Environmental stimulation for domestic cats is important in minimizing stress, which can lead to negative behaviors, and development of disease. There are several recommended methods for feline environmental enrichment, but despite recognition of its importance, olfactory stimulation is often overlooked.
The effect of Nepera cataria, or catnip, is well known. The plant releases a chemical called nepetalactone, identified as the active cause of the euphoric response in cats. However, only around two out of three domestic cats are sensitive to the compound. The majority of big cat species have also been found to respond to nepetalactone’s. Tigers appear to be an exception to this. As nepetalactone is not thought to have any long term or harmful effect, it may be a useful enrichment tool for both domestic cats and big cats in captivity.
Catnip is the only plant containing nepetalactone. Actinidia polygama, or silver vine, is commonly used as a cat stimulant in Japan and has been found to release several active compounds similar in structure to nepetalactone. Anecdotal reports of other plants which stimulate cats include Tatarian honeysuckle, valerian root, and the fresh roots of the Indian nettle Acalypha indica. Data on the effects of these plants is scarce, although some similarities in the structure of the chemicals released have been identified.
In a recent publication in BMC Veterinary Research, Dr Sebastian Bol, molecular biologist and owner of the Cowboy Cat Ranch in Texas teamed up with several southern California cat clinics to test three additional plants – silver vine, Tatarian honeysuckle and valerian root.
One hundred cats were given catnip, silver vine, Tatarian honeysuckle and valerian root, by rubbing the plant matter on a sock or square of carpet and leaving it in the cat’s line of sight. After much patience and careful monitoring, the responses to each of these plants were assessed. A positive response was graded based on a variety of behaviors, including sniffing, licking, rolling, drooling and rubbing. A negative response was determined by no reaction following a minimum of two exposures to the plant. The most popular plant was found to be silver vine, with 80% of the cats showing a positive response – a higher response rate when exposed to Catnip.
Cats did not appear to favor one plant over another based on gender, age or behavioral category. Interestingly, some cats which didn’t react to catnip would react to one of the other stimulants, with 23 of the cats in the study responding to all four plants. Of the one hundred cats used in this study, only 6 did not respond to any of the compounds.
As silver vine and catnip were found to be the most popular in domestic cats, their effects were then assessed in 9 tigers and 5 bobcats at a Florida big cat sanctuary. As expected, the tigers did not respond well to the catnip, with only 1 of the 9 tigers showing interest. When presented with silver vine, almost half of the tigers were actively disapproving and would back away; however, none of the tigers showed a positive response. Contrastingly, the bobcats acted more like the domestic cats when shown silver vine, with 4 out of the 5 responding positively. Only 1 bobcat demonstrated a positive response to the catnip.
Although the study does not determine what causes the ‘catnip’ effect in some cats, the results of this study may be of use to cat owners. Those whose feline companions do not respond to catnip should know that there are alternative olfactory enrichment options available. The use of such plants may be useful in improving quality of life for cats; not only in the home, but also cats placed in potentially stressful environments such as veterinary surgeries, and enrichment of non-domesticated felines in zoos.