Petting zoos may have more critters than you realize, and some aren’t cute and cuddly. The zoos are sometimes home to multidrug-resistant bacteria that can be passed on to visitors.

Researchers at Ariel University in Israel studied eight petting zoos at random throughout their country, taking body surface and other samples from 42 species — 228 animals in all. They did genetic sequencing to determine the species of bacteria and look for genes that revealed the presence of two potent, drug-resistant bacteria.

They identified 35 different strains of bacteria, and 12 percent of the animals harbored at least one of the two drug-resistant bacteria. About a quarter of the identified bacteria came from the animals’ feathers or fur, the rest from the animals’ feces. The bacterial strains that were identified included two forms of e. coli — one that causes diarrhea and another that leads to urinary tract infections in humans.

There was another interesting finding: Animals treated with antibiotics were seven times more likely to harbor drug-resistant bacteria.

While some animals may have bacteria that can be transmitted to humans, the researchers also offered some perspective: Petting zoos can be emotionally engaging and highly educational for children. Zoo operators should develop a strict infection control and hygiene plan as well as a reasonable policy on antibiotic use among their animals.

In practical terms, that means having handwashing stations before and after petting animals, banning food and drinks and keeping antibiotic-treated animals away from visitors. With proper care, the benefits can outweigh the risks.