Search

Behavior and innervation suggest a high tactile sensitivity of elephant trunks. To clarify the tactile trunk periphery we studied whiskers with the following findings. Whisker density is high at the trunk tip and African savanna elephants have more trunk tip whiskers than Asian elephants. Adult elephants show striking lateralized whisker abrasion caused by lateralized trunk behavior. Elephant whiskers are thick and show little tapering. Whisker follicles are large, lack a ring sinus and their organization varies across the trunk. Follicles are innervated by ~90 axons from multiple nerves. Because elephants don't whisk, trunk movements determine whisker contacts. Whisker-arrays on the ventral trunk-ridge contact objects balanced on the ventral trunk. Trunk whiskers differ from the mobile, thin and tapered facial whiskers that sample peri-rostrum space symmetrically in many mammals. We suggest their distinctive features—being thick, non-tapered, lateralized and arranged in specific high-density arrays—evolved along with the manipulative capacities of the trunk. An anatomical study of the structure, distribution and use of whiskers on the elephant trunk reveal unique characteristics that may facilitate its manipulative capabilities. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Complex odontoma is a rare odontogenic lesion reported in rodents (order: Rodentia) and odd-toed ungulates (order: Perissodactyla), to name a few, and only in bovine animals of the order Artiodactyla. A 3-year-old female giraffe presented with a steadily proliferating, firm mass in the rostral mandible. With further expansion and ulceration of the mass, the general condition of the giraffe deteriorated and it was euthanized. Post-mortem examination revealed greyish–white tissue with an irregular arrangement of yellowish hard tissue arranged in thin plates and intermingled areas of greyish soft tissue. Histologically, irregular proliferated odontogenic epithelium and mesenchyme, dentin, cementum and empty spaces, suggestive of decalcified enamel, were present. These findings are consistent with a diagnosis of complex odontoma, which should be added to the differential diagnoses of oral tissue proliferations in giraffes. To our knowledge, this is the first description of a complex odontoma in a giraffe. [ABSTRACT FROM AUTHOR]

COVID-19 has changed the world at unprecedented pace. The measures imposed by governments across the globe for containing the pandemic have severely affected all facets of economy and society, including scientific progress. Сonservation research has not been exempt from these negative effects, which we here summarize for the B io R escue project, aiming at saving the northern white rhinoceros (Ceratotherium simum cottoni), an important Central African keystone species, of which only two female individuals are left. The development of advanced assisted reproduction and stem-cell technologies to achieve this goal involves experts across five continents. Maintaining international collaborations under conditions of national shut-down and travel restrictions poses major challenges. The associated ethical implications and consequences are particularly troublesome when it comes to research directed at protecting biological diversity – all the more in the light of increasing evidence that biodiversity and intact ecological habitats might limit the spread of novel pathogens. [ABSTRACT FROM AUTHOR]

In captive rhinoceros stillbirth and perinatal death are recorded at a rate of 6–17% in the various species. At the same time there is a substantial lack of knowledge on rhinoceros parturition. Yet, predicting parameters for birth and progress of parturition are fundamental for the recognition of dystocia and perinatal problems. Therefore, we here intended to pay close attention to the Achilles heel of the 1.5–2.5 year reproduction cycle in rhinoceros, the parturition. For the prediction of parturition we recorded timelines for pre-birth udder development, genital swelling, milk production, behavioral unrest, and decrease of serum progesterone concentration and the gestational length in 19 white rhinoceros. First, second and third labour stage, foetal presentation and events in perinatal period were recorded to describe normal parturition and establish a guideline for better birth management in rhinoceros. Udder development and genital swelling were observed 3 and 2 weeks prior birth, respectively. Milk production was observed to start up to 3 weeks prior birth and increased significantly in the last week with most significant increase one day before parturition to 50.6 ± 45.4 mL (p < 0.006). Serum progesterone concentration started to decrease 7 days prior parturition and more significantly 48 h before parturition. While behavioral unrest and first stage labour was not observed reliably in all females the break of foetal waters and thus the start of second stage labour was unmistakably observed. Second stage labour, when foetal membranes had ruptured until the foetus was born, took 1:50 ± 0:20 h:min. Eighty-four percent of fetuses were born in anterior presentation (n = 16/19) and the final expulsion took <25 min suggesting that this is the normal presentation in white rhinoceros. In the less frequent posterior presentation final expulsion took up to 47 min. Overall, 95% of calves were born alive. Calves were standing and nursing in 0:55 ± 0:12 min and 3:32 ± 0:53 h:min, respectively. In 10.5% of births (n = 2/19) in anterior presentation perinatal complications occurred. Stillbirth occurred once (5.3% n = 1/19) when the foetus was born in posterior presentation. The recorded gestational length was 506 ± 2d. Delivering live offspring is of key importance to establish a new generation and secure long-term survival of a species. Various pre-birth changes, significant decrease of serum progesterone 48 h prior birth, different labour stages, foetal presentation and perinatal events described here add substantial knowledge on the understanding of normal rhinoceros parturition and may help diagnose dystocia and perinatal complications. • Parturition in captive rhinoceros is hard to predict and duration of different labour stages have yet not been described. • Gestational length and serum progesterone decline reliably predict parturition in rhinoceros. • Here, labour stages, foetal presentation and perinatal events describe the chronology of parturition in rhinoceros. • Data on parturition provides valuable information for obstetrical care and may reduce the stillbirth rate in captive rhinoceros. [ABSTRACT FROM AUTHOR]

This study aimed to address the lack of information on quantitative semen and sperm characteristics of free-ranging African elephants. Nineteen ejaculates were collected from 12 elephant bulls by means of electroejaculation in spring (Season 1, end of dry season, n = 7) and in autumn (Season 2, end of rainy season, n = 12). While most elephant cows are in oestrus in the rainy season, it is not evident whether sperm quality also improves during this period. Semen samples were assessed using computer-aided sperm analysis (CASA), brightfield microscopy and transmission electron microscopy. Seasonal differences and individual variation in sperm quality of bulls were apparent, with ejaculates collected during Season 2 revealing higher percentages for total motility, progressive motility, rapid-swimming spermatozoa and kinematic parameters compared with Season 1 (P < 0.05). Although normal sperm morphology percentage was similar over the two seasons, more sperm tail defects were found in Season 2 (P < 0.05). The baseline reference data and multivariate sperm parameter associations reported in this study can be used to predict elephant bull sperm quality and potential to fertilise. It is clear that CASA can detect subtle differences in sperm quality of African elephant ejaculates and should be the approach for future investigations. Comprehensive sperm functionality and morphometry characteristics were assessed by computer-aided sperm analysis hardware and software for the first time in free-ranging African elephants over two seasons. Sperm quality remains high throughout the year; however, during the rainy season most cows come into oestrus and sperm functionality parameters seem to peak over this period. Our data provide important baseline information for future studies. [ABSTRACT FROM AUTHOR]

The northern white rhinoceros (NWR, Ceratotherium simum cottoni) is the most endangered mammal in the world with only two females surviving. Here we adapt existing assisted reproduction techniques (ART) to fertilize Southern White Rhinoceros (SWR) oocytes with NWR spermatozoa. We show that rhinoceros oocytes can be repeatedly recovered from live SWR females by transrectal ovum pick-up, matured, fertilized by intracytoplasmic sperm injection and developed to the blastocyst stage in vitro. Next, we generate hybrid rhinoceros embryos in vitro using gametes of NWR and SWR. We also establish embryonic stem cell lines from the SWR blastocysts. Blastocysts are cryopreserved for later embryo transfer. Our results indicate that ART could be a viable strategy to rescue genes from the iconic, almost extinct, northern white rhinoceros and may also have broader impact if applied with similar success to other endangered large mammalian species. [ABSTRACT FROM AUTHOR]

In Europe, the yellow-bellied slider (Trachemys scripta sp.) is a non-native species in competition with native freshwater turtles. Research on contraception could be useful to control the captive population. Identifying a method of contraception in chelonians would potentially help to control aggression in other chelonian species. The objective of the current study was to evaluate the effects of a single 4.7-mg deslorelin acetate implant on plasma testosterone concentrations in yellow-bellied sliders (Trachemys scripta sp.). Eleven adult male yellow-bellied sliders were used for the study. Males from the treatment group (n = 6) received a 4.7-mg deslorelin acetate implant, whereas males from the control group (n = 5) did not receive any treatment. All individuals were housed under the same environmental conditions. Testosterone plasma concentrations of the control group and the treatment group were measured at six time points (T0–T6) between April and September. No difference between the control group and the deslorelin treatment group was observed at T0, T2, T3, T4, T5 or T6. However, mean plasma testosterone concentration was significantly higher in the treatment group than in the control group at T1. This suggests that treatment with a 4.7-mg deslorelin acetate implant has a transient stimulatory effect on the anterior pituitary in yellowbellied sliders without a negative feedback on testosterone production. Further studies with a higher dosage of deslorelin acetate are needed to draw conclusions on its contraceptive effect. [ABSTRACT FROM AUTHOR]

The olm (Proteus anguinus) is a troglomorphic, neotenous amphibian with extraordinary life expectancy and unique adaptations that deserve further investigation. A low reproductive rate and habitat decline render it threatened by extinction. Establishing captive populations for maintenance and artificial breeding may one day become crucial to the species. Longitudinal, in-vivo assessment of inner organs is invaluable to our understanding of reproductive physiology, health, and behavior. Using ultrasound, we measured heart rate and assessed health and reproductive status of 13 captive olms at Zagreb Zoo. Heart rate averaged 42.9 ± 4.6 bpm (32–55 bpm), as determined via pulsed-wave Doppler at 4–12 MHz. By using frequencies of up to 70 MHz (ultrasound biomicroscopy), inner organs were visualized in detail. Assessment of the gastrointestinal tract provided insights into feeding status and digestive processes. Several subclinical pathologies were detected, including biliary sludge, subcutaneous edema, ascites, and skin lesions. Detection of skin lesions by ultrasound was more sensitive than visual adspection. Olms with ultrasonographically detected skin lesions tested positive for Saprolegnia and were treated. Three of the four affected individuals survived and subsequently tested negative for Saprolegnia. Sex was reliably determined; only one individual proved male. The reason for this extreme female-biased sex-ratio remains unknown. However, as most of the individuals were flushed from the caves by strong currents in spring, the sample may not be representative of natural populations. In female olms, different stages of ovarian follicular development were observed with diameters ranging between 0.1 and 1.1 mm. Results were confirmed by comparing ultrasound, necropsy, and histological findings of one dead specimen. In summary, ultrasound proved a valuable tool to support conservation and captive breeding programs by allowing non-invasive assessment of physiological parameters, clinical condition, and reproductive status in olms. [ABSTRACT FROM AUTHOR]

In asses, semen collection, cryopreservation, and artificial insemination (AI) with frozen-thawed semen have been scarcely described and success rate, particularly following AI, is reportedly low. In the absence of reliable protocols, assisted reproductive technologies cannot support the conservation efforts aimed at endangered wild ass species and domestic donkey breeds. Two experiments were conducted in this study. In experiment 1 we evaluated freezing Abyssinian donkey (N = 5, 4 ejaculates each) spermatozoa using three freezing extenders (Berliner Cryomedium + glycerol, BC+G; BotuCrio, BOTU; INRAFreeze, INRA) and two cryopreservation techniques (liquid nitrogen vapour, LNV; directional freezing, DF). Post-thaw evaluation indicated that BOTU and INRA were similar and both superior to BC+G (P ≤ 0.004 for all motility tests), and that DF was superior to LNV (P < 0.002 for all evaluation parameters). In experiment 2, relying on these results, we used Abyssinian donkey sperm frozen in BOTU and INRA by DF for AI (N = 20). Prior to AI, thawed samples were diluted in corresponding centrifugation media or autologous seminal fluids at 1:1 ratio. No difference was found between BOTU and INRA or between the addition of seminal fluids or media, all resulting in ~50% pregnancy, and no differences were noted between males (N = 4). The size of pre-ovulatory follicle was a significant (P = 0.001) predictor for AI success with 9/10 pregnancies occurring when follicular size ranged between 33.1–37.4 mm, no pregnancy when it was smaller, and only one when larger. A number of ass species face the risk of extinction. Knowledge gained in this study on the Abyssinian donkey can be customised and transferred to its closely related endangered species and breeds. [ABSTRACT FROM AUTHOR]

This study investigated ways of improving the usefulness of,1700mL of poor-quality frozen semen collected from wild African elephant (Loxodonta africana) bulls. Ten semen samples from six bulls, frozen with 5% glycerol in Berliner cryomedium, with or without prior removal of the seminal plasma by centrifugation, were tested. All samples were subjected to the following density-gradient centrifugation treatments: no centrifugation (control), sham centrifugation, Percoll, OptiPrep, Isolate and PureSperm. Sample evaluation included motility, concentration, viability, acrosome integrity and normal morphology after thawing and after gradient centrifugation. Motility was also evaluated 3 h after thawing. While all treatments were similar to the Control in acrosome integrity and normal morphology, significant differences were noted in concentration, viability and motility. Samples treated by Percoll showed the best motility, which was maintained unchanged over 3 h of incubation (378C). Correlations between manual and automated evaluations of concentration were high (cytometer; rho=0.92), but were lower for viability (cytometer; rho=0.57) and motility (computer-aided sperm analysis; rho=0.66). By performing density centrifugation, the quality of these sperm samples may be improved to a level suitable for artificial insemination in elephants. Although a sizeable proportion of cells are lost in the process, combining samples may still allow for multiple inseminations. [ABSTRACT FROM AUTHOR]

With only three living individuals left on this planet, the northern white rhinoceros ( Ceratotherium simum cottoni) could be considered doomed for extinction. It might still be possible, however, to rescue the (sub)species by combining novel stem cell and assisted reproductive technologies. To discuss the various practical options available to us, we convened a multidisciplinary meeting under the name 'Conservation by Cellular Technologies.' The outcome of this meeting and the proposed road map that, if successfully implemented, would ultimately lead to a self-sustaining population of an extremely endangered species are outlined here. The ideas discussed here, while centered on the northern white rhinoceros, are equally applicable, after proper adjustments, to other mammals on the brink of extinction. Through implementation of these ideas we hope to establish the foundation for reversal of some of the effects of what has been termed the sixth mass extinction event in the history of Earth, and the first anthropogenic one. Zoo Biol. 35:280-292, 2016. © 2016 The Authors. Zoo Biology published by Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Epigenetic modifications, of which DNA methylation is the best studied one, can convey environmental information through generations via parental germ lines. Past studies have focused on the maternal transmission of epigenetic information to the offspring of isogenic mice and rats in response to external changes, whereas heterogeneous wild mammals as well as paternal epigenetic effects have been widely neglected. In most wild mammal species, males are the dispersing sex and have to cope with differing habitats and thermal changes. As temperature is a major environmental factor we investigated if genetically heterogeneous Wild guinea pig ( Cavia aperea) males can adapt epigenetically to an increase in temperature and if that response will be transmitted to the next generation(s). Five adult male guinea pigs (F0) were exposed to an increased ambient temperature for 2 months, i.e. the duration of spermatogenesis. We studied the liver (as the main thermoregulatory organ) of F0 fathers and F1 sons, and testes of F1 sons for paternal transmission of epigenetic modifications across generation(s). Reduced representation bisulphite sequencing revealed shared differentially methylated regions in annotated areas between F0 livers before and after heat treatment, and their sons' livers and testes, which indicated a general response with ecological relevance. Thus, paternal exposure to a temporally limited increased ambient temperature led to an 'immediate' and 'heritable' epigenetic response that may even be transmitted to the F2 generation. In the context of globally rising temperatures epigenetic mechanisms may become increasingly relevant for the survival of species. [ABSTRACT FROM AUTHOR]

The article offers information on a study on cryopreservation of epididymal spermatozoa of onager. Topics discussed include improvement in the genetic diversity of onager, increased sperm motility in samples stored in cold temperature, presence of heat shock proteins (HSP) in ejaculated sperms of mammals, no effect in acrosome integrity due to freezing and transportation variations, and benefits of directional freezing (DF) for preservation of semen for artificial insemination.

Currently, radiography is the only imaging technique used to diagnose bone pathology in wild animals situated under “field conditions”. Nevertheless, while chronic foot disease in captive mega-herbivores is widely reported, foot radiographic imaging is confronted with scarcity of studies. Numerous hindrances lead to such limited numbers and it became very clear that the traditional perspective on bone imaging in domestic animals based on extensive studies and elaborated statistical evaluations cannot be extrapolated to their non-domestic relatives. For these reasons, the authors initiated a multi-modality imaging study and established a pioneering approach of synchronized computed tomography (CT) and digital radiography (DR), based on X-ray projections derived from three-dimensional CT reconstructed images. Whereas this approach can be applied in any clinical field, as a case of outstanding importance and great concern for zoological institutions, we selected foot bone pathologies in captive rhinoceroses to demonstrate the manifold applications of the method. Several advances were achieved, endowing the wildlife clinician with all-important tools: prototype DR exposure protocols and a modus operandi for foot positioning, advancing both traditional projections and, for the first-time, species-related radiographic views; assessment of radiographic diagnostic value for the whole foot and, in premiere, for each autopodial bone; together with additional insights into radiographic appearance of bone anatomy and pathology with a unique, simultaneous CT-DR correlation. Based on its main advantages in availing a wide range of keystone data in wildlife imaging from a limited number of examined subjects and combining advantages of CT as the golden standard method for bone diseases' diagnostic with DR's clinical feasibility under field conditions, synchronized CT-DR presents a new perspective on wildlife's health management. With this we hope to provide veterinary clinicians with concrete imaging techniques and substantial diagnostic tools, which facilitate straightforward attainment and interpretation of field radiography images taken worldwide. [ABSTRACT FROM AUTHOR]

In Indian rhinoceros, extensive leiomyoma, a benign smooth muscle tumour, was sporadically diagnosed post mortem and commonly thought of as contributing factor for reduced fecundity of this species in captivity. However, to date, the prevalence of reproductive tract tumours and their relevance for fecundity are unknown. Our analysis of the international studbook now reveals that females cease reproducing at the age of 18.1±1.2 years; equivalent to a reproductive lifespan of just 9.5±1.3 years. This short reproductive life is in sharp contrast to their longevity in captivity of over 40 years. Here we show, after examining 42% of the captive female population, that age-related genital tract tumours are highly prevalent in this endangered species. Growth and development of these tumours was found to be age-related, starting from the age of 10 years. All females older than 12 years had developed genital tumours, just 7–9 years past maturity. Tumour sizes ranged from 1.5–10 cm. With age, tumours became more numerous, sometimes merging into one large diffuse tumour mass. These tumours, primarily vaginal and cervical, presumably cause widespread young-age infertility by the age of 18 years. In few cases, tumour necrosis suggested possible malignancy of tumours. Possible consequences of such genital tract tumour infestation are hindered intromission, pain during mating, hampered sperm passage, risk of ascending infection during pregnancy, dystocia, or chronic vaginal bleeding. In humans, leiomyoma affect up to 80% of pre-menopause women. While a leading cause for infertility, pregnancy is known to reduce the risk of tumour development. However, different from human, surgical intervention is not a viable treatment option in rhinoceroses. Thus, in analogy to humans, we suggest early onset and seamless consecutive pregnancies to help reduce prevalence of this disease, better maintain a self-sustained captive population and improve animal welfare. [ABSTRACT FROM AUTHOR]

Background: The captive elephant population is not self-sustaining and with a limited number of breeding bulls, its genetic diversity is in decline. One way to overcome this is to import young and healthy animals from the wild. We introduce here a more sustainable alternative method - importation of semen from wild bulls without removing them from their natural habitat. Due to the logistics involved, the only practical option would be to transport cryopreserved sperm. Despite some early reports on African elephant semen cryopreservation, the utility of this new population management tool has not been evaluated. Methodology/Principal Findings: Semen was collected by electroejaculation from 14 wild African savanna elephant (Loxodonta africana) bulls and cryopreserved using the directional freezing technique. Sperm treatments evaluated included the need for centrifugation, the use of hen or quail yolk, the concentration of glycerol (3%, 5% or 7%) in the extender, and maintenance of motility over time after thawing. Our results suggest that dilution in an extender containing hen yolk and 7% glycerol after centrifugation best preserved post-thaw sperm motility when compared to all other treatments (P≤0.012 for all). Using this approach we were able to achieve after thawing (mean ± SD) 54.6±3.9% motility, 85.3±2.4% acrosome integrity, and 86.8±4.6% normal morphology with no decrease in motility over 1 h incubation at 37°C. Sperm cryopreserved during this study has already lead to a pregnancy of a captive female elephant following artificial insemination. Conclusions/Significance: With working techniques for artificial insemination and sperm cryopreservation of both African and Asian elephants in hand, population managers can now enrich captive or isolated wild elephant populations without removing valuable individuals from their natural habitat. [ABSTRACT FROM AUTHOR]

Lynx presents a unique sexual cycle with persistent corpora lutea (CLs) and elevated serum progesterone (P4) throughout parturition and lactation. In other mammals, CLs normally disintegrate after parturition, therefore the aim of our studywas to characterise the annual life cycle of lynx CLs. Ovaries from Eurasian lynxes were obtained from the National Veterinary Institute in Sweden, where tissues from killed lynx were stored at -20 °C. Ovaries from 66 animals were weighed; each corpus luteum was segmented for histology and hormone analysis. Ovary and CLs weights were constant throughout the year, peaking during pregnancy. In non-pregnant lynxes, the seasonal level of intraluteal steroids was steady for P4 (3.2±1.9 S.D. mg/g, nZ53) and total oestrogens (18.3±15.5 S.D. ng/g, nZ53). Within histology slides, structurally intact luteal cells were found throughout the year with the highest incidence in March/April; evidence of luteal regression was predominantly found in post-breeding season. Ovaries from pregnant animals contained two types of CLs. Group A was bigger in size with large luteal cells (P4, 72.3±65.4 S.D. mg/g; oestrogen, 454.0±52.4 S.D. ng/g). In contrast, group B were smaller, with greater luteal regression and lower steroid concentrations (P4, 8.3±2.9 S.D. mg/g; oestrogen, 31.5±20.4 S.D. ng/g). Our results suggest that structural luteolysis proceeds throughout the year and into next breeding cycle, resulting in two CLs types on the same ovary. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the two anesthetic procedures and immobilization performed on a 15-year-old adult male Sumatran rhinoceros (Dicerorhinus Sumatrensis) in Malaysia. It states that the immobilization and anesthetic procedures, which include monitoring of heart rate (HR) and evaluation of respiratory rate (RR), is done for the collection of semen and examination of its bilateral corneal capacities. The result of the study shows that the procedures particularly the use of the combination of detomidine and butorphanol serves a satisfactory anesthesia for the captivity management of the animals. It adds that the blood gas analysis shows respiratory acidosis with hypoxemia and hypercapnea while the hemoglobin oxygen saturation (SPO2) is low.

Abstract: This study characterized (in vivo) morphological and functional parameters of reproductive organs of adult male lynx (n =3) prior to, during, and after the breeding season (n =3). Size and morphology of the reproductive tract were monitored by transcutaneous (testes) and transrectal (accessory sex glands) ultrasonography. Semen was collected by electroejaculation. Ejaculate volume, sperm number, motility, and morphology of spermatozoa as well as testosterone concentrations in blood serum and feces were evaluated. The testes and prostate had seasonal changes in size and echotexture. The mean (±S.D.) maximum and minimum testicular volume were 2.8±0.8cm3 and 1.5±0.3cm3, respectively. Fecal testosterone concentrations were highest in February (1240±393ng/g feces), with a second increase in May (971±202ng/g feces), but concentrations were lowest in January (481±52.9ng/g feces). Ejaculate volume, total sperm number and percentage of motile, and intact spermatozoa were maximal in March (the middle of the breeding season). In one of the eight litters, multiple paternity was proven; however, in the remaining seven litters, all 16 cubs were sired by the same male. This particular male had the most developed and active testes and best semen quality, which may be important for sperm competition. [Copyright &y& Elsevier]

Growth factors are involved in the regulation of testicular growth and involution of seasonal breeders. Therefore, we studied the seasonal expression of several growth factors in roe deer: aFGF, bFGF, IGF-1, IGF-2, and TGF-α. Total RNA from testis tissue was extracted monthly and analyzed using quantitative RT-PCR. Localization of mRNAs was examined by in situ-hybridization. Levels of expression differed by more than three orders of magnitude. Expression also showed different seasonal patterns. IGF-1, IGF-2 and bFGF were maximally transcribed during testis recrudescence in spring. In contrast, the mRNA amount of aFGF reached its maximum between July (breeding season) and January. TGF-α mRNA-levels were very low and showed poor seasonal variation. Each growth factor showed its own typical expression localization in testicular tissues and cell types. The results suggest the specific role of different growth factors in the paracrine control of spermatogenesis and its seasonal regulation. [ABSTRACT FROM AUTHOR]

Simple Summary: Efficient collection and cryosurvival of semen from threatened wildlife species is key for the success of artificial reproductive technologies (ARTs). The viscous nature of ejaculates often collected from species such as rhinoceros, elephant, hippopotamus and primate, render the majority of spermatozoa collected useless and is therefore wasted. The enzyme papain has been used to reduce the viscosity of camelid semen but has yet to be tested in wildlife species. Therefore, the current study investigated the ability of papain to improve the yield and quality of spermatozoa collected from viscous fractions of the rhinoceros ejaculate during cryopreservation. Papain increased the quantity of useable spermatozoa collected from ejaculates, as well as the motility prior to freezing. It also improved the post-thaw motility, velocity, linearity and straightness of samples compared to spermatozoa frozen from the sperm-rich fraction of the ejaculate. There was no detrimental effect on membrane characteristics or DNA integrity. These results show that treating rhinoceros ejaculates with papain is able to salvage valuable spermatozoa and improve survival post-thaw, ultimately increasing the success of ARTs and creation of biobanks for the maintenance and survival of threatened species. The preservation of rhinoceros semen is vital for captive breeding programs. While successful collection and cryopreservation of rhinoceros semen has been reported, the volume and quality of semen produced is often low due to the high viscosity associated with ejaculates collected via electroejaculation. Reducing semen viscosity would enable access to previously unusable spermatozoa from viscous fractions and could improve quality post-thaw. The enzyme papain successfully reduced the viscosity of camelid semen but has yet to be tested in wildlife species. This study assessed the influence of papain on the in vitro quality of rhinoceros spermatozoa during cryopreservation using advanced semen assessment. In experiment 1, the motility of spermatozoa from the viscous fraction of an ejaculate, either untreated or treated with papain and its inhibitor E-64 prior to cryopreservation, was assessed post-thaw. In experiment 2, spermatozoa from papain-treated viscous fractions were compared to spermatozoa frozen from untreated sperm-rich fractions pre-freeze, as well as after 0, 1.5 and 3 h of incubation post-thaw (37 °C). Papain significantly increased the quantity of spermatozoa collected from ejaculates, as well as the motility prior to freezing. Papain also improved the post-thaw motility, velocity, linearity and straightness of samples compared to sperm-rich samples, with no detriment to sperm viability, lipid membrane disorder, production of ROS or DNA integrity (p < 0.05). Results show the benefit of supplementing rhinoceros spermatozoa with papain prior to cryopreservation on sperm cryosurvival and demonstrates the potential of using papain to improve the success of cryopreservation protocols, not only for the rhinoceros, but also for other wildlife species. [ABSTRACT FROM AUTHOR]

Simple Summary: Applying assisted reproductive technologies (ARTs) to the conservation of endangered species may be the only way to save them from extinction. However, ART application can raise relevant ethical issues and could benefit from a comprehensive ethical assessment. Unfortunately, there is a lack of attention to the topic in the scientific literature and, to our knowledge, there is no tool for the ethical assessment of ARTs in the context of conservation that has been described. In the present paper, we show the effects of applying a dedicated ethical self-assessment tool, the Ethical Assessment Tool (ETHAS), to ovum pick-up and in vitro fertilization procedures performed within the BioRescue project. The BioRescue project is an international enterprise using ARTs to save the northern white rhinoceros from extinction. The situation of the northern white rhinoceros is particularly critical as there are only two individuals of this subspecies still alive and they are both infertile females. The application of the ETHAS to the procedures contributed to the overall acceptability of the project and improved communication among the project's partners. In turn, the tool itself was also refined through an iterative consultation process between experts (both ethicists and scientists) and stakeholders. Assisted reproductive technologies (ARTs) can make a difference in biodiversity conservation. Their application, however, can create risks and raise ethical issues that need addressing. Unfortunately, there is a lack of attention to the topic in the scientific literature and, to our knowledge, there is no tool for the ethical assessment of ARTs in the context of conservation that has been described. This paper reports the first applications of the Ethical Assessment Tool (ETHAS) to trans-rectal ovum pick-up (OPU) and in vitro fertilization (IVF) procedures used in a northern white rhinoceros (Ceratotherium simum cottoni) conservation project. The ETHAS consists of two checklists, the Ethical Evaluation Sheet and the Ethical Risk Assessment, and is specifically customized for each ART procedure. It provides an integrated, multilevel and standardized self-assessment of the procedure under scrutiny, generating an ethical acceptability ranking (totally, partially, not acceptable) and a risk rank (low, medium, high), and, hence, allows for implementing measures to address or manage issues beforehand. The application of the ETHAS to the procedures performed on the northern white rhinoceros was effective in ensuring a high standard of procedures, contributing to the acceptability and improved communication among the project's partners. In turn, the tool itself was also refined through an iterative consultation process between experts and stakeholders. [ABSTRACT FROM AUTHOR]

Bats, the second-largest mammalian order, are widely distributed and provide crucial ecosystem services. Their reproductive biology comprises noteworthy characteristics, such as long-term sperm storage, delayed implantation or even delayed fetal development. The understanding of these mechanisms remains limited. Research in reproductive biology may become crucial for the conservation of endangered bat species. Indeed, the IUCN Red List of Threatened Species currently lists 76 bat species as endangered or critically endangered, for which conservation measures should be taken. The development of assisted reproductive technologies (ART) in bats would thus open new perspectives. In this context we here describe the first successful cryopreservation of bat sperm in the Seba's short-tailed bat (Carollia perspicillata). Epididymal sperm of 30 males was pooled in 6 sample sets and diluted using four different cryo-diluents: Canifreeze, modified Canifreeze, BotuCrio® and Test egg yolk extender. Glycerol and a mixture of glycerol and methylformamide were used as cryoprotectants. Best post-thaw results were achieved when sperm was diluted in Test egg yolk extender containing a mixture of glycerol and methylformamide as cryoprotectant. Post-thaw sperm motility, progressive motility and acrosome integrity of 42.0 ± 3.4%, 28.3 ± 6.3% and 87.7 ± 1.7%, respectively were superior to all other variants tested. It remains to be determined if the post-thaw quality of cryopreserved bat spermatozoa achieved in this study is sufficient for the use in artificial inseminations and produces acceptable pregnancy rates. Successful cryopreservation of spermatozoa in C. perspicillata may serve as the first model to establish gamete rescue programs and develop ART in other, critically endangered bat species. • This is the first report on bat sperm cryopreservation, the first in this order of mammals. • Test-egg-yolk diluent containing a mixture glycerol/methylformamide produced post thaw sperm motility of 42.0 ± 3.4%. • Cryoprotectants: A mixture of glycerol/methylformamide was significantly superior to glycerol alone as cryoprotectant. • Cryopreservation of Seba's short-tailed bat may serve as model for gamete rescue in other endangered bat species. [ABSTRACT FROM AUTHOR]

Genome Resources Banks (GRBs) represent vital repositories for the systematic collection, storage, and management of genetic material across various taxa, with a primary objective of safeguarding genetic diversity for research and practical applications. Alongside the development of assisted reproductive techniques (ART), GRBs have evolved into indispensable tools in conservation, offering opportunities for species preservation, mitigating inbreeding risks, and facilitating genetic management across fragmented populations. By preserving genetic information in a suspended state, GRBs serve as backups against population vulnerabilities, potentially aiding in the restoration of endangered species and extending their genetic lifespan. While evidence demonstrates the efficacy of GRBs, ethical considerations surrounding biobanking procedures for wildlife conservation remain largely unexplored. In this article, we will discuss possible ethical issues related to GRBs and the need to ethically monitor biobanking procedures in wildlife conservation. We will then propose a methodological tool, ETHAS, already in use for the ethical self-assessment of assisted reproduction techniques, to assess also biobanking procedures. ETHAS can make it possible to monitor a GRB from its design phase to its actual operation, helping to build biobanking procedures that meet high ethical standards. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Adult roe deer males show seasonal cycles of testicular growth and involution. The exact timing of these cycles requires endocrine regulation and local testicular control by autocrine/paracrine factors. Recent findings suggest that the vascular endothelial growth factor (VEGF) might have effects on both vascular and germinative cells in testis. Thus, we studied the expression pattern of vascular endothelial growth factor (VEGF) in roe deer testis using quantitative RT-PCR. The strength of VEGF mRNA expression depended on season. It reached its highest level at the peak of spermatogenesis during the pre-rutting period and had its nadir at the end of the rut when involution already began. The results suggested that VEGF may directly affect the regulation of spermatogenesis but may not be involved predominantly in testicular microvasculature as initially expected. [Copyright &y& Elsevier]

Abstract: Sex allocation theories predict equal offspring number of both sexes unless differential investment is required or some competition exists. Left undisturbed, elephants reproduce well and in approximately even numbers in the wild. We report an excess of males are born and substantial juvenile mortality occurs, perinatally, in captivity. Studbook data on captive births (CB, n =487) and premature deaths (PD, <5 years of age; n =164) in Asian and African elephants in Europe and North America were compared with data on Myanmar timber (Asian) elephants (CB, n =3070; PD, n =738). Growth in CB was found in three of the captive populations. A significant excess of male births occurred in European Asian elephants (ratio: 0.61, P =0.044) and in births following artificial insemination (0.83, P =0.003), and a numerical inclination in North American African elephants (0.6). While juvenile mortality in European African and Myanmar populations was 21–23%, it was almost double (40–45%) in all other captive populations. In zoo populations, 68–91% of PD were within 1 month of birth with stillbirth and infanticide being major causes. In Myanmar, 62% of juvenile deaths were at >6 months with maternal insufficient milk production, natural hazards and accidents being the main causes. European Asian and Myanmar elephants PD was biased towards males (0.71, P =0.024 and 0.56, P <0.001, respectively). The skewed birth sex ratio and high juvenile mortality hinder efforts to help captive populations become self-sustaining. Efforts should be invested to identify the mechanism behind these trends and seek solutions for them. [Copyright &y& Elsevier]

The application of Assisted Reproductive Technologies (ART) in breeding programs to save wild animal species is a relatively new approach to conservation and their ethical implications seem still to be underestimated. However, the ethical evaluation is a decisive step for conservation projects employing ART to address crucial questions like the welfare and life of the animals involved, the survival of the targeted species, the quality and safety of the procedures and the very idea of biodiversity conservation we want to pursue. Balancing the potential benefits of ART with the risks involved requires careful ethical analysis. This paper highlights the increasing role of ART in species conservation and emphasizes the need to address their ethical implications. After discussing the lack of ethical discussion in ART application to wildlife, the contribution outlines an ethical frame to address this gap and introduces an ETHical ASsessment tool (ETHAS) for the ethical self-assessment of ART procedures in vertebrate conservation. The tool allows respondents to highlight ethical aspects to be improved and risks related to the procedure, from its design to each application. The ethical approach to the ART application, relatively novel to wildlife conservation, can contribute to assure the ethical acceptability of conservation programs while favoring discussion and communication among project partners and the integration of ethical aspects in conservation programs. [Display omitted] • Ethical implications of assisted reproduction technologies are still underestimated. • Several ethical aspects should be considered in ARTs application in conservation. • Ethical assessment guarantees project's ethical acceptability and high standards. • Ethical self-assessment highlights ethical aspects to be improved, reducing risks. • Ethical self-assessment promotes communication and inclusive decision-making. [ABSTRACT FROM AUTHOR]

Abstract: There is an increasing demand for management of feral and wild carnivores; since many of them have become “pest species” by adapting successfully to changing environments, having substantial impacts on their prey species, and serving as reservoirs for infectious diseases. Also in captivity, a low adult mortality and an increase in longevity, especially in large carnivores, cause an urgent need for population management. This paper presents an overview on contraceptive strategies to control reproduction in carnivores. Factors that have to be considered before applying a certain method for fertility suppression are discussed. For birth control, several methods of hormonal chemosterilization, immunocontraception and pregnancy termination have been developed in domestic and captive exotic carnivores, but none of them are yet suitable for free-ranging animals. GnRH agonists, which suppress pituitary function very efficiently, are recommended in captive and domestic animals for reversible contraception. Immunological contraception, causing prolonged infertility after single application, is a promising approach for feral animals. However, a specific gamete or hormone-derived “self” antigen must be identified for each particular species. [Copyright &y& Elsevier]

Abstract: White rhinoceroses suffer from a low reproductive rate in captivity. Intensive efforts to propagate specifically the northern white rhinoceros have been very limited. The dismal outlook for this subspecies in the wild makes successful ex situ breeding programs paramount. In this context, this study examined 48 southern and 6 northern white rhinoceroses using ultrasound and faecal hormone analysis to elucidate causes for female reproductive failure and to determine whether long non-reproductive periods have a detrimental impact on genital health. Results showed that 76% of the nulliparous females had intact hymenal membrane indicating these females had never been bred, at an age when their wild counterparts have delivered multiple offspring. Fifty-six percent of the studied population had various reproductive pathology. Cystic endometrial hyperplasia; leiomyomas of the cervix, uterus and ovary, adenoma; para-ovarian cysts and hydromucometra represent the scope of lesions identified. The stages of the lesions in nulliparous females correlated with age (r =0.4, P <0.05). Due to the severity of the lesions, 28% of the study population was considered post-reproductive. Therefore, the reproductive life span in some individuals was 10–20 years shorter than expected. However, in parous females the incidence of pathological lesions was significantly lower (P <0.0001). Seventy-eight percent females studied had erratic or absent luteal activity. The hormone data corresponded with two ultrasonographic levels of ovarian activity, active and inactive, occurring within an age range of 3–19 years and 15–38 years, respectively. This suggests the lack of ovarian activity by reproductive mid-life in non-reproducing females. The accuracy of the ultrasound findings was validated by necropsy in nine animals showing a strong positive correlation (r 2 =0.9, p <0.001). Our data suggests that the development of reproductive pathology and ovarian inactivity in white rhinoceros is an age-related consequence of long non-reproductive periods. This asymmetric ageing process of the genital organs can be prevented with the achievement of at least one pregnancy. [Copyright &y& Elsevier]

White rhinoceroses suffer from a low rate of reproduction in captivity. This study examines the role of male reproductive function as a contributing factor. We used ultrasonography to image accessory sex glands, testis and epididymis. Electroejaculation provided 36 ejaculates from 21 rhinoceroses. Based on the percentage of progressively motile spermatozoa, semen was categorized in three groups, high (I: >75%), intermediate (II: 50–70%) or low (III: <50%) quality. Only 52% of the males showed high semen quality. Ejaculates in the high motility category also had the highest proportion of morphologically intact spermatozoa. Both semen parameters, sperm motility and morphology, were found to positively correlate with size of the accessory sex glands. The semen category was associated with group size suggesting that the social status influenced functional reproductive parameters. Change of territorial status (n = 1) improved semen quality. Testicular fibrosis was characterized as a sign of reproductive ageing in all males older than 15 years of age (n = 13); although, this ageing process did not notably affect semen parameters. Furthermore, for the benefit of assisted-reproduction and genetic banking programs protocols for the storage of cooled semen and the cryopreservation of spermatozoa were designed using different cryodiluents. This report provides basic data for the evaluation of reproductive components and of breeding management in male rhinoceros. Our results indicate that low rate of reproduction in captivity can be attributed to reduced male reproductive fitness. Changes in management of white rhinoceroses may positively affect male reproductive function. [Copyright &y& Elsevier]