Like humans, hamsters have feelings. They can experience happiness, optimism, sadness and depression, but these cannot be easily determined. Hence, a test was conducted by Emily Bethell and Nicola Koyama of Liverpool John Moores University.
The study published in Royal Society Open Science explains that "cognitive measures may detect shifts in emotion not apparent from behavioural observation or traditional behavioural tests of emotion alone."
It was found out that hamsters that are given extra comfort like comfy hammocks, soft bedding materials, ledges, chew toys and snacks are happier that those that are not given extra perks. Those who lack these would even show signs of depression, the study says.
A "go/no-go" test was given to the hamsters where 30 trained captive-born male Syrian hamsters were to approach a drink station with sugar water at one location to obtain a reward and to avoid a drink at another location where there was an aversive or bad tasting liquid. Aside from that, the scientists also created ambiguous situations in which it was unclear to the hamster if they were given a sweet drink or a bad-tasting drink, Discovery News reported.
Prior to the test, some hamsters were raised with extra care while others were given basic care. Those that were given enrichment care shows optimism and responded well in the test.
The researchers explained: "So far, studies have revealed that manipulations presumed to create a negative state (such as disrupted housing conditions or dehorning in calves) lead to reduced responses (more 'no-go's) to the ambiguous probes. This negative shift in judgment bias is presumed to arise from a negative shift in underlying emotion state."
"Positive manipulations (e.g. addition of environmental enrichment) generally lead to increased responses (more 'go's) at one or more of the ambiguous probes. This is presumed to arise from positive shifts in judgment bias and underlying emotion state," they added.
It is the hope of the researchers that their work will "lead to improved welfare assessment across species."
