Performance of conventional pigs and Göttingen miniature pigs in a spatial holeboard task: effects of the putative muscarinic cognition impairer Biperiden

Elise Gieling,Remco Willigenburg,Niels-Christian Ganderup,Welmoed Wehkamp,Franz Josef Van Der Staay,Rebecca E Nordquist

doi:10.1186/1744-9081-9-4

Abstract

BackgroundThe pig is emerging as a model species that bridges the gap between rodents and humans in research. In particular, the miniature pig (referred to hereafter as the minipig) is increasingly being used as non-rodent species in pharmacological and toxicological studies. However, there is as yet a lack of validated behavioral tests for pigs, although there is evidence that the spatial holeboard task can be used to assess the working and reference memory of pigs. In the present study, we compared the learning performance of commercial pigs and Göttingen minipigs in a holeboard task.MethodsBiperiden, a muscarinic M1 receptor blocker, is used to induce impairments in cognitive function in animal research. The two groups of pigs were treated orally with increasing doses of biperiden (0.05 – 20 mg.kg-1) after they had reached asymptotic performance in the holeboard task.ResultsBoth the conventional pigs and the Göttingen minipigs learned the holeboard task, reaching nearly errorless asymptotic working and reference memory performance within approximately 100 acquisition trials. Biperiden treatment affected reference, but not working, memory, increasing trial duration and the latency to first hole visit at doses ≥ 5 mg.kg-1.ConclusionBoth pig breeds learned the holeboard task and had a comparable performance. Biperiden had only a minor effect on holeboard performance overall, and mainly on reference memory performance. The effectiveness needs to be evaluated further before definitive conclusions can be drawn about the ability of this potential cognition impairer in pigs.

Highlights

Most preclinical studies in neurosciences are performed using rodents, in particular mice, the pig is increasingly being used as a model species because it can bridge the anatomical/physiological gap between rodents and humans [1,2,3]
If food can only be found in a subset of potential sites, two memory components can be distinguished and measured simultaneously: spatial working memory (WM) and reference memory (RM) [11]
RM performance improved across blocks of trials (Blocks of trials: F25,350 = 104.43, p < 0.0001), and while learning appeared to be slightly delayed in the Göttingen minipigs (Pig breed X Blocks of trials interaction: F25,350 = 1.44, p = 0.0811), both groups of pigs had a similar level of performance

Summary

Introduction

Most preclinical studies in neurosciences are performed using rodents, in particular mice, the pig is increasingly being used as a model species because it can bridge the anatomical/physiological gap between rodents and humans [1,2,3]. WM holds information that is relevant only within a specific trial, such as a list of locations that have recently been visited/explored. RM stores the general rules of a task It retains relevance across many trials and is trial independent, but learning task specific. The miniature pig (referred to hereafter as the minipig) is increasingly being used as non-rodent species in pharmacological and toxicological studies. There is as yet a lack of validated behavioral tests for pigs, there is evidence that the spatial holeboard task can be used to assess the working and reference memory of pigs. We compared the learning performance of commercial pigs and Göttingen minipigs in a holeboard task

Methods

Results

Conclusion