Forty-eight students were recruited to do a simple task: Playing a Japanese children's game that, from the paper, sounds a lot like the American board game Operation. They had to drop various body pieces into holes without touching the edges.
Students did this in a few conditions: After seeing a pictures of baby animals (puppies and kittens), after seeing adult animals (dogs and cats) and after seeing pleasant foods (steak, sushi and pasta). Far and away, productivity was best in the first condition - you can see this in the chart below. This was true across both genders participating in the experiment.
Students may have also become more attuned to fine movements.
Caring for babies (nurturance) not only involves tender treatments but also requires careful attention to the targets’ physical and mental states as well as vigilance against possible threats to the targets. If viewing cute things makes the viewer more attentive, the performance of a non-motor perceptual task would also be improved.
You can read the full study here. But, more importantly - and strictly for productivity-enhancing purposes - you might just want to check out these photographs of newborn red pandas. And there's also this Washington Post animal pictures gallery if you're looking for an even bigger boost.