Science Page: High levels of dietary zinc under a cloud

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

The addition of zinc in pig’s diet had been a common way to fight against enteric issues at weaning without using antimicrobial in some European countries whereas its use was prohibited in others. Earlier this month, the European Union decided to homogenize practices over the continent by banning the use of high levels of zinc in the diet over environmental and antimicrobial resistance concerns. This new legislation will be implemented progressively over 5 years.

Key points from this week edition:

  • High level (2,500 – 3,000ppm) zinc use (HZU) in feed for 1 to 2 weeks post weaning to counter enteric disease is perhaps the most widely adopted alternative to antibiotic use in pig production globally.
  • The European Union just announced a ban on HZU in piglet feed, to be phased in over 5 years
  • Banning of an effective and widely adopted alternative to antibiotics, at least in part due to perceived concerns about coselection of resistant bacteria, adds another layer of complexity to the development and validation of all interventions to replace antibiotics in food animal production.

Read Dr. Peter Davies’ explanation of the reasons behind this ban.

Science Page: Continued reporting on unusual CNS cases

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week, the Science Page focuses on unusual Central Nervous system (CNS) cases that have been emerging in the past few years. Etiological agents like porcine teschovirus (PTV), porcine enteroviruses (PEV), porcine sapelovirus (PSV), and atypical porcine pestivirus (APPV) have been implicated in those cases leading to the creation of a set of criteria to positively identify a CNS case.

Three criteria are therefore required: identifying the clinical signs, a positive PCR test for one or more of the viruses, and histological results consistent with viral encephalitis from spinal cord or brain tissue.

Key points from this week edition:

  • An apparent increase in the number of cases associate with atypical neurological signs have been observed over the last two years.
  • Since then, the Veterinary Diagnostic Laboratories (VDLs) have identified a set of criteria required to meet the CNS case definition.
  • MSHMP will continue reporting CNS cases diagnosed at the KSU, ISU, SDSU, and UMN VDLs.

Take a look at the number of cases recorded since September 2016.

Eliana Silva Paladino and Jose Angulo to receive Pijoan and Leman swine fellowships.

The recipients of the Pijoan and Leman fellowships were revealed last week and we are proud to announce that two great candidates were selected.

paladino_elianaDr. Eliana Silva Paladino is receiving the Carlos Pijoan fellowship. Eliana obtained her DVM and MS degrees in Brazil and is currently a PhD student advised by Dr. Julio Alvarez. Eliana’s PhD is focusing on the application of quantitative tools for the management of problems of relevance to the swine industry at both the farm and population (i.e., supra-farm) levels. She is currently focusing on developing systems to quantify the effect of endemic diseases such as swine influenza and the management strategies adopted for their control in affected farms. She is also working on the assessment of trends in submissions received at veterinary diagnostic laboratories over time to evaluate the impact of changes in disease distribution, diagnostic approaches and farm management in the U.S.

jose_angulo Dr. Jose Angulo is receiving the Allen Leman fellowship. Jose obtained his DVM degree in Mexico and is currently a PRRS specialist and managing veterinarian for Zoetis in charge of U.S. customers. Jose will be completing his Masters in Dr. Montse Torremorell’s lab and his work will focus on understanding PRRS infections in growing pigs and how to prevent them.

Science Page: Incidence risk and incidence rate

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week’s Science page is a follow-up from the one presented last week and focuses on the difference between incidence rate and incidence risk. Those two epidemiological measurements are often mistaken for one another.

Key points from this week edition:

  • Incidence risk is a measure of disease occurrence over a defined period of time. It is a proportion, therefore takes values from 0 to 1 (0% to 100%).
  • Incidence rate takes into account the time an individual is at risk of disease. It is not a proportion since it defines the number of cases per animal or farm time at risk.
  • Incidence risk and Incidence rate are often confused. Incidence risk and rate are numerically the same when the period at risk does not vary across individuals being studied.

Take a look at the complete report to see an example of the difference between incidence risk and incidence rate on farms.

 

Metabolites, antibiotimicrobials, and gut microbiome

salmonella.jpg
Salmonella Bacteria, Source: NIAID

In this article published by the National Hog Farmer, nutritionists and microbiome analysts from the University of Minnesota discuss what consequences antimicrobials can have on the gut microbiome.

What does microbiome mean?

Microbiome refers to all of the microbes present in an area. For example, gut microbiome is the entire population of microorganisms (most of the time bacteria) present in the intestinal tract.

The purpose of this research program is to study the effects antimicrobials can have on the bacterial populations present in the gut and how those changes influence the metabolites present in the pig.

What is a metabolite?

Metabolites are usually small molecules and are created by enzymatic reactions happening through the natural life of a cell or organism.

One of the effects of administering tylosin to pigs was the increased growth of bacteria producing short-chain fatty acids in the intestinal flora. The use of this antimicrobial also led to the development of Lactobacillus in the gut.

Relating changes in metabolites to the gut microbiome allows for a more complete understanding and investigation of the impact that antibiotics have in enhancing growth. Without completely understanding the mechanism of increased growth, antibiotic alternatives could be used inappropriately without much added benefit.

Link to the full paper

Science Page: PRRS cumulative incidence by status

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

How does PRRS incidence vary based on farm status? This is the question answered in this week’s edition of the Science Page. Three different formulas were used to calculate the incidence in each of the group over type. First, the initial number of farms of each status at the beginning of the year was used as the denominator. Then, the denominator was changed to the total number of farms that entered each status since the beginning of the year. Lastly, weekly incidences calculated for each of the group since the beginning of the year were added. Calculations went back for the last 3 years.

Key points from this week edition:

  • Cumulative incidence is higher in those farms that are under status 2, 2vx and 2fvi.
  • The incidence is lower in farms that had recently an outbreak or those that are completely negative.
  • Different ways of calculating incidence by herd status lead to the same overall conclusion.

Take a look at PRRS incidences in farms of group 2 status, vaccinated or inoculated with live virus over the past years.

Obituary for Dr. Bob Morrison

05-16-4001a
Credits: National Hog Farmer

Morrison, Robert (Bob) of Roseville, MN, died tragically in a car accident on May 2, 2017 at age 64 while traveling in the Czech Republic.

He is survived by wife Jeanie Morrison, three children, Jessie (Eric) Bain, Peter (Eva) Morrison, and William Morrison, and grandson Ian Bain.

A man of the utmost integrity, Bob was a beloved father, husband, grandpa, uncle, brother, father-in-law, brother-in-law and friend. He was honest, hard-working, loyal, open-minded, grateful, genuine and humble. Bob was a kind man with a gentle soul. Bob was a lifelong learner and born teacher.

He served as Faculty in the Department of Veterinary Population Medicine at the University of Minnesota since 1986. He was a brilliant data scientist and leader in his industry, guiding responsible vaccination and antibiotic use domestically and globally, responding to outbreaks and pandemics, and advocating for safe and ethical pork production.

Memorial contributions may be made to one of two organizations close to Bob’s heart:

  1. The University of Minnesota Foundation SquashScholars Scholarship (established by Bob and Jeanie) by mail to U of M Foundation, PO Box 860266, Minneapolis, MN, 55486-0266, or online at give.umn.edu/giveto/… (Tax ID: 41-6042488)
  2. Global Health Ministries (Project #79 AL -P0001) for Dr. Mark Jacobson’s HealthMinistries in Arusha, Tanzania by mail to 7831 Hickory St NE, Fridley, MN 55432 (Tax ID: 36-3532234).

Visitation will be at Falcon Heights United Church of Christ (1795 Holton St, Falcon Heights, MN 55113) on Thursday, July 6, 5:30-7:30 PM. Funeral Services will be at Roseville Lutheran Church (1215 Roselawn Ave W, Roseville, MN 55113) on Friday, July 7, 7 PM.