Our virology team plays a vital role in a range of applied research activities
FLOCKVISION
Always eyes in the barn
Your partner in (pre)clinical development
Do you need a contract research organisation to support you throughout the pre-clinical and clinical development of you product? Then partner up with Royal GD!
With our advanced facilities and one of the largest veterinary laboratories in Europe, we are equipped to meet even the most complex research requirements. We excel in controlled environment studies involving poultry, pigs, cattle and small ruminants. We can run multi-country clinical trials in collaboration with our daughter companies throughout Europe, and in compliance with the VICH Good Clinical Practice (GCP) guidelines.
DEAR PARTNERS,
This edition of the GD Update is all about viruses, the diseases they cause and tools to detect them in time. No wonder we invited our Senior Virologist Erhard van der Vries to be on the back page of this edition. In this short interview you can read about our recent discovery of a novel porcine parvovirus.
On page 6 you will find an interview with one of Erhard’s previous colleagues, Prof. Ron Fouchier from Erasmus University. In this article he emphasizes the importance of a well-functioning national monitoring system to stay on top of the spread of highly pathogenic avian influenza. The good news is, we are on top of it but the worldwide spread of the virus in ever more species is worrying. Continuing collaborative research is needed. Just like early and reliable detection, the topic of the next article.
In an extensive interview on page 10 and 11, Dr. Daniel Perez describes his experience with the Alveo Sense Poultry Avian Inflenza test. His research confirmed ‘the kit’s ability to detect low-level positives within pooled samples’.
Challenge models are important tools in developing efficient vaccines against viral diseases. In this edition we describe a few of our newer models, namely a model for PRRSv in swine and a model for Egg Drop Syndrom ’76 in poultry. With our outstanding facilities and broad expertise, GD is the place to go for viral infection studies in poultry and swine!
Finally, on page 13 and 14 we describe a novel tool to continuously monitor the wellbeing of a poultry flock. This application called FlockVision monitors changes in behaviour like eating, drinking, foraging behaviour and resting and demonstrates GD’s continuous drive to innovate and be on the forefront of protecting animals’ health.
Berend Oosterhuis
, Head of Contract Research & Consulting
CONTACT INFORMATION ROYAL GD
If you want to know more about what GD can do for you, please contact one of our staff members, responsible for international sales:
Berend Oosterhuis Head of Contract Research & Consulting b.oosterhuis@gdanimalhealth.com
Annemiek Kolkman Business manager a.kolkman@gdanimalhealth.com
Jarno Smit Business manager j.smit@gdanimalhealth.com
Chantal OnvleeBijlemeer Sales support support@gdanimalhealth.com
Hannelore Braam Sales support support@gdanimalhealth.com
Phone +31 (0)88 20 25 575
E-mail info@gdanimalhealth.com
Website www.gdanimalhealth.com
Mail address GD P.O. Box 9, 7400 AA Deventer, the Netherlands
Editor Update Jessica Fiks
Delivery address for samples and post mortem material
Eveline Peereboom
Business manager e.peereboom@gdanimalhealth.com
Fanny Nieuwenhuis
Business manager f.nieuwenhuis@gdanimalhealth.com
Sebastiaan Bierma Business manager s.bierma@gdanimalhealth.com
Frank Huis in ‘t Veld Sales support support@gdanimalhealth.com
Janine Boertien Sales support support@gdanimalhealth.com
Royal GD, Attn. CMD, Rigastraat 25, 7418 EW Deventer, the Netherlands
04 A robust model to test PRRS vaccines at GD
06 Avian influenza: a One Health problem
09 Avian influenza: advanced point-ofcare diagnostics available
12 New animal model developed for Egg Drop Syndrome ‘76
13 FlockVision: continuous behaviour monitoring
16 GD Specialist: Erhard van der Vries
OUTBREAKS OF PRRS ARE STILL COMMON
A robust model to test PRRS vaccines at GD
The efficacy of vaccines against Porcine Reproductive and Respiratory Syndrome (PRRS) is supported by scientific publications. However, outbreaks of PRRS are still common. GD has now developed a robust PRRSv challenge model to reliably test the efficacy of new vaccine candidates and other innovative control interventions.
PRRS outbreaks result in compromised animal health and welfare and cause economic losses for pig farmers. The continued occurrence of outbreaks worldwide underlines the need for efficacious
vaccines. A thorough method to check vaccine efficacy is therefore essential
What is a challenge model?
A challenge model is an experimental animal study designed to study how infections occur. This model can then be used to assess the efficacy of potential vaccines or other treatments against infections, by deliberately exposing
Lucía Dieste Pérez
“Resolving PRRS in pigs will result in more efficient production, better animal health and welfare”
animals - under controlled conditionsto a pathogen before or after the intervention is administered. GD has developed a challenge model to help determine the efficacy of vaccination –or other interventions - against the PRRS virus. This model can contribute to the development of targeted vaccines for pigs and help reduce economic damages as a result of PRRS. Lucía Dieste Pérez, DVM, MSc, PhD: “With this model, GD is now able to perform efficacy studies for PRRS vaccines. It paves the way for development of effective control solutions.”
Tijs Tobias, DVM MSc PhD, EBVS® European Veterinary Specialist in Porcine Health Management: “Although PRRSv is harmless to humans, better control of PRRSv is a real OneHealth case study. Resolving PRRS in pigs will result in more efficient production, better animal health and welfare, with indirect effects on use of feed, land and antibiotics and resistance induction.”
Challenge Model for PRRSv
A team of researchers from GD has developed the following robust challenge model. This challenge model is suitable for PRRSv-1 (the European genotype). Please find the set-up of the GD PRRSv challenge model in the table below.
What is PRRS?
Porcine Reproductive and Respiratory Syndrome (PRRS) is considered one of the most relevant diseases in pig production worldwide. It is caused by the PRRS virus (PRRSv). Two major PRRSv species are known: PRRSv-1, formerly known as the European genotype, and PRRSv-2, formerly as the North American genotype. Currently, most pig herds in major producing countries are endemically infected with PRRSv. The disease causes reproductive failure in sows, respiratory disease in piglets and deprivation of the immune system. This has a negative impact on swine health with subsequent substantial economic losses. Secondary infections occur often and may require an increased use of antibiotics. PRRSv may spread via direct contact or indirectly via the air or via infected objects. Control of PRRSv is often based on improved management at farm level such as a redesign of stables and hygienic management. Proper monitoring, diagnostics and vaccination are also essential in the control of PRRSv.
PRRSv-1 strain PRRSV-8147
Age of pigs at inoculation7 weeks
Inoculation route Intra-nasal
Model results (post-inoculation) Outcome
PRRSv viremia 100% at 4 days post-inoculation
PRRSv nasal sheddingPeak at 7 days post-inoculation (55% of the pigs)
PRRSv qPCR positive lungs100% at 10 days post-inoculation
Respiratory clinical singsMild respiratory clinical signs (mild dyspnoea sometimes accompanied by coughing or sneezing) and peak of fever at 2 days post-inoculation (average 40.3°C)
GDANIMALHEALTH.COM/STUDIES-PIGS
Tijs Tobias
“In 2024, highly pathogenic avian influenza (HPAI) was detected in –amongst others - cattle and humans in the United States. This also had consequences for human and animal disease monitoring in the Netherlands. The HPAI viruses are difficult to control, but thanks to the strong collaborations built into the Dutch monitoring structure, we are on top of it.”
HPAI, including H5N1, is a monitoring theme that transcends sectors.
Nowadays, bird flu has become wide-
ANIMAL HEALTH
signals like that from monitoring wild mammals, we also have to look into domesticated mammals. If foxes get infected, for example, one needs to keep an eye on cats and dogs as well. And farm animals. In 2024, bird flu was detected in cattle in the USA and the first cases in pigs occurred there as well. Animals kept for their fur were recently seen to suffer from these H5N1 viruses in Europe, but we don’t farm those species in the Netherlands anymore. We are currently keeping an eye on all kinds of mammals because we need to know what is happening.
Screening of cattle
Because of the outbreak in the USA, cattle were also screened in the Netherlands in 2024. Bird flu has not been detected in cattle in Europe yet. In the USA, however, several HPAI viruses
Avian influenza: a
spread in wild birds and is present in Europe all year round. Whereas there used to be only a single peak in the winter months in the Netherlands in some years, since 2020 these viruses have been present continuously. Every spring there is a chance of new incursions via migratory birds from Africa and southern Europe and in autumn by migratory birds from northeastern Europe and Asia. The virus keeps changing, finding other hosts or other locations or new characteristics. This makes HPAI very difficult to control. It is difficult to predict what will happen next and what we need to prepare for this time.
“Avian influenza really is a One Health problem that we work closely on”
Mammals infected
Since 2021/2022, HPAI viruses have been detected in mammals with increasing frequency. Initially, they were seen in wild carnivores such as foxes and martens, also in the Netherlands. And in marine mammals, such as sea lions and elephant seals, which died in large numbers in South America in 2023. When we get
Ron Fouchier
have now been detected. The possibility of facing the same problems in Europe cannot be excluded, but there are major differences between how cattle are kept in the USA and in Europe, and in particular the Netherlands. The numbers of animals per farm are much higher in the USA and animals are moved much more frequently to ‘greener pastures’. The cattle sector is set up differently here; there is less transport and less mixing of populations. This means that the risk of a spreading infection is much smaller. The way we monitor is also better here: we have good systems for that. Production monitoring in the cattle and poultry sectors is sufficient in its own right to reveal issues quickly, before there is even a need for diagnostic testing of animals. Thanks to our monitoring structure, we can identify problems very quickly and tackle them straight away.
“Production monitoring in the cattle and poultry sectors is sufficient in its own right to reveal issues quickly, before there is even a need for diagnostic testing of animals”
One Health problem
Be prepared
We have to take into account that HPAI viruses will not disappear from wild bird populations any time soon and that they can also affect mammals. In the Netherlands, feral cats have already been found to be seropositive for HPAI and in Poland we have even seen domestic cats becoming sick after being fed with infected raw chicken meat. Monitoring of people has been intensified in the Netherlands because of the zoonotic risks. When there is an outbreak at a poultry farm, for example, animal caretakers, veterinarians and persons involved in culling are monitored for possible infections.
Pigs
Pigs are well-known as hosts for influenza viruses, unlike cattle in which these viruses were seen for the first time only last year. There has been a pilot study for monitoring swine flu in the Netherlands for several years now, to get some insights into the circulating viruses. This is a collaboration between GD, the National Institute for Public Health and the Environment (RIVM), Wageningen Bioveterinary Research (WBVR) and
Erasmus MC, commissioned by the ministries of Health, Welfare and Sport (VWS) and Agriculture, Fisheries, Food Security and Nature (LVVN). Veterinary practices are also closely involved. The ministries have asked to include avian influenza in this surveillance. We indeed include bird flu, but coverage is not 100% for pigs unlike in poultry farms in the Netherlands. All farms are monitored in the poultry sector, whereas for pig farms this is just a small selection, spread throughout the Netherlands.
More intense collaborations
It is becoming increasingly clear that HPAI is not a task for a single branch or sector. It is a genuine One Health problem. This can also be seen from the fact that the parties concerned –such as GD, RIVM, WBVR, Utrecht University (UU) and Erasmus MC – are increasingly working together because the risks for
“Several joint research programmes are currently being rolled out by the parties involved in the monitoring”
humans and animals are closely linked. We see collaborations in various monitoring and research programmes, ranging from monitoring wild birds and mammals to studies on humans. These collaborations are running increasingly smoothly. There are excellent contacts between the groups now and everyone has come out of their own little bubble to tackle this problem together.
Strong One Health
Several joint research programmes are currently being rolled out by the parties involved in the monitoring. The Strong One Health (Strong1H) programme commenced last year, for example. Europe has made money available to help locate and bridge any gaps between the major regular monitoring programmes. The research is looking at avian and swine influenza and the West Nile virus in various animal species.
Strong1H is a consortium consisting of WBVR, GD, the Erasmus MC, UU/Dutch Wildlife Health Centre (UU/DWHC) and the RIVM.
AVIAN INFLUENZA IN POULTRY
Advanced point-of-care diagnostics available
When it comes to poultry production, the threat of avian influenza means we need to improve our diagnostic technologies so we can detect and respond to the disease quickly. Because, how do you get a grip on bird flu? And how can you use the available diagnostics and improve management to prevent outbreaks and reduce the potential threat of zoonosis?
Alveo Technologies, Inc. and Royal GD decided to join forces and developed an on-site poultry avian influenza test: Alveo Sense™. This test gives you accurate, laboratory-grade results whenever you need them, using a cloud-connected, data-driven platform.
This technology is currently being used across the European Union, the Middle East, and Southeast Asia and parts of Africa. The Poultry Diagnostics Research Center (PDRC) conducted a two part study to see how well the Alveo Sense™ test could spot high and low pathogenic H5N1 viruses in chickens and ducks. In the first phase, ducks were monitored over five days with daily collection of oropharyngeal and cloacal swabs. The samples were analysed to determine viral load and evaluate the
sensitivity of the test. The second phase was all about testing out the effects on chickens and ducks, and that took six days.
The PDRC study has shown how well the Alveo Sense™ test can detect the H5N1 virus in chickens and ducks during the early stages of infection. PDRC is a renowned global player in the College of Veterinary Medicine at the University of Georgia. It’s about giving poultry producers the support they need, whether it’s through teaching, research, helping out with diagnostics, or offering expert advice.
Highresented accuracy and sensitivity
Initial testing revealed an impressive >99% accuracy in detecting Type A and H5 targets across all tests, including from pooled cloacal swabs in ducks, which are considered the most complex sample type. The early time-to-result values underscored the platform’s strong analytical sensitivity, confirming its suitability for detecting viruses even at low levels. The findings support the utility of the Alveo Sense™ test for field-based surveillance efforts, enabling the feasibility of sample pooling strategies.
Dr. Daniel Perez from PDRC presented the study findings at the 15th International Seminar on Poultry Pathology and Production.
What are the results or relevant findings?
“In the first study, we used Alveo’s kit to monitor HPAIV in cloacal (CL) swabs from ducks challenged with 10^4 TCID50 of an H5N1 strain. Daily sampling over five days demonstrated that even when only one duck was positive, the kit generated a detectable signal. This sensitivity highlights the potential of the platform for early detection in real-world settings. The study was concluded on day 5 when the ducks reached humane endpoints, but the data clearly demonstrated the kit’s ability to detect low-level positives within pooled samples.
In the second study, we challenged both ducks and chickens with either 10^6 or 10^4 TCID of a low-pathogenic H5N1 strain, with cloacal (CL) and oropharyngeal (OP) samples collected from 5 birds daily, across six days. OP pools from chickens consistently produced type A and H5 signals on days 1, 3, and 5, in line with expected virus shedding dynamics.
“Daily sampling over five days demonstrated that even when only one duck was positive, the kit generated a detectable signal”
Notably, on day 5, the Alveo Sense kit provided a positive signal even when virus levels were below the limit of detection, underscoring the system’s sensitivity. While chicken CL swabs returned inconsistent results, this is likely attributable to sample type or workflow deviation rather than test performance. In ducks, OP samples reliably detected type A and H5 signals on days 2 and 4, and CL samples yielded positives on day 4, demonstrating strong agreement with viral dynamics.”
Can you elaborate on the specific challenges that you encountered while testing the Alveo Sense™ Poultry Avian Influenza test, and how these were addressed?
“Testing in LPAIV-H5N1 challenged ducks showed results consistent with viral load measurements, and even partial detections provided actionable information. At 2 DPI, OP swabs were positive for H5 and CL swabs were positive for Type A, demonstrating that the test could reliably flag samples that would warrant confirmatory testing in the field.
In LPAIV-H5N1 challenged chickens, OP pools performed as expected, confirming that the test could track infection dynamics in this specie, while CL pools produced some irregular
Daniel Perez, PhD
Georgia Research Alliance Distinguished Investigator and Caswell S. Eidson Chair in Poultry Medicine within the PRDC “Properly evaluating poultry for avian flu is critical, requiring enhanced bio-surveillance and biosecurity tools. These studies demonstrated that molecular testing with Alveo Sense poultry avian influenza test produces highly sensitive results at clinically relevant virus shedding levels. These findings support the test’s performance in the field to enable rapid decision-making, timely action and better outcomes. Now more than ever, this type of solution is essential as the bird flu catastrophe continues to worsen,”
results. The negative result at 3 DPI likely reflected a low viral titer, and the invalid result at 1 DPI may have resulted from a minor workflow deviation. Confirmatory RT-PCR is underway on the 5 DPI OP pool to validate these findings.”
Can you describe your trial with cloaca testing?
“For the first phase of the study, five mallard ducks (2 weeks old) were experimentally infected with a prototypic strain of clade 2.3.4.4b H5N1 HPAIV at a dose of 1×104 TCID50/duck (500 μL via oculo-nasal-tracheal-cloacal routes). Clinical signs were monitored for five days. Daily, oropharyngeal and cloacal swabs were collected from each duck. These samples were then analyzed to
determine viral load (log10 TCID50/mL) and to assess the sensitivity of the Alveo Sense Poultry Avian Influenza Test Type A H5 H9.
PDRC determined viral titers by infecting Mammalian MadinDarby Canine Kidney (MDCK) cells with serial dilutions of each individual swab1. TCID50 values were calculated using the Reed and Muench method and expressed as log10 TCID50/mL. PDRC followed the intended user workflow of the Alveo Sense test in running the cartridges. The Alveo Sense test was run three times during the study, using pooled cloacal swabs from all five birds on days 1, 3, and 5 post-infection. Results via the mobile application were reported qualitatively, in line with the current design of the Alveo Sense platform. The raw data from all three runs were also extracted and analyzed for further evaluation.”
Are there any comparable diagnostic tools currently available on the market? If so, how does the Alveo Sense™ test compare to these existing methods in terms of sensitivity, specificity, and ease of use?
“While I’m not familiar with the full spectrum of available tests, our limited comparison of the Alveo Sense kit and a standard commercial antigen capture test showed a clear performance advantage for the Alveo Sense test. This is primarily because this test uses nucleic acid amplification, a more sensitive method than the antigen-capture test’s reliance on viral antigen concentration. Crucially, I see both types of assays as valuable and complementary tools for outbreak management, allowing for diverse strategies to facilitate rapid intervention and effectively curtail influenza spread.”
You recently presented at the FAO meeting. How did that opportunity arise, what was presented and what was the feedback?
“Following the initial presentation at UGA in August, I’ve continued to share findings from our initial stages of the evaluation of Alveo Sense at congresses in Pennsylvania and recently the FAO meeting in Brazil. It is my belief that tools like the
Alveo Sense is an on-site molecular test for notifiable Avian Influenza (H5 and H7 subtypes) as well as the major global endemic strain affecting commercial poultry production (H9 subtype). It’s a patented method of direct electrical sensing of nucleic acid amplification, and the test differentiates between H5, H7 and H9 subtypes. The kit is self-contained and has everything you need to do the test, so you can use it on farms and out in the field. You’ll get the results on your phone in about 45 minutes, so you don’t need to go to a central lab. The Alveo Vista™ portal automatically adds location tags to the raw data and analytics, uploads them to a secure cloud environment, and exports them for regulatory agencies and state veterinarians to make use of.
Alveo Sense point of need test have the potential to improve when and how we respond to outbreaks. Ultimately allowing for stronger biosecurity efforts to minimize the impact both on site and at surrounding facilities. The information was well received in Brazil with those in attendance understanding the value of a tool like this.”
What implications do your study findings have for the future of avian influenza surveillance and control strategies on a global scale?
“The FAO meeting ended with attendees collaborating to establish a list of six recommendations for government entities to use to battle avian influenza. That included an emphasis on the
“Preventing and controlling avian influenza in poultry requires reliable surveillance systems capable of promptly tracking vaccine breakthroughs in the field”
use of data technology. There is a strong need to utilize data technology for diagnostic advancements or centralized real-time data management. A capability that this test can support via real-time Geotagging.
Further, these studies demonstrated that molecular testing with Alveo Sense Poultry Avian Influenza test produces highly sensitive results at virus shedding levels that are clinically relevant. These findings support the performance of the test in the field to enable rapid decision making, timely action and better outcomes. Now more than ever, this type of solution is essential as the bird flu catastrophe continues to worsen.”
Is there anything else you’d like to share about this project or anything else that PDRC is currently working on to combat Avian Influenza?
“Integrating the Alveo Sense test into our avian influenza research at the PDRC – including studies on interspecies transmission, pathogenesis, and vaccine development – is a significant step forward. The assay’s excellent sensitivity and specificity are critical for accurately assessing protection against virus shedding in our vaccination and challenge studies. Ultimately, preventing and controlling avian influenza in poultry requires reliable surveillance systems capable of promptly tracking vaccine breakthroughs in the field. I am confident that Alveo’s technology will be an invaluable component of this necessary surveillance infrastructure.”
Hanneke Bataille, researcher
OCCURRENCE OF THE EDS VIRUS IS WIDESPREAD
New animal model developed for Egg Drop Syndrome ‘76
Recently a new animal model was developed at GD for Egg Drop Syndrome ’76 (EDS), a viral disease that primarily affects laying hens, leading to decreased egg production, poor egg quality, and abnormalities in the eggshells such as thin or soft shells.
The disease can result in significant economic losses for the poultry industry, due to the reduced number and quality of eggs produced. Infected birds typically show no clinical signs, therefore the diagnosis is based on egg production and egg quality problems. Control measures include vaccination, biosecurity, and management strategies to prevent the introduction and spread of the virus within and between flocks. Occurrence of the EDS virus is widespread in domesticated but also in wild ducks and geese. Nevertheless, outbreaks in commercial poultry are rare, due to routine vaccination in most parts of the world. EDS is often one of the components in a multivalent inactivated vaccine.
Focus on egg production
The efficacy of the EDS component in an inactivated vaccine can now be assessed using the EDS challenge model that is available at GD. The challenge model focuses on egg production after a challenge with EDS strain BC14 by eye-nose drop at 30 weeks of age. Egg production is measured from onset of lay until four weeks after challenge to evaluate if vaccination protects the birds against a drop in egg production and/or egg quality. Groups of 30 chickens (3 replicates of 10) are used to be able to detect significant differences between groups. The birds can be housed in floor pens or isolators. On average the non-vaccinated control birds show a marked drop in egg production of 15% after EDS challenge. No clinical signs or mortality are induced, and few abnormalities are found in the reproductive tract at postmortem examination.
ALWAYS EYES IN THE BARN
FlockVision: continuous behaviour monitoring
GD has introduced a new product: FlockVision. It is a tool to measure the behaviour of broiler chickens. FlockVision helps you to identify changes in behaviour. Six behaviours are measured using camera images: drinking, eating, foraging behaviour, comfort behaviour, walking and resting. This provides a better insight into animal health and welfare.
Willem Dekkers, GD researcher and poultry veterinarian: “You
chickens do when you’re not around. In addition, not everyone is equally trained in assessing poultry behaviour. If you want to be able to comment on the health and welfare of broilers, you need to observe them. With FlockVision their behaviour is scored continuous and the result is a dynamic ethogram. Using a camera to analyse behaviour offers many advantages. It’s objective and independent of people, you can assess more animals simultaneously, making the process much less labour-intensive.”
Testing and developing
FlockVision was developed by GD experts over the last couple of years. Willem: “We tested the system in the Netherlands. Four broiler farmers took part during the pilot. They installed a surveillance camera in the barn. Based on this footage, individual broilers were identified and on these individual chickens, an Artificial Intelligence model was trained to score it’s our. It is good to know that FlockVision retrieves and analyses the camera images locally and sends only the observed behaviour to the app. This means that, except for the farmer, no one else can see the camera footage. Only the scores that the system assigns are sent to the cloud. This allows us to create a benchmark and warning system within the app in the future.”
Six key behaviours
FlockVision provides continuous monitoring of sixteen behaviours, categorised into six behaviour groups: drinking, eating, foraging behaviour, comfort behaviour, walking and
Jessica Fiks, editor
Willem Dekkers
resting. The clear dashboard on your app provides real-time insight into changes in your flock’s behaviour. This enables you to take immediate action in the event of any unexpected changes in the behaviour of your broiler chickens.
• Drinking: Picking to a drinking nipple or drinking out of the cup.
• Eating: Eating with head above or in the feeder.
• Foraging behaviour: Activities such as floor scratching, where the animal scrapes through the bedding with its claws, and ground pecking, where the animal makes pecking movements in the bedding.
• Comfort behaviour: Activities such as preening, where the bird uses its beak to clean its own plumage to keep the feathers clean and in good condition, and stretching, where the bird stretches its wing or leg.
• Walking: The bird moves around.
• Resting: Standing still. The animal remains stationary without any other activity, and sitting, where the animal lies down or sits without any other significant activity.
Get to know Flockvision
Willem: “We launched the product in the Netherlands in may 2025 and next to the pilot farms we are now connecting the first customers. FlockVision gives them insight into what their broilers are doing. How many broilers are eating, drinking and resting? How many percentage is performing comfort behaviour? Is there something strange happening? Do we see differences between poultry houses? Because we are still developing the product, you can try FlockVision at a reduced prize. The time is right to offer FlockVision to our international customers as well.”
IF YOU ARE INTERESTED IN FLOCKVISION TAKE A LOOK AT OUR WEBSITE
Gerhard de Ruiter Managing Director GD
Royal GD in Deventer welcomes Gerhard de Ruiter as its new Managing Director. He succeeds Ynte Schukken, who will fully dedicate himself to his role as CEO of the GD Group. Gerhard will join GD on 1 November 2025. As of 1 December, he will fully assume the responsibilities of Ynte Schukken.
Gerhard brings extensive knowledge of the agrifood sector and broad experience in leadership within both commercial and academic environments, in innovation, and in translating science into practical, impactful solutions. Gerhard: “I look forward to working with Royal GD’s dedicated team to further build a future-proof organization that has been supporting farmers, veterinarians and veterinary businesses for more than a century. Together, we will strengthen our position as the leading partner in animal health and contribute to a healthy planet and a healthy society.”
VIV MEA 2025
From November 25 to 27, Royal GD will be present with a booth at VIV MEA 2025 in Abu Dhabi. We look forward to meeting interested parties to demonstrate our new Alveo Sense test for highly pathogenic influenza and explain the benefits of using this test. Additionally, we are available to answer all your questions regarding diagnostics and contract research for multiple animal species.
Have you heard about our new AI tool, Flockvision? You can find out more about it in this GD Update, and we look forward to telling you more about it in person at the ADNEC Centre.
Replay webinars
Expert session: Enterococcus cecorum infections
Dr Thijs Manders presented his research on Enterococcus cecorum infections. Dr Manders has specialised in bacterial diseases in poultry since 2018. Key topics of the webinar:
• Virulence of E. cecorum strains
• Pathogenesis of E. cecorum infections
• In vitro and in vivo models to study E. cecorum
Avian influenza and molecular diagnostics
Watch the replay of the expert session on avian influenza, presented by Sjaak de Wit. In this webinar, he discusses
how molecular diagnostics for avian influenza have evolved and emphasises the importance of early detection and rapid containment in minimising the impact on poultry production.
Streptococcus suis animal model
In this webinar, Erik van Engelen discussed the causes and impact of Streptococcus suis infection, and demonstrated how our animal model can be used to understand how the infection progresses and to evaluate preventive and curative measures.
Free microplate test standard HPAI antigens
Our newly developed H5N1 and H5N8 antigens are the most up-to-date inactivated antigens for these strains and are specifically designed for use in the Haemagglutination Inhibition (HI) test to ensure accurate detection of antibodies in poultry. These antigens are essential tools for accurate monitoring and rapid response to potential outbreaks, ensuring the health and safety of both poultry and humans.
With the newly developed microplate test standard, you can standardise the HI test and read the microplate at an angle of 45 degrees. This makes it easier to read the test, especially the so-called tear formation. Order the new H5N1 and H5N8 antigens now and receive a free microplate test standard.
CRI Grant awarded to Lonneke Vervelde
Our researcher, Lonneke Vervelde, has been awarded a prestigious grant from the 2025 Cobb Research Initiative (CRI). The CRI promotes poultry genetics by fostering cross-disciplinary collaboration, which is crucial for addressing challenges such as disease prevention, animal welfare, production efficiency, and product quality.
Her innovative project, ‘Intestinal Organoids as a Phenotyping Tool to Screen Genetic Lines for Microbial Resilience’, will advance poultry genetics research and contribute to improved disease prevention and animal welfare.
WATCH OUR WEBINARS
GD R&D Specialist: Erhard van der Vries
Erhard van der Vries is a molecular biologist who earned his PhD in virology in 2014. Since then, he has held various national and international research positions focused on studying zoonotic virus infections in humans and animals. In 2019, he was appointed as a senior scientist in the Research & Development department at Royal GD.
“Our virology team plays a vital role in a range of applied research activities within the company,” says Erhard.” For instance, we prepare viruses for vaccination-challenge studies for our contract research clients and purify virus antigens for diagnostic assays. In our virology lab, we employ diverse laboratory techniques, ranging from classical virus cultures in embryonated chicken eggs and cell culture systems to cutting-edge virus sequencing and detection methods used to identify novel virus pathogens.”
New Porcine Parvovirus
Using such research tools and with great interdisciplinary team effort, we recently discovered a novel porcine parvovirus in young piglets with ocular abnormalities. “Within the virology team, we managed to isolate this virus in a porcine cell line and identified the cells infected by this virus in the affected animals,” explains Erhard.
Influenza Surveillance in Swine
Erhard has a long scientific track record in influenza research, with a specific interest in the topic of zoonoses. “Arguably, the influenza virus is among the viruses with the highest zoonotic potential,” Erhard notes. Recently, GD set up an influenza surveillance programme in swine to investigate the circulation of swine influenza viruses in pig farms in the Netherlands. This was done in close collaboration with a network of partners from various national veterinary and public health institutes. “One of the early research findings of this programme was the observation that the epidemiology of swine and human influenza viruses are interconnected. We observed sporadic zoonotic cases of swine influenza viruses in human patients, and vice versa; human influenza viruses were detected in the swine population,” he adds.
“As a R&D virologist, I really enjoy the working environment at GD, surrounded by a team of passionate scientists, veterinarians, skilled laboratory personnel, and supportive staff,” says Erhard.
