Jaguar Genetics

This female jaguar, Zassi, is enjoying a fish embedded Popsicle at the Jacksonville Zoo and Gardens. She is wild-born, on loan from the country of Guyana, South America, and extremely important to the Species Survival Plan (SSP) population. She had a single male offspring on the first of January, 2009, and if he breeds, Zassi will be a "founder." Ideally, she will need to produce four offspring that all contribute offspring, thus, mathematically, 93.75% of her genetic material will pass on to the captive population.

The Jacksonville Zoo and Gardens has a long history with jaguars, including the prolific Zorro, a black male from the early seventies, who passed on his melanistic gene into the population. (All black jaguars in this country can be traced back to Zorro.) In 1998, the zoo imported 1.2 (one male and two females) jaguars from Venezuela. This was the first time wild-born jaguars had been brought legally into the US in well over a decade.

At that time, the scientific community believed that there were at least three and maybe four different subspecies of jaguars represented in Venezuela. The Zoo was very careful to select three animals that originated from the same part of the country (the Llanos), so that they would be "pure."

Unfortunately, the male had no interest in breeding and there have been no offspring from any of the Venezuela cats. As it turned out, the efforts to identify animals from one region were not necessary. Newer DNA evidence shows that there are eight subspecies of jaguar and only one from Venezuela: Panthera onca onca.

The two surviving Venezuelan jaguars are too old to breed naturally, but the Zoo has not given up on them. The veterinary department has been collaborating with scientists on artificial insemination and in vitro fertilization. This cutting edge research is providing answers to many questions about the reproductive physiology of the jaguar.

Photo by D. Bear-Hull

Pronghorn Antelope Exam

The Lee Richardson Zoo in Garden City, Kansas was well known for its productive pronghorn antelope herd when I worked there several years ago. Every year, the group was caught up for annual exams, a process that was as efficient and stress-free as possible. Unlike a scenario using chemical tranquilizers, the Kansas pronghorn were processed by bold, experienced keepers who knew how to move quickly and firmly.

The first photo is of the "catch" crew who enter an empty stall where a single animal has been shifted (each antelope is separated to be worked; the rest of the herd is visually separated and remains calm). The catch team use a "baffle" board, which can be seen in the middle left. The baffle board is a four by eight foot sheet of plywood, with handles on one side. It is used as a mobile squeeze chute, where, in seconds, the animal is pushed against the stall wall. Sometimes, pronghorns react to this by dropping to the ground, which this particular animal has done. Staff on the right are reaching down over the board to secure the head.

The second image shows the keepers quickly moving the animal outside of the stall. The head and feet are secured, although this animal was not really struggling. In the third photograph, the exam takes place in the hallway, with the barn doors closed. One of the secrets for hoofed stock handling was a thick mattress, which was comfortable for the animals (and staff!), and seemed to have a calming effect. Note that the head and legs are firmly held (here, the antelope's left front leg is the critical one that must be restrained to prevent her from standing) and that all staff work from behind the pronghorn, to prevent injuries from kicking.

The Lee Richardson zoo vet checked teeth, took blood, vaccinated, and examened each antelope. They were weighed and the hooves were trimmed. One of the benefits of annual checkups is that there can be incidental findings, such as the thick pus-like material oozing from above and between the claws of a hoof. It smelled strong and we all thought it was some kind of infection, possibly from a foreign body in the foot. A gentle squeeze of the other feet showed the same whitish ooze, in exactly the same place! The other pronghorn were similiar -- the material was natural, coming from a scent gland used to mark territory.

In addition to the nasty foot gland odor, pronghorn have a curious body smell that many found objectionable. To me, especially the male seemed sweetish, almost like he was drenched in maple syrup perfume. Pronghorn stiff, hollow (for insulation) hairs are coated with a brownish red oil. When they were worked up, this herd was shedding, so greasy hunks of hair came out by the handfuls, and stuck everywhere.

Everyone had a job to do, and the operation went smoothly. The average time on the mattress was five minutes, and four animals were processed in less than one hour. With experienced handlers, the hand restraint of selected species can be done safely and successfully. Another reason for the success with these particular pronghorn is that they were hand reared by keepers from one day of age and returned to the herd at two months of age. This "imprinting" technique reduced the startle reaction of a species that depends on sight to identify predators. The animals integrate successfully with the herd, and breed, but they do not react violently to people and man-made commotion.

The pronghorn, from the western North American plains, is the sole represenative of its family. It is known for its sprints of over 50 miles per hour and is theorized that a cheetah like cat, now extinct, would have preyed on the pronghorn. Both sexes have bone-cored horns that are shed every year. The pronghorn is known for its brilliant white rump patch which it erects to signal danger. It cannot jump fences, but chooses to crawl under them, and conservation-minded ranchers will use a smooth wire on the bottom rung of barbed-wire fences.