Positive Reinforcement Conditioning as a Tool for Frequent Minimally Invasive Blood and Vaginal Swab Sampling in African Lions (Panthera Leo)

Abstract

Information regarding the physiology of African lions is scarce, mainly due to challenges associated with essential routine research procedures. The aim of this experiment was to test the possibility of training six captive lionesses by positive reinforcement conditioning (PRC) to voluntarily allow the collection of vaginal swabs and blood samples. This was done with the final goal of avoiding frequent anesthesia, and potential stressful management during research. All lionesses mastered basic clicker and targeting principles within two weeks. Routine sampling was possible after 20 weeks of training, enabling collection of about 750 vaginal swabs and 650 blood samples over the course of the study (18 months). These samples served to describe in detail the African lioness' ovarian cycle by combination of behavioral observations, longitudinal steroid hormone monitoring, and vaginal cytology. They also helped establish the ideal time for ovulation induction and artificial insemination of lionesses presenting natural estrus. The animals remained calm and cooperative during all sessions, and demonstrated curiosity in the training. PRC training of captive lionesses proved to be a suitable, minimally 1 invasive method for repeated collection of vaginal swabs and blood. Additionally, PRC may serve as behavioral enrichment for African lions in captive settings. Compared to chemical or physical restraining methods, this non-invasive management approach may reduce distress and physiological negative side effects, thus opening up new avenues for feline research.

Positive reinforcement conditioning as Sumatran tiger's (Panthera tigris sumatrae) social enrichment at Tambling Wildlife Nature Conservation Rescue Centre, Lampung, Indonesia

“…Its implied PRC could minimize distress during blood collection on the tiger. This is consistent with other research (Callealta et al 2019), which successfully conducted PRC on African lions.…”

“…Fresh chicken meats were chosen as a food reward on PRC (Callealta et al 2019). The fresh chicken meat was parted into 12 pieces.…”

“…Positive reinforcement conditioning (PRC) using food "rewards" prepares the animal to voluntarily cooperate during blood collection/vein puncture (Coleman et al 2008). PRC reduces stress during blood collection on antelope, bison (Grandin 2000), dog, andwolf (Vasconsellos et al 2016) and applies to snow leopards (Broder et al 2008) lions (Callealta et al 2019) and jaguar (Gracia et al 2021). Negative reinforcement as "punishment" has been mentioned on the rat (Mayer et al 2018;Hernandez-Lallement et al 2020) and dog (China et al 2020).…”

Effects of positive reinforcement training for heifers on responses to a subcutaneous injection

“…Other research indicates that this approach could work. For example, Callealta et al (2020) reported that captive lionesses, once trained with positive reinforcement, could be subjected to repeated blood draws and vaginal swabs without restraint and while maintaining their cooperation.…”

Obtaining Ejaculates through Operant Conditioning of the Golden Eagle (Aquila chrysaetos)

“…efficiently (McGreevy et al, 2014;Callealta et al, 2019). Additionally with assisted reproduction in birds, it contributes to the conservation of many species (Sami, 2015).…”