchell et al., 2002, Dibner et al., 2008). On the other hand, research indicates that microorganisms
may colonize the gastrointestinal tract prior to the chick’s emergence from the egg (Loeken & Roth,
1983; Rose et al., 1974, Klasing 1998). It is a paradox. It is recognized that microorganisms on the eggshell surface are able to reach the albumen and yolk (Cook et al., 2002), and is probable that these microorganisms go on to make up the chicks’ microflora. Microbiota may become established in the intestine during the early stages of embryo development as the GI tract differentiates and closes, or in later
stages of development (15 days), through ingestion of the amnion fluid (Klasing 1998). Microorganisms
Page 2Page 2
present in the yolk could also be internalized at the 18th day of development as the yolk sac becomes
internalized (Deeming, 2005).
What is the source of the chick microbiota?
Although the eggshell is considered a barrier against microorganisms, the eggshell surface can
be a microbial source (Mine et al., 2003). The nest is possibly the primary point of microbial acquisition
(Bruce et al., 1991), where the eggshell microbiota may rapidly penetrate the egg (Cook et al., 2003).
During incubation in the hatchery cabinet, the egg contamination can be high (Cox et al., 1991), and
chicks can emerge contaminated (Cason et al., 1994). Microbial vertical transmission from breeder to
chick is also described. Salmonella, Escherichia coli, Mycoplasma, Campylobacter have recognized capacity of vertical transmission from breeders (Robert et al., 1998). They represent important pathogens
and are the focus of a massive amount of work (Okamura et al., 2007, Doyle and Erickson, 2006, Methner et al., 1995, Donaghue et al., 2004); but can healthy bacteria be vertically transmitted too? Probably
yes, but these species have not been researched because they do not represent a public health concern.
Our research at the Poultry Diagnostic and Research Center
To elucidate at which point the bacterial colonization begins, our research team has applied a
molecular ecological approach in our attempts to better understand the microbial colonization dynamics
of the intestinal tract of the developing chicken. Using a toolkit that includes PCR to analyze the diversity of bacteria, fluorescence in situ hybridization (FISH) to visualize specific bacterial species, dyes to
reveal bacterial viability, green fluorescent protein marked Salmonella to reveal colonization dynamics,
we seek to elucidate the mechanisms of vertical transmission of the intestinal microbiota.
Live/dead stain applied to cecal content of an 18-dayold embryo to visualize
the presence of live bacterial cell (at the point of the white arrow).
Page
Page
3 3
Microscopic and molecular evaluation showed a viable and morphologically diverse bacteria
community within embryos’ intestines since day 16 of incubation. It is plausible to believe that the intestinal microbiota is vertically transferred as well from breeder to chicken embryos during egg formation.
Another possibility is the microflora transmission through the eggshell during the laying posture and
incubation process. The cuticle that protects the egg against bacterial penetration and antibacterial components in the egg white suffer degradation (Gast and Holt, 2000), and the eggshell pore is a way for
bacteria to penetrate the egg (Messens et al., 2007). Perhaps, a beneficial microbiota is not able to compromise the embryo’s development or cause their death, and they become incorporated in the embryos’
intestine as this organ and the animal develops.
The concept of germ-free chicks was established around 1950 (Reyniers et al., 1950), when molecular techniques were not available to detect bacteria that were difficult to cultivate. As samples collected from chicks’ intestines did not grow in artificial media, researchers concluded that chicks hatched
with no “germs” in their intestines. However, the chick microbiota has just now been revisited and restudied since the availability of modern molecular techniques. Probably, another mistake is to presume
that the intestinal colonization by microorganisms in birds is similar to the intestinal colonization in
mammalians; which occur after the neonate’s birth. Probably the acquisition of intestinal microbiota by
birds is more similar to the mechanism exhibited by insects, where the phenomena of vertical transmission is well reported and is considered part of the normal developmental cycle (Braendle et al., 2003,
Dillon and Dillon, 2004, Frydman et al., 2006, Shinzato et al., 2007).
The chick microbiota came first
This finding raises opportunities to promote better poultry performance of poultry and to reduce
the risk of foodborne diseases. Establishing an intestinal community of healthy bacteria in the pre-hatch
phase in chicks should make it more difficult for pathogens establish themselves, cause disease or affect
chicken growth rate. We think that the chick’s microbiota can be safely implanted in ovo resulting in
lowered rates of Salmonella carriage and improved intestinal development.
References
Amit-Romach E et al. 2004. Poult. Scie. 83:1093-1098.
Apajalahti J, and Kettunen A. 2006. Avian Gut Function in Health and Disease. Carfax Publ. Co.
Bailey et al. 1994. Poult Sci. 73:1153-1157.
Bielke LR et al. 2003. Poult. Sci. 82:1378-1382.
Bienenstock J et al. 2002. Clin. Rev. Allergy Immunol. 22:275-286.
Braendle C et al. 2003. PLOS Biology. 1:70-76.
Bruce J, and Drysdale EM. 1994. Microbiology of the avian egg. London: Chapman & Hall.
Cason JA et al. 1994. Avian Dis. 38:583-588.
Cook N et al. 2002. J Food Prot. 65:1177-1178
Cook MI et al. 2003. Proc. Biol. Sci. 7:2233-2240.
Cox NA et al. 1991. Poult Sci. 70:416-418.
Deeming DC. 2005. Br. Poult. Sci. 46:560-564.
Dibner JJ et al. 2008. J. Appl. Poult. Res. 17:174-188
Dillon RJ, and VM Dillon. 2004. Annu. Rev. Entomol. 49:71-92.
Page 4
Donoghue AM et al. 2004. Poult. Sci. 83:1728–1733.
Doyle MP, and Erickson MC. 2006. Poult Sci. 85:960-973.
Forbers M, and Park J. 1958. J. Nut. 66:69-84.
Frydman HM et al. 2003. Nature. 441:509-512.
Gast RK, and Holt PS. 2000. Poult Sci. 79:559-563.
Hume ME et al. J. Food Prot. 61:673-676.
Klasing K C. 1998. Comparative Avian Nutrition. Cab International.
Kubena LF et al. Poult. Sci. 1999. suppl:84.
Lev M, and Briggs CAE. 1956. J. Appl. Bac. 19:36-38.
Loeken MR, and Roth TF. 1983. Immunology. 49:21-28.
Maiorka A et al. 2006. Ciência Rural. 36:701-708.
Mead GC. 1989. J. Exp. Zool. Suppl. 3:48-54.
Menten JFM, and Pedroso AA. 2005. Factors that affect the probiotic efficiency. FACTA.
Messens W et al. 2007. J Food Prot. 2007 70:623-628.
Methner U et al. 1995. J. Vet. Med. Ser. B 42:459–469.
Mine Y et al. 2003. J. Agric. Food Chem. 51:249-253.
Mitchell BW 2002. Poult. Sci. 1: 49-55.
Okamura M et al. 2007. Vaccine. 15:4837-4844.
Reid G et al. 2006. FEMS Immunol. Med. Microbiol. 46:149-157.
Reyniers JA et al. 1950. J. Nutrition. 32:31-49.
Robert TA et al. 1998. Microbial ecology of food commodities. ICMSF.
Rose ME et al. 1974. Eur. J. Immunol. 4:521-523.
Saier MH Jr, and Mansour NM. 2005. J. Mol. Microbiol. Biotechnol. 10:22-25.
Shinzato N et al. 2007. Biosci. Biotechnol. Biochem. 71:906-915.
Takahashi SE et al. 2005. Rev. Bras. Cienc. Avic. 7:151-157.
van der Wielen PWJJ et al. 2002. Microbiol. Ecology 44:286-293.
Williams JE. 1978. Disease in poultry. Iowa State University Press.
Zhu XY et al. 2002. Appl. Environ. Microbiol. 68:124-137.
Page 5
Excerpts from the latest USDA National Agricultural Statistics Service
(NASS) “Broiler Hatchery,” “Chicken and Eggs” and “Turkey Hatchery”
Report and Economic Research Service (ERS) “Livestock, Dairy and Poultry
Situation Outlook”
Chicken and Eggs
Turkey Hatchery
Released July 21, 2009 ,, 2009 , by the National Agricultural Statistics Service (NASS)
Released July15, 2009 , NASS, Agricultural Statistics Board, USDA
June Egg Production Down Slightly
Eggs in Incubators on July 1 Down 9 Percent from Last Year
U.S. egg production totaled 7.34 billion during June 2009,
down slightly from last year. Production included 6.29 billion table eggs, and 1.06 billion hatching eggs, of which 988
million were broiler-type and 70 million were egg-type.
Turkey eggs in incubators on July 1, 2009, in the United
States totalled 29.8 million, down 9 percent from July 1,
2008. Eggs in incubators were up 2 percent from the June 1,
2009 total of 29.2 million eggs. Regional changes from the
previous year were: East North Central down 8 percent,
West North Central down 3 percent, North and South Atlantic down 15 percent, and South Central and West down 13
percent.
The total number of layers during June 2009 averaged 333
million, down 2 percent from last year. June egg production
per 100 layers was 2,204 eggs, up 1 percent from June 2008.
Egg-Type Chicks Hatched Up 6 Percent
Poults Hatched During June Down 6 Percent from Last
Year
Egg-type chicks hatched during June 2009 totaled 43.5 million, up 6 percent from June 2008. Eggs in incubators totaled 32.4 million on July 1, 2009, down 3 percent from a
year ago.
Broiler-type chicks hatched during June 2009 totaled 771
million, down 4 percent from June 2008. Eggs in incubators
totaled 631 million on July 1, 2009, down 4 percent from a
year earlier.
Turkey poults hatched during June 2009, in the United
States totaled 24.6 million, down 6 percent from June 2008.
Poults hatched were up 6 percent from May 2009 total of
23.3 million poults. Regional changes from the previous
year were: East North Central down 3 percent, West North
Central up slightly, North and South Atlantic down 12 percent, and South Central and West down 14 percent.
Broiler Hatchery
Released July 29, 2009, by the NASS, Agricultural Statistics Board, USDA
Broiler-Type Eggs Set In 19 Selected States Down 4 Percent
Commercial hatcheries in the 19-State weekly program set
201 million eggs in incubators during the week ending July
25, 2009. This was down 4 percent from the eggs set the
corresponding week a year earlier. Average hatchability for
chicks hatched during the week was 84 percent. Average
hatchability is calculated by dividing chicks hatched during
the week by eggs set three weeks earlier.
Net Poults Placed During June Down 5 Percent from Last Year
The 24.2 million net poults placed during June 2009 in the
United States were down 5 percent from the number placed
during the same month a year earlier. Net placements were
up 5 percent from the May 2009 total of 23.0 million.
Broiler Chicks Placed Down 2 Percent
Broiler growers in the 19-State weekly program placed 167
million chicks for meat production during the week ending
July 25, 2009. Placements were down 2 percent from the
comparable week a year earlier. Cumulative placements
from December 28, 2008 through July 25, 2009 were 5.05
billion, down 5 percent from the same period a year earlier.
Page
Page
6 6
Current Month Charts
Broiler Performance Data
Live Production Cost
Feed Cost/ton w/o color ($)
Feed cost /lb meat (c)
Days to 4.6 lbs
Chick cost / lb (c)
Vac-Med cost/lb (c)
WB & ½ parts condemn. Cost/lb
% mortality
Sq.Ft. @ placement
Lbs/sq. ft.
Downtime (days)
SW
Midwest
Southeast
Mid-Atlantic
S-Central
Company
271.23
24.79
43
4.79
0.04
0.17
4.25
0.80
6.96
15
260.31
23.28
40
4.72
0.02
0.18
4.09
0.80
7.12
12
285.37
25.21
41
5.26
0.08
0.12
3.83
0.83
6.56
17
269.86
25.58
39
4.22
0.05
0.17
4.07
0.98
6.99
17
269.81
24.90
41
4.72
0.04
0.18
3.71
0.82
7.34
15
273.81
24.88
41
4.92
0.05
0.17
3.95
0.84
6.88
Broiler Whole Bird
Condemnation
% Septox
% Airsac
% I.P.
% Leukosis
% Bruises
% Other
% Total
% ½ parts condemns
Average
Region
Region
16
Average
SW
Midwest
Southeast
Mid-Atlantic
S-Central
Company
0.146
0.036
0.008
0.000
0.002
0.005
0.197
0.254
0.206
0.039
0.019
0.000
0.001
0.003
0.269
0.272
0.078
0.035
0.003
0.000
0.003
0.006
0.126
0.186
0.125
0.041
0.010
0.004
0.001
0.012
0.194
0.338
0.095
0.037
0.032
0.002
0.002
0.010
0.178
0.354
0.126
0.036
0.015
0.001
0.002
0.007
0.188
0.300
Data for week ending , 11 July, 2009
Previous Month Charts
Broiler Performance Data
Live Production Cost
Feed Cost/ton w/o color ($)
Feed cost /lb meat (c)
Days to 4.6 lbs
Chick cost / lb (c)
Vac-Med cost/lb (c)
WB & ½ parts condemn. Cost/lb
% mortality
Sq.Ft. @ placement
Lbs/sq. ft.
Downtime (days)
Broiler Whole Bird
% Septox
% Airsac
% I.P.
% Leukosis
% Bruises
% Other
% Total
% ½ parts condemns
Data for week ending, 13 June , 2009
Region
SW
254.51
23.16
42
4.80
0.05
0.17
3.84
0.80
7.07
15
Midwest
243.63
22.20
40
4.69
0.03
0.20
4.28
0.81
7.17
11
Southeast
266.42
23.81
41
5.11
0.09
0.14
3.92
0.82
6.69
18
Mid-Atlantic
258.22
24.37
40
4.39
0.06
0.18
4.00
0.94
7.00
17
S-Central
253.52
23.44
41
4.72
0.03
0.16
3.59
0.82
7.42
17
Region
Average
Company
257.88
230.43
41
4.94
0.06
0.17
3.87
0.84
6.91
16
Average
SW
Midwest
Southeast
Mid-Atlantic
S-Central
Company
0.137
0.042
0.007
0.000
0.002
0.005
0.194
0.261
0.209
0.072
0.030
0.000
0.001
0.003
0.316
0.290
0.072
0.057
0.003
0.000
0.003
0.007
0.143
0.221
0.118
0.071
0.026
0.004
0.002
0.013
0.233
0.309
0.060
0.041
0.024
0.001
0.002
0.006
0.134
0.366
0.119
0.056
0.017
0.001
0.002
0.007
0.202
0.302
Page 7
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Meetings, Seminars and Conventions
2009
August
2010
April
August 23-27: 17th European Symposium on Poultry Nutrition Edinburgh,
Scotland. Online registration preferred
http://www.espn2009.com/generalinformation/
April 20-23: VIV Europe 2010,
Utrecht, The Netherlands. Contact:
XNU Exhibitions Europe B.V, P.O.
Box 8800, 3503 RV Utrecht, The Netherlands, Fax: +31 302-952-809; Website:
www.viv.net
2009
September
September 17-18: The 81st Northeastern Conference on Avian Diseases
(NECAD) will be held in conjunction
with the Pennsylvania Poultry Sales
and Service Conference (PSSC) on at
the Holiday Inn - Grantville, Pennsylvania (Harrisburg Area / I-81 corridor). Titles for scientific presentations
will be due on June 1 and abstracts due
on September 1. Registration materials
and a tentative program will be available
shortly. Titles should be emailed
to : pierson@vt.edu
April 26-30: XII Internatinal Seminar
on Avian Pathology and Production.
Program in Spanish and English.
AMEVEA-University of Georgia, Athens, Georgia. , 2010. Contact: Dr.
Pedro Villegas, Univ. of Georgia.
Seminar2010@uga.edu
2009
November
November 8-12: XVI Congress of the
World Veterinary Poultry Association, Marrakesh/Morocco. Contact:
Prof. Mohomed El Houadfi ,Moroccan
Association of Avian Pathologists
(AMPA), I.A.V. Hassan II, Department de Pathologie Aviaire, BP 6202,
Rabat-Instituts. Phone: +212 (0)7 77 70
53, Fax: +212 (0)7 67 57 15, E-Mail:
mhouadfi@iav.refer.org.ma , For more
information, visit the website: XVI
WVPA Congress, Marrakesh 2009
The University of Georgia is committed to the principle of
affirmative action and shall not discriminate against
otherwise qualified persons on the basis of race, color,
religion, national origin, sex, age, physical or mental
handicap, disability, or veteran's status in its recruit­ment,
admissions, employment, facility and program accessibility,
or services.
Reminder
November 9-11, 2009. AAVMC/
AVMA Joint International Symposium on Animal Welfare Education
and Research to be held, at Michigan
State University. Registration and hotel
reservations now open. For details visit
AVMA web site at http://
www.avma.org/awsymposium/ or
contact, Mike Chaddock mchaddock@aavmc.org or Matt Grogg at
AAVMC mgrogg@aavmc.org .
All previous issues of the
Poultry informed Professional are archived on our
website www.avian.uga.edu
under the Online Documents
and The Poultry Informed
Professional links.
Page 8