Making Babies
State-of-the-art reproductive technology ensures genetic diversity and healthy birthing for some of our most endangered species.
As we humans know, especially those who have visited a fertility clinic, bringing new life into the world can be complicated. Gabriela Mastromonaco, Ph.D., the Toronto Zoo’s Curator of Reproductive Programs and Research, and the only full-time reproductive physiologist in a Canadian zoo, works with frozen sperm and other reproductive materials from hundreds of animals from around the world to ensure genetically diverse and healthy populations. The goal of the “bio bank” is to maintain genetic diversity of dwindling species and combat the possibility of extinction. Mastromonaco and two permanent staff members collaborate with a rotating team of wildlife organizations, government departments, universities, other zoos and researchers to help conceive healthy offspring in a number of ways. “Fifty percent of our work is as a service lab, answering questions from staff at our zoo and other zoos around the world. One of the biggest questions is ‘Is she pregnant, and if so when should we prepare her for motherhood?’” says Mastromonaco. The other half of their time is spent doing research. “We are investigating sperm handling and insemination techniques in non-domestic species, many of which are endangered,” she explains. For instance, studies of chipmunks in Algonquin Park can help her understand other rodent species such as the endangered Vancouver Island marmot.
Mastromonaco, who came to the Zoo seven years ago, spends 50 percent of her time devoted to Canadian species including the wood bison and the Vancouver Island marmot. Partnering with agencies such as Environment Canada, she studies samples provided by wildlife biologists to examine reproductive and stress hormone levels to determine the reasons a population has become fragile. For several years, Mastromonaco and her team have been working with caribou biologists to check for pregnancies and determine if the herd is growing. “Pregnancies indicate a herd’s health and how robust the females are. If they don’t have enough food the number of live offspring will decrease,” she explains. In the 1980’s, the Zoo assisted with the reintroduction of the wood bison in Manitoba, but they have suffered from disease and now there are only 3,500 left in the wild. Concerned that the species may be lost altogether, Parks Canada and the University of Saskatchewan have collaborated with the Toronto Zoo to gather genetic material for long-term storage and eventual use for offspring production. “Our Zoo has 25 females that are disease free. It is one of the largest captive wood bison herds being managed for conservation purposes in the world. We are testing protocols on the females and perfecting the technique before it is implemented with wild populations,” says Mastromonaco.
She’s also keeping a keen eye on the two giant pandas, Er Shun and Da Mao, on loan from China. “Giant panda females are monoestrous, which means they only have one reproductive cycle per year. That is the only time the female is receptive to the male and it’s only for 24-72 hours.” The female’s scent, along with chirping and bleating sounds, tells the male she’s ready for business. Although natural breeding is preferable, giant panda successes in captiv- ity have been minimal. That’s where experts such as Mastromonaco step in. Artificial insemination has proved to be as effective as natural breeding with pregnancy rates close to 60 percent. With renewed conservation efforts and an increase in protected reserves and breeding programs giant panda numbers are estimated to be around 1,600, twice the number counted in the 1980s. Mastromonaco works with birds and mammals too endangered to be in exhibits, as their numbers are so low. Her office is in the ‘hidden Zoo’, a place the public normally does not see. “We have 22 loggerhead shrikes that we are studying in collaboration with Wildlife Preservation Canada to understand the factors affecting their survival. The birds were down to 20 breeding pairs in Ontario. We want to help them survive as a species and hope to produce enough young birds to eventually boost the wild population,” she explains. Although her job has difficult challenges, Mastromonaco is optimistic about the future. She believes every step towards healthy reproduction is a step towards species survival. “What we do provides hope for the next generation,” she says.