Testicular volume and semen characteristics in the endangered southern muriqui (Brachyteles arachnoides)

Abstract

Background The southern muriqui (Brachyteles arachnoides) is an endangered Neotropical primate. Semen collection and description of its traits, as well as testicular morphometry, have never been reported for this species. Methods Testicles from five healthy adult captive southern muriqui were measured, and semen was collected by rectal probe electrostimulation (RPE). Results and Conclusions A solid coagulum was identified in all ejaculates, and none of them liquefied, spontaneously or non‐spontaneously. It was possible to collect semen using RPE, and although solids coagula did not liquefy, we managed to describe ejaculates characteristics and also confirmed that southern muriqui have relatively large testes size. Further investigations are needed to improve coagulum handling, to achieve a better spermatozoa recovery aiming its application in assisted reproductive technologies.

Changes in Sperm Morphology, Morphometry, and Motility from the Epididymis to the Vas Deferens in Rheas (Rhea americana, Linnaeus, 1758)

“…We emphasize, however, that the data from the evaluation of the five animals are still highly relevant, given the scarcity of information in this species. Indeed, it is worth noting that similar sample sizes were used in previous studies to describe sperm parameters of other wild species, from critically endangered Southern muriqui (Brachyteles arachnoides) [45] and Bornean orangutans (Pongo pygmaeus) [46] to species of least concern, such as six-banded armadillos (Euphractus sexcinctus) [47] and crab-eating foxes (Cerdocyon thous) [48]. Therefore, numerous directions for future studies will come from these initial results as the description of functional aspects of the rhea sperm, such as the kinetic parameters determined by computer analysis, mitochondrial activity, and chromatin status.…”

Semen cryopreservation in golden‐headed lion tamarin,Leontopithecus chrysomelas

“…Immediately after ejaculation, samples were diluted into 200 μl of Biggers‐Whitten‐Whittingham medium (BWW – 94.59 mM NaCl, 4.78 mM KCl, 1.71 mM CaCl 2 ·2H 2 O, 1.19 mM KH 2 PO 4 , 1.19 mM MgSO 4 , 5.07 mM NaHCO 3 , 20 mM HEPES, 0.25 mM sodium pyruvate, 21.58 mM sodium lactate, 5.56 mM glucose, 0.3% v/w bovine serum albumin, 50 mg/L streptomycin; 100,000 IU/L G‐penicillin, 1 ml/L 0.5% phenol red) at 37°C (Rui et al, ; Arakaki et al, ). Semen volume was measured by weighing the tube containing the diluted semen using a precision scale (AUX220; Shimadzu®, Tokyo, Japan), and then the tube's weight and the amount of extender used were subtracted, assuming that sperm density in golden‐headed lion tamarin is supposed to be equal to that of humans, 1 g/ml, according to WHO (WHO, ).…”

Reproductive one health in primates

“…The coagulum forms soon after ejaculation and is meant to enhance the probability that the mating male will outcompete other males by holding the sperm and gradually releasing it and/or by creating a physical plug which hampers the sperm from the next male from reaching the ovum. The plug, however, also greatly hampers assisted reproductive techniques such as semen evaluation, quantification, and cryopreservation, as additional handling is necessary to cryopreserve such samples (Arakaki et al, 2019).…”

“…The coagulum forms soon after ejaculation and is meant to enhance the probability that the mating male will outcompete other males by holding the sperm and gradually releasing it and/or by creating a physical plug which hampers the sperm from the next male from reaching the ovum. The plug, however, also greatly hampers assisted reproductive techniques such as semen evaluation, quantification, and cryopreservation, as additional handling is necessary to cryopreserve such samples (Arakaki et al, 2019). The presence of seminal plugs also makes it necessary to confirm patency of the urethra after semen collection via electroejaculation, as life‐threatening obstruction has been documented in lemurs (Chatfield & Penfold, 2007) and macaques (Agnew unpub.…”