European Edition (#2)
Why are researchers investigating the role of
alpha-toxin in the development of necrotic
enteritis? Find out in this issues cover story.
Plus: A Special Report on the
World’s Poultry Congress
Cover Story
'Strong Evidence' Demonstrates Alpha-Toxin's Role in Necrotic EnteritisWhy are researchers
investigating the role
of alpha-toxin in the
development of
necrotic enteritis?
Two scientists share
insights from studies
that could impact
the management of
NE, a serious and
costly disease.
Alpha-toxin Provides Excellent Protection against NE; Other Proteins Likely InvolvedIndependent research by Canadian
investigators using state-of-the-art
technology confirms that alpha-toxin,
a secreted protein from
Clostridium
perfringens, plays a key role in the
development of necrotic enteritis (NE)
in broilers and that other proteins may
also be involved in the pathogenesis
of this complex disease.
NE is a Complicated DiseaseFinding ways to prevent or control necrotic enteritis (NE) in broilers is
challenging because
Clostridium perfringens, the bacterium that causes
the disease, has chameleon-like qualities, and other factors, such as
management, may be involved.
Alpha-toxin Gene Linked to Necrotic Enteritis in IndiaA study conducted on broilers
from India confirmed that
Clostridium
perfringens type A was the cause of
necrotic enteritis (NE) and that alpha-toxin
may play a significant role in development
of the disease, say Arunava Das of the
Bannari Amman Institute of Technology,
and associates.
US Study Suggests Alpha-toxin Plays Role in Cause of NEVaccination of broilers with recombinant
alpha-toxin protected broilers against an
experimental challenge with
Clostridium perfringens,
suggesting that alpha-toxin plays a role in the
pathogenesis of necrotic enteritis (NE).
WPC Forum Special Report
NE vaccine trials in EuropeTwo clinical field trials conducted
in Europe demonstrated that
vaccination of hens with Netvax, a
Clostridium perfringens type A toxoid
vaccine, prevented development of NE
in broiler progeny, reported Dr. Luciano
Gobbi, Intervet/Schering-Plough
Animal Health’s technical manager
for poultry, Italy.
Vaccine lowers NE risk in ‘real-world’ conditionsA trial in the US designed to test the
Clostridium perfringens type A toxoid
vaccine under real-world conditions demonstrated that the vaccine lowers
the risk for NE mortality, according
to Dr. Charlie Broussard, a veterinarian with Intervet/Schering-Plough
Animal Health.
Role of diet in NE questionedDuring a lively interchange between
panel members and the audience, session
chairman Dr. Peter Scott said he has been
surprised at the higher prevalence of NE
in North America compared to Australia,
where the diet for broilers is wheat-based.
Wheat-based diets have been linked to a
higher prevalence of NE.
Alpha-toxin a ‘primary player’In a discussion on the mechanisms of
protection conferred by the
Clostridium
perfringens type A toxoid vaccine,
Broussard confirmed that there is more
to be discovered about why and how the
vaccine triggers immunity.
Toxoid vaccine key to NE controlAsurge of interest in antibiotic-free broiler production
throughout Canada’s poultry industry, coupled with the
eventual availability of an effective vaccine to prevent
necrotic enteritis, could become an important catalyst
for change in the world poultry industry.
Feed additives and NEAcute necrotic enteritis (NE) may come and go like a
storm, but it’s ongoing subclinical NE that does the real
economic damage — and why finding dietary alternatives
to control the disease would be a boon to poultry producers,
said Professor Mingan Choct, chief executive officer
of the Australian Poultry Cooperative Research Center.
Coccidiosis field research yields surprising resultsField research has yielded
unexpected findings about the impact
of clean or used litter on coccidiosis
control and underscores the importance
of initiating coccidiosis immunity early
in broiler flocks.
Management practices that boost performanceAn intensive European study has
pinpointed management factors that can
yield the best performance results in
broilers vaccinated against coccidiosis.
Vaccine is valuable tool in high-end broiler marketParacox-5, an attenuated coccidiosis
vaccine, is playing an important role in
the valuable free-range and organic broiler
markets of South Africa.
Vaccine development — where to from here?Vaccines are emerging as a tool for
managing an increasingly broad range
of poultry diseases even though the
application of new vaccine technology is
slow coming to the poultry industry,
according to two speakers.
Life after antibiotics: Vaccines part of holistic solutionThe poultry industry can produce
birds without the benefit of growth
promoters, but it will take a wellthought-
out holistic approach to make
it work, cautioned Dr. Peter Scott.
Spotlight
Adding More ValueNearly 3 years ago, Dr. Rae Fischer made what some
people in the broiler industry might have called a very brave
decision. Others might have said it was foolhardy.
Fringe benefitsCoccidiosis vaccination used to be viewed solely as a method
for controlling coccidiosis, but years of experience have
transformed it into a broad management tool with multiple
benefits for poultry producers.
Opinion
Science Meets SkillFew would argue that to achieve
the best performance in poultry
or any other species, health care
must be based not just on
sound science but on the skilled
application of science that only
comes with hands-on experience.
Tarjeta Postal
Puerto VallartaVeterinary professionals learned about the
importance of early coccidial cycling during
the 57th Western Poultry Disease Conference
and XXXIII ANECA annual convention held in
Puerto Vallarta, Mexico.
Innovations
Flavored feed has potentialFlavored chicken feed might provide a
way to improve management of broilers
and layers, says B.L. Damron, of the
Institute of Food and Agriculture Sciences,
University of Florida.
Multimedia tool helps producers ensure best broiler diet, growthAn interactive educational program
designed to help broiler operators
ensure optimal coccidiosis control and
maximum growth potential has been
developed by Intervet/Schering-Plough
Animal Health.
Vaccine project targets E. coli, salmonellaThe old adage that “a bird in the hand is
worth two in the bush” may apply to a new
vaccine project underway at Arizona State
University, reports thepoultrysite.com.
Research Watch
NE strains of C. perfringens are mighty gut warriorsStrains of
Clostridium perfringens that
cause necrotic enteritis (NE) replace
C. perfringens strains that do not cause
the disease — and also battle against one
another in the chicken gut — indicates
research that could eventually lead to
improved understanding and better
management of NE.
Performance influenced by diet in coccidiosis-vaccinated broiler breedersIntegrators rearing replacement broiler
breeders should take into account the
finding that early flock performance can
be influenced by dietary composition,
depending on the genetic line and gender,
Leslee A. Oden, of Texas A&M University,
said at the American Association of Avian
Pathologists annual meeting held last July.
Surveys indicate increase in coccidiosis-infected flocksTwo extensive surveys conducted
in Norway indicate the incidence of
coccidia-infected broiler flocks has
increased from 42% to 76% during a
3-year period.