Years In Captivity Research Articles

Recent genetic drift in the co-diversified gut bacterial symbionts of laboratory mice.

Laboratory mice (Mus musculus domesticus) harbor gut bacterial strains that are distinct from those of wild mice1 but whose evolutionary histories are poorly understood. Understanding the divergence of laboratory-mouse gut microbiota (LGM) from wild-mouse gut microbiota (WGM) is critical, because LGM and WGM have been previously shown to differentially affect mouse immune-cell proliferation2,3, infection resistance4, cancer progression2, and ability to model drug outcomes for humans5. Here, we show that laboratory mice have retained gut bacterial symbiont lineages that diversified in parallel (co-diversified) with rodent species for > 25 million years, but that LGM strains of these ancestral symbionts have experienced accelerated accumulation of genetic load during the past ~ 120 years of captivity. Compared to closely related WGM strains, co-diversified LGM strains displayed significantly faster genome-wide rates of fixation of nonsynonymous mutations, indicating elevated genetic drift, a difference that was absent in non-co-diversified symbiont clades. Competition experiments in germ-free mice further indicated that LGM strains within co-diversified clades displayed significantly reduced fitness in vivo compared to WGM relatives to an extent not observed within non-co-diversified clades. Thus, stochastic processes (e.g., bottlenecks), not natural selection in the laboratory, have been the predominant evolutionary forces underlying divergence of co-diversified symbiont strains between laboratory and wild house mice. Our results show that gut bacterial lineages conserved in diverse rodent species have acquired novel mutational burdens in laboratory mice, providing an evolutionary rationale for restoring laboratory mice with wild gut bacterial strain diversity.

Performance of Artificial Diets for Zelus renardii (Hemiptera: Reduviidae) Rearing.

Mass production is a prerequisite for using natural enemies in integrated pest management and organic farming. Natural enemies in agroecosystems include predators that prey on insects, which they can subdue while maintaining adequate pest population densities. The Leafhopper Assassin Bug (LAB), Zelus renardii, can be a natural enemy in agroecosystems, selecting its prey for size and mobility. Some of LAB's prey include Philaenus spumarius (L.), Bactrocera oleae (Rossi), Drosophila suzukii (Matsumura), and Macrohomotoma gladiata Kuwayama, suggesting this reduviid for biocontrol agent in various contexts. We reared LABs for two subsequent broods offering living prey and artificial diets. Our data show that the rearing of Z. renardii is feasible with oligidic, meridic, and holidic artificial formulations. Four artificial diets allowed the complete post-embryonic development of LABs in captivity for two successive generations. The accumulated degree-days (ADDs) accurately predict the growth of LABs based on heat accumulation, estimating that up to three generations could grow per year in captivity at the experimented T°C.

The Victims who Refused to be Rescued: Lived Experiences of Victims of Sex Trafficking

While many are at risk of becoming victims of sex trafficking, there are still "unrescued victims". This study seeks to answer why victims of sex trafficking refuse to leave the environment in which they have been and continue to be victimized. It utilized a phenomenological study to reveal the experiences of the victims of sex trafficking through interviews as further supported by a group discussion amongst pimps. The study found that participants' need for income and desires to improve their lifestyle influenced their decision to remain victims. Anent, the victims' pre-victimization life status is linked to their decision to stay/leave. The more destitute the victims, the more likely they are to remain in the sex industry. Furthermore, despite the abuses, victims' perceptions of their victimization have positively shifted over the years of captivity. The participants personally perceived themselves from forced victims to persons who maintain their victimization as profession. The economic-benefit, the deception of the pimps, and culture of the locale collectively play apart in this shift of perception. The study comes to an unusual conclusion about victimization in sex trafficking. Recognizing this phenomenon may prompt better interventions by authorities in developing more inclusive rescue, counseling, and victim-centered programs.

The Victims Who Refused to be Rescued: Lived Experiences of Victims of Sex Trafficking

While many are at risk of becoming victims of sex trafficking, there are still "unrescued victims". This study seeks to answer why victims of sex trafficking refuse to leave the environment in which they have been and continue to be victimized. It utilized a phenomenological study to reveal the experiences of the victims of sex trafficking through interviews as further supported by a group discussion amongst pimps. The study found that participants' need for income and desires to improve their lifestyle influenced their decision to remain victims. Anent, the victims' pre-victimization life status is linked to their decision to stay/leave. The more destitute the victims, the more likely they are to remain in the sex industry. Furthermore, despite the abuses, victims' perceptions of their victimization have positively shifted over the years of captivity. The participants personally perceived themselves from forced victims to persons who maintain their victimization as profession. The economic-benefit, the deception of the pimps, and culture of the locale collectively play apart in this shift of perception. The study comes to an unusual conclusion about victimization in sex trafficking. Recognizing this phenomenon may prompt better interventions by authorities in developing more inclusive rescue, counseling, and victim-centered programs.

“Regency Kingdom”. A Quasi-Monarchist Episode on the Road to an Independent Republic of Poland

The objective of the paper is to indicate selected issues related to the construction of the political system of the future Polish state in 1918. Parallel to the construction of the political system, struggles for independence and the borders of the state, which was reborn after 123 years of captivity, continued. The emergence of centers of power and political institutions in the conditions of geopolitical changes of the last phase of the Great War of 1914–1918 was of utmost importance for the process of shaping the political system. The main links in this process were the Provisional Council of State and the Regency Council.

Laboratory‐bred Longfin Smelt produced offspring in the first year in captivity

AbstractObjectiveThis study aims to develop the culture methods for Longfin Smelt Spirinchus thaleichthys in a laboratory setting, achieving the first production of a fully captive second generation (F2). The objective includes understanding the critical factors influencing the breeding and maturation of this species in captivity, contributing to conservation efforts and potential revival of this threatened species.MethodsLongfin Smelt broodstock were collected from the San Francisco Estuary and reared in controlled conditions at the University of California Davis Fish Conservation and Culture Laboratory (FCCL). The study involved spawning of wild broodstock, rearing of first generation (F1) progeny to adulthood, and subsequent spawning to produce F2 offspring. Key variables such as salinity, temperature, and diet were carefully managed throughout the process. Fertilization and hatching rates were calculated, and the larvae were reared using the same methods to closely monitor and understand their growth and development.ResultFirst generation Longfin Smelt successfully matured and spawned at age 1, earlier than commonly observed in the wild. From five crosses, four produced viable offspring. The study recorded a range of fertilization rates (10–40%) and high hatching rates (75–97%). Salinity was identified as a critical factor in both larval development and adult maturation. While initial larval survival was challenging, the larval rearing system used in this study proved effective.ConclusionThe study represents a major breakthrough in the cultivation of Longfin Smelt, showing that it is possible to complete their life cycle under controlled conditions. It has provided valuable understanding of the maturation and breeding processes in these fish, with an emphasis on the influence of salinity. These outcomes are crucial for conservation strategies, offering the potential to help establish a refuge population and laying the groundwork for further research aimed at refining captive breeding methods for this species.

Selected Problems of Child Care and Upbringing Presented during the 1st National Children’s Congress in 1938

The article describes selected problems of child care and upbringing presented during the 1st National Children’s Congress, which took place in Warsaw on 2–4 October 1938. The congress was an important event for all circles of the Second Polish Republic who wanted to improve the situation of Polish children. The economic crisis, Poland regaining independence after many years of captivity, the syndrome of the young Polish state and the maturing democracy brought many neglects and deficiencies in the care and upbringing of children and young people. The congress became an opportunity not only to highlight them but also to take countermeasures.

Artificial reproduction of the indoor-cultured brackish form of maraena whitefish (Coregonus maraena) under recirculated aquaculture system (RAS) conditions

Maraena whitefish (Coregonus maraena) is a promising coldwater aquaculture species, especially in terms of meat quality. This versatile whitefish species, which inhabits both fresh and brackish waters, including the Baltic Sea, offers promising prospects for aquaculture breeding and cultivation. However, the main problem is the lack of availability of spawners of this species. Therefore, in this study, an attempt was made to raise the spawning stock under controlled conditions and then artificially reproduce the fish to obtain high-quality gametes and then larvae. The conducted research showed that successful culture of maraena whitefish spawners is possible under recirculating aquaculture system (RAS) conditions. The application of proper nutrition and manipulation of environmental conditions allowed the breeding of sexually mature whitefish spawners in less than two years in captivity (meat weight 476 g). Through stimulation of environmental conditions (temperature and photoperiod), it was possible to stimulate the final maturation of gametes of the F1 generation of cultured fish. The use of Ovaprim hormonal stimulation induced 100% of females to ovulate within 10 days of injection, compared to 60% of females in the control group. Additionally, the other examined parameters, such as the pseudogonado-somatic index (PGSI: 11.46% vs. 6.80%), fertilization rate (94.2% vs. 60.1%), embryo survival rate (92.6% vs. 41.1%) and embryo survival rate to the eyed-egg-stage (90.0% vs. 28.0), were significantly higher in the hormonally induced group, finally two times and three times, respectively. The mortality rate of spawners, after spawning and within three months of artificial spawning, was extremely low. The results obtained from the study demonstrate the feasibility of culturing the spawning stock of maraena whitefish in captivity and successfully inducing artificial spawning.

Ultrasonography and CT examination of ovarian follicular development in 'Testudo graeca' during 1 year in captivity.

The Greek or Mediterranean tortoise (Testudo graeca), commonly known as the spur-thighed tortoise, is a species of tortoise in the family Testudinidae that is found in North Africa, Western Asia and Europe. Several species of this genus are under threat in the wild, mainly from habitat destruction therefore, accurate information about the sexual cycle and the exact time of follicular development can be effective in successful reproduction planning and preventing species extinction. The experimental part of this study is focused on the evaluation of the reproductive apparatus of tortoises and development of follicles in ovaries during 1 year by ultrasonography and computed tomography. Ultrasonography and CT scanning was carried out on 10 female 'T. Graeca' tortoises which were maintained at Tehran Eram Zoo from November 2021 to November 2022 (1 year). Ultrasonography and CT exams were performed on all animals. In the first study, on 28 November 2021, the ovarian cycle was characterized by the presence of previtellogenic follicles and atretic follicles. The numbers of follicles were best demonstrated on CT examination. Ultrasonography and CT scan in the second study showed no change in type of follicles from previous study. In the third study, atretic follicles were more than previtellogenic follicles, whereas in the fourth one, the numbers of previtellogenic follicles were more than atretic follicles. In following, at 6 and 29 June 2022, the absence of atretic follicles and just presence of previtellogenic follicles were observed. On 20 July 2022, the presence of a few number of atretic follicles and more previtellogenic follicles were noticed. On 30 July 2022, the absence of atretic follicles and presence of previtellogenic follicles and, for the first time, preovulatory follicles were obvious. In four following studies the absence of atretic follicles and the presence of previtellogenic follicles were diagnosed. In the last study, the absence of atretic follicles and the presence of preovulatory and previtellogenic follicles were observed. In current study, the reproductive cycle of female T. Graeca is evaluated during 1 year in captivity with ultrasonography and CT scan. It can be concluded that in captivity, the reproductive cycle does not result in the formation of eggs or calcareous shells and atretic follicles in the study year continued as before; so this should be highly considered in captivity breeding programmes. This study also revealed that among imaging modalities, CT scan is the best modality for detecting the shape, size, type and numbers of the follicles for further evaluation of location and shape of the follicles.

Back to the wild: movements of a juvenile tiger shark released from a public aquarium.

Sharks are an important draw for aquaria, however, larger species can rarely be kept indefinitely. To date, there has been little work tracking shark movements post-release to the wild. We used high-resolution biologgers to monitor a sub-adult tiger shark's pre- and post-release fine-scale movements following two years of captivity in an aquarium. We also compared its movement to a wild shark tagged nearby. Despite the differences in movement between the two sharks, with vertical oscillations notably absent and greater levels of turning seen from the released shark, the captive shark survived the release. These biologgers improve insight into post-release movements of captive sharks. This article is protected by copyright. All rights reserved.

Advancements in hatchery production of red snapper Lutjanus campechanus: Exclusive use of small strain rotifers as initial prey for larval rearing

AbstractThe red snapper (Lutjanus campechanus) has one of the most valued fisheries in the southeastern United States and has been largely studied for its aquaculture potential with varied results that revealed production challenges. This study focused on addressing challenges in larval rearing and juvenile production of this species. Broodstock fish were acclimated in a 60 m3 tank equipped with recirculating aquaculture system (RAS) and temperature control. After 1 year in captivity, fish volitionally spawned and larval rearing trials were conducted in replicated flow‐through seawater tanks ranging from 0.4 to 2.4 m3, at a temperature range of 24–26°C. Enriched s‐strain rotifers, Brachionus rotundiformis (lorica length of 100–210 μm), were used for first feeding. Enriched Artemia sp. were gradually introduced after 18 days post hatch (DPH). The survival rate before metamorphosis (12 DPH) averaged 66.09 ± 0.08%. Survival rate from yolk‐sac larvae to post‐metamorphic early juvenile averaged 4.43 ± 0.01%. At 40 DPH, early red snapper juveniles averaged 0.35 ± 0.02 g in weight and 28.83 ± 0.60 mm in standard length. A total of 31,849 fully weaned juveniles were harvested. This study demonstrates that small strain rotifers can be used exclusively as first feeding prey organism for red snapper larvae, representing a significant advancement for red snapper juvenile production.

Effect of ageing on the cardiac activity of the small primate Microcebus murinus

Age is an important factor of comorbidity in the development of cardiovascular diseases. Regardless of lifestyle, aged people suffer from maximal heart rate (HR) and HR variability (HRV) decrease that could impair blood circulation, tissue oxygenation and consequently self-sufficiency. Given the increase of old people in modern societies it is important to study the effect of ageing on the heart to treat the related consequence on the body physiology. To study the effect of aging on HR dynamics it is important to use appropriate animal models that could replicate the cardiac physiology, but also the neural environment that modulates HR in aged patients. The small primate Microcebus murinus, also known as gray mouse lemur (ML), responds to these criteria. Indeed, differently from mice it spontaneously develops neurodegenerative diseases. In addition, although ML lies in between the size of mice and rats, it can live up to 12 years in captivity, generating about 3 billion heartbeats in a lifetime. Thus, ML generates as many heartbeats as humans in a lifetime and about three times more than mice. To study HR and HRV in ML, we used a mini Holter and we developed a jacket to record surface electrocardiograms (ECGs) in young (1–5 years) and aged (6–10 years) animals of both genders. These experiments showed HR decrease in correlation with age in male MLs, but not in females. To get insights on the sympathetic tone of ML, we measured the coefficient of variability of the interval between two heartbeats (CVRR). Under handling stress, we found higher CVRR in aged versus young ML males, indicative of lower sympathetic tone. Conversely, the index of short-term HRV, related to parasympathetic modulation (RMSSD), showed no difference in response to stress in young and aged MLs of both genders. Next, we measured the concentration of adrenaline and noradrenaline in the urines of ML of different age and both genders. Accordingly, with our measurements of HRV we found a tendency of decrease in the urine concentration of noradrenaline in aged versus young ML males. Our preliminary results suggest that age impairs the autonomic regulation of HR, but this effect is evident in aged ML males and not in females.

Survival and establishment of captive‐reared and translocated giant gartersnakes after release

AbstractMany imperiled species face increasing extinction risk that requires interventional management like translocation or captive rearing. The use of translocations to successfully restore or create populations requires that animals survive at recipient sites, information that is often lacking for imperiled species and that can be risky to acquire if not obtained before a species has dwindled in number. The giant gartersnake (Thamnophis gigas), a semiaquatic snake endemic to the Central Valley in California, USA, has declined after losing >90% of its historical habitat and may benefit from successful translocations to protected habitat. We released adult and captive‐reared juvenile snakes from 2 donor sites into a recently restored wetland in 2019 and 2020 and compared their survival, movement, and activity using radio‐telemetry through 2021. We monitored juvenile survival for 2 years in captivity after birth and then estimated post‐release survival at the recipient site using radio‐telemetry. Just 8% of translocated adult snakes survived >801 days (95% CI = 1–64%) compared with 39% of resident snakes at the donor sites surviving >1,154 days (95% CI = 23–68%). This equated to annualized survival rates of translocated adults ( = 0.32, 95% CI = 0.12–0.82) that were roughly half that of resident snakes ( = 0.74, 95% CI = 0.63–0.89). Translocation was negatively correlated with survival, but movement and activity received little support in models. Seventy‐six percent of juvenile snakes survived captivity and, once released, juvenile survival was 60% (95% CI = 38–94%) for the 4‐month monitoring period before winter. It is unclear why survival of translocated adult snakes was lower than that of resident snakes, but there was little evidence for differences in behavior (e.g., increased surface activity, average distance moved, emigration from the translocation site) that are commonly cited causes of mortality in other translocation studies. Our results suggest that, in the absence of a clear understanding as to what contributes to adult survival after release to a new site, future work using captive‐rearing and juvenile translocation may be more promising for establishing and recovering populations than just translocating adults given the high survival of juveniles.

Deciphering Mary Stuart’s lost letters from 1578-1584

Mary Stuart, Queen of Scots (1542–1587), has left an extensive corpus of letters held in various archive collections. There is evidence, however that other letters from Mary Stuart are missing from those collections, such as letters referenced in other sources but not found elsewhere. In Under the Molehill – an Elizabethan Spy Story, John Bossy writes that a secret correspondence with her associates and allies, prior to its compromise in mid-1583, was “kept so secure that none of it has survived, and we don’t know what was in it.” We have found over 55 letters fully in cipher in the Bibliothèque nationale de France, which, after we broke the code and deciphered the letters, unexpectedly turned out to be letters from Mary Stuart, addressed mostly to Michel de Castelnau Mauvissière, the French ambassador to England. Written between 1578 and 1584, those newly deciphered letters are most likely part of the aforementioned secret correspondence considered to have been lost, and they constitute a voluminous body of new primary material on Mary Stuart – about 50,000 words in total, shedding new light on some of her years of captivity in England.

Effects of Breeding Forest Musk Deer on Soil Bacterial Community Structure

Breeding captive forest musk deer is an important way to obtain musk resources, but it also causes changes in the ecological environment of the breeding site. This study compared the changes in soil bacterial communities inside and outside the captive breeding site and tried to find out its influencing factors. High-throughput sequencing analysis and other methods were used to analyze the changes in the bacterial community structure in the natural soil and forest surrounding the musk deer site after 4 years of captivity. The results showed that the main dominant phyla in the captive soil samples were Proteobacteria, Acidobacteria and Chloroflexi. In order, Sphingomonadales (8.7%), Acidobacteriales (9.9%) and Solibacterales (6.1%) were dominant in the captive soil, while Rhizobiales (11.3%) and Gaiellales (6.2%) were found in non-captive soil. The main soil-specific microorganisms under captive conditions were Burkholderiales, Pseudomonadales and Sphingomadales. These microorganisms mainly gather at the order level and can be used as indicator microorganisms. A canonical correspondence analysis (CCA) showed that the microbial diversity in captivity soil was significantly affected by the contents of organic matter, available phosphorus and total nitrogen. These results will provide a basis for the healthy breeding of animals and shed light on the protection of the ecological environment in the Bashan Mountains of Qinling.

Staphylococcus aureus lineages associated with a free-ranging population of the fruit bat Pteropus livingstonii retained over 25 years in captivity

Conservation of endangered species has become increasingly complex, and costly interventions to protect wildlife require a robust scientific evidence base. This includes consideration of the role of the microbiome in preserving animal health. Captivity introduces stressors not encountered in the wild including environmental factors and exposure to exotic species, humans and antimicrobial drugs. These stressors may perturb the microbiomes of wild animals, with negative consequences for their health and welfare and hence the success of the conservation project, and ultimately the risk of release of non-native organisms into native ecosystems. We compared the genomes of Staphylococcus aureus colonising critically endangered Livingstone’s fruit bats (Pteropus livingstonii) which have been in a captive breeding programme for 25 years, with those from bats in the endemic founder population free ranging in the Comoros Republic. Using whole genome sequencing, we compared 47 isolates from captive bats with 37 isolates from those free ranging in the Comoros Republic. Our findings demonstrate unexpected resilience in the bacteria carried, with the captive bats largely retaining the same two distinctive lineages carried at the time of capture. In addition, we found evidence of genomic changes which suggest specific adaptations to the bat host.

Создатель Товарищества пролетарского искусства в Берлине Фридрих Вильгельм Брасс: первый опыт биографии

The purpose of this article is to study the life and activity of Friedrich Wilhelm Brass, founder of Genossenschaft for Proletarian Art in Berlin (1920). Friedrich Wilhelm Brass (1873–1931) throughout his life sought to combine the commercial interests of a contemporary art dealer with the ideas of the social reorganization of the world. One of the first to call himself a communist in Germany, he created in 1920 in Berlin the Genossenschaft for Proletarian Art, the collection of which became the first contemporary western art brought to Soviet Russia. On the basis of this collection kept in the Hermitage and the Russian Academy of Arts, archival materials and work in museum collections in Germany, the history of the emergence of the Genossenschaft in Berlin in 1920, the composition of the participants and the biography of its creator are reconstructed. The relevance and novelty of the article is due to the lack of scientific research on this issue discovered by the author in his works. The life path of F.W. Brass is consistently considered. Trained as a craftsman in Krefeld, Brass made several attempts to establish an art trade there, primarily aimed at the workers’ milieu. A member of the Social Democratic Party of Germany, he tried to interest the party in the prospect of such educational and agitational work. These initiatives proved to be financially untenable. Brass later worked at the German Workshops Hellerau, where the manufacturer Karl Schmidt implemented a project for the mass production of furniture designed by leading European designers and oriented to the widest and most democratic market. During the First World War, Brass was mobilized and spent several years in captivity in Russia, where he met the revolution and returned to Germany in 1919 as a convinced supporter of the communist reorganization of the world. After the November Revolution, several artistic organizations arose in Berlin, whose activities were directed towards the proletariat (the Workers’ Council for Art, the Association of Socialist Artists, the Union for Proletarian Culture, the Proletarian Theatre of Erwin Piscator, etc.). Among them was the Genossenschaft for Proletarian Art of the communist Brass, who collected the works of left-wing artists, mainly expressionists of the first and second generation. Like most of these artistic initiatives, the Brass Genossenschaft could not survive the economic crisis. The unique collection of the Genossenschaft was acquired during a trip to Germany by Comintern Chairman G. Zinoviev in October 1920 and brought to Soviet Russia. Later, during the years of the Weimar Republic, Brass no longer undertook such ambitious projects, continuing to trade in the works of left-wing artists. He worked in Hagen and Düsseldorf, where he died in 1931. The author comes to the conclusion that the figure of Brass represents a new type of entrepreneur for the art market of the 20th century, focused primarily on the promotion of the latest art among the workers, agitation for a new life in the language of art.

Mo Koundje (“Mok”): the life of a western lowland gorilla (c.1929–1938)

Mo Koundje (“Mok”) was a western lowland gorilla ( Gorilla gorilla gorilla) whose remains form part of the collection of Leeds Museums and Galleries. Before his early death from Bright’s disease (nephritis), he was hugely popular during six years of captivity spent at London Zoo. Newspapers from around the United Kingdom and across the globe reported Mok’s arrival at the Zoo, his exploits, illnesses and demise. While the archives of the Zoological Society of London tell us about the latter part of Mok’s life, tracing his life and journey before entering Europe has proved more difficult. However, French colonial archives held at the Archives nationales d’outre-mer, Aix-en-Provence, give glimpses of the life of his previous owner, Jean Charles André Capagorry, allowing us to piece together the long journey Mok made from a Congolese forest to a museum in Leeds.

02. First reproduction of Panha’s crocodile newt Tylototriton panhai in captivity, with a description of the courtship behaviour, eggs and larval development

Amphibians are facing extinction on a global scale and maintaining small populations of threatened or endangered species in captivity is essential. In connection with potential captive breeding of Panha’s crocodile newt, Tylototriton panhai, we report a detailed husbandry protocol and describe breeding and mating behaviour. After six years in captivity, a group of two adult females and six males, tentatively identified as T. panhai, successfully reproduced for the first time on 24th June 2020 after a heavy rainstorm and two subsequent days of precipitation when water temperatures in a large aquaterrarium placed outdoors were 18-21 °C. The complete courtship behaviour consisted of five main stages: i/ approach; ii/ nuptial dance; iii/ amplexus; iv/ spermatophore deposition; v/ fertilisation. The two females laid a total of 84 eggs (41 and 43 eggs each) that were deposited on land in clutches of 4-22 eggs or even singly. Egg size averaged 12.6 ± 0.4 mm and the mean size of the embryo capsule 5.1 ± 0.1 (n=84). The egg hatch success rate was ~80% and on hatching the larvae moved to the water at the bottom of the aquaterrarium. By 7-9 days after hatching the total larval length was 11.89-13.78 mm (n=67). Diagnostic morphological characters are provided for stages 30-46. Metamorphosis occurred at 99-102 days and efts started to move to land at an average total length of 56.2 mm and weight of 0.6-0.9 g.

First reproduction of Panha’s crocodile newt Tylototriton panhai in captivity, with a description of the courtship behaviour, eggs and larval development

Amphibians are facing extinction on a global scale and maintaining small populations of threatened or endangered species in captivity is essential. In connection with potential captive breeding of Panha’s crocodile newt, Tylototriton panhai, we report a detailed husbandry protocol and describe breeding and mating behaviour. After six years in captivity, a group of two adult females and six males, tentatively identified as T. panhai, successfully reproduced for the first time on 24th June 2020 after a heavy rainstorm and two subsequent days of precipitation when water temperatures in a large aquaterrarium placed outdoors were 18-21 °C. The complete courtship behaviour consisted of five main stages: i/ approach; ii/ nuptial dance; iii/ amplexus; iv/ spermatophore deposition; v/ fertilisation. The two females laid a total of 84 eggs (41 and 43 eggs each) that were deposited on land in clutches of 4-22 eggs or even singly. Egg size averaged 12.6 ± 0.4 mm and the mean size of the embryo capsule 5.1 ± 0.1 (n=84). The egg hatch success rate was ~80% and on hatching the larvae moved to the water at the bottom of the aquaterrarium. By 7-9 days after hatching the total larval length was 11.89-13.78 mm (n=67). Diagnostic morphological characters are provided for stages 30-46. Metamorphosis occurred at 99-102 days and efts started to move to land at an average total length of 56.2 mm and weight of 0.6-0.9 g