The relationship between plant-eating and hair evacuation in snow leopards (Panthera uncia)

Abstract

Although most felids have an exclusive carnivore diet, the presence of plant matter in scat has been reported among various species. This indicates that there may be an adaptive significance to the conservation of plant-eating behavior in felid evolution. Some studies have hypothesized that felids consume plants for self-medication or as a source of nutrition. In addition, it is thought that plant intake helps them to excrete hairballs, however, no scientific work has confirmed these effects. Thus, the objective of this study is to investigate the relationship between plant intake and hair evacuation in felid species. We selected snow leopards ( Panthera uncia ) as the study species because they have longer and denser hair than other felids. The behavior of 11 captive snow leopards was observed and scat samples from eight of them and two other captive individuals were analyzed. Snow leopards evacuate hair possibly by vomiting and excreting in scats. The frequency of plant-eating and vomiting and the amount of hair and plant in scat were evaluated. We found that the frequency of vomiting was much lower than the frequency of plant-eating. In addition, there was no significant relationship between the amount of plant matter contained in scats and the amount of hair in scats. Contrary to the common assumption, our results indicate that plant intake has little effect on hair evacuation in felid species.

Plant‐eating carnivores: Multispecies analysis on factors influencing the frequency of plant occurrence in obligate carnivores

“…Sugar cane‐derived fibers reduced the size of hairballs in the scat of domestic cats (Loureiro et al., 2014 ). However, cellulose, one of the main insoluble fibers, did not have such an effect (Loureiro et al., 2014 ), and plant intake had little effect on hair evacuation in captive snow leopards (Yoshimura et al., 2020 ). Owing to the aforementioned attributes of prey items, smaller carnivores are considered to be more tolerant to indigestible food items (Jethva & Jhala, 2004 ; Rühe et al., 2008 ).…”

“…Hoppe‐Dominik stated that leopards ( Panthera pardus ) may eat grasses to keep their digestive tract moving during starvation (Hoppe‐Dominik, 1988 ). However, captive snow leopards also ate plants regularly even though they were fed daily (Yoshimura et al., 2020 ), suggesting that starvation is not always the trigger for plant eating. Furthermore, it has been suggested that grasses are selectively eaten because they are free of secondary plant compounds, unlike those in other plant groups (Hoppe‐Dominik, 1988 ).…”

“…Some researchers believe that the presence of plant content is caused by unintentional intake (Avenant & Nel, 2002 ; De Villa Meza et al., 2002 ; Krofel et al., 2011 ), while others argue that there might be some advantages of plant eating (Hoppe‐Dominik, 1988 ; Sueda et al., 2008 ; Tatara & Doi, 1994 ; Xiong et al., 2016 ). Indeed, observational studies indicate that felids eat plants voluntarily (Montalvo et al., 2020 ; Yoshimura et al., 2020 ) both in the captivity and in the wild, which indicates that this behavior is relatively common and natural among felids. However, experimental studies suggest that cellulose intake can be disadvantageous, since it decreases dry matter and energy digestibility (Edwards et al., 2001 ; Prola et al., 2010 ).…”

“…( 2008 ) reported in a questionnaire survey of owners of dogs under one year of age that these dogs ate plants more frequently, and the authors suggested that plant consumption may be a way for individuals with low immunity to fight parasites and pathogens. Second is the hair evacuation hypothesis (Shultz, 2019 ; Yoshimura et al., 2020 ). Functional carnivores often ingest their own hair while grooming, as well as the hair of their prey.…”

“…Second is the hair evacuation hypothesis (Shultz, 2019;Yoshimura et al, 2020). Functional carnivores often ingest their own hair while grooming, as well as the hair of their prey.…”