Pituitary content of luteinizing hormone reveals species differences in the reproductive synchrony between males and females in Australian flying-foxes (genus Pteropus)

2003 ◽  
Vol 15 (4) ◽  
pp. 255 ◽  
Author(s):  
G. M. O'Brien ◽  
J. R. McFarlane ◽  
P. J. Kearney
Keyword(s):  
Luteinizing Hormone ◽  
Time Frame ◽  
Early Summer ◽  
Environmental Cues ◽  
Mating Season ◽  
Reproductive Seasonality ◽  
Flying Foxes ◽  
Pregnancy And Lactation ◽  
Males And Females ◽  
Flying Fox

Flying-foxes (genus Pteropus, suborder Megachiroptera) are long-lived tropical mammals. Their seasonal reproduction appears to be regulated by an endogenous, circannual rhythm modified by multiple environmental cues. Luteinizing hormone (LH) content in pituitary extracts was examined to establish the broad time-frame of pituitary stages in the reproductive seasonality of the flying-foxes. A comparison was made between the grey-headed flying-fox P. poliocephalus, which mates and conceives in autumn, and the little red flying-fox P. scapulatus, which mates and conceives in spring. In P. scapulatus, LH was maximum during the spring mating season at 1494 ng mg−1 in males and 896 ng mg−1 in females. In P. poliocephalus males, LH increased to 1082 ng mg−1 in early summer, 4 months before the mating season; LH concentrations in male P. poliocephalus returned to a low of 222 ng mg−1 by the time of the autumn mating, by which time the female P. poliocephalus expressed elevated LH concentrations (624 ng mg−1). Apparently in P. poliocephalus, the peak LH concentrations in females are delayed by 4 months relative to LH concentrations in males. This is associated with 4 months of energetic courtship on the part of male P. poliocephalus, which is not observed in P. scapulatus, the fertility of which is synchronized between the sexes. The heterologous radioimmunoassay developed using monoclonal antibody 518B7 confirmed classic suppression of LH during pregnancy and lactation in flying-foxes and LH elevation in response to gonadectomy. Juveniles generally had pituitary levels similar to non-breeding levels in adults.

Sexual differences in the annual lipid cycle of the big brown bat Eptesicus fuscus

1989 ◽  
Vol 67 (8) ◽  
pp. 1891-1894 ◽  
Author(s):  
David H. Pistole
Keyword(s):  
Eptesicus Fuscus ◽  
Fat Deposition ◽  
Caloric Content ◽  
Basic Pattern ◽  
Mating Season ◽  
Male And Female ◽  
Big Brown Bats ◽  
Big Brown Bat ◽  
Pregnancy And Lactation ◽  
Males And Females

The annual lipid cycle in male and female big brown bats, Eptesicus fuscus, was studied in relation to the reproductive patterns for each sex. The basic pattern of lipid deposition and use was similar in males and females; however, there were differences between the sexes in the timing of these activities. Females began rapid fat deposition 1 month earlier than males. The beginning of rapid fat deposition in females is associated with the end of lactation and in males with the end of spermatogenesis and the peak mating season. Rates of fat use were similar between the sexes for the entire hibernation period, but the rate in females was more consistent than the rate in males. The caloric content of male bats did not differ throughout the year, but females had higher values during pregnancy and lactation than at other times of the year. Differences between the sexes in the timing of specific events within the annual lipid cycle appear to be adaptations for optimizing reproductive success.

Selenium Role in Reproduction, Pregnant/Postpartum Women and Neonates: A Current Study

2020 ◽  
Vol 17 (1) ◽  
pp. 28-37
Author(s):  
Tabinda Sattar
Keyword(s):  
Infant Development ◽  
Selenium Deficiency ◽  
Human Reproduction ◽  
Postpartum Women ◽  
Female Reproduction ◽  
Pregnancy And Lactation ◽  
Males And Females ◽  
One Year ◽  
Selenium Supplements

Background: Selenium is a micronutrient, although required in low amounts, its importance in male and female reproduction is well known. Objectives: The core purpose of this study is to evaluate the role of selenium in human reproduction, during pregnancy/ lactation in women and newborns. The review explains side by side the sources of selenium, required amounts of selenium in humans and during pregnancy or lactation. Methods: Selenium deficiency is a major cause of male infertility. Similarly, selenium deficiency, both in pregnant and postpartum women, would greatly affect the health of the newborn baby in all respects. The effect of maternal selenium upon the fetus and the neonates even one year after birth has been explained with some recent examples. Results: The study elaborates the fact that the selenium deficiency in pregnancy and lactation is common due to fetal/infant development, so selenium supplements must be provided in order to overcome these deficiency symptoms. Conclusions: The better reproductive health in humans is possible due to the sufficient amounts of selenium present both in males and females as well.

Reproductive seasonality and the effect of the GnRH agonist deslorelin as a contraceptive in captive male Black Flying-foxes (Pteropus alecto)

2012 ◽  
Vol 77 (3) ◽  
pp. 652-661 ◽  
Author(s):  
D.F. Melville ◽  
G.M. O'Brien ◽  
E.G. Crichton ◽  
P. Theilemann ◽  
A. McKinnon ◽  
...  
Keyword(s):  
Gnrh Agonist ◽  
Reproductive Seasonality ◽  
Flying Foxes

Plasma testosterone surge and luteinizing hormone beta (LH-β) following parturition: lack of association in the male rat

1995 ◽  
Vol 133 (3) ◽  
pp. 366-374 ◽  
Author(s):  
Robert F McGivern ◽  
Ralph HM Hermans ◽  
Robert J Handa ◽  
Lawrence D Longo
Keyword(s):  
Luteinizing Hormone ◽  
Cesarean Section ◽  
Gnrh Antagonist ◽  
Male Rat ◽  
Plasma Testosterone ◽  
Treatment Groups ◽  
Natural Birth ◽  
Males And Females ◽  
Lh Secretion

McGivern RF, Hermans RHM, Handa RJ, Longo LD. Plasma testosterone surge and luteinizing hormone beta (LH-β) following parturition: lack of association in the male rat. Eur J Endocrinol 1995; 133:366–74. ISSN 0804–4643 Studies examining the role of luteinizing hormone (LH) in the initiation of the postnatal surge of testosterone in the male rat have produced ambiguous results. We examined the pattern of postnatal LH secretion in the newborn male rat, coincident with plasma testosterone levels, using a specific monoclonal antibody for LH-β. In some males, we attempted to block LH secretion and the postnatal testosterone surge by injecting males with a gonadotropin-releasing hormone (GnRH) antagonist, an LH antibody or progesterone immediately after delivery by cesarean section on day 22. Following injection, animals were immediately sacrificed (time 0) or housed in a humidified incubator maintained at 30°C until sacrifice at 60, 120, 240, 360 or 480 min after delivery. Plasma from individual animals was measured subsequently for LH-β and testosterone by radioimmunoassay. Results revealed a postnatal surge of testosterone which peaked at 2 h after delivery in males from all treatment groups. This testosterone surge was not accompanied by a postnatal rise in plasma LH-β in any group. Administration of the GnRH antagonist or the ethanol vehicle produced a transient drop of approximately 25% in LH-β levels at 60 min but did not decrease the postnatal testosterone surge in the same animals. Additional studies in untreated males and females born by cesarean section or natural birth also failed to reveal a postnatal rise in plasma LH-β during the first 3 h after birth. Plasma levels in both sexes were significantly lower in animals delivered by cesarean section compared to natural birth. Overall, these results indicate that the postnatal surge of testosterone occurs without a corresponding surge of detectable LH-β in the male rat. Robert F McGivern, 6363 Alvarado Ct, Suite 200H. San Diego, CA 92120, USA

scholarly journals A comparison of nutritional value of native and alien food plants for a critically endangered island flying-fox

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0250857
Author(s):  
Laura A. Pulscher ◽  
Ellen S. Dierenfeld ◽  
Justin A. Welbergen ◽  
Karrie A. Rose ◽  
David N. Phalen
Keyword(s):  
Plant Species ◽  
Soluble Sugars ◽  
Critically Endangered ◽  
Food Plants ◽  
Nutritional Requirements ◽  
Nutritional Content ◽  
Alien Plant ◽  
Flying Foxes ◽  
Christmas Island ◽  
Flying Fox

Habitat loss and alteration are two of the biggest threats facing insular flying-foxes. Altered habitats are often re-vegetated with introduced or domestic plant species on which flying-foxes may forage. However, these alien food plants may not meet the nutritional requirements of flying-foxes. The critically endangered Christmas Island flying-fox (CIFF; Pteropus natalis) is subject to habitat alteration and the introduction of alien food plants, and therefore is a good model species to evaluate the potential impact of alien plant species on insular flying-foxes. In this study, we evaluated nutritional content of native food plants to determine how flying-foxes historically met their nutritional requirements. Furthermore, we compared the nutritional content of native and alien fruits to predict possible impacts of alien plants on insular flying-foxes. Native and alien fruits and flowers, and native foliage (leaves, petals, and petioles) commonly consumed by the CIFF were collected and evaluated for soluble sugars, crude protein, non-fiber carbohydrates, and nine minerals. Evaluation of native food plants suggests that flying-foxes meet energy requirements by consuming fruit and nectar. However, fruit and nectar are low in protein and essential minerals required for demanding life periods; therefore, flying-foxes likely supplement their diets with pollen and foliage. Thus, flying-foxes require a diverse array of plants to meet their nutritional requirements. Compared to native fruits, alien fruits contained significantly higher non-fiber carbohydrates, and this may provide an important energy source, particularly from species that bear fruit year-round. Median mineral concentrations in alien fruit species, however, were deficient compared to native fruits, suggesting major (or even seasonal) shifts in the proportion of alien species in the CIFF diet could lead to nutritional imbalances. This study confirms the need to quantify nutritional parameters in addition to feeding ecology when evaluating habitat quality to inform conservation actions that can be applied both locally and globally.

scholarly journals A New Hendra Virus Genotype Found in Australian Flying Foxes

2021 ◽  
Author(s):  
Jianning Wang ◽  
Danielle E Anderson ◽  
Kim Halpin ◽  
Xiao Hong ◽  
Honglei Chen ◽  
...  
Keyword(s):  
Genetic Relatedness ◽  
Phylogenetic Analyses ◽  
Inflammatory Lesion ◽  
Hendra Virus ◽  
Virus Genotype ◽  
Flying Foxes ◽  
Qrt Pcr ◽  
Genotype 2 ◽  
Pcr Assays ◽  
Flying Fox

Abstract Background Hendra virus (HeV) has caused lethal disease outbreaks in humans and horses in Australia. Pteropid bats (flying foxes) are the wildlife reservoir from which the virus was first isolated in 1996. Following a heat stress mortality event in Australian flying foxes in 2013, a novel HeV variant was discovered. This study describes the subsequent surveillance of Australian flying foxes for this novel virus over a nine year period using qRT-PCR testing of bat tissues submitted primarily for Australian bat lyssavirus (ABLV) diagnosis. Genome sequencing and characterisation of the novel HeV variant was also undertaken. Methods Spleen and kidney samples harvested from flying fox carcasses were initially screened with two real-time qRT-PCR assays specific for the prototype HeV. Two additional qRT-PCR assays were developed specific for the HeV variant first detected in samples from a flying fox in 2013. Next-generation sequencing and virus isolation was attempted from selected samples to further characterise the new virus. Results Since 2013, 98 flying foxes were tested and 11 were positive for the new HeV variant. No samples were positive for the original HeV. Ten of the positive samples were from grey-headed flying foxes (GHFF, Pteropus poliocephalus), however this species was over-represented in the opportunistic sampling (83% of bats tested were GHFF). The positive GHFF samples were collected from Victoria and South Australia and one positive Little red flying fox (LRFF, Pteropus scapulatus) was collected from Western Australia. Immunohistochemistry (IHC) confirmed the presence of henipavirus antigen, associated with an inflammatory lesion in cardiac blood vessels of one GHFF. Positive samples were sequenced and the complete genome was obtained from three samples. When compared to published HeV genomes, there was 84% sequence identity at the nucleotide level. Based on phylogenetic analyses, the newly detected HeV belongs to the HeV species but occupies a distinct lineage. We have therefore designated this virus HeV genotype 2 (HeV-G2). Attempts to isolate virus from PCR positive samples have not been successful. Conclusions A novel HeV genotype (HeV-G2) has been identified in two flying fox species submitted from three states in Australia, indicating that the level of genetic diversity for HeV is broader than first recognised. Given its high genetic relatedness to HeV, HeV-G2 should be considered a zoonotic pathogen.

scholarly journals Macroevolutionary consequences of sexual conflict

2018 ◽  
Vol 14 (6) ◽  
pp. 20180186
Author(s):  
Jo S. Hermansen ◽  
Jostein Starrfelt ◽  
Kjetil L. Voje ◽  
Nils C. Stenseth
Keyword(s):  
Sexual Selection ◽  
Genetic Architecture ◽  
Time Frame ◽  
Sexual Conflicts ◽  
Males And Females ◽  
Selection For ◽  
Evolutionary Consequences ◽  
Future Work ◽  
Shared Genetic

Intralocus sexual conflicts arise whenever the fitness optima for a trait expressed in both males and females differ between the sexes and shared genetic architecture constrains the sexes from evolving independently towards their respective optima. Such sexual conflicts are commonplace in nature, yet their long-term evolutionary consequences remain unexplored. Using a Bayesian phylogenetic comparative framework, we studied the macroevolutionary dynamics of intersexual trait integration in stalk-eyed flies (Diopsidae) spanning a time frame of more than 25 Myr. We report that increased intensity of sexual selection on male eyestalks is associated with reduced intersexual eyestalk integration, as well as sex-specific rates of eyestalk evolution. Despite this, lineages where males have been under strong sexual selection for millions of years still exhibit high levels of intersexual trait integration. This low level of decoupling between the sexes may indicate that exaggerated female eyestalks are in fact adaptive—or alternatively, that there are strong constraints on reducing trait integration between the sexes. Future work should seek to clarify the relative roles of constraints and selection in contributing to the varying levels of intersexual trait integration in stalk-eyed flies, and in this way clarify whether sexual conflicts can act as constraints on adaptive evolution even on macroevolutionary time scales.

scholarly journals Roost of Gray Flying Foxes (Pteropus griseus) in Indonesia and Records of a New Hunting Threat

Diversity ◽  
2018 ◽  
Vol 10 (3) ◽  
pp. 102 ◽  
Author(s):  
Sheherazade ◽  
Susan Tsang
Keyword(s):  
Small Islands ◽  
Anecdotal Evidence ◽  
Conservation Action ◽  
International Union ◽  
Flying Foxes ◽  
North Sulawesi ◽  
Fruit Bat ◽  
Data Deficient ◽  
Conservation Threats ◽  
Flying Fox

Pteropus griseus (gray flying fox) is a species of Old World fruit bat that is listed by the International Union for Conservation of Nature (IUCN) as Data Deficient. The species is found on small islands in the Lesser Sundas and Sulawesi, and is endemic to Indonesia, but no contemporary roosts are known, and the last study of the species was in Timor in the Lesser Sundas. In this study, we describe the first known day roost in Sulawesi for Pteropus griseus and collected anecdotal evidence regarding conservation threats to the colony. We compared data from flying foxes collected from this roost to other P. griseus specimens and those of closely related co-occurring species to confirm its identity. We confirmed that this roost is likely of Pteropus griseus, though the subspecies identity remains to be determined. However, it is newly threatened by middlemen traders of bat meat from North Sulawesi arriving to encourage local villagers near the roost to hunt the bats. Elevated levels of hunting may deplete the entire colony in a single season should no conservation action be taken to safeguard the roost.

scholarly journals Thyroid hormone concentrations associated with age, sex, reproductive status and apparent reproductive failure in the Amazon river dolphin (Inia geoffrensis)

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
T R Robeck ◽  
R S Amaral ◽  
V M F da Silva ◽  
A R Martin ◽  
G A Montano ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Reference Intervals ◽  
Amazon River ◽  
Adult Males ◽  
Serum Samples ◽  
Pregnant Females ◽  
Pregnancy And Lactation ◽  
Inia Geoffrensis ◽  
Males And Females ◽  
Group Sex

AbstractThis study was conducted to characterize immunoreactive thyroid hormone concentrations in wild Amazon river dolphins, also called boto (Inia geoffrensis) by age group, sex, pregnancy and lactation status, and to determine if thyroid hormone concentration differences could be detected between pregnant females with and without successful parturition outcomes. Radioimmunoassays were used to analyse total T3 and total T4 in 182 serum samples collected from 172 botos living in the Mamirauá Sustainable Development Reserve, in the Brazilian Amazon from 2003 through 2015. Age significantly affected tT3 and tT4 concentrations in males, with values in immature males and females being significantly lower than those in adult males, whereas no age effects were noted between immature females and adult non-pregnant, non-lactating females. Significant sex differences were noted in tT3 concentrations between immature males and females and in tT4 concentrations between adult males and females. These resulted in significant differences in the tT3:tT4 ratio between males and females within the immature and adult groups. Lactating and non-pregnant adult females had significantly higher tT3 concentrations than pregnant females, and this difference was primarily driven by a 12% drop in tT3 concentrations during the last two-thirds of pregnancy. No differences in thyroid hormone concentrations were detected between females diagnosed as pregnant and later found to have or not have a live calf. These results are the first to define thyroid hormone reference intervals and normal physiological variations in a wild population of river dolphins.

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