An Adolescent Porcine Model of Voluntary Alcohol Consumption Exhibits Binge Drinking and Motor Deficits in a Two Bottle Choice Test

Abstract

Aims Alcohol is the most commonly abused substance leading to significant economic and medical burdens. Pigs are an attractive model for studying alcohol abuse disorder due to the comparable alcohol metabolism and consumption behavior, which are in stark contrast to rodent models. This study investigates the usage of a porcine model for voluntary binge drinking (BD) and a detailed analysis of gait changes due to motor function deficits during alcohol intoxication. Methods Adolescent pigs were trained to drink increasing concentration (0–8%) of alcohol mixed in a 0.2% saccharin solution for 1 h in a two bottle choice test for 2 weeks. The training period was followed by a 3-week alcohol testing period, where animals were given free access to 8% alcohol in 0.2% saccharin solution and 0.2% saccharin water solution. Blood alcohol levels were tested and gait analysis was performed pre-alcohol consumption, last day of training, and Day 5 of each testing period. Results Pigs voluntarily consumed alcohol to intoxication at all timepoints with blood alcohol concentration (BAL) ≥80 mg/dl. Spatiotemporal gait parameters including velocity, cadence, cycle time, swing time, stance time, step time, and stride length were perturbed as a result of intoxication. The stratification of the gait data based on BAL revealed that the gait parameters were affected in a dose-dependent manner. Conclusion This novel adolescent BD porcine model with inherent anatomical and physiological similarities to humans display similar consumption and intoxication behavior that is likely to yield results that are translatable to human patients.

The horizontal ladder test (HLT) protocol: a novel, optimized, and reliable means of assessing motor coordination in Sus scrofa domesticus

“…Additionally, the typical open field arena for pigs is orders of magnitude smaller than the typical foraging distance observed within an ethological setting, calling into question the ethological validity of this test ( Murphy et al, 2014 ). Assessment of gait using a treadmill often requires advanced equipment and facilities, which are generally cost-prohibitive and for which infrastructure is sorely lacking ( Boakye et al, 2020 ; Shin et al, 2021 ). Therefore, inexpensive apparatuses that are safe to use, and protocols which are easy-to-train, and which produce reliable and repeatable evaluations of motor behavior are critically needed for assessing motor impairment in pigs.…”

The Horizontal Ladder Test (HLT) protocol: A novel, optimized, and reliable means of assessing motor coordination inSus scrofa domesticus

“…Additionally, the typical open field arena for pigs is orders of magnitude smaller than the typical foraging distance observed within an ethological setting, calling into question the ethological validity of this test 17 . Assessment of gait using a treadmill often requires advanced equipment and facilities, which are generally cost-prohibitive and for which infrastructure is sorely lacking 16,17 . Therefore, inexpensive apparatuses that are safe, easy-to-train, and which produce reliable and repeatable evaluations of motor behavior are critically needed for assessing motor impairment in pigs.…”

“…Similarly, in the open-field test, the ability to measure locomotor behavior while inducing conflict in the emotional/arousal domains of behavior often yields conflicting results across replicate studies 13,14 . Additionally, the typical open field arena for pigs is orders of magnitude smaller than the typical foraging distance observed within an ethological setting, calling into question the ethological validity of this test 17 . Assessment of gait using a treadmill often requires advanced equipment and facilities, which are generally cost-prohibitive and for which infrastructure is sorely lacking 16,17 .…”

Alcohol Induced Brain and Liver Damage: Advantages of a Porcine Alcohol Use Disorder Model

“…These studies demonstrated that pigs voluntarily consumed alcohol to intoxication and showed withdrawal symptoms analogous to humans, which contrasts with non-augmented rodent models. In a recent study from our group, the effects of voluntary alcohol consumption on motor function were examined in a 2BC ( Shin et al, 2020 ). In this porcine model of binge drinking, high blood alcohol levels (BAL) were achieved by voluntary oral consumption and animals exhibited perturbation in gait parameters that were also affected in humans during alcohol intoxication.…”