Researchers discovered that neonatal piglets are capable of being trained in traditional learning and memory tests. As a result, these piglets can provide critical information that could directly benefit human health.
"Studies suggest that inadequate nutrition, stress, and infection leave fingerprints in early brain development that can make a person more vulnerable to behavior disorders later in life," said Rodney Johnson, U of I professor of animal sciences and director of the Division of Nutritional Sciences. "We are interested in learning how the brain develops during this time and how cognitive ability is affected. Our goal is to understand how to promote optimum brain and cognitive development, and minimize potential experiential influences that might hinder the process."
The use of the pig in neuroscience research is gaining popularity because pigs are anatomically similar to humans and many of their organ systems grow and develop similarly as well. Pigs are also precocial, meaning they are born with well-developed sensory and motor systems. This allows them to be very mobile and weaned at an early age.
"Most important, the pig brain's growth spurt occurs perinatally – a little before and a little after birth," Johnson said. "In contrast, the rodent's brain growth spurt occurs after birth and the non-human primate's occurs before birth, making them less ideal to study and compare to humans."
The brain's rapid growth spurt is a critical period of time, Johnson said.
"We know that if something goes wrong during this developmental period, the brain can be permanently altered," he said. "We believe that events occurring during this developmental period may underlie some of the behavioral problems that emerge later in life."
In the study, piglets were weaned from their mothers at 2 days of age and set up with a milk system that delivered 14 small meals a day – mimicking the number of meals they'd receive from their mother.
At two weeks of age, piglets were trained to locate a milk reward in an 8-arm radial maze, a large version of models typically used to study rodent behavior. The eight arms of the maze were equipped with a cup exactly like the cup piglets fed from during the day. Seven of the bowls contained inaccessible milk and one bowl contained milk that was accessible. The goal was to teach the piglets how to find the accessible bowl of milk.
Piglets can't utilize extra-maze cues (such as a picture on a wall) like mice do because pigs tend to keep their nose to the floor. In order to create cues, researchers covered the opening of each maze arm with a blue or white curtain. The piglets learned color cues to remember where to find milk. In the first test, the blue curtain contained the bowl with milk.
"The piglets learned quickly after day one where to find their reward," Johnson said. "This simple associative learning task was not hard for them to complete.
"But then, we did a reversal learning test where the white curtain became the entrance to the cup of accessible milk. This was more complicated because the piglets had to learn to stop going to the blue and then associate white with milk. It required a greater cognitive load, but it was one that they learned over time."
Researchers also investigated how peripheral immune activation affects cognitive processing. One group of piglets received an immunostimulant to mimic a common viral infection. These pigs experienced cognitive deficits, requiring more time to complete the reversal learning test.
"When the immune system encounters an infectious agent, it responds and conveys information to the brain," he said. "We were able to show that when the peripheral immune system conveyed information to the brain in the neonate, their cognitive abilities were hindered. That reveals another advantage of the neonatal piglet model."
The viral mimetic also increased pro-inflammatory cytokines in the hippocampus, a brain area involved in certain types of learning and memory. Pro-inflammatory cytokines in the hippocampus inhibit memory consolidation, making it more difficult to learn, Johnson added.
The Johnson lab is currently using MRI imaging to study brain development in piglets from two weeks of age until the piglets reach sexual maturity or an adolescent stage.
Results of this research project, "Behavioral assessment of cognitive function using a translational neonatal piglet model," were published in Brain, Behavior, and Immunity. Researchers included Rodney Johnson and Ryan Dilger, both of the University of Illinois.
Jennifer Shike | EurekAlert!
Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University
New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine