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Zoo biology [journal]
- Effect of concentrates restriction on feed consumption, diet digestibility, and nitrogen utilization in captive Asian elephants (Elephas maximus). [JOURNAL ARTICLE]
- Zoo Biol 2014 Dec 16.
In order to study the effect of concentrates restriction on feed consumption, diet digestibility, and utilization of nitrogen in captive Asian elephants (Elephas maximus), two feeding trials were conducted on three juveniles, four sub-adults, and three adults. During trial I, the conventional zoo diets of juveniles, sub-adults, and adult contained 22, 17, and 16% of concentrates on dry matter (DM) basis, respectively. During trial II, the amount of concentrate was reduced by 50%. A digestion trial of five days collection period was conducted during each period. The animals ate more roughages when concentrates were restricted. Intake of DM (g/kg BW(0.75) /day) was highest in sub-adults, followed by juveniles and adults. Apparent digestibility of crude protein (CP), neutral detergent soluble (NDS), and supply of digestible energy (DE) was highest in juveniles, followed by sub-adults and adults. Based upon the estimated metabolic fecal nitrogen (MFN) and calculated endogenous urinary nitrogen (EUN) and dermal losses, minimum dietary CP required to meet maintenance requirement was estimated to be 6.12, 6.05, and 5.97% in juveniles, sub-adults, and adults, respectively. Restriction of concentrates resulted in decreased (P < 0.05) digestibility of DM and GE, but the diet still supplied adequate amounts of DE and CP to fulfill estimated requirements of energy and protein during the period of experimentation. Thus, the concentrates portion of the diets of captive Asian elephants should be fed in a restricted way so as to reduce the intake of excessive calories and the potential risk of obesity. Zoo Biol. 9999:1-11, 2014. © 2014 Wiley Periodicals, Inc.
- Behavior and body mass changes of a mother and calf Pacific walrus (Odobenus rosmarus divergens) during the suckling period. [JOURNAL ARTICLE]
- Zoo Biol 2014 Dec 15.
The behavior of a 13-year-old female Pacific walrus and her first calf is described during the first 7 months of the 19-month suckling period. The calf vocalized before 62% of suckling sessions. The mother immediately responded after 84% of vocalizations; after 44% she allowed a suckling session. The number of suckling sessions per 24-h period decreased from on average nine in the second week after birth to two by the thirteenth week. Thereafter, the number of suckling sessions fluctuated between 3 and 5/day. The average suckling session duration increased from 4 min/day to around 17 min/day. The average effective suckling time per session increased from on average 2 to 10 min. The number of breaks decreased during the study period from around 40 to 20 per session. The mother spent on average 47% of her time resting, the calf 44%. The remaining time was spent in locomotion, and suckling, playing, investigating, and looking. Mother and calf spent on average 51% of time indoors. The mother spent 43% of her time in the water, the calf 39%. The calf's body mass at birth was 55 kg; it increased to 178 kg at 27 weeks. The mother did not eat for the first 5 days after delivery, and she ate less than usual during the next 6 days. The mother's mass eventually stabilized at 1024 kg (>before gestation). The calf was not given formula and was weaned onto fish. This is the first detailed description of a captive Pacific walrus's suckling period. It could benefit the husbandry of future captive-born walruses, and may elucidate the behavior of wild walruses during suckling. Zoo Biol. 9999:1-11, 2014. © 2014 Wiley Periodicals, Inc.
- Life expectancy and longevity of varanid lizards (Reptilia:Squamata:Varanidae) in North American zoos. [JOURNAL ARTICLE]
- Zoo Biol 2014 Dec 11.
In zoos, life expectancy-the average lifespan of individuals within a population, and longevity-the maximum lifespan within a population, can be useful parameters for evaluating captive husbandry and animal welfare. Using life history and demographic data derived from regional studbooks, this study examined life expectancy and longevity in a total of 782 wild-caught (WC) and captive-bred (CB) varanid lizards of seven species maintained in North American zoos since 1926. The average lifespans for WC and CB animals were 6.3 ± 0.3 and 9.3 ± 0.4 years, respectively, with CB males living significantly longer than females (P = 0.009). A total of 26.4% of WC and 22.5% of CB animals experienced mortality during their first 2 years in captivity, with mortality during this period greatest among Varanus rudicollis and V. prasinus. A positive correlation was observed between life expectancy and adult body mass in captive-bred individuals (r = 0.981; P = 0.002). Wild-caught females with a history of successful reproduction had a significantly greater average lifespan than non-reproducing females (P < 0.0001). Results from this study suggest that varanids have not been reaching their lifespan capacities in North American zoos. In light of these findings, several husbandry-related factors which may be affecting the welfare and lifespans of varanids in zoos are identified and discussed. This study also highlights the utility of demographic and life history data in captive animal management, and offers a general framework for future herpetological studies of a similar nature. Zoo Biol. © 2014 Wiley Periodicals, Inc.
- Effect of bungee-carcass enrichment on behavior and fecal glucocorticoid metabolites in two species of zoo-housed felids. [JOURNAL ARTICLE]
- Zoo Biol 2014 Dec 9.
Enrichment can improve animal physiological and psychological well-being. This study sought to promote more natural felid behavior and prevent development or incidence of stereotypies through the use of a feeding enrichment. Our objectives are to use fecal glucocorticoid metabolites values and behavioral observations to quantify the effectiveness of the enrichment device for two species of large cats, Bengal tiger (Panthera tigris tigris; n = 2) and cougar (Felis concolor; n = 2). The feeding enrichment, a white-tailed deer carcass flank securely attached to an AussieDog Products(©) Felid 120-cm bungee, was implemented twice for each individual separated by 1 month. Fecal samples were obtained from each felid and analyzed for pre- and post-enrichment fecal glucocorticoid metabolites (FGM) concentrations using a cortisol enzyme immunoassay. An ethogram with 12 mutual exclusive behavioral categories was utilized to record behavioral responses to the enrichment. Results demonstrate that: 1) there were no differences (P > 0.05) in FGMs for either species between pre- and post-enrichment; 2) pacing decreased (P = 0.025) and walking increased (P = 0.017) after exposure to enrichment in both cougars; and 3) tigers reduced (P = 0.025) 'other' behavioral category after the first enrichment exposure and laid down more (P = 0.025) after the second enrichment exposure. The neutral hormonal impact on the animals coupled with the behavioral changes indicates that this enrichment is successful at altering the animals' behavior without adding physiological stress to their environments. These findings, combined with the low cost and versatility of the enrichment, promote the use of this enrichment to enhance large felid enclosures. Zoo Biol. 9999:1-8, 2014. © 2014 Wiley Periodicals, Inc.
- Evaluating the role of temperature in the reproduction of the yellow stingray (Urobatis jamaicensis). [JOURNAL ARTICLE]
- Zoo Biol 2014 Dec 9.
We conducted a temperature-dependent reproductive study on Yellow Stingrays (Urobatis jamaicensis) at the John G. Shedd Aquarium, Chicago, Illinois. A group of eight and six female rays were mated in 22°C ("cold") and 27°C ("warm") water, respectively, over a two-year period. Mating behavior, gestation length, pup yields, body condition indices, and activity levels were compared throughout both temperature trials. Mating behavior (e.g., pre-copulatory pursuits and behavior) did not differ between temperature trials. Cold trial gestation was incomplete and yielded no pups, while the warm trial resulted in three successful births and one stillborn birth. Body condition indices and overall activity were significantly decreased in the cold trials. These data suggest consequences for rearing Yellow Stingrays in cooler water and should aid in successful reproduction of U. jamaicensis at zoos and aquariums. Zoo Biol. 9999:1-7, 2014. © 2014 Wiley Periodicals, Inc.
- Ascaris spp. and Capillaria caudinflata infections in captive-bred crested ibis (Nipponia nippon) in China. [JOURNAL ARTICLE]
- Zoo Biol 2014 Dec 8.
Crested ibis (Nipponia nippon), an endan gered native bird, was called the "precious stone" of oriental birds. N. nippon was considered a critically endangered species in the IUCN Red List of Threatened Species and a first-class national protected animal in China. The Chinese government had exerted considerable effort to protect the N. nippon population. An effective approach to increase the number of these birds was captive breeding. However, several pathogens, including parasites, could jeopardize the health of this species. The present study used the fecal flotation method to determine prevalence of intestinal parasites in fresh stool samples by wet mount smearing and iodine staining. Samples were obtained from 63 randomly selected crested ibis bred in Shaanxi Rare Wildlife Rescuing and Breeding Research Center in Zhouzhi County, Xi'an City, Shaanxi Province, China. In the 63 captive individuals, 38 were found positive for intestinal parasites (60.3%, 38/63). Of positive birds, high prevalence of Ascaris spp. (84.2%, 32/38) and Capillaria caudinflata (50.0%, 19/38) were detected. Coccidea (7.8%, 3/38), Fasciolidae (23.7%, 9/38), Blastocystis spp. (15.8%, 6/38), and Entamoeba histolytica (7.8%, 3/38) showed relatively low prevalence rates. This study focuses on the morphological identification of Ascaris spp. and C. caudinflata and their transmission in the N. nippon population. We introduce strategies to improve the breeding management of the birds, enhance their health, and stimulate population productivity. Zoo Biol. XX:XX-XX, 2014. © 2014 Wiley Periodicals, Inc.
- In memoriam. [Journal Article]
- Zoo Biol 2014 Nov; 33(6):592.
- Capture, transport, and husbandry of elephant sharks (Callorhinchus milii) adults, eggs, and hatchlings for research and display. [JOURNAL ARTICLE]
- Zoo Biol 2014 Nov 14.
Elephant sharks (Callorhinchus milii) have the slowest evolving genome of all vertebrates and are an interesting model species for evolution research and a prized display animal. However, their deep water habitat, short breeding season, fragility, and susceptibility to stress-induced mortality have made them difficult animals to capture, keep in captivity, and obtain fertilized eggs from. Gravid females were captured by rod and reel from Western Port Bay, Australia and transferred to a 40 000 L closed aquaculture system to lay their eggs before being released. The water quality parameters, averaged over three seasons of 4-6 weeks (mean ± standard deviation) were: 16.8°C ± 2.31, salinity 37.1 ± 2.9 g/L, ammonia 0.137 ± 0.2 mg/L, nitrite levels 0.89 ± 0.9 mg/L, nitrate 66.8 ± 45.6 mg/L, pH 7.8 ± 0.18, dissolved oxygen levels 93.6 ± 5.3%, ORP 307 ± 63.3 mV. Eggs were incubated in purpose-built egg cages and embryos hatched after 143.6 days ± 1.3 at 16.9 ± 0.9°C of incubation. These procedures led to no adult mortality in the last 2 years and 620 eggs with known deposition date were collected over 4 years, of which 81.5% (±4.8) were viable. Collection of abundant embryological material with known deposition date is of paramount importance for evolutionary developmental research. We attribute this success to excellent water quality, maximum reduction of stress during capture, transport, handling, and captive care. Zoo Biol. XX:XX-XX, 2014. © 2014 Wiley Periodicals, Inc.
- Assessment of the reproductive status of female veiled chameleons (Chamaeleo calyptratus) using hormonal, behavioural and physical traits. [JOURNAL ARTICLE]
- Zoo Biol 2014 Nov 13.
Egg binding is a common reproductive disorder in captive female reptiles leading to premature loss of breeding potential, or in severe cases death. It can result from failure to ovulate (and reabsorb) follicles; follicular stasis, or failure to lay eggs; dystocia. Reproductive status of female veiled chameleons (Chamaeleo calyptratus) in a research colony was assessed using enzyme immunoassay (EIA) of fecal reproductive hormones (estradiol; E2, progesterone; P, and testosterone; T) and their metabolites, ultrasound imaging of the reproductive tract, and receptivity to conspecific males. Periods of follicular growth (vitellogenesis) corresponded with increasing levels of E2, and following ovulation, a distinct change in morphology from round (follicles) to oval (eggs) structures, which was accompanied by a surge in P (>20-fold above baseline). P levels remained elevated throughout the gravid phase until just prior to oviposition. Length/width ratios of follicles and eggs were statistically different, but distinguishing a follicle from an egg based on the ratio was unreliable due to a large overlap in values. In animals that failed to ovulate on their first cycle, follicles began to recede but were not fully reabsorbed and could be distinguished from a second batch of follicles based on their echogenicity. Female receptivity to conspecific males was not related to cycle stage (i.e., previtellogenesis, vitellogenesis, or gravid) or reproductive hormone levels. This study demonstrates the use of ultrasonography and reproductive hormone analysis to assess phase of the reproductive cycle (pre- or post-ovulatory), or confirm ongoing follicular stasis. Zoo Biol. XX:XX-XX, 2014. © 2014 Wiley Periodicals, Inc.
- First observations of fertilized eggs and preleptocephalus larvae of Rhinomuraena quaesita in the Vienna Zoo. [JOURNAL ARTICLE]
- Zoo Biol 2014 Nov 10.
For the first time worldwide, fertilized eggs of ribbon eels (Rhinomuraena quaesita) hatched into feeding preleptocephali and could be kept alive for a period of seven days in the Vienna Zoo. The study reports on husbandry, behavioral observations and dimensions of eggs and preleptocephalus larvae. Furthermore, body color variations of ribbon eels in captivity do not reflect its sex or sexual maturity. Zoo Biol. XXXX:1-4, 2014. © 2014 Wiley Periodicals, Inc.