Short-term preservation of canine sperm-binding ability and other metrics using the INRA-96 in comparison to Tris-egg yolk extender

The use of assisted reproductive techniques, such as chilled semen, contributes to the maintenance and genetic improvement of canine breeding. The INRA-96 extender is a commercially available, chemically defined medium that was initially developed for the preservation of equine semen and exhibits preservation potential in the canine species. This research aims to evaluate the INRA-96 extender as an alternative for the short-term preservation of canine semen in terms of sperm quality parameters such as motility and kinetic parameters, integrity and functionality of the plasma membrane in fresh and chilled-rewarmed samples, as well as the sperm-binding ability using the perivitelline membrane of the chicken egg as an indicator of the fertilizing capacity of the preserved semen. A total of 18 ejaculates from 9 French bulldogs (two ejaculates per dog) were collected and divided into two aliquots that were diluted in Tris-egg yolk 20% (control) or INRA-96 to a final concentration of 100 × 106 sperm/mL. Samples were refrigerated in a biological incubator at 5°C and evaluated at 0, 24 and 48 h time points. Comparing the two treatments after 48 h of refrigeration, both extenders showed similar values (p < .5) for the majority of kinetic parameters, with the INRA-96 group promoting a total motility of 88.1 ± 2.9%. In addition, the morphology, integrity and functionality of the plasma membrane were preserved above 70% in this group. Dilution with INRA-96 also provided a significantly higher amount of sperm bound (256.2 ± 21.1) to the perivitelline membrane of the egg yolk compared to the sperm-binding rates (p < .05) achieved at the use of Tris-egg yolk (215.2 ± 21 bound spermatozoa) at 48 h. Our study proved similar functional properties of dog sperm cells treated with INRA-96 in comparison to commonly used home-made Tris-based extender during short-time storage.

Association between anti-Müllerian hormone levels and reproductive parameters in Wagyu cattle raised in Brazil

The production of in vitro embryos has sped up the dissemination of superior genetic material. However, the variation among the cattle response to oocyte and embryo production is a challenging factor. This variation is even higher in the Wagyu cattle as the breed has a small effective population size. The identification of an effective marker related to reproductive efficiency would allow the selection of more responsive females to reproductive protocols. The objective of this study was to evaluate the blood levels of anti-Müllerian hormone and associate it with oocyte recovery and blastocyst rate of embryos produced in vitro in Wagyu cows, as well as observe the hormone circulating levels in males. Serum samples from 29 females with seven follicular aspirations and four bulls were used. AMH measurements were performed using the bovine AMH ELISA kit. A positive correlation was identified between oocyte production and blastocyst rate (r = 0.84, P = 9 × 10^-9), and AMH levels with oocyte (r = 0.49, P = 0.006) and embryo (r = 0.39, P = 0.03) production. The mean levels of AMH were different between animals with low (11.06 ± 3.01) and high (20.75 ± 4.46) oocyte production (P = 0.01). Males showed high serological levels of AMH (3829 ± 2328 pg/ml) compared with other breeds. It is possible to use the serological measurement of AMH as a method to select Wagyu females with greater capacity for oocyte and embryo production. Further studies correlating AMH serological levels with Sertoli cell function in bulls are needed.

Cryopreservation of jaguar (Panthera onca) sperm cells using different cryoprotectants and different thawing temperatures

The cryopreservation of jaguar semen must be improved to produce high-quality biobanking doses. Until now, the rare studies of semen freezing in the species have only evaluated glycerol, always with a significant reduction in sperm quality in thawed semen. The purpose of this study was to assess the efficacy of three cryoprotectants, dimethylsulfoxide (DMSO), glycerol (GLY), and methanol (MET), in the cryopreservation of jaguar semen in an LDL-based extender, as well as the effect of thawing temperature on dosage quality. Five mature males with a history of reproduction were used. On the males, an infrared thermal image (IRT) was captured, the spicules and testes were analyzed, and the CASA system was used to evaluate the quality of fresh and thawed sperm. The superficial IRT was 4.6 ± 1.2 °C cooler than the anal sphincter, and the semen measured between 27.3 and 28.7 °C shortly after exiting the urethra. The total motility of fresh sperm was 55.3 ± 22.6%, and progressive motility was 36.3 ± 18%. The total motility of thawed sperm was 5.28 ± 2.51%, 4.49 ± %2.49, and 0.51 ± 0.62% for DMSO, GLY, and MET, respectively. DMSO and GLY performed better than MET, and there was no difference in thawing temperature (37°C 30 s vs. 50°C 12 s). All animals exhibit a considerable level of morphological changes in sperm. Low amounts of total and progressive motility were found in the thawed sperm. Males with a high level of sperm morphological changes were found to be fertile, but the lone male with normospermia was infertile. Thus, we contest the applicability of the commonly used morphological classification for bovines to felid species.

Surgical sterilization of free-ranging capybaras (Hydrochoerus hydrochaeris): “Passos Nunes” uterine horn ligature

Capybaras are the primary hosts of Amblyomma sculptum tick, vectors of Rickettsia rickettsia bacteria, and the zoonotic agent of Brazilian Spotted Fever (BSF). In this context, contraceptive methods have been suggested for population control in order to reduce the number of free-ranging capybaras cohabiting with humans in urban and rural areas and acting as disease amplifiers. To maintain the group's expected behavior and social hierarchy, sterilization techniques that preserve the gonads are recommended. On 126 female capybaras in the Brazilian state of São Paulo, a new surgical technique named “Passos Nunes” uterine horn ligature was performed after adequate general anesthesia. It achieved effective surgical sterilization, with an incision length of about 3 cm in the periumbilical linea alba, cranial to the pubis. After entering the abdominal cavity, the urinary bladder is pulled laterally to access the uterine horns and the cervix. The uterine horn is folded up, forming a strap; the distal portion of the strap is ligated and its distal end sectioned. The exact process is performed on the opposite horn. After the surgical procedure, the musculature is sutured in a sultan pattern and the subcutaneous tissue with a horizontal mattress pattern. The skin is sutured in a separate simple format, using nylon 2.0 for all steps. The wide exposure of the uterine horns facilitates the confirmation of pregnancy, allowing the surgeon to choose between salpingo hysterectomy or ligature of the uterine horns. The present study presents a new technique of surgical sterilization that can be used in female free-ranging mammals in which maintenance of the gonads is recommended, and births of offspring should not occur.

Can detomidine replace medetomidine for pharmacological semen collection in domestic cats?

Among the different methods used for semen collection from domestic cats, the pharmacological collection by urethral catheterization becomes disruptive. Medetomidine is the elected α²-adrenoceptor agonist for that, but in several countries, it is not commercially available. This study aimed to evaluate the efficacy of detomidine compared to medetomidine in collecting semen by urethral catheterization in domestic cats. Urethral catheterization was performed on 13 mongrel cats using a disposable semi-rigid tomcat urinary catheter. Of the 19 semen collections performed with medetomidine induction, 94.7% were successful, while with detomidine induction, only 56.3% of 16 were successful. The values semen samples variables were as follows for volume - 10.56 ± 0.4 vs 8.88 ± 0.5 mL, motility - 171.67 ± 0.79 vs 49.77 ± 3.45%, vigor - 4.1 ± 0.03 vs 3.10 ± 0.1 and concentration - 3.24 ± 0.19 vs 2.15 ± 0.13 ×10⁹ sperm/mL respectively for medetomidine and detomidine group. The failure in semen collections with detomidine was mainly due to azoospermic samples, poor urethral relaxation, insufficient volume, or contamination of urine. The sperm concentration was also lower in the detomidine group (P <0.05) when compared to medetomidine. However, when the volume of semen collected was compared, we found no statistical differences. Despite its low performance in collecting semen from cats, detomidine may be an alternative when medetomidine is not accessible.

One Conservation: the integrated view of biodiversity conservation

The current global situation requires urgent decision-making to reverse processes of mass extinction of thousands of species. As a way of showing the importance of joint actions in this process, we aim to present the concept of One Conservation as a new proposal for the integration of sustainability, in situ and ex situ conservation for the restoration of ecosystems. According to the United Nations, we are beginning the decade of ecosystem restoration and in association with the International Union for Conservation of Nature guidelines, we can join efforts in the conservation of the planet. The survival of many species of wild animals depends on the management of populations currently maintained in ex situ conditions (under human care). To facilitate the exchange of genetic material between in situ and ex situ populations, reproductive biotechniques have become a great tool, making it possible to restore species in their natural environments. For effective conservation to occur, there must be an integrated view of the problem as a whole, and action for solutions must take place jointly by different spheres of society. Even more, conservation must be carried out by the public sector, the private sector, the third sector, and not less importantly, the agricultural sector. Therefore, One Conservation is defined as an interconnection between ex situ and in situ conservation plans, anthropic actions in the environment, and research in different areas that encompass conservation.

Spermatic profile of captive giant anteaters (Myrmecophaga tridactyla): Knowing more to preserve better

The giant anteater (Myrmecophaga tridactyla) is being threatened by natural habitat destruction and fragmentation, illegal hunting and road kills. In this context, the generation of basic information on the reproductive parameters of this species is vital, aiming to improve reproductive management via, amongst others, assisted reproductive technologies. This study aimed to describe the morphological and functional features of semen collected from captive giant anteaters. Electroejaculation was performed in 13 animals housed in zoos located in São Paulo state, Brazil. Semen samples were collected from 13 animals in 16 procedures. Samples were evaluated for volume, motility, vigor, pH, concentration, sperm morphology, and functional tests. The following mean values were obtained: volume 1.28 ± 0.27 mL; motility 28.3 ± 6.2%; vigor 2.4 ± 0.25; concentration 129.4 ± 36.1 × 10⁶ sperm/mL; pH 7.4 ± 0.2. Total acrosome, head, midpiece, and tail sperm abnormalities were 3.2 ± 0.8%, 25.4 ± 3.6%, 20.7 ± 3.2%, and 14.7 ± 2.6%, respectively. Intact acrosome was found in 83.7 ± 3.1% and intact membrane in 81.1 ± 4.0% of all samples collected. Mitochondrial activity was 66.4 ± 6.0% (Class I), 18.7 ± 2.9% (Class II), 8.0 ± 2.0% (Class III), 3.9 ± 1.0% (Class IV), and 3.0 ± 0.9% (Class V). Sperm DNA fragmentation rate was 13.2 ± 3.7%. These results indicated that electroejaculation is a feasible method for semen collection in giant anteaters, allowing a more detailed description of the semen in this species.

Cryptorchidism in free-living jaguar (Panthera onca): first case report

Cryptorchidism is a genital alteration wherein one or both testicles fail to descend into the scrotum and has multifactorial causes. A free-range adult male was captured twice in the Pantanal of Nhecolândia to put a GPS collar and semen collection. Pharmacological semen collection, andrological examination and semen analysis were performed. At the first capture and during the andrological examination only the left testis was found, and the male qualified as cryptorchid. The penis had no penile spines at either procedure. The semen volume obtained at first and second capture was 435 and 160 μL, respectively, with a concentration of 618 and 100 x 10⁶ sperm/mL, progressive motility of ~ 5% and ~ 1% and total morphological sperm abnormalities of 74% and 86%. The male was monitored by a GPS collar, but the signal was lost, making it difficult to re-captures and perform new seminal and ultrasound evaluations to discard monorchidism - exceedingly rare in felids. Genetic studies to assess the individual's homozygosity are necessary to verify whether cryptorchidism in this individual has a genetic factor.

Medetomidine may cause heart murmur in Cougars and Jaguars: case report

We report heart murmur in Jaguars and Cougars found during reproductive procedures for semen and oocyte collection.  Two male Cougars (n=2) and three female Jaguars (n=3) were examined.  Anesthesia was performed with ketamine and medetomidine in males.  Females also received propofol and were maintained with isoflurane.  The animals were evaluated during anesthetic monitoring with multiparameter monitor alongside clinical examination, ambulatory electrocardiogram and echocardiogram.  All animals presented mitral valve regurgitation under anesthesia, but without morphological changes in the cardiac structure or hemodynamic changes.  Medetomidine may cause transitory heart murmur in healthy Jaguars and Cougars.   

Sperm evaluation and morphological description of male genitalia of meerkats (Suricata suricatta)

In ex situ conditions, little is known about the reproductive biology of meerkats. The aim of present study was to describe the morphological aspects of male genital organs and accessory glands using macroscopic evaluation, ultrasonography, and radiography, as well as describing semen characteristics post-electroejaculation. The results indicated anatomical characteristics of meerkats are very similar to those of cats, having a prostate, accessory bulbourethral glands, and an elongated and radiopaque structure in the penis, which is indicative of there being a baculum. The testicular volume was 0.81 cm³ (± 0.10) and the relative testis weight was 1.37 cm³/kg (± 0.15). Both testicles are present in the scrotum, which has an ellipsoidal shape, homogeneous texture, hypoechoic parenchyma and are encased in a hyperechoic tunica albuginea. Electroejaculation was effectively induced in all animals for semen collection with utilization of medetomidine and ketamine. The values semen samples variables were as follows for volume - 0.125 ± 0.193 mL, motility - 19.8 ± 18.6 %, vigor - 1.9 ± 1.0, concentration - 40.5 ± 25.2 × 10⁶ sperm/mL and morphologically normal sperm - 10.8 ± 6.6 %. This is the first study in which there is a description of morphological and imaging aspects of the male reproductive tracts of meerkats, as well as the seminal characteristics after using electroejaculation for semen collection. Knowledge of anatomical and seminal characteristics is essential for implementation of assisted reproduction programs, as well as reproductive management in the species.

Suppression of ovarian activity in a captive African Lion Panthera leo after deslorelin treatment

Abstract: With the intent to evaluate the efficiency of a contraceptive treatment for cyclic ovarian suppression in African Lionesses Panthera leo using a Gonadotrophin-Releasing Hormone (GnRH) agonist bioimplant, noninvasive fecal steroid assay associated with the observation of the behavioral estrus were employed for a period of 36 months.  Five captive adult females, maintained with a vasectomized male, subcutaneously received a 9.4mg deslorelin acetate implant.  The treatment initially stimulated behavioral estrus along with ovarian activity, demonstrated by an estrogen increase in two lionesses.  A rise in progesterone concentration in two other animals suggested possible treatment-induced ovulation.  After the initial period, deslorelin prevented ovarian activity for at least 22 months.  Two females exhibited signs of behavioral estrus after 22 and 31 months.  A third lioness with an increased estrogen concentration did not exhibit behavioral estrus signs or a consequent progesterone surge until 33 months after implantation, suggesting a possible resumption of ovarian activity.  One female did not exhibit any behavioral estrus signs nor a rise in steroid levels after the “treatment-induced” estrus throughout the entire experiment (36 months).  One lioness died after 15 months without exhibiting signs of estrus or an increased progesterone level, however, the estrogen concentration increased 12 months post-implantation, suggesting resumed ovarian activity.  The study showed that long-term treatment with a GnRH agonist can be extremely effective as a contraceptive treatment in African lionesses, however, the duration of contraception may vary among individuals and may bear the risk of permanent loss of normal ovarian activity.  

Field friendly method for wild feline semen cryopreservation

The aim of this study was to develop a field-friendly method for free-living jaguar and cougar semen cryopreservation.  Six captive Jaguars Panthera onca and three captive Cougars Puma concolor were chemically restrained with a combination of medetomidine (0.08–0.1 mg/kg) and ketamine (5 mg/kg).  Semen was collected through a tomcat urinary catheter with an open end, diluted for a final concentration of 50 x 106 sperm/mL in a TRIS-egg yolk extender and packaged into 0.25 mL straws.  We compared two cooling methods: CoolA - in which straws were placed in a glass tube that was placed in a glass bottle containing water (600mL at 38°C) and transferred to a polystyrene container (12L) containing an 11cm column of ice and water at room temperature; CoolB – where the glass bottle – straws kit was transferred to a 4.26L cooler containing nine blocks (81cm3) of Ice Foam recyclable ice, previously frozen in liquid nitrogen.  The sperm volume varied from 2 to 720 µl for the jaguars and from 80 to 140 µl for the cougars.  Sperm concentration varied from 224 to 5,115 x106 sperm/mL for the jaguars and from 485.7 to 562.5 x 106 sperm/mL for the cougars.  Concerning the cooling treatments, there was no difference in frozen-thawed sperm quality between the methods, in both species.  Thereby, the cooling method using recyclable ice frozen in liquid nitrogen can be used for semen cryopreservation in wild felines, eliminating the need for electric energy.

Can jaguar (Panthera onca) ovulate without copulation?

Threatened of extinction in Brazil, the jaguar is the largest predator in Latin America, playing an important role in the ecosystem where it is inserted. Despite of some important studies in this species, its reproductive physiology needs to be better understood for the development of more effective reproductive biotechnologies. One well studied biological aspect is the occurrence of ovulation following stimulation of the vaginal floor during copulation. This mechanical stimulation is responsible for the induction of ovulation in domestic and wild cats. Thus, the objective of the present study was to evaluate whether ovulation in captive jaguars can be induced by the above-mentioned mechanical stimulation but also by other forms of sensory stimulation. Nine jaguar (Panthera onca) females and six males were divided into three groups: Group 1 (four females), in which the females were close to the males, but with no possibility of copulation; Group 2 (three females), in which the females were in the same enclosure as the males, thereby being able to copulate; and Group 3 (two females), in which the females were completely isolated from any male of the species. Follicular growth was stimulated by administration of 800 IU of eCG, conducted three or five days before LOPU. In order to have certainty about the occurrence of ovulation, the ovaries were assessed by laparoscopy allowing the visualization of ovarian structures including follicles, recent ovulations, corpora hemorrhagica (CH) and corpora lutea (CL). Multiple CH were observed in the 2 females housed with males, as well as the two females kept in proximity of males, i.e. only visual contact (Group 1). None of the females in complete isolation from males showed CH or ovulation spots (Group 3). In summary, the seven females in contact or near proximity with males had multiple ovulations, regardless of copulation or not. Based on this evidence, we have established that jaguars are capable of two forms of induced ovulation: 1) the "mechanical" coitus-induced form that is traditional and thoroughly described for felines; 2) a "sensorial" form in which the nearby presence of a male can induce ovulation through the visual, olfactory and/or auditive senses. Further research is required for establishing the mechanisms and chemical mediators of sensorial stimulation. In addition, and consistent with expected results, we confirmed that females that received the same stimulation are incapable of ovulating when not exposed to any form of stimulation by males.

Copulatory behavior of the Jaguar Panthera onca (Mammalia: Carnivora: Felidae)

The relevance of the Jaguar in  Brazilian fauna is incompatible with the lack of literature regarding its reproductive behavior, showing that research in this area should be intensified.  The knowledge of its basic reproductive behavior is extremely important for understanding the fertility factors of the species and the role it plays in its ecosystem.  In this study, we analyzed 210 sequences of sexual behaviors of Jaguars Panthera onca starting from proceptivity of the female and ending with copulation; this sequence is called the copulatory behavior.  Behavioral sequences were filmed, and the observed behaviors were analyzed and recorded including occurrence frequency.  Different behaviors were observed in association with two types of copulation, it was understood that copulation occurs with and without penile penetration.  The information found in the present study is valuable for the reproductive management of Jaguars.