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Dean E Biggins - One of the best experts on this subject based on the ideXlab platform.
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Challenges to reestablishment of free-ranging populations of black-footed ferrets.
Comptes rendus biologies, 2020Co-Authors: Dean E Biggins, Jerry L GodbeyAbstract:The black-footed ferret (Mustela nigripes) of North America is critically endangered due in part to its extreme specialization on formerly stable and abundant prairie dogs (Cynomys). Its close relative, the Siberian polecat (M. eversmannii) seems to have been subjected to a varying environment that was not conductive to specialization. One source of environmental variation in Asian steppes was plague (caused by Yersina pestis), which was absent from North America. Introduction of plague to North America presents serious challenges to ferret recovery. Partial solutions to other biological and political problems have been found, resulting in improved production in captivity, increased survival post-release, and thriving populations in plague-free South Dakota.
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Evaluation of Five Pulicides to Suppress Fleas on Black-Tailed Prairie Dogs: Encouraging Long-Term Results with Systemic 0.005% Fipronil
Vector-borne and Zoonotic Diseases, 2019Co-Authors: David A. Eads, Dean E Biggins, Travis M Livieri, Jonathan Bowser, Kristina Broerman, Eddie Childers, Phillip Dobesh, Randall L. GriebelAbstract:Abstract Plague, a flea-borne disease, hampers efforts to restore populations of black-footed ferrets (Mustela nigripes), which occupy colonies of prairie dogs (Cynomys spp.) in North America. Plag...
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RESISTANCE TO DELTAMETHRIN IN PRAIRIE DOG (CYNOMYS LUDOVICIANUS) FLEAS IN THE FIELD AND IN THE LABORATORY
Journal of Wildlife Diseases, 2018Co-Authors: David A. Eads, Dean E Biggins, Travis M Livieri, Jonathan Bowser, Eddie Childers, Randall L. Griebel, Janet C. Mcallister, Cristi Painter, Lindsey Sterling KrankAbstract:Abstract Sylvatic plague poses a substantial risk to black-tailed prairie dogs (Cynomys ludovicianus) and their obligate predator, the black-footed ferret (Mustela nigripes). The effects of plague on prairie dogs and ferrets are mitigated using a deltamethrin pulicide dust that reduces the spread of plague by killing fleas, the vector for the plague bacterium. In portions of Conata Basin, Buffalo Gap National Grassland, and Badlands National Park, South Dakota, US, 0.05% deltamethrin has been infused into prairie dog burrows on an annual basis since 2005. We aimed to determine if fleas (Oropsylla hirsuta) in portions of the Conata Basin and Badlands National Park have evolved resistance to deltamethrin. We assessed flea prevalence, obtained by combing prairie dogs for fleas, as an indirect measure of resistance. Dusting was ineffective in two colonies treated with deltamethrin for >8 yr; flea prevalence rebounded within 1 mo of dusting. We used a bioassay that exposed fleas to deltamethrin to directly eva...
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Space use, resource selection and territoriality of black-footed ferrets: implications for reserve design
Wildlife Biology, 2014Co-Authors: David A. Eads, Dean E Biggins, Travis M Livieri, Joshua J. MillspaughAbstract:Insight into the spatial ecology of predators might help biologists to design wildlife reserves that maximize conservation success. We investigated the spatial ecology of endangered black-footed ferrets Mustela nigripes during the post-breeding seasons (June–October) of 2007 and 2008 on a 452-ha colony of black-tailed prairie dogs Cynomys ludovicianus in South Dakota, USA. Ferrets of both sexes frequently used areas with an abundance of active openings to prairie dog burrows, suggesting a positive response to refuge and prey. Densities of active burrow openings were similar in areas of same-sex overlap and areas of exclusive space use, which might suggest limited defense of resources by ferrets. However, this result could be expected in our study because much of the study colony contained high densities of active burrow openings. Same-sex home ranges overlapped in area, but the intensity of space use overlap was low. For male ferrets with overlapping home ranges, both males tended to spend low amounts of ...
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FINE-SCALE HABITAT USE OF REINTRODUCED BLACK-FOOTED FERRETS ON PRAIRIE DOG COLONIES IN NEW MEXICO
Western North American Naturalist, 2012Co-Authors: Jennifer G. Chipault, Dean E Biggins, James K. Detling, Dustin H. Long, Robin M. ReichAbstract:ABSTRACT. Black-footed ferrets (Mustela nigripes) are among the most endangered animals in North America. Reintroductions of captive-born ferrets onto prairie dog (Cynomys spp.) colonies are crucial to the conservation of the species. In September 2007, captive-born ferrets were released on a black-tailed prairie dog (Cynomys ludovicianus) colony at the Vermejo Park Ranch, New Mexico. Ferret kits experimentally released in areas of comparatively low and high prairie dog burrow densities were located via spotlight surveys. Some maturing ferret kits were subsequently translocated to areas of low and high burrow densities on nearby prairie dog colonies. For 2 months, fine-scale habitat use was quantified by mapping all burrow openings within a 30-m radius of each ferret location. Spatial statistics accounted for autocorrelation in the burrow densities in areas used by ferrets. It was hypothesized that ferrets would select areas of high burrow densities within colonies; however, burrow densities in areas used...
Elizabeth S Williams - One of the best experts on this subject based on the ideXlab platform.
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epidemiology of neoplasia in captive black footed ferrets Mustela nigripes 1986 1996
Journal of Zoo and Wildlife Medicine, 2009Co-Authors: Stephane Lair, Ian K Barker, Kay G Mehren, Elizabeth S WilliamsAbstract:Abstract The epidemiology of neoplastic disease was studied retrospectively in the captive population of black-footed ferrets (Mustela nigripes). Postmortem reports were reviewed and archived tissues examined from 184 of the 227 adult (>1 yr old) black-footed ferrets that died from the beginning of the current captive propagation program in late 1985 to the end of 1996. A total of 185 neoplasms, of 28 distinct phenotypes, were seen in 102 (55.4%) of these ferrets. There was more than one tumor type present in 51 ferrets. Tumors of the apocrine glands (28.3%), renal tubular neoplasms (20.7%), and biliary cystadenoma or carcinoma (20.1%) were the most common neoplasms. The probability of developing most types of neoplasms increased with age. Neoplasms of the apocrine glands were more common in males and may be hormonally influenced. The unusually high prevalence of biliary cystadenocarcinoma may be secondary to the common occurrence of intrahepatic biliary cysts in this population. Although neoplasia is an ...
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EPIDEMIOLOGY OF NEOPLASIA IN CAPTIVE BLACK-FOOTED FERRETS (Mustela nigripes), 1986–1996
Journal of Zoo and Wildlife Medicine, 2009Co-Authors: Stephane Lair, Ian K Barker, Kay G Mehren, Elizabeth S WilliamsAbstract:Abstract The epidemiology of neoplastic disease was studied retrospectively in the captive population of black-footed ferrets (Mustela nigripes). Postmortem reports were reviewed and archived tissues examined from 184 of the 227 adult (>1 yr old) black-footed ferrets that died from the beginning of the current captive propagation program in late 1985 to the end of 1996. A total of 185 neoplasms, of 28 distinct phenotypes, were seen in 102 (55.4%) of these ferrets. There was more than one tumor type present in 51 ferrets. Tumors of the apocrine glands (28.3%), renal tubular neoplasms (20.7%), and biliary cystadenoma or carcinoma (20.1%) were the most common neoplasms. The probability of developing most types of neoplasms increased with age. Neoplasms of the apocrine glands were more common in males and may be hormonally influenced. The unusually high prevalence of biliary cystadenocarcinoma may be secondary to the common occurrence of intrahepatic biliary cysts in this population. Although neoplasia is an ...
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renal tubular cell neoplasms in black footed ferrets Mustela nigripes 38 cases
Veterinary Pathology, 2006Co-Authors: S Lair, Kay G Mehren, Ian K Barker, Elizabeth S WilliamsAbstract:Thirty-eight cases of renal tubular cell neoplasms were diagnosed in 184 captive, adult (.1-year-old), black-footed ferrets (Mustela nigripes) examined from 1985 to 1996. This prevalence (20.7%) is one of the highest reported for this neoplasm in a population of animals. These tumors rarely metastasized (1/38), and usually were incidental postmortem findings, associated clinical disease being present in only 3 (8%) of the 38 cases. The prevalence of renal tubular cell neoplasms found at postmortem examination increased linearly with age, up to 67% in ferrets .8 years old. Both males (prevalence 5 19%) and females (prevalence 5 24%) were affected. Multiple renal tumors were common, and seven ferrets (18.4% of affected animals) had bilateral tumors. The cause of this neoplastic syndrome could not be determined. Since most of the animals affected by this condition were in their postreproductive years of life, the impact of this neoplastic syndrome on the captive propagation of this species is negligible.
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toxoplasma gondii infections in captive black footed ferrets Mustela nigripes 1992 1998 clinical signs serology pathology and prevention
Journal of Wildlife Diseases, 2003Co-Authors: Roy Burns, Elizabeth S Williams, Donal Otoole, J P DubeyAbstract:An epizootic of toxoplasmosis occurred among 22 adult and 30 kit black-footed ferrets (Mustela nigripes) maintained under quarantine conditions at the Louisville Zoological Garden (Louisville, Kentucky, USA) in June, 1992. Black-footed ferrets appear to be highly susceptible to acute and chronic toxoplasmosis. Clinical signs were observed in 19 adults and six kits and included anorexia, lethargy, corneal edema, and ataxia. Two adults and six kits died with acute disease. High antibody titers to Toxoplasma gondii were detected by latex agglutination and modified agglutination assay in 10 black-footed ferrets. One adult and six kits that died with acute clinical signs were necropsied and T. gondii-like organisms were found microscopically in multiple organs. Diagnosis of toxoplasmosis was confirmed by immunohistochemical staining with anti-T. gondii antibodies and by ultrastructural examination. Although the source of T. gondii for black-footed ferrets was not identified, frozen uncooked rabbit was the most...
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TOXOPLASMA GONDII INFECTIONS IN CAPTIVE BLACK-FOOTED FERRETS (Mustela nigripes), 1992–1998: CLINICAL SIGNS, SEROLOGY, PATHOLOGY, AND PREVENTION
Journal of Wildlife Diseases, 2003Co-Authors: Roy Burns, Elizabeth S Williams, Donal O’toole, J P DubeyAbstract:An epizootic of toxoplasmosis occurred among 22 adult and 30 kit black-footed ferrets (Mustela nigripes) maintained under quarantine conditions at the Louisville Zoological Garden (Louisville, Kentucky, USA) in June, 1992. Black-footed ferrets appear to be highly susceptible to acute and chronic toxoplasmosis. Clinical signs were observed in 19 adults and six kits and included anorexia, lethargy, corneal edema, and ataxia. Two adults and six kits died with acute disease. High antibody titers to Toxoplasma gondii were detected by latex agglutination and modified agglutination assay in 10 black-footed ferrets. One adult and six kits that died with acute clinical signs were necropsied and T. gondii-like organisms were found microscopically in multiple organs. Diagnosis of toxoplasmosis was confirmed by immunohistochemical staining with anti-T. gondii antibodies and by ultrastructural examination. Although the source of T. gondii for black-footed ferrets was not identified, frozen uncooked rabbit was the most...
Stanley H Anderson - One of the best experts on this subject based on the ideXlab platform.
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influence of prerelease experience on reintroduced black footed ferrets Mustela nigripes
Biological Conservation, 1999Co-Authors: Dean E Biggins, Astrid Vargas, Jerry L Godbey, Stanley H AndersonAbstract:Captive breeding is increasingly being used to create supplies of endangered animals for release into natural habitats, but rearing strategies vary and debates arise over which methods are most eAcient. We assessed postrelease behaviors and survival of three groups of black-footed ferrets, each with diAerent prerelease experience. Eighteen ferret kits60 days of age were moved with their dams from cages to 80-m 2 outdoor pens with prairie dog burrows. These animals were compared to animals reared in standard cages (na 72), some of which were given experience killing prairie dogs (na 32). Ferrets were released onto white-tailed prairie dog (Cynomys leucurus) colonies in Wyoming, USA, in fall, 1992. Radio-tagged cage-reared ferrets made longer nightly moves and dispersed further from release sites than their pen-reared counterparts. The band return rate was 4-fold higher for pen-reared animals than for cage-reared animals during surveys conducted about 1 month after release. We recommend routine use of quasinatural outdoor pens for prerelease conditioning of black-footed ferrets. Published by Elsevier Science Ltd.
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effects of experience and cage enrichment on predatory skills of black footed ferrets Mustela nigripes
Journal of Mammalogy, 1999Co-Authors: Astrid Vargas, Stanley H AndersonAbstract:We studied ontogeny of predatory skills of growing black-footed ferrets ( Mustela nigripes ) raised under different captive conditions. To test effects of maturation, experience, and cage enrichment on predatory behavior, we exposed 70 juvenile black-footed ferrets to different numbers of live hamsters ( Mesocricetus auratus ) throughout development. Both maturation and experience increased the likelihood of a black-footed ferret making a successful kill. Black-footed ferrets exposed to greater environmental complexity (enriched cage, including encouragement of food-searching behaviors) also were more likely to kill than ferrets raised in a deprived environment. Behavioral studies of captive-raised black-footed ferrets can help refine current breeding techniques and ultimately enhance efforts to recover this endangered carnivore.
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Ontogeny of black-footed ferret predatory behavior towards prairie dogs
Canadian Journal of Zoology, 1998Co-Authors: Astrid Vargas, Stanley H AndersonAbstract:To study the effects of environmental upbringing and predation experience on black-footed ferret (Mustela nigripes) predatory skills towards prairie dogs, we compared killing efficiency and behaviors of 32 black-footed ferret kits (from 24 different litters). Four treatment groups were established: group 1 (n = 8), kits raised in indoor cages and never exposed to live prey; group 2 (n = 8), kits raised in indoor cages and fed live hamsters twice a week beginning at 8 weeks of age; group 3 (n = 8), kits raised in indoor cages, fed live hamsters, and exposed to live prairie dogs in family trials once per week; and group 4, kits raised in outdoor enclosures with ad libitum access to live prairie dogs in natural burrows. Juvenile black-footed ferrets raised with exposure to live hamsters were more successful at killing prairie dogs than kits devoid of any predation experience. Previous experience with prairie dogs (in both indoor cages and outdoor pens) significantly increased predation efficiency. Witnessing...
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Black-footed ferret (Mustela nigripes) behavioral development: aboveground activity and juvenile play
Journal of Ethology, 1998Co-Authors: Astrid Vargas, Stanley H AndersonAbstract:We studied the behavioral development of black-footed ferrets ( Mustela nigripes ) from 6 to 16 post-natal weeks. At 6 weeks of age, kits are still lactating and depend on their mother for survival, while at 16 weeks, ferret young start achieving independence from their mother and littermates. Behavioral observations were obtained by placing videomonitors in the litters’ cages, nest boxes and in outdoor naturalistic enclosures. Captive-raised black-footed ferrets displayed nocturnal activity patterns, although they tended to appear aboveground at certain daytime hours presumably influenced by the established feeding and cleaning regimes. Growing ferrets began emerging aboveground at approximately 7 post-natal weeks and diel activity steadily increased as kits matured. The most manifest behavioral changes (appearance of new motor patterns, increase in aboveground play and in neck-biting behaviors) occurred from post-natal week 8 to week 12. This coincides with the period of maximum growth for ferrets and with a sensitive phase for the development of food preferences in this species. Changes from the 12 to the 16 post-natal weeks involved an increase in aboveground activity, including a higher frequency of scent-marking behaviors. Information provided in this study has important implications for enhancing the captive management of this endangered carnivore.
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Effects of diet on captive black‐footed ferret (Mustela nigripes) food preference
Zoo Biology, 1996Co-Authors: Astrid Vargas, Stanley H AndersonAbstract:Black-footed ferrets (Mustela nigripes) are both habitat and prey specialists that depend on prairie dogs (Cynomys spp.) for food and utilize prairie dog burrows for refuge. In this study we investigated the effects of captive diet during early development on adult black-footed ferret food preferences. To test the hypothesis that early diet affects the food preferences of adult black-footed ferrets, we exposed 22 kits (divided into three experimental groups) to different quantities of prairie dog in the diet: no prairie dog, prairie dog three times per week, and prairie dog daily during the assumed sensitive period for olfactory imprinting, i.e., between 60–90 postnatal days. At age 5 months, kits were individually tested in a food choice cafeteria trial. Results indicated that higher amounts of prairie dog in the ferrets' early diet led to a higher preference for this food item when ferrets reached adulthood. These results have important implications for black-footed ferret recovery and have been considered in the reintroduction protocol. © 1996 Wiley-Liss, Inc.
Samantha M. Wisely - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the genetic management of the endangered black‐footed ferret (Mustela nigripes)
Zoo Biology, 2020Co-Authors: Samantha M. Wisely, David B Mcdonald, S W BuskirkAbstract:Empirical support for the genetic management strategies employed by captive breeding and reintroduction programs is scarce. We evaluated the genetic management plan for the highly endangered black-footed ferret (Mustela nigripes) developed by the American Zoo and Aquarium Associations (AZA) as a part of the species survival plan (SSP). We contrasted data collected from five microsatellite loci to predictions from a pedigree-based kinship matrix analysis of the captive black-footed ferret population. We compared genetic diversity among captive populations managed for continued captive breeding or reintroduction, and among wild-born individuals from two reintroduced populations. Microsatellite data gave an accurate but only moderately precise estimate of heterozygosity. Genetic diversity was similar in captive populations maintained for breeding and release, and it appears that the recovery program will achieve its goal of maintaining 80% of the genetic diversity of the founder population over 25 years. Wild-born individuals from reintroduced populations maintained genetic diversity and avoided close inbreeding. We detected small but measurable genetic differentiation between the reintroduced populations. The model of random mating predicted only slightly lower levels of heterozygosity retention compared to the SSP strategy. The random mating strategy may be a viable alternative for managing large, stable, captive populations such as that of the black-footed ferret. Zoo Biol 22:287–298, 2003. © 2003 Wiley-Liss, Inc.
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Genotypic and phenotypic consequences of reintroduction history in the black-footed ferret (Mustela nigripes)
Conservation Genetics, 2008Co-Authors: Samantha M. Wisely, Travis M Livieri, Rachel M Santymire, Sara A. Mueting, Jogayle HowardAbstract:Population augmentation with translocated individuals has been shown to alleviate the effects of bottlenecks and drift. The first step to determine whether restoration for genetic considerations is warranted is to genetically monitor reintroduced populations and compare results to those from the source. To assess the need for genetic restoration, we evaluated genetic diversity and structure of reintroduced ( n = 3) and captive populations of the endangered black-footed ferret ( Mustela nigripes ). We measured genotypic changes among populations using seven microsatellite markers and compared phenotypic changes with eight morphometric characters. Results indicated that for the population which rapidly grew post-reintroduction, genetic diversity was equivalent to the captive, source population. When growth languished, only the population that was augmented yearly maintained diversity. Without augmentation, allelic diversity declined precipitously and phenotypic changes were apparent. Ferrets from the genetically depaupertate population had smaller limbs and smaller overall body size than ferrets from the two populations with greater diversity. Population divergence ( F _ST = 0.10 ± 0.01) was surprisingly high given the common source of populations. Thus, it appears that 5–10 years of isolation resulted in both genotypic divergence and phenotypic changes to populations. We recommend translocation of 30–40 captive individuals per annum to reintroduction sites which have not become established quickly. This approach will maximize the retention of genetic diversity, yet maintain the beneficial effects of local adaptation without being swamped by immigration.
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pleistocene refugia and holocene expansion of a grassland dependent species the black footed ferret Mustela nigripes
Journal of Mammalogy, 2008Co-Authors: Samantha M. Wisely, Mark J Statham, Robert C FleischerAbstract:Abstract Climate change during the late Quaternary has been implicated as the cause of both massive range shifts and extinction events. We combined molecular marker data and previously published fossil data to reconstruct the late Quaternary history of a grassland-dependent species, the black-footed ferret (Mustela nigripes), and to determine whether populations from Pleistocene refugia in the Columbia Basin, eastern Beringia, and Great Plains persisted into the Holocene and Recent eras. Using DNA extracted from 97 museum specimens of extirpated populations, we amplified 309 bp of the mtDNA control region, and 8 microsatellite markers from the nuclear genome. Overall haplotype diversity from 309 base pairs (bp) of mitochondrial DNA (mtDNA) control region was low (5 haplotypes, nucleotide diversity = 0.001 ± 0.001 SD) and was contained within a single phylogenetic clade. The star phylogeny and unimodal mismatch distribution indicated that a rapid range expansion from a single Pleistocene refugium occurred....
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MORTALITY OF CAPTIVE BLACK-FOOTED FERRETS (Mustela nigripes) AT SMITHSONIAN'S NATIONAL ZOOLOGICAL PARK, 1989–2004
Journal of Zoo and Wildlife Medicine, 2007Co-Authors: Ellen Bronson, R. Mitchell Bush, Tabitha Viner, Suzan Murray, Samantha M. Wisely, Sharon L. DeemAbstract:Abstract Black-footed ferret (Mustela nigripes) mortality was investigated retrospectively based on the pathology records of 107 captive animals held at Smithsonian's National Zoological Park from 1989 to 2004. The majority of deaths in neonates were due to cannibalism (n = 42; 64.6%) and maternal trauma (n = 11; 16.9%); both of these causes of mortality decreased during the study period. Prior to 2001, juvenile mortality was most often caused by gastrointestinal disease (n = 11; 52.4%), including coccidiosis, salmonellosis, and clostridium infection. In 2001, improvements in husbandry, hygiene, and medical treatment led to decreases in juvenile mortality associated with gastrointestinal disease. The most common causes of death in adult ferrets were renal or neoplastic disease. The etiology of the high prevalence of renal disease in the last 4 yr of the study is unknown; it was not associated with increasing age or inbreeding. Improved hygiene and vigilant monitoring for signs of gastrointestinal and rena...
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mortality of captive black footed ferrets Mustela nigripes at smithsonian s national zoological park 1989 2004
Journal of Zoo and Wildlife Medicine, 2007Co-Authors: Ellen Bronson, Tabitha Viner, Suzan Murray, Samantha M. Wisely, Mitchell R Bush, Sharon L. DeemAbstract:Abstract Black-footed ferret (Mustela nigripes) mortality was investigated retrospectively based on the pathology records of 107 captive animals held at Smithsonian's National Zoological Park from 1989 to 2004. The majority of deaths in neonates were due to cannibalism (n = 42; 64.6%) and maternal trauma (n = 11; 16.9%); both of these causes of mortality decreased during the study period. Prior to 2001, juvenile mortality was most often caused by gastrointestinal disease (n = 11; 52.4%), including coccidiosis, salmonellosis, and clostridium infection. In 2001, improvements in husbandry, hygiene, and medical treatment led to decreases in juvenile mortality associated with gastrointestinal disease. The most common causes of death in adult ferrets were renal or neoplastic disease. The etiology of the high prevalence of renal disease in the last 4 yr of the study is unknown; it was not associated with increasing age or inbreeding. Improved hygiene and vigilant monitoring for signs of gastrointestinal and rena...
Jogayle Howard - One of the best experts on this subject based on the ideXlab platform.
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Reproductive inefficiency in male black‐footed ferrets (Mustela nigripes)
Zoo Biology, 2020Co-Authors: K N Wolf, David E Wildt, Paul E Marinari, Mary Ann Ottinger, A. Vargas, Jogayle HowardAbstract:The black-footed ferret (Mustela nigripes), once considered extinct, has benefited from captive breeding and subsequent reintroduction into native habitat. A high proportion of females (>90%) exhibit estrus in captivity during the spring breeding season. However, many males considered to be prime-breeding age (1–3 years old) fail to sire offspring. Breeding records in 1995 revealed that 40 of 73 males (55%) managed under the Black-Footed Ferret Species Survival Plan did not reproduce, despite being provided opportunity. The present study was conducted to determine the incidence and etiology of male reproductive failure in 1996 and 1997. In 1996, 38 of 69 (55%) 1- to 3-year-old males failed to sire offspring. Likewise, 35 of 60 (58%) males did not reproduce in 1997. Overall, 21% of adult males failed to sire young in three consecutive breeding seasons (1995–1997). Electroejaculate traits (ejaculate volume, sperm concentration, motility, morphology, and acrosomal integrity) from 29 proven breeder males were not different (P > 0.05) from those of 23 males that did not sire young (nonproven breeders). However, six categories of reproductive failure were identified for the 73 prime-breeding age, nonproven males: 1) underdeveloped testes (22%); 2) improper breeding position with the female (25%); 3) excessive aggression toward estrous females (9%); 4) copulation with no sperm detected at postcoital lavage (19%); 5) copulation with sperm in the vaginal lavage but no resulting pregnancy (18%); and 6) copulation with no vaginal lavage performed and no resulting pregnancy (7%). These data indicate that combined behavioral and physiologic factors, but not overall sperm quality, influence reproductive performance in male black-footed ferrets managed in captivity. Zoo Biol 19:517–528, 2000. © 2000 Wiley-Liss, Inc.
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Approaches and efficacy of artificial insemination in felids and mustelids
Theriogenology, 2008Co-Authors: Jogayle Howard, David E WildtAbstract:Two of the most diverse and species-rich families in the order Carnivora (containing 280 species) include Felidae (cats) and Mustelidae (commonly called weasels). According to a current taxonomic classification system, the family Felidae consists of 41 felid species, most of which are listed as threatened or endangered with extinction [1]. The family Mustelidae consists of 59 species (including weasels, ferrets, minks, badgers, otters, wolverines), with the North American black-footed ferret (Mustela nigripes) being the most endangered [1]. Ex situ breeding programs exist for many of these rare carnivores, and one of the highest priorities is the retention of existing gene diversity to ensure species integrity, health and reproduction. Tools associated with ‘assisted reproduction’ offer multiple advantages for species propagated under the auspices of an organized genetic management plan (e.g., the Species Survival Plan or SSP#; Table 1) [2,3]. Because cooperating institutions (usually zoos) breed animals on the basis of the genetic value of individuals and computerized calculations of
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Genotypic and phenotypic consequences of reintroduction history in the black-footed ferret (Mustela nigripes)
Conservation Genetics, 2008Co-Authors: Samantha M. Wisely, Travis M Livieri, Rachel M Santymire, Sara A. Mueting, Jogayle HowardAbstract:Population augmentation with translocated individuals has been shown to alleviate the effects of bottlenecks and drift. The first step to determine whether restoration for genetic considerations is warranted is to genetically monitor reintroduced populations and compare results to those from the source. To assess the need for genetic restoration, we evaluated genetic diversity and structure of reintroduced ( n = 3) and captive populations of the endangered black-footed ferret ( Mustela nigripes ). We measured genotypic changes among populations using seven microsatellite markers and compared phenotypic changes with eight morphometric characters. Results indicated that for the population which rapidly grew post-reintroduction, genetic diversity was equivalent to the captive, source population. When growth languished, only the population that was augmented yearly maintained diversity. Without augmentation, allelic diversity declined precipitously and phenotypic changes were apparent. Ferrets from the genetically depaupertate population had smaller limbs and smaller overall body size than ferrets from the two populations with greater diversity. Population divergence ( F _ST = 0.10 ± 0.01) was surprisingly high given the common source of populations. Thus, it appears that 5–10 years of isolation resulted in both genotypic divergence and phenotypic changes to populations. We recommend translocation of 30–40 captive individuals per annum to reintroduction sites which have not become established quickly. This approach will maximize the retention of genetic diversity, yet maintain the beneficial effects of local adaptation without being swamped by immigration.
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slow cooling prevents cold induced damage to sperm motility and acrosomal integrity in the black footed ferret Mustela nigripes
Reproduction Fertility and Development, 2007Co-Authors: David E Wildt, Paul E Marinari, Rachel M Santymire, J S Kreeger, Jogayle HowardAbstract:The endangered black-footed ferret (Mustela nigripes) has benefited from artificial insemination; however, improved sperm cryopreservation protocols are still needed. The present study focused on identifying factors influencing gamete survival during processing before cryopreservation, including: (1) the presence or absence of seminal plasma; (2) temperature (25°C v. 37°C); (3) type of medium (Ham’s F10 medium v. TEST yolk buffer [TYB]); (4) cooling rate (slow, rapid and ultra-rapid); and (5) the presence or absence of glycerol. Seminal plasma did not compromise (P > 0.05) sperm motility or acrosomal integrity. Sperm motility traits were maintained longer (P 0.05) acrosomal integrity. Overall, TYB maintained optimal (P 0.05), indicating that 4% glycerol was non-toxic to ferret sperm; however, glycerol failed to ameliorate the detrimental effects of either rapid or ultra-rapid cooling. The results of the present study demonstrate that the damage observed to black-footed ferret spermatozoa is derived largely from the rate of cooling.
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environment influences morphology and development for in situ and ex situ populations of the black footed ferret Mustela nigripes
Animal Conservation, 2005Co-Authors: Samantha M. Wisely, David E Wildt, Paul E Marinari, Travis M Livieri, Rachel M Santymire, J S Kreeger, Jogayle HowardAbstract:For selected species, conservation breeding has become integrated into recovery plans, most often through the production of offspring for reintroduction into nature. As these programs increase in size and scope, it is imperative that conservation managers retain the biological integrity of the species. This study investigated the causes of morphological changes that are known to occur in black-footed ferrets (Mustela nigripes) maintained ex situ. In a previous study, ferrets maintained in captivity were 5–10% smaller in body size than pre-captive, in situ animals. In the present study, the authors compared nine morphological characters among ex situ animals and their in situ descendants. Within the ex situ population, cage types were compared to determine whether housing influenced morphometry. Black-footed ferrets born to reintroduced individuals quickly returned to their pre-captive size suggesting that a diminutive morphology ex situ did not have a genetic basis. Furthermore, cage type affected overall body size and shape; ulnas and tibias were as much as 9% shorter for ex situ animals. The authors hypothesise that small cage size and environmental homogeneity inhibit the mechanical stimuli necessary for long bone development. These findings have ramifications for ex situ managers who need to create artificial captive settings that promote natural physical development. In the absence of such an environment, ‘unnatural’ morphologies can result that may contribute to poor fitness or perhaps even domestication.
