Merck Animal Health Presents New Data Highlighting Commitment to the Health and Well-Being of Swine, As Well As Pig Farm Management at ESPHM 2023

Multiple studies demonstrate the benefit of needle-free vaccination for the prevention and management of Lawsonia intracellularis

Additional novel research includes reproductive health, preventive farm care and herd health management

MADISON, N.J., May 24, 2023 – Merck Animal Health, known as MSD Animal Health outside of the United States and Canada, a division of Merck & Co., Inc., Rahway, N.J., USA (NYSE:MRK), today announced the presentation of 19 abstracts at the 14th European Symposium of Porcine Health Management (ESPHM), highlighting new research across the company’s broad swine portfolio, including its intradermal vaccine PORCILIS® Lawsonia ID. ESPHM 2023 will be held in Thessaloniki, Greece, from May 31 to June 2, 2023.

The Company will also present data on a new rapid blood progesterone kit by comparing it to a laboratory-based progesterone assay and to the reproductive status of the gilt as measured by postmortem examination of the reproductive tract at an oral presentation on the “Flash Talks” session from the Symposium, which would take place on Thursday, June 1st at 15h.

“As a company dedicated to the health and well-being of swine and the sustainability of pig farms, Merck Animal Health is pleased to share data across our innovative portfolio of vaccines, health management solutions and value-added services,” said Rika Jolie, DVM, Ph.D., MBA, Head of Global Swine, Merck Animal Health. “This new research emphasizes our commitment to the Science for Healthier Animals and demonstrates how the Company’s latest scientific advances, products, and services can benefit both the swine and the farmer.”

Key data to be presented at ESPHM 2023 include:

Intradermal vaccination against Lawsonia intracellularis at the beginning of fattening reduces animal losses and improves feed efficiency

Lawsonia intracellularis is a common pathogen in swine farms around the world, causing diarrhea and poor growth that results in economic losses. While the acute form occurs most often in pigs between four and 12 months, chronic forms can be present from six weeks onwards. Immunity after intradermal vaccination with PORCILIS Lawsonia ID can be expected in four weeks.

This study evaluated three fattening farms in Germany with a history of acute and chronic ileitis during fattening to determine whether vaccination at the beginning of the fattening period can still achieve a benefit. Comparing historical performance data of non-vaccinated pigs (n=1,711) with vaccinated pigs (n=1,658 pigs), the study found that feed conversion ratio improved in all farms and contributed to a reduction in production costs, ranging from 0.80 to 6.60 Euro/pig. In addition, animal losses and antibiotic treatment was reduced in two of three farms. Observations from these case series show that vaccination at the beginning of fattening can be a sufficient measure to control ileitis during fattening and to improve feed efficiency on the farm.

  • Abstract HHM-PP-55 Using a novel needle-free intradermal vaccine against Lawsonia intracellularis at the beginning of fattening: practical observations on performance in three fattening farms

Intradermal vaccination also decreases bacterial load in feces and associated symptoms

Lawsonia intracellularis in feces is negatively correlated to average daily weight gain. Intradermal vaccination with Porcilis Lawsonia ID has been shown to be effective in decreasing bacterial shedding and improving daily weight gain.[i] This study evaluated bacterial load before and after vaccination in nursery pigs among seven sow farms (n=70–1,750 sows/farm).

The average number of Lawsonia intracellularis bacteria in quantitative polymerase chain reaction (qPCR) showed a difference of 1.72(log10) or approximately a reduction between 104-105/mL, before and after vaccination. The results demonstrate that the number of bacteria in feces correlates to severity of disease, and intradermal vaccination can reduce bacterial load and consequently symptoms in growing pigs.

  • Abstract IMM-PP-06: Intradermal vaccination against Lawsonia intracellularis decreases bacterial load in feces

Next-gen sequencing enables characterization of changes in intestinal viruses associated with wasting disease in piglets

Previous studies have shown specific changes in the enteric virome (collection of intestinal viruses) before and after weaning between healthy piglets and piglets at risk for wasting disease.[ii] In this study, a farm without clinical signs of wasting disease was monitored to characterize the healthy virome composition of piglets. Next generation sequencing (NGS) was used to characterize the enteric virome composition, combined with specific qPCRs for Rotavirus (RV) A and C, and Porcine Astrovirus (pAstV) 1-5.

In healthy piglets, low viral levels present prior to weaning increased sharply one week after weaning and diminished three weeks post-weaning. In contrast, the enteric virome of piglets at risk for wasting disease included a high viral load before and after weaning. This study characterized the apparent enteric virome of healthy piglets, confirming that NGS enables characterization of virome changes associated with wasting disease.

  • Abstract VVD-PP-16: Changes in the enteric virome around weaning in a healthy pig farm

Rapid blood progesterone kit accurately evaluates progesterone (P4) levels, to assess status of gilt reproductive tracts for the control of reproductive problems

Progesterone (P4) levels can verify the accuracy of heat detection and the estrous status of a population as well as ensure appropriate hormone intervention. This study evaluated a new rapid blood progesterone kit (Biovet Progesterone Kit) by comparing it to a laboratory-based progesterone assay and to the reproductive status of the gilt as measured by postmortem examination of the reproductive tract. A blood sample was obtained from 57 gilts at different stages of their reproductive cycle, and the reproductive tracts were examined after slaughter.

The data revealed a strong correlation between the status of gilt reproductive tracts and both the Biovet Progesterone Kit and lab tests to assess P4 levels, indicating that either of the two P4 tests to determine cycle status of individual gilts or sows can be used, without the need to send gilts or sows to slaughter.

  • Abstract FTP-OP-09: Correlation between the assessment of the reproductive system in gilts and the levels of Progesterone (P4), for the control of reproductive problems

Merck Animal Health scientific publications will be available on after the congress. Please visit booth #2 for more information.

About Merck Animal Health

At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than a century, we’ve been at the forefront of research, bringing forward medicines, vaccines and innovative health solutions for the world’s most challenging diseases. Merck Animal Health, a division of Merck & Co., Inc., Rahway, N.J., USA, is the global animal health business of Merck. Through its commitment to The Science of Healthier Animals®, Merck Animal Health offers veterinarians, farmers, pet owners and governments one of the widest ranges of veterinary pharmaceuticals, vaccines and health management solutions and services as well as an extensive suite of connected technology that includes identification, traceability and monitoring products. Merck Animal Health is dedicated to preserving and improving the health, well-being and performance of animals and the people who care for them. It invests extensively in dynamic and comprehensive R&D resources and a modern, global supply chain. Merck Animal Health is present in more than 50 countries, while its products are available in some 150 markets. For more information, visit and connect with us on LinkedInFacebookTwitter and Instagram.

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[i] Prescribing Information for Porcilis® Lawsonia ID at

[ii] Folgueiras-González, A.; van den Braak, R.; Deijs, M.; Kuller, W.; Sietsma, S.; Thuring, V.; van der Hoek, L.; de Groof, A. Dynamics of the Enteric Virome in a Swine Herd Affected by Non-PCV2/PRRSV Postweaning Wasting Syndrome. Viruses 2021, 13, 2538, doi:10.3390/v13122538.