SELECTED INSTANCES OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS SHEDDING IN TRUNK SECRETIONS BY AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN COMPARISON TO SHEDDING BY ASIAN ELEPHANTS (ELEPHAS MAXIMUS)

This study examined the viral shedding kinetics of elephant endotheliotropic herpesvirus (EEHV) in African elephants (Loxodonta africana) compared to viral shedding behavior in Asian elephants (Elephas maximus). Little is known about the transmission dynamics and epidemiology of this disease in African elephants. In light of recent clinical cases and mortalities, this paper aims to identify trends in viral biology. Trunk wash samples were collected from 22 African elephants from four North American zoological institutions that had recently experienced herd viremias or translocations. Processing of these samples included DNA extraction followed by qPCR to quantitate viral DNA load. The results were then compared with available literature that chronicled similar cases in Asian and African elephants. Minimal EEHV shedding was detected in response to varied herd translocations. Increased shedding was recorded in herds in which an elephant experienced an EEHV viremia when compared to baseline shedding. These index infections were followed by subsequent viremias in other elephants, although it is not known if these were recrudescence, transient controlled viremias, and/or primary infections via transmission to other elephants. When compared to historically published data, it was observed that EEHV3 cases in African elephants and EEHV1A cases in Asian elephants had consistently higher levels of viral DNA in the blood than were shed in trunk secretions, a fact that is seemingly inconsistent with such severe cases of disease and the high mortality rates associated with those respective types. The findings produced in this study highlight the need for more routine monitoring of viral shedding in African elephant herds to elucidate possible EEHV transmission and recrudescence factors for ex situ population management.

Development of genetic markers for reproductive management of toucans

Retention of genetic diversity in successive generations is key to successful ex situ programs and will become increasingly important to restore wild populations of threatened animals. When animal genealogy is partly unknown or gaps exist in studbook records, the application of molecular resources facilitates informed breeding. Here, we apply molecular resources to an ex situ breeding population of toucans (Ramphastidae), a bird family zoos commonly maintain. Toucans face population declines from illegal poaching and habitat degradation. We developed novel microsatellite markers using blood samples from 15 Keel-billed Toucans (Ramphastos sulfuratus Lesson 1830). Parentage of two individuals was known a priori, but possible sibship among 13 putative founders-including the parents-was unknown. We compared available avian heterologous and novel microsatellite markers to recover known relationships and reconstruct sibship. Eight of 61 heterologous markers amplified consistently and were polymorphic, but less so than the 18 novel markers. Known sibship (and three sibling pairs whose relatedness was unknown a priori) and paternity-though not maternity except in one case-were well-recovered using both likelihood and pairwise relatedness methods, when incorporating novel but not heterologous markers. Zoo researchers seeking microsatellite primer sets for their breeding toucan populations will likely benefit from our heterologous markers, which can be leveraged both to assess relatedness and select breeding pairs. We recommend that zoo biologists rely on species-specific primers and not optimize heterologous primers for toucan species without molecular resources. We conclude with a brief discussion of modern genotyping methods of interest to zoo researchers.

Genetic diversity and relatedness in captive collared peccaries Dicotyles tajacu (Linnaeus, 1758) (Cetartiodactyla: Tayassuidae) estimated by microsatellite genotyping using high-throughput sequencing: Implications for their conservation and reintroduction

The global population of Dicotyles tajacu (Linnaeus, 1758) (Cetartiodactyla: Tayassuidae), commonly known as the collared peccary and distributed in the Neotropics, is currently in decline due to anthropogenic pressures. In this study, five microsatellite loci were used to genetically characterize a group of 20 captive-born collared peccaries intended for reintroduction. This study aimed to evaluate the genetic diversity and relatedness of captive individuals using microsatellite markers. The genetic data generated were used to evaluate the viability of the reintroduction and to propose measures for the management and conservation of this species. In this study, we found relatively high genetic diversity indices, indicating that the group was genetically diverse. Inbreeding coefficients with negative values were observed, indicating an excess of alleles in heterozygosis and an absence of inbreeding. One locus showed deviation from Hardy-Weinberg equilibrium, which may have been caused by the mixing of individuals from different origins. Relatedness analysis indicated that some individuals were highly related, with coefficients indicating they may be first-degree relatives. Our findings indicate that the studied group has enough genetic diversity to be released into nature, but the high individual relatedness found would require the adoption of strategies after the release of animals in the wild to ensure their persistence.

Wild origins and mitochondrial genetic diversity of Angolan Colobus monkeys (Colobus angolensis) in AZA-accredited zoos and its implications for ex situ population management

Across zoo's accredited by the Association of Zoos and Aquariums (AZA), species are typically managed as a single population to retain 90% of the founding members' gene diversity. Often, little is known about the specific geographic origins of the founders or how representative the ex situ population's genetic diversity is of the wild population. This study uses mitochondrial DNA (mtDNA) sequencing to investigate haplotype diversity and geographic female founder origin of the AZA-managed Angolan colobus (Colobus angolensis) monkey population. We obtained fecal samples from individuals closely related to founder animals at five zoos and found four haplotypes among 23 individuals. Analyzed together with wild C. angolensis haplotypes, we found two haplotypes identical to those found in Tanzanian populations: one haplotype, possessed by 13 individuals (descended from three founders), matched an East Usambara Mountains haplotype, while the other, possessed by seven individuals (from four founders), matched a haplotype found in both the South Pare Mountains and Rufiji River. Two haplotypes were not detected in wild populations but were closely related to haplotypes found in the Rufiji River (one individual descended from one founder) and Shimoni, Kenya (two individuals descended from one founder) populations, suggesting nearby origins. Thus, the AZA-managed population of Angolan colobus likely originated from several localities, but all have mtDNA lineages associated with the subspecies C. a. palliatus, a Vulnerable subspecies. Examining founders' mtDNA haplotypes may be a useful addition to the zoo population management toolkit to help improve breeding recommendations by identifying individuals with rare haplotypes and revealing likely kinship among founders.

Losing the forest for the tree? On the wisdom of subpopulation management

Animal habitats are changing around the world in many ways, presenting challenges to the survival of species. Zoo animal populations are also challenged by small population sizes and limited genetic diversity. Some ex situ populations are managed as subpopulations based on presumed subspecies or geographic locality and related concerns over genetic purity or taxonomic integrity. However, these decisions can accelerate the loss of genetic diversity and increase the likelihood of population extinction. Here I challenge the wisdom of subpopulation management, pointing out significant concerns in the literature with delineation of species, subspecies, and evolutionarily significant units. I also review literature demonstrating the value of gene flow for preserving adaptive potential, the often-misunderstood role of hybridization in evolution, and the likely overstated concerns about outbreeding depression, and preservation of local adaptations. I argue that the most effective way to manage animal populations for the long term be they in human care, in the wild, or if a captive population is being managed for reintroduction, is to manage for maximum genetic diversity rather than managing subpopulations focusing on taxonomic integrity, genetic purity, or geographic locale because selection in the future, rather than the past, will determine what genotypes and phenotypes are the most fit. Several case studies are presented to challenge the wisdom of subpopulation management and stimulate thinking about the preservation of genomes rather than species, subspecies, or lineages because those units evolved in habitats that are likely very different from those habitats today and in the future.

Institutional networks in cooperative population management: Exploring patterns in transfer fulfillment

Long-term sustainability of ex-situ animal populations is important for zoos and aquariums, but challenging due to inconsistent compliance with Breeding and Transfer Plans. Transfer recommendations are key to promoting the sustainability of ex-situ animal populations by ensuring cohesive populations, genetic diversity, and demographic stability, but factors affecting their fulfillment are poorly understood. We used a network analysis framework to analyze data compiled from PMCTrack from 2011 to 2019 for three taxonomic classes (mammals, birds, and reptiles/amphibians) within the Association of Zoos and Aquariums to assess factors affecting transfer recommendation fulfillment. Of 2505 compiled transfer recommendations spanning 330 Species Survival Plan® (SSP) Programs and 156 institutions, 1628 (65%) of them were fulfilled. Transfers were most likely to be fulfilled between institutions in close proximity with an established relationship. Annual operating budget, SSP Coordinator experience, number of staff, and diversity of Taxonomic Advisory Groups in which an institution participates also influenced transfer recommendations and/or fulfillment, but effects varied with taxonomic class. Our results suggest that current practices of focusing on transfers between institutions in close proximity are working to maximize transfer success and that institutions with larger budgets and some degree of taxonomic specialization play important roles in promoting success. Success could be further enhanced by building reciprocal transfer relationships and encouraging further development of relationships between smaller institutions and larger ones. These results emphasize the utility of examining animal transfers using a network approach, which accounts for attributes of both sending and receiving institutions, describing novel patterns otherwise left undetected.

How was genetic diversity transferred with translocations from ex situ to in situ? A case study of the European mink translocation to Hiiumaa Island in Estonia

The European mink (Mustela lutreola) is one of the most threatened small carnivores, listed as Critically Endangered on the IUCN Red List. Tallinn Zoo started a conservation breeding operation in 1980, which in 1992 was shaped into the European mink EEP Program to maintain a demographically and genetically healthy population in captivity. Since 2000, mink have been translocated on a yearly basis from the breeding facility in the zoo to Hiiumaa Island (Estonia) until the formation of the wild island population in 2016. Maintaining a healthy genetic structure in a captive population was a priority, so genetically the least valuable animals, according to calculations made by a population management program, were used for translocation. This study aims to assess the amount of genetic diversity passed from an ex situ population on to the island population. Comparisons of the genetic diversity were made by mitochondrial, microsatellite and nuclear markers. In addition, our results were combined with the pedigree data from the European mink EEP Studbook to further evaluate the flow of genetic diversity from the founder population to the established wild population. According to the findings, the island population's allelic richness was comparable to that of the founder population, and no evidence was found that its genetic structure had diverged from that of the founder population. It seems that the formation of the island population has been a gradual process of no more than the last seven yearly translocations.

Backcrossing as a species restoration technique

An investigation was conducted on the phenotypic results of mouse hybridization and seven generations of backcrossing, observing reciprocal F1 hybrids and backcrosses of Mus spretus and a laboratory strain of Mus domesticus C57BL/6J. F1 hybrids, backcrosses, and pure control specimens were measured for 6 body characteristics, 4 pelage coloration characteristics, 14 behaviors, and reproduction as reflected in litter size. Backcrossing was pursued for seven generations to FBC7 (i.e., "Backcross 7" or seven generations from commencement of backcrossing from an F1 hybrid female) where species restoration is mathematically calculated to be at 99.7%. Except for a minority of FBC7 M. spretus specimens failing to conform completely to one pelage characteristic, FBC7 specimens were indistinguishable from controls both subjectively and in all areas of measurement. The M. spretus backcross line was followed generation by generation and was largely conforming to controls by FBC4 at latest. The same effect was observed in the reciprocal M. domesticus backcross line. Fertility was negatively affected in F1 hybrids but restored or improved in backcross generations. Discussion is offered on hybridization and backcrossing as it occurs in nature and how it has been used or could be used as an additional ex situ tool in wildlife conservation efforts. It is concluded that conservation-oriented backcrossing is a practical species/subspecies restoration technique and has the potential to make genetic rescue feasible with minimal gene flow at the binomial level. Backcrossing is most applicable in closely monitored ex situ settings (1) where only one sex remains of a given taxon; and (2) where inbreeding depression seriously threatens a remnant taxon's ability to recover, and the only gene flow option is from another distinct species.

Zoo animal manure as an overlooked reservoir of antibiotic resistance genes and multidrug-resistant bacteria

Animal fecal samples collected in the summer and winter from 11 herbivorous animals, including sable antelope (SA), long-tailed goral (LTG), and common eland (CE), at a public zoo were examined for the presence of antibiotic resistance genes (ARGs). Seven antibiotics, including meropenem and azithromycin, were used to isolate culturable multidrug-resistant (MDR) strains. The manures from three animals (SA, LTG, and CE) contained 10⁴-fold higher culturable MDR bacteria, including Chryseobacterium, Sphingobacterium, and Stenotrophomonas species, while fewer MDR bacteria were isolated from manure from water buffalo, rhinoceros, and elephant against all tested antibiotics. Three MDR bacteria-rich samples along with composite samples were further analyzed using nanopore-based technology. ARGs including lnu(C), tet(Q), and mef(A) were common and often associated with transposons in all tested samples, suggesting that transposons carrying ARGs may play an important role for the dissemination of ARGs in our tested animals. Although several copies of ARGs such as aph(3')-IIc, bla_L1, bla_IND-3, and tet(42) were found in the sequenced genomes of the nine MDR bacteria, the numbers and types of ARGs appeared to be less than expected in zoo animal manure, suggesting that MDR bacteria in the gut of the tested animals had intrinsic resistant phenotypes in the absence of ARGs.

Social network analysis and whole-genome sequencing to evaluate disease transmission in a large, dynamic population: A study of avian mycobacteriosis in zoo birds

This study combined a social network analysis and whole-genome sequencing (WGS) to test for general patterns of contagious spread of a mycobacterial infection for which pathways of disease acquisition are not well understood. Our population included 275 cases diagnosed with avian mycobacteriosis that were nested in a source population of 16,430 birds at San Diego Zoo Wildlife Alliance facilities from 1992 through mid-2014. Mycobacteria species were determined using conventional methods and whole genome sequencing (WGS). Mycobacterium avium avium (MAA) and Mycobacterium genavense were the most common species of mycobacteria identified and were present in different proportions across bird taxa. A social network for the birds was constructed from the source population to identify directly and indirectly connected cases during time periods relevant to disease transmission. Associations between network connectivity and genetic similarity of mycobacteria (as determined by clusters of genotypes separated by few single nucleotide polymorphisms, or SNPs) were then evaluated in observed and randomly generated network permutations. Findings showed that some genotypes clustered along pathways of bird connectivity, while others were dispersed throughout the network. The proportion of directly connected birds having a similar mycobacterial genotype was 0.36 and significant (p<0.05). This proportion was higher (0.58) and significant for MAA but not for M. genavense. Evaluations of SNP distributions also showed genotypes of MAA were more related in connected birds than expected by chance; however, no significant patterns of genetic relatedness were identified for M. genavense, although data were sparse. Integrating the WGS analysis of mycobacteria with a social network analysis of their host birds revealed significant genetic clustering along pathways of connectivity, namely for MAA. These findings are consistent with a contagious process occurring in some, but not all, case clusters.

Herpesvirus surveillance and discovery in zoo-housed ruminants

Gammaherpesvirus infections are ubiquitous in captive and free-ranging ruminants and are associated with a variety of clinical diseases ranging from subclinical or mild inflammatory syndromes to fatal diseases such as malignant catarrhal fever. Gammaherpesvirus infections have been fully characterized in only a few ruminant species, and the overall diversity, host range, and biologic effects of most are not known. This study investigated the presence and host distribution of gammaherpesviruses in ruminant species at two facilities, the San Diego Zoo and San Diego Zoo Safari Park. We tested antemortem (blood, nasal or oropharyngeal swabs) or postmortem (internal organs) samples from 715 healthy or diseased ruminants representing 96 species and subspecies, using a consensus-based herpesvirus PCR for a segment of the DNA polymerase (DPOL) gene. Among the 715 animals tested, 161 (22.5%) were PCR and sequencing positive for herpesvirus, while only 11 (6.83%) of the PCR positive animals showed clinical signs of malignant catarrhal fever. Forty-four DPOL genotypes were identified of which only 10 have been reported in GenBank. The data describe viral diversity within species and individuals, identify host ranges of potential new viruses, and address the proclivity and consequences of interspecies transmission during management practices in zoological parks. The discovery of new viruses with wide host ranges and presence of co-infection within individual animals also suggest that the evolutionary processes influencing Gammaherpesvirus diversity are more complex than previously recognized.

Serum Amyloid A Protein Concentration in Blood is Influenced by Genetic Differences in the Cheetah (Acinonyx jubatus)

Systemic amyloid A (AA) amyloidosis is a major cause of morbidity and mortality among captive cheetahs. The self-aggregating AA protein responsible for this disease is a byproduct of serum amyloid A (SAA) protein degradation. Transcriptional induction of the SAA1 gene is dependent on both C/EBPβ and NF-κB cis-acting elements within the promoter region. In cheetahs, 2 alleles exist for a single guanine nucleotide deletion in the putative NF-κB binding site. In this study, a novel genotyping assay was developed to screen for the alleles. The results show that the SAA1A (-97delG) allele is associated with decreased SAA protein concentrations in the serum of captive cheetahs (n = 58), suggesting genetic differences at this locus may be affecting AA amyloidosis prevalence. However, there was no significant difference in the frequency of the SAA1A (-97delG) allele between individuals confirmed AA amyloidosis positive versus AA amyloidosis negative at the time of necropsy (n = 48). Thus, even though there is evidence that having more copies of the SAA1A (-97delG) allele results in a potentially protective decrease in serum concentrations of SAA protein in captive cheetahs, genotype is not associated with this disease within the North American population. These results suggest that other factors are playing a more significant role in the pathogenesis of AA amyloidosis among captive cheetahs.

The genetic integrity of the ex situ population of the European wildcat (Felis silvestris silvestris) is seriously threatened by introgression from domestic cats (Felis silvestris catus)

Studies on the genetic diversity and relatedness of zoo populations are crucial for implementing successful breeding programmes. The European wildcat, Felis s. silvestris, is subject to intensive conservation measures, including captive breeding and reintroduction. We here present the first systematic genetic analysis of the captive population of Felis s. silvestris in comparison with a natural wild population. We used microsatellites and mtDNA sequencing to assess genetic diversity, structure and integrity of the ex situ population. Our results show that the ex situ population of the European wildcat is highly structured and that it has a higher genetic diversity than the studied wild population. Some genetic clusters matched the breeding lines of certain zoos or groups of zoos that often exchanged individuals. Two mitochondrial haplotype groups were detected in the in situ populations, one of which was closely related to the most common haplotype found in domestic cats, suggesting past introgression in the wild. Although native haplotypes were also found in the captive population, the majority (68%) of captive individuals shared a common mtDNA haplotype with the domestic cat (Felis s. catus). Only six captive individuals (7.7%) were assigned as wildcats in the STRUCTURE analysis (at K = 2), two of which had domestic cat mtDNA haplotypes and only two captive individuals were assigned as purebred wildcats by NewHybrids. These results suggest that the high genetic diversity of the captive population has been caused by admixture with domestic cats. Therefore, the captive population cannot be recommended for further breeding and reintroduction.

Genetic assessments and parentage analysis of captive Bolson tortoises (Gopherus flavomarginatus) inform their "rewilding" in New Mexico

The Bolson tortoise (Gopherus flavomarginatus) is the first species of extirpated megafauna to be repatriated into the United States. In September 2006, 30 individuals were translocated from Arizona to New Mexico with the long-term objective of restoring wild populations via captive propagation. We evaluated mtDNA sequences and allelic diversity among 11 microsatellite loci from the captive population and archived samples collected from wild individuals in Durango, Mexico (n = 28). Both populations exhibited very low genetic diversity and the captive population captured roughly 97.5% of the total wild diversity, making it a promising founder population. Genetic screening of other captive animals (n = 26) potentially suitable for reintroduction uncovered multiple hybrid G. flavomarginatus×G. polyphemus, which were ineligible for repatriation; only three of these individuals were verified as purebred G. flavomarginatus. We used these genetic data to inform mate pairing, reduce the potential for inbreeding and to monitor the maintenance of genetic diversity in the captive population. After six years of successful propagation, we analyzed the parentage of 241 hatchlings to assess the maintenance of genetic diversity. Not all adults contributed equally to successive generations. Most yearly cohorts of hatchlings failed to capture the diversity of the parental population. However, overlapping generations of tortoises helped to alleviate genetic loss because the entire six-year cohort of hatchlings contained the allelic diversity of the parental population. Polyandry and sperm storage occurred in the captives and future management strategies must consider such events.

[Cognitive enrichment in zoo and farm animals--implications for animal behaviour and welfare]

Animals in the wild are facing a wide variety of challenges and ever-changing environmental stimuli. For successful coping, animals use both innate behavioural programs and their cognitive skills. In contrast, zoo- and farm animals have to cope with restricted husbandry conditions, which offer only few opportunities to adequately satisfy their various needs. Consequences could be sensory and cognitive underchallenge that can cause boredom and frustration as well as behavioural disturbances. Initially intended for improvement of management and husbandry, different forms of operant behavioural training have been applied firstly in zoo- and later also in farm animals. It has been suggested that successful coping with appropriate cognitive challenges is a source of positive emotions and may lead to improved welfare. Under the term cognitive enrichment, new approaches have been developed to integrate cognitive challenges into the housing of zoo- and farm animals. The present article reviews actual research in the field. Previous results indicate that, beyond improvement of management and handling routines, such approaches can positively affect animal behaviour and welfare. The combination of explorative and appetitive behaviour with successful learning improves environmental predictability and controllability for the animals, activates reward-related brain systems and can directly affect emotional processes of appraisal. For practical implementation in farm animal husbandry, it sounds promising to link individual access to e.g. automated feeders or milking systems with previously conditioned stimuli and/or discriminatory learning tasks. First experimental approaches in pigs, dwarf goats and cattle are available and will be discussed in the present article.

Evidence for introgressive hybridization of captive markhor (Capra falconeri) with domestic goat: cautions for reintroduction

Markhors (Capra falconeri) are among the most endangered mammal species, and several conservation measures, including ex situ breeding, are implemented to prevent their extinction. We studied sequence diversity and differentiation of the first hypervariable segment of the mitochondrial DNA control region among C. f. heptneri and C. f. megaceros kept in four zoos in relationship to lineages of other wild and domestic goats, to assess for the first time the level of molecular distinctness and variability among those subspecies, and to check for possible introgression by related Capra taxa, such as domestic goats. Levels of differentiation between some Capra falconeri lineages and modern domestic goats were similar to levels between other wild goat species (i.e., Capra aegagrus, Capra ibex) and domestic goats. Among pure markhor lineages, paraphyly was observed for C. f. heptneri, suggesting occurrence of shared ancestral polymorphism among markhor subspecies and/or ancient or recent gene exchange between subspecies. Interestingly, 35.7% of all studied markhors from three zoos are introgressed by the domestic goat. Furthermore, despite relatively small breeding group sizes, markhors have maintained a relatively high proportion of mtDNA variation within zoo groups. In any case, the existence of markhors introgressed with domestic goat DNA in zoos should be considered when selecting markhors for ex situ breeding programs with the aim of building up a stock for later reintroduction into the wild.

New Robertsonian translocation chromosomes in captive Thai gaur (Bos gaurus readei)

Robertsonian translocation have been well documented in domestic cattle, with the most commonly occurring fusion involving chromosomes 1 and 29. The widespread nature of this translocation is indicative of its ancient origin. Fifty Giemsa's stained metaphase spreads derived from lymphocyte cultures of the Thai gaur were analyzed for each animal. The Thai gaur had diploid chromosome number of 2n = 57 in male and 2n = 56 in female instead of the normal 2n = 58. The 2n = 57 in male chromosomes presence of an extra submetacentric chromosome and loss of two acrocentric chromosomes was observed [XY, 57, rob (1;29)]. The 2n = 56 in female chromosomes presence of two extra submetacentric chromosomes and loss of four acrocentric chromosomes was observed [XX, 56, rob (1;29)]. Results from the Giemsa's stained analyses confirm that the two autosomes (2n = 57) and four autosomes (2n = 56) involved in the translocation are the bovine homologues 1 and 29.

Parthenogenesis in Komodo dragons

Parthenogenesis, the production of offspring without fertilization by a male, is rare in vertebrate species, which usually reproduce after fusion of male and female gametes. Here we use genetic fingerprinting to identify parthenogenetic offspring produced by two female Komodo dragons (Varanus komodoensis) that had been kept at separate institutions and isolated from males; one of these females subsequently produced additional offspring sexually. This reproductive plasticity indicates that female Komodo dragons may switch between asexual and sexual reproduction, depending on the availability of a mate--a finding that has implications for the breeding of this threatened species in captivity. Most zoos keep only females, with males being moved between zoos for mating, but perhaps they should be kept together to avoid triggering parthenogenesis and thereby decreasing genetic diversity.

An investigation of inbreeding depression and purging in captive pedigreed populations

We use regression models to investigate the effects of inbreeding in 119 zoo populations, encompassing 88 species of mammals, birds, reptiles and amphibians. Meta-analyses show that inbreeding depression for neonatal survival was significant across the 119 populations although the severity of inbreeding depression appears to vary among taxa. However, few predictors of a population's response to inbreeding are found reliable. The models are most likely to detect inbreeding depression in large populations, that is, in populations in which their statistical power is maximised. Purging was found to be significant in 14 populations and a significant trend of purging was found across populations. The change in inbreeding depression due to purging averaged across the 119 populations is <1%, however, suggesting that the fitness benefits of purging are rarely appreciable. The study re-emphasises the necessity to avoid inbreeding in captive breeding programmes and shows that purging cannot be relied upon to remove deleterious alleles from zoo populations.

A genetic diversity comparison between captive individuals and wild individuals of Elliot's Pheasant (Syrmaticus ellioti) using mitochondrial DNA

Maintaining genetic diversity is a major issue in conservation biology. In this study, we demonstrate the differences of genetic diversity levels between wild and captive individuals of Elliot's Pheasant Syrmaticus ellioti. Wild individuals showed a higher genetic diversity level than that of the captive individuals. Nucleotide diversity and haplotype diversity of wild individuals were 0.00628 and 0.993, while those of captive individuals were 0.00150 and 0.584 respectively. Only 3 haplotypes of mtDNA control region sequence were identified among 36 captive individuals, while 16 unique haplotypes were identified among the 17 wild individuals in this study. One captive haplotype was shared by a wild individual from Anhui Province. It is concluded that a low number of founders was the likely reason for the lower level genetic diversity of the captive group. Careful genetic management is suggested for captive populations, particularly of such an endangered species, to maintain genetic variability levels.

Comparative studies of mitogen- and antigen-induced lymphocyte proliferation in four captive rhinoceros species

Cellular immune function in four rhinoceros species was evaluated by way of in vitro lymphocyte proliferation responses to mitogenic and antigenic stimuli to establish normative data on white blood cell activity for each species and to identify species-specific differences that might help explain the predisposition of black rhinoceroses (Diceros bicornis) to disease. A cross section of the U.S. rhinoceros population encompassing all four captive species was sampled, including the Sumatran rhinoceros (Dicerorhinus sumatrensis) (n = 3); Indian rhinoceros (Rhinoceros unicornis) (n = 4); African black rhinoceros (n = 16); and African white rhinoceros (Ceratotherium simum) (n = 10). Of the four species evaluated, African black rhinoceroses exhibited the weakest (P < 0.05) lymphocyte proliferative responses to the mitogens: pokeweed (0.1 microg/ml), phytohemagglutinin (0.3 microg/ml), and concanavalin A (5.0 microg/ml). Total cell density at the end of culture was only 70% of that achieved with lymphocytes isolated from African white rhinoceroses, Indian rhinoceroses, and Sumatran rhinoceroses. However, lymphocyte response to bacterial endotoxin lipopolysaccharide was similar (P > 0.05) across species. Antigenic stimulation produced much weaker responses than mitogenic stimulation. No differences (P > 0.05) were observed among rhinoceros species in response to 1 and 10 microg/ml of Leptospira icterohemorrhagiae or Leptospira gryppotyphosa. Lymphocytes from African white rhinoceroses proliferated weakly in the presence of Aspergillus fumigatus filtrate, whereas lymphocytes from the southern black rhinoceros subspecies appeared slightly suppressed in the presence of increasing doses (0.1, 1, and 10 microg/ml) of Aspergillus filtrate. This comparative data set characterizing lymphocyte proliferation in the rhinoceros reveals several differences in immune cell responses among rhinoceros species and provides some evidence that lymphocytes of captive African black rhinoceroses are less vigorous than those of the other rhinoceros species.

Molecular scatology as a tool to study diet: analysis of prey DNA in scats from captive Steller sea lions

The DNA of prey present in animal scats may provide a valuable source of information for dietary studies. We conducted a captive feeding trial to test whether prey DNA could be reliably detected in scat samples from Steller sea lions (Eumetopias jubatus). Two sea lions were fed a diet of fish (five species) and squid (one species), and DNA was extracted from the soft component of collected scats. Most of the DNA obtained came from the predator, but prey DNA could be amplified using prey-specific primers. The four prey species fed in consistent daily proportions throughout the trial were detected in more than 90% of the scat DNA extractions. Squid and sockeye salmon, which were fed as a relatively small percentage of the daily diet, were detected as reliably as the more abundant diet items. Prey detection was erratic in scats collected when the daily diet was fed in two meals that differed in prey composition, suggesting that prey DNA is passed in meal specific pulses. Prey items that were removed from the diet following one day of feeding were only detected in scats collected within 48 h of ingestion. Proportions of fish DNA present in eight scat samples (evaluated through the screening of clone libraries) were roughly proportional to the mass of prey items consumed, raising the possibility that DNA quantification methods could provide semi-quantitative diet composition data. This study should be of broad interest to researchers studying diet since it highlights an approach that can accurately identify prey species and is not dependent on prey hard parts surviving digestion.

Ex situ population management in the absence of pedigree information

For captive breeding to play a significant role in conservation, ex situ populations must be scientifically managed to meet objective goals for retaining representative genetic variation. Imperfect genealogical information requires fundamental assumptions to be made that may bias downstream measures of genetic importance, upon which management decisions are based. The impacts of such assumptions are most pronounced within breeding programmes characterized by a high proportion of individuals of unknown ancestry, as exemplified by the large captive population of the St Vincent parrot (Amazona guildingii). The degree to which microsatellite-based estimates of relatedness may improve upon the assumptions of conventional pedigree-based management was investigated using genotypic data collected at eight microsatellite loci and two marker-based relatedness estimators. The measure, rxyLR, was found to explain the highest amount of variation in true relatedness. Integration of pairwise estimates of founder relatedness with studbook data transformed current understanding of the relatedness structure of the A. guildingii population from two subgroups characterized by a high and low degree of relatedness, respectively, to a situation where all 72 individuals are prioritized for breeding according to their estimated mean kinships. Furthermore, the discovery of opposing, directional bias exhibited by rxyLR and rxyQG in assigning dyads to a given relationship category suggests that an approach that utilizes a combination of pairwise relatedness estimators may provide the most genetic information for balancing the dual considerations of maximizing gene diversity and minimizing inbreeding in developing breeding recommendations.

Comparison of phenotypic and genotypic markers for characterization of an outbreak of Salmonella serotype Havana in captive raptors

AIMS

To establish a typing method for tracing the epidemic relationship of 16 strains of Salmonella serotype Havana isolated from captive raptors showing no symptomatology and residing in a wildlife hospital in Spain.

METHODS AND RESULTS

Antimicrobial susceptibility testing, ribotyping, pulsed field gel electrophoresis (PFGE) and amplified fragment length polymorphism (AFLP) methodology were applied. Ten unrelated strains of serotype Havana were included as a control group to provide a basis of for the efficiency of the different markers used. All outbreak-related strains were resistant to nalidixic acid and streptomycin and showed the same ripotype, pulsotype and AFLP pattern.

CONCLUSIONS

This is the first time that AFLP analysis has been tested with serotype Havana isolates and it has demonstrated to be the most useful epidemiological tool for discriminating between unrelated and outbreak-related strains of this serotype. The results obtained suggest that all the Salmonella serotype Havana isolates represented a common outbreak strain whose origin of contamination could not be established although it is thought that it was the poultry meat used for raptors'diet.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our study suggests the importance of microbiological analysis of these products in order to prevent contamination and dissemination of Salmonellae in this kind of Hospital.

Chromosome painting in farm, pet and wild animal species

Among the advanced karyotype analysis approaches embraced by animal cytogenetics during the past decade, chromosome painting has had the greatest impact. Generation of chromosome specific paints is considered pivotal to his development. Additionally, ability to use these paints across species (referred to as Zoo-FISH or comparative painting) is undisputedly the most important breakthrough that has contributed to our ability to compare karyotypes of a wide range of evolutionarily highly diverged chromosome painting, and makes them aware of the tools/resources available to carry out this research in a variety of animal species. An overview of the current status of comparative chromosome painting results across closely as well as distantly related species is presented. Findings from different studies show how some segmental syntenies are more conserved as compared to others. The comparisons provide insight into the likely constitution of a vertebrate/mammalian ancestral karyotype and help understand some of the intricacies about karyotype evolution. Importance of comparative painting in setting the stage for rapid development of gene maps in a number of economically important species is elaborated.

Captive breeding, reintroduction, and the conservation genetics of black and white ruffed lemurs, Varecia variegata variegata

A character-based phylogenetic species concept approach was used to examine conservation unit status for three wild populations of black and white ruffed lemurs, Varecia vareigata variegata, from Betampona (N = 3), Manombo (N = 6), and Ranomafana (N = 14), Madagascar. Population aggregation analysis was performed on 548 bp from the control region (D-loop) of the mitochondrial DNA (mtDNA). Twenty-one diagnostic sites were found to differentiate the Betampona (northern) population from the Manombo/Ranomafana (southern) populations. Additionally, individuals from the North American captive population (N = 11) and from Parc Ivoloina, Madagascar (N = 6) were examined for the same mtDNA fragment. The captive animals more closely resembled the southern populations and the Parc Ivoloina animals were more similar to the northern population. However, the inclusion of these ex situ animals reduced the number of diagnostic sites differentiating the northern and southern populations. Our genetic data were used to assess the ongoing management strategy for reintroducing individuals into the Betampona population and for introducing new founders into the ex situ population. This study demonstrates the utility of combining genetic information with a consideration of conservation priorities in evaluating the implementation of management strategies.

Conservation genetics of Nordic carnivores: lessons from zoos

This paper summarizes results from genetic studies of Nordic carnivore populations bred in captivity. The conservation genetic implications of those results for the management of wild populations of the same species are discussed. Inbreeding depression has been documented in the brown bear (Ursus arctos), wolf (Canis lupus), and lynx (Lynx lynx) populations held in Nordic zoos. The characters negatively affected by inbreeding include litter size (brown bear and wolf), longevity (lynx and wolf), female reproduction, and weight (wolf). In addition, hereditary defects caused by single autosomal alleles occur in the wolf and brown bear populations. These deleterious alleles cause blindness (wolf) and albinism (brown bear) in the homozygous state. The amount of inbreeding depression observed in Nordic carnivores are similar to that documented in other species. The captive populations have the same genetic background as the current wild ones and inbreeding depression is therefore a potential threat to wild carnivore populations in Sweden. This threat is presently not being adequately recognized in the management of these species. Frequently occurring misunderstandings regarding the kind of conclusions that can be drawn from the presented genetic observations are also discussed.

Special challenges of maintaining wildlife in captivity in Europe and Asia

In the second half of the 20th century, populations of many wild animal species have been established in captivity for various purposes (e.g. education, conservation, research, farming) and many are kept as companion animals. With continuing human pressure on the environment, captive or semi-captive management is likely to become a component in the conservation of an increasing range of species throughout Europe and Asia. The management of small and divided populations (some of which may be in zoos while some are free-ranging) requires careful control to minimise loss of genetic diversity. This, in turn, may require movements of animals or germplasm between sub-populations. A potentially serious hazard associated with these translocations is the accidental introduction of infectious agents into populations which have hitherto been geographically or ecologically isolated from these agents. When planning translocations, the state veterinary authorities of both importing and exporting countries should be contacted at an early stage for details of legal requirements in relation to animal health, welfare and conservation. Animal health legislation is mostly aimed at preventing disease in man and domestic animals, and further disease control measures may be required when translocating wild animals. In addition to the need for efforts in ensuring genetic diversity and disease control, good husbandry and welfare can often be challenging in species about which relatively little is known. A variety of organisations are involved in coordinating captive breeding programmes in Europe and Asia, and some of these organisations and the routes through which they can be identified are mentioned here.

DNA fingerprinting in relation to male dominance and paternity in a captive colony of tammar wallabies (Macropus eugenii)

The tammar wallaby has a polygynous mating system in which the dominant male usually controls initial access to oestrous females by mating first and then guarding the female from the advances of other subordinate males. In this study we used DNA fingerprinting with a human 3' hypervariable region (HVR) alpha globin probe to examine the paternity of pouch young progeny from 13 female tammars that were given continual access during the breeding season to a group of four sexually mature males. Constant individual-specific DNA profiles were observed for each animal. Paternity for 22 pouch young was successfully assigned using visual and computer-based analyses. However, no statistical difference was observed between the number of young sired by any of the four males (chi 2 = 2, d.f. = 3, P > 0.1). Mate guarding by the dominant male in our captive breeding group was not, therefore, sufficient to prevent successful subsequent matings by subordinates nor to enhance the genetic contribution of this male to the next generation. In each analysis, visual and computer assignments of paternity coincided, and these concurred with the results of a relatedness test which found that a large number of DNA bands were shared by sires and their progeny. The results from this paternity study show that first mating and subsequent mate guarding by the dominant male tammar wallaby in our captive group do not significantly skew the outcome of paternity towards this male and away from other males that subsequently mate with each female.

Potential contribution of cryopreserved germ plasm to the preservation of genetic diversity and conservation of endangered species in captivity

Demographic and genetic objectives of captive propagation programs for endangered species focus on establishing demographically secure populations that maintain adequate levels of genetic diversity. Long-term storage and utilization of cryopreserved germ plasm could extend the population's generation length and allow higher levels of genetic variation to be maintained in smaller populations. Since fewer breeding animals would be needed, more species would be "rescued" from extinction using the cage facilities currently available at existing institutions. Doubling generation lengths for callitrichid primates through use of cryopreservation could almost triple the number of species that could be rescued in world zoos. Additionally, long-term cryopreservation would allow for a third population, that of the frozen zoo. Three-way exchange of germ from germ plasm banks to captive and wild populations would increase genetic diversity at reduced risk and expense. Advances in reproductive technology and better understanding of the reproductive physiology of these animal populations are necessary to permit routine application of artificial insemination and embryo transfer using frozen-stored germ plasm.

Restriction fragment length polymorphism analysis of zoo animals using HaeIII and four single-locus probes

Using HaeIII as the restriction endonuclease, restriction fragment length polymorphism analysis of dried blood samples from various animals was conducted. Single-locus probes D2S44, D10S28, D1S7, and D4S139, as well as monomorphic probe D7Z2, were used to examine for banding patterns. If bands were present, the samples were further examined for heterogeneity (whether single or multiple bands were observed) and polymorphism (whether variation in band location was shown between the animals studied within a species). Blood samples from animals, including primates, were obtained from Miami Metrozoo, Miami, Florida. Some of the animals were non-related individuals while others were related. Banding patterns were observed in colobus' for D2S44, D1S7, and D4S139; owl monkeys for D2S44; gorillas for D2S44 and D4S139; gibbons for D2S44 and D4S139; siamangs for D2S44, talapoins for DiS7; cranes for D1S7; and otters for D1S7. Based upon these, all of the animals for which a conclusion could be drawn appeared to be homozygous and monomorphic (exhibited only an invariant single band) for the loci examined except colobus' for D4S139, gorillas for D4S139, cranes for D1S7, and otters for D1S7.

Susceptibility of captive wildfowl to avian tuberculosis: the importance of genetic and environmental factors

This study reports the findings of an epidemiological survey of death due to avian tuberculosis in the captive collection of wildfowl at The Wildfowl and Wetlands Trust Centre, Slimbridge, Gloucestershire. Both genetic and environmental factors have been shown to affect the incidence of, and the birds' susceptibility to, the disease. Seasonal body condition was related to the occurrence of death due to the disease in both males and females. Birds from either hot or cold climates appeared to have a higher incidence than those from temperate climates. What the birds ate did not affect incidence but the method they used for obtaining their food did. Higher susceptibility was found in those species evolved for marine or arboreal habitats. Anomalies in susceptibility which suggest a higher level of genetic immunity in some groups have also been found. Reasons are put forward to explain these findings.

Mammalian cytogenetics and conservation of species

The proposition is examined that cytogenetic studies are needed in the conservation of wild captive animals. Several cases of polymorphic species have hybridized to produce infertile offspring. In several gazelle species, this accidental hybridization among look-alike animals has led to the extinction of zoo populations. The suggestion that this is always the result of inbreeding is thus erroneous. Cytogenetic study is also needed in animals that are destined for reintroduction, as accidental release of chromosomally different species is counterproductive to the reestablishment of wild stock. Several examples of mammalian species that have flourished from an extremely small founder stock are here examined to draw attention to the possibility that "inbreeding" is not invariably disadvantageous. The karyotypes of two hybridizing Kobus species with divergent chromosomal numbers are described.

Evidence of loss of a suggested genetic polymorphism in the blood potassium contents of zoo-living Barbary sheep Ammotragus lervia (Pallas 1777)

1. Concentrations of potassium and iron were measured in blood samples of 15 zoo-living Barbary sheep by atomic absorption spectrophotometry. 2. In analogy with the situation in Ovis it is suggested that a blood potassium polymorphism is also found in Ammotragus. 3. However, in the Frankfurt line at least, one of the presumed alleles is likely to be lost due to inbreeding.

Kinship and affiliative behavior patterns in a captive group of Celebes black apes (Macaca nigra)

The influence of matrilineal kinship on four socially affiliative behavior patterns--grooming, contact, proximity, and play--was studied in a little-known primate species, the Celebes black ape (Macaca nigra). Twenty group-living black apes, comprising four genealogical groups, were observed for more than 100 hr; data were collected by the instantaneous scan technique. Animals spent more time than was expected by chance grooming, in contact with, and in proximity to their matrilineal relatives, but they did not play with relatives more than was expected. The proximal mechanisms responsible for these results are unknown, and increased familiarity among matrilineal relatives may have influenced the interaction patterns in the group. The results obtained in this study are similar to those of many others that demonstrate differential behavior toward kin, and they are consistent with the theory that animals may increase their inclusive fitness by interacting preferentially with relatives.

Chromosome identification of the rusty-spotted cat (Felis rubiginosa): one more down and four to go

The chromosomes of the rusty-spotted cat, Felis rubiginosa, of Sri Lanka (Ceylon) were analyzed. Although the 38-chromosome complement of F rubiginosa closely resembles that of several other species, it seems to be unique with only minor variations in the D and F chromosomes. This reduces, from 5 to 4, the number of the 37 recognized world feline species not yet cytogenetically studied. Despite great differences in size and distribution, the feline species of the world are one of the most homogenous families of mammals, with only subtle chromosomal differences separating most species. By comparative cytogenetic analyses, it is becoming possible to map the probable evolutionary pathway of the world's cats.

Inbreeding, mortality, and sex ratio in gaur (Bos gaurus) under captivity

The average inbreeding coefficient for gaur (Bos gaurus H. Smith) born in captivity has ranged from 0.139 to 0.234 per year since 1969. Juvenile mortality is significantly higher among inbred young, and a significantly higher proportion of males occur in inbred than in noninbred offspring.

Surgical correction of familial diaphragmatic hernia of Morgagni in the Golden Lion Tamarin

The Golden Lion Tamarin (Leontopithecus rosalia) is an endangered species of primate indigenous to the coastal rain forest of Brazil. Since 1971 a propagation and behavioral research program has been carried out on a colony of these monkeys at the Zoological Park. Several related animals have died and at necropsy have shown absence of the anterior portion of the diaphragm with a variety of abdominal viscera in the thorax. Diagnostic studies undertaken on the living members of the colony include plain chest radiographs and gastrointestinal series. Four of the animals have been found to have major diaphragmatic defects with the liver, stomach, spleen, colon, and portions of the intestine in the chest. In three of the animals so affected clinical signs of failure-to-thrive were clearly manifest, although one female born in 1968 has reproduced successfully for 8 yr with no deleterious clinical effects from the hernia. Surgical repair of the diaphragm with relocation of the abdominal viscera has been carried out in three of the animals under a combination of intravenous and intra-tracheal anesthesia. The monkeys weighed 550, 685, and 710 g, respectively. All three Tamarins have survived the operative procedure, and subsequently have shown improved clinical status. These cases have been instructive from the genetic point of view, the major anatomical defect, the type of repair necessary, and the postoperative care in small vigorous mammals. Additionally this study documents a familial factor in diaphragmatic defects in higher mammals.

Inbreeding and juvenile mortality in small populations of ungulates

Juvenile mortality of inbred young was higher than that of noninbred young in 15 of 16 species of captive ungulates. In 19 of 25 individual females, belonging to ten species, a larger percentage of young died when the female was mated to a related male than when she was mated to an unrelated male.