Page 13 - National Poultry Newspaper

Photo: Drew Hays
E. coli vaccination is safe for hens in lay
The EDUR pump ef- fectively replaces the standard pump, the air compressor and the air saturation vessel.
A NEW study from Denmark shows that a live vaccine against escherichia coli can safely be used in hens in lay, a practice that may help limit e. coli trans- mission in both broiler and egg production.
be all over, especially in the litter,” Dr Christensen said.
has fallen out of favour in Denmark and elsewhere due to concerns about an- tibiotic resistance.
parents in Denmark. Investigators sought to determine firstly the effect of vaccination on layer health, laying per- formance and hatching results, and secondly whether the vaccine strain could shed cloacal- ly and survive in and on
In addition, he said, the vaccine had no adverse effects on health and production parameters – number of eggs, hatching and progeny – when ad- ministered to birds in lay.
The EDUR mul- tiphase pump has a unique design, ena- bling it to handle an air and water combi- nation.
This system simplifi- cation also has an im- pact on running costs.
According to the study’s author and a professor at the University of Copen- hagen Henrik Christens- en, e. coli can be trans- ferred horizontally and vertically in poultry pro- duction and both cause serious problems.
“If the hen is infected, then her eggs can also be infected by e. coli, and this infection will be transferred into the hatcher and into the day- old broilers.
A third option is vac- cination, which he said is commonly used in layers and broiler breeders dur- ing rearing.
“Based on these results, we can say that it’s pos- sible to use a vaccine with hens in lay without any adverse effects,” Dr Christensen said.
EDUR Pumps of Kiel in Germany has been building applica- tion specific pumps since 1927.
“Horizontal transfer oc- curs in the hatcher but it will also occur in the poultry house during pro- duction, where e. coli will
Traditionally, he ex- plained, treating the day- old chicks with antibiot- ics has controlled vertical transmission.
“When the hens start laying, they are more stressed and additional stress caused by vacci- nation could cause more harm,” Dr Christensen said.
were in lay at 30 weeks. Egg samples and cloacal swabs were taken three and seven days follow- ing the third vaccination to determine presence of the e. coli vaccine strain inside and on the surface
“So that can be two rea- sons to vaccinate hens in lay both for broiler parents and for table egg layers.
As with the con- ventional system, the EDUR pump ‘forces’ the air into solution
Australian food pro- ducers can now take advantage of these technologically ad- vanced and cost saving processes.
Live poultry linked
to salmonella
outbreaks in US
“So people have been reluctant to vaccinate.”
of the eggs.
Results indicated that
THE US Centres for Disease Control and Prevention have linked live poultry and backyard birds to salmonella cases in 28 states.
and purchase new chicks.
The study, recently published in Veterinary Microbiology, was con- ducted by the University of Copenhagen in a flock of more than 10,000 layer
“From the samples we took, we isolated e. coli bacteria and we then used various methods to iden- tify the vaccine strain,” Dr Christensen said.
“It’s also a way to lim- it the spread of e. coli, some of which have a zoonotic potential to be transferred into the hu- man food chain.”
Live poultry in back- yard flocks across the country have caused salmonella infections that have sickened 97 people.
However, the CDC warns that people can get salmonella from lax biosecurity proto- cols or touching live poultry.
“We were not able to recover the vaccine strain three days after vaccina- tion in and on the eggs, or from the cloacal swabs.”
Reporting in Medi- calXpress indicates that 17 people have been hospitalised.
The CDC recom- mends all backyard flock owners wash their hands thoroughly with soap and water after touching live poultry and anything in their environment.
No deaths have been reported in this out- break.
Owners should be ad- vised not to kiss back- yard poultry, nor let children younger than five touch the birds because children are more likely to contract severe salmonella in- fections.
Nearly a third of the confirmed cases are children under five
Spring and summer are popular times to build backyard flocks
www.poultrynews.com.au
National Poultry Newspaper, June 2020 – Page 13
Photo: Karim Ghantous
“So it’s difficult to con- trol horizontal transfer — it’s easier to control the vertical transfer.
Another option is to improve management, he added, but that can only work to a certain extent.
It is set up with a restrictor valve on the suction and an air ‘snorkel’, which draws in atmospheric air in- to the suction of the pump.
No compressor to run and maintain, and no maintenance or yearly recertification on an air saturation vessel.
“So we have to focus on vertical transfer for control.”
However, he noted, vac- cination has not tradition- ally been used in hens in lay due to a lack of safety data.
the surface of the eggs. The birds were given a live e. coli vaccine twice during rearing at five days and 14 weeks, and a third time while the birds
“The vaccine strain will not survive in the produc- tion environment or on the eggs.
The pump then sheers and mixes the air with the water be- fore discharging it un- der pressure to mimic what would happen in the conventional sys- tem – within the pres- sure vessel.
Though relatively new to the Australian market, they have been successfully supplying DAF pumps to Euro- pean, Chinese and US food manufacturers for over 20 years.
However, this approach
“One reason is of course to protect the hens them- selves — so we have a lower mortality related to e. coli and also more ani- malwelfare.
Another concern was the possibility of live vaccine strains surviving in the environment and recombining with field strains, putting both bird health and food safety at risk.
the vaccine strain was not shed cloacally and was not present in and on the eggs.
“The other reason is mainly related to broiler parents because by lim- iting the level of e. coli infection, we’re able to limit the vertical transfer of e. coli to the broilers.
Simple and easy DAF system
DISSOLVED air flo- tation systems can be complicated, with pump, compressor, air saturation pres- sure vessel and con- trols, but this compli- cation can turn into ‘set and forget’ by using an EDUR ‘mul- tiphase’ pump.
with back-pressure created by a discharge restrictor valve.
According to Aus- tralian distributors, Hydro Innovations, the EDUR DAF pump does not need com- pressed air and does not need an air satura- tion vessel.
When the air satu- rated water is released back into the DAF tank, the air comes back out of solution forming micro bub- bles 30-50 micron, and floats fats, oil and grease to the surface for collection.