ASGV Forum Comparison of Cage Size and Activity Levels in Young Captive Sugar Gliders (Petaurus Breviceps) David M. Brust, DVM Abstract Young Sugar Gliders (known as Joeys) have an instinctual fear of falling, and become significantly less active when they cannot firmly grasp their surroundings. This trial was designed to compare common cage sizes and construction materials; and investigate their relationship to stress and activity levels in young Sugar Gliders. The study showed that the Joeys did the best when: 1) started out in a smaller starter cage specifically designed to match their physical capabilities - and then 2) progressively moved into larger cages as they grew and matured. It was also shown that Joeys did not do well in bird cages, that they were significantly more active in a cage that utilizes a significant number of horizontal bars. Sugar Gliders (also commonly known as Sugar Bears and Honey Gliders) have rapidly been gaining popularity in the United States as household pets. Stress is one of the most common causes of serious health issues in young Joeys under 5 months of age out of pouch (OOP). Typical manifestations include: self-mutilation, diarrhea and bacterial or protozoal enteritis, fur pulling or alopecia, eating disorders (coprophagy, hyperphagy, polydipsia, and cannibalism. Another common symptom of stress is a significant reduction in nocturnal activity levels. Reducing stress and increasing activity levels are especially important to the health and well-being of young Sugar Gliders. The most common causative factor of stress in Joeys is being picked up by their new owners several times a day in order to facilitate bonding. Bonding with Joeys is most effective when they are adopted between the ages of 7-12 weeks OOP. During this bonding period, it is necessary to pick up and handle the Joey (either directly or in a bonding pouch) between 1-4+ hours per day. To reduce stress, picking them up while sleeping is typically recommended. However, for most new owners this is not
a realistic expectation; since most Joeys awaken almost immediately upon the slightest touch. Sugar Gliders are extremely fast and nimble, and once they are awake most new owners are not able to easily grasp them. The ensuing chase and capture are extremely stressful on both the animal and its owner. The primary methods to avoid these situations are: 1) utilizing proper capture techniques, 2) housing Joeys in a cage where they cannot easily escape their owner s reach, and 3) avoiding the use of multiple toys, branches or other obstructions inside the cage during the initial bonding period. Sugar Gliders are often housed in aviarytype bird cages which vary greatly in size. Cages are typically constructed of either vertical bars, horizontal bars, or a combination of both. Common materials/processes used to finish cage bars include: paint, epoxy, powder-coating and galvanization. Materials and Methods Two separate 10 day trials were conducted as a part of this study. In both trials, the animals were maintained in close audio, visual and olfactory proximity. Cages contained a drip water bottle, 2 feeding dishes, and a nesting cloth / heat rock. Room temperature was maintained between 70-75F (21-24C) with a supplementary heat source and a natural light cycle. Trial #1 sought to examine whether Sugar Gliders naturally prefer to climb using horizontal or vertical bars. In this trial, ten young Sugar Gliders (8-12 weeks out of pouch) were separately housed in PVC wire-coated cages measuring approximately 18 inches (46cm) in width & depth; and 24 inches (61cm) in height. The cage bars were a ½ x 1 (1.25-2.5cm) rectangular mesh. (See Figure 1) Each night at approximately 11pm, each joey s activity was remotely video-taped for precisely 1 minute. The videos were then reviewed in slow motion to examine each individual s vertical climbing habits and determine: 1) the number of horizontal grasps, and 2) the total number of grasps in that time period. Each video was examined twice to ensure accuracy. In ten days, this trial resulted in 8,584 total grasps in 100 total minutes of observation. Trial #2 sought to determine if a causative relationship exists between cage size/construction and activity levels in young Sugar Gliders. In this trial, thirty young Sugar Gliders (8-12 weeks out of pouch) were randomly separated into three, equal test groups. The first group of ten Joeys was individually-housed in 72x72x72 inch (2m x 2m x 2m) aviaries consisting of vertical bars spaced ½ inch (1.25cm) apart. The second group of Joeys was individually-housed in commercial 33x22x26 inch (84x56x66cm) aviaries available at many retail pet shops and websites and commonly used to Figure 1 Ideal Starter Cage for Young Joeys
house Sugar Gliders. (See Figure 2) These aviaries were constructed of ½ inch (1.25cm) spaced, powder-coated, vertical bars. The remaining ten Joeys were individually-housed in PVC wire-coated starter cages measuring approximately 18 inches (46cm) in width & depth; and 24 inches (61cm) in height. The cage bars were a rectangular mesh of ½ x 1 (1.25-2.5cm). (See Figure 1) Every night at approximately midnight, each Joey was observed for precisely ten minutes. Using Seiko SO58 digital stopwatches, all periods of non-activity (motionless) were recorded and totaled. The cumulative results of each observation were then rounded to the nearest second. In ten days, this trial resulted in 300 individual samplings over 50 hours of observation. Conclusions The first trial showed that the young Sugar Gliders instinctually preferred to grasp horizontally 82% of the time. (See Figure 3) Sugar Gliders, of any age, will do better in a cage constructed of a mesh material. The horizontal bars enable the Sugar Glider to move much easier and therefore be more active, which improves their health and well being. (See Figure 4) The second trial showed that the activity of the young Sugar Gliders decreased relative to the larger size of the cage. When the Joeys were placed in a smaller cage that was specifically designed to match their physical capabilities, they exhibited an 89% activity rate, as compared to a 28.6 % activity level in the largest cage. (See Figure 5) The use of mesh cage material and progressive cage sizes both add to the health and to the reduction of stress in the Sugar Gliders tested. Figure 2 A Standard Aviary Cage Figure 3 Natural Predisposition to Grasp Horizontally
FIGURE 4: Horizontal versus Vertical Bar Study 1 minute observation each night at 11pm 10-8 week OOP joeys in Starter Cage Day 1 Day 2 Day 3 Day 4 Day 5 Horizontal Total Horizontal Total Horizontal Total Horizontal Total Horizontal Total 1 68 84 67 85 73 88 67 82 66 80 2 70 88 70 86 76 92 71 90 67 87 3 73 90 67 80 71 86 68 83 69 84 4 66 80 74 90 66 85 70 86 72 88 5 72 88 70 85 68 82 72 87 73 91 6 67 82 73 89 76 83 66 80 75 85 7 66 80 72 91 67 95 69 85 73 92 8 69 85 69 87 66 80 71 88 66 83 9 65 82 72 90 72 88 72 85 79 84 10 74 90 74 88 68 83 72 84 72 87 690 849 708 871 703 862 698 850 712 861 Day 6 Day 7 Day 8 Day 9 Day 10 Horizontal Total Horizontal Total Horizontal Total Horizontal Total Horizontal Total 1 72 90 74 91 72 88 69 85 69 84 2 74 90 69 83 69 85 71 87 72 88 3 68 86 66 85 66 83 73 90 67 82 4 66 85 71 86 75 91 69 83 66 78 5 69 83 62 79 68 85 72 87 69 85 6 65 82 66 80 72 87 75 91 67 83 7 68 85 69 83 69 84 68 82 75 90 8 72 91 74 92 72 87 73 88 72 87 9 70 87 69 84 73 91 69 85 67 81 10 69 84 68 84 70 86 71 88 74 90 693 863 688 847 706 867 710 866 698 848 Total Horizontal Grasps: 7,006 Total Grasps: 8,584 82%
FIGURE 5: Activity Level Study I. LARGE CAGE: (72x72x72 enclosure) based on 10 minute observations each night at midnight Seconds of Activity Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 1 162 163 166 181 189 164 178 186 177 168 2 188 165 170 172 178 185 173 164 189 166 3 172 178 173 192 165 178 165 174 166 181 4 168 167 180 173 157 169 178 183 194 192 5 162 164 167 188 174 182 168 189 168 172 6 178 192 163 179 178 168 162 169 163 164 7 173 189 172 164 167 180 171 159 171 174 8 169 171 180 166 163 165 181 174 159 168 9 173 178 161 171 174 164 170 180 173 141 10 162 155 167 161 158 175 164 163 159 176 28.6% II. MEDIUM CAGE: (33wx22dx26h Aviary) based on 10 minute observations each night at midnight Seconds of Activity Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 1 364 379 373 409 345 370 403 422 399 378 2 390 371 382 387 401 371 391 369 401 383 3 374 401 391 352 371 381 370 393 374 354 4 366 376 407 390 351 398 402 376 352 393 5 386 369 375 404 392 381 377 364 383 382 6 402 384 365 373 404 381 353 382 363 389 7 390 403 387 369 378 408 386 356 383 393 8 379 384 406 372 363 370 401 382 356 378 9 388 401 374 386 391 374 384 407 391 376 10 363 345 403 361 351 393 368 366 384 386 63.5% III. STARTER CAGE: (18wx18dx24h starter cage) based on 10 minute observations each night at midnight Seconds of Activity Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10 1 563 511 541 526 509 498 553 518 514 501 2 513 532 525 571 501 519 563 588 558 531 3 546 522 536 542 561 521 547 519 561 523 4 526 561 547 498 522 562 520 548 524 512 5 516 528 568 546 496 533 562 527 488 535 6 541 519 527 564 549 492 529 511 530 544 7 562 538 514 525 562 531 499 535 513 519 8 546 563 542 519 528 569 541 501 539 549 9 532 539 567 523 513 520 561 548 503 531 10 544 561 526 541 549 518 538 569 546 559 89.0% Starter Cage vs. Large Cage: 68% increase Starter Cage vs. Medium Cage: 29% increase
About the Author. David M. Brust, DVM Dr. Brust is a 1984 graduate of the Texas A&M College of Veterinary Medicine, and has been a practicing exotic animal veterinarian for the last 25 years. He is the past president of the West Houston Veterinary Medical Association and host of the radio talk show Ask the Vet. Dr. Brust is the author of Sugar Gliders: A Complete Veterinary Care Guide. He has also published several clinical studies on sugar glider diet and husbandry and is actively involved in continuing clinical research. He currently serves as the President of the Association of Sugar Glider Veterinarians (ASGV), and is also the editor of Sugar Glider DVM a biannual periodical dedicated to advancing veterinary knowledge of sugar gliders. An outspoken advocate for sound husbandry practices, Dr. Brust has filmed over 30 educational documentaries for the public regarding proper sugar glider care and husbandry. Dr. Brust is also a member of the American Veterinary Medical Association (AVMA), the Association of Exotic Mammal Veterinarians (AEMV), the Association of Avian Veterinarians (AAV), the Association of Reptilian & Amphibian Veterinarians (ARAV), the Texas Veterinary Medical Association (TVMA), and the American Veterinary Dental Society (AVDS). Address correspondence to: Dr. David Brust, c/o The Association of Sugar Glider Veterinarians, 935 Eldridge Road #218, Sugar Land, TX 77478. E- mail: drdave@thesugarglidervet.org