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At least 19 recordsLinked to original sources
PubMed1976

Reproductive biology of the male leaf-nosed bat, Macrotus waterhousii in Southwestern United States.

The reproductive biology of the bat Macrotus waterhousii was investigated anatomically and physiologically several times monthly throughout the year. The male spermatogenic cycle is initiated in June; sperm are available in August. Testicular hypertrophy is accompanied by increased levels of testicular ascorbic acid and circulating plasma testosterone. Sperm are present in the seminiferous tubules and later the epididymides from August to early December. Regression in testicular size begins in late September and testes are involuted by early December. Levels of testicular ascorbic acid and plasma testosterone decline at this time, although detectable amounts of both are present year-round. Mature sperm are absent from the male tract after late November or early December. The accessory sex gland complex and Cowper's glands undergo an annual cycle in synchrony with the testicular cycle. The accessory complex contains fructose, the concentration of which varies seasonally in direct proportion to glandular hypertrophy. Only trace levels of fructose are elaborated by Cowper's glands undergo an annual cycle in synchrony with the testicular cycle. The accessory complex contains fructose, the concentration of which varies seasonally in direct proportion to glandular hypertrophy. Only trace levels of fructose are elaborated by Cowper's glands. In contrast to vespertilionid bats, where the accessory glands remain enlarged and active when testes involute, those in Macrotus regress. The penis differs structurally from that of other temperate North American bats, primarily by lacking a bony baculum and specialized erectile accessory corpus cavernosus bodies. Males are not reproductively active in their first autumn.

Animals↗
PubMed1976

Effects of Sevin on the reproductive biology of the Coturnix.

Adult Coturnix quail (Coturnix coturnix japonica) were subjected to three levels of carbaryl pesticide treatment (Sevin-20 p.p.m., 40 p.p.m., and 400 p.p.m) and monitored to observe any modifications in either their reproductive biology or behavior. There was an increase in the amount of pesticide excreted with increasing treatment levels during the first 48 hours following intubation, after which pesticide levels in the fecal material for all groups approached zero. Addditionally, significant amounts of the pesticide were detected in the egg yolks after pesticide ingestion (treatment levels, 20, 40, and 400 p.p.m. resulted in pesticide residues of 1.58, 2.03, and 3.15 p.p.m., respectively). Egg production was significantly reduced (p less than or equal to 0.05), although egg viability was not affected by the pesticide stress. Agonistic behavior decreased in males while it increased in the females following pesticide ingestion.

Aggression↗
PubMed2026

A high-quality draft genome assembly of Johnsongrass illuminates relationships between polyploidization, crop-wild hybridization, and reproductive biology.

Johnsongrass [Sorghum halepense (L.) Pers.] is an allopolyploid, rhizomatous, perennial grass species and one of the most troublesome weeds in global agriculture. We assembled the first Johnsongrass genome to clarify poorly understood genetic factors influencing variable rates of crop-wild hybridization with cultivated sorghum [S. bicolor (L.) Moench]. The draft genome assembly has a total size of 3.26 Gb and BUSCO completeness of 95.3%. We also report the first evolutionary analysis of INHIBITION OF ALIEN POLLEN (IAP), the only known cross-(in)compatibility locus in the genus. Our results reveal an evolutionary history of genome instability, including the loss of distinct parental subgenomes, and suggest that Nebraska accession 'J-37,' the genome donor, is a segmental allotetraploid that may function as a diploid or aneuploid during meiosis. Genome instability could explain observations of variable ploidies in Johnsongrass and facilitate ongoing hybridization with sorghum where gamete ploidies and IAP alleles match. Given this information, we provide a suggested research framework for studying evolution and gene expression in the Sorghum genus where crop-wild hybridization occurs and for predicting the potential for hybridization between specific crossing partners. Collectively, this work will bolster efforts to study and manage reproductive biology in other crop-wild polyploid complexes.

Sorghum↗
PubMed2026

The Polish Konik Horse: A Multidisciplinary Review of Its Origin, Genetics, Ecology, Health, Behaviour and Reproductive Biology.

The Polish Konik horse (PKH) is one of Europe's best-known native conservation breeds. Traditionally associated with the extinct Eurasian tarpan and conservation grazing, the breed has recently become the subject of multidisciplinary research encompassing genetics, ecology, health, behaviour and reproduction. This narrative review summarises current knowledge on the biological characteristics and contemporary scientific significance of the PKH. Literature published between 2005 and 2026 was identified through searches of PubMed, Scopus, Web of Science and Google Scholar and narratively synthesised. Available evidence suggests that, despite severe historical bottlenecks, the PKH has retained considerable genetic diversity and its characteristic maternal and paternal founder-line structure. Recent molecular studies have revised traditional concepts of the breed's origin, while ecological research supports its important role in conservation grazing and wetland restoration. Behavioural and reproductive studies indicate stable temperament, high reproductive efficiency and adaptation to extensive management systems. However, current knowledge is derived predominantly from observational studies, with relatively few comparative investigations and limited genomic and longitudinal data. The PKH represents a valuable model for research on conservation genetics, environmental adaptation, animal welfare, reproductive biology and ecosystem management. Further interdisciplinary studies are needed to strengthen the evidence base for conservation and breeding strategies.

Polish Konik horse↗
PubMed1977

The role of the psychiatrist in a reproductive biology clinic.

The psychiatrist consulting to an infertility clinic is confronted with a variety of clinical issues and problems. The couple arrives with anxiety, for a work-up that in itself will be traumatic. The psychiatrist's role is to weed out distortions and issues that are unreal. Psychosexual and marital conflicts may also masquerade as an infertility problem. The simplest manner in which psychologic factors can be thought of as causing infertility is through their effect on sexual performance. Brief therapeutic techniques include education, encouragement, and behavioral techniques to improve performance. Psychoanalytically oriented techniques include relating the symptom to unconscious conflicts stemming from the past and understanding the secondary gain of the symptom. The psychiatrist's role may also involve helping the couple to deal with the outcome of the infertility work-up, including helping the couple to mourn the fact that they cannot have children, assisting in decisions involving artificial insemination and adoption, and helping the couple to deal with uncertainty when no definite cause for the infertility has been discerned. The multiplicity of possible psychologic interventions requires the psychiatrist to be ubiquitous. In the light of this, a number of suggestions are listed as to how a psychiatrist might best be utilized.

Adaptation, Psychological↗
PubMed1979

The reproductive ecology of the house mouse.

This paper attempts to integrate the physiological and ecological perspectives of the reproductive biology of the house mouse (Mus musculus). The endeavor is made within a larger context to provide a prototype for mammalian reproductive ecology in general. Specifically, the environmental regulation of the reproduction of Mus musculus is examined in relation to its ecological opportunism and, in particular, in relation to its history of global colonization. House mice can live as commensals of man or under totally feral conditions. Stable, high density, commensal populations are characterized by an insular division of the living space into demeterritories, each dominated by a single male. Feral populations typically are characterized by temporal, spatial, and social instability. Territoriality is improbable under such conditions, particularly given the necessity for large home ranges in most feral habitats. In both feral and commensal populations, however, male aggressiveness promotes the large-scale dispersal of young, all of which are potential colonizers. Of the ten or so environmental factors known to influence reproduction in house mice, seven probably are of routine importance in natural populations: diurnal modulation by daily light:dark cycles; caloric intake; nutrition; extreme temperature; agaonistic stimuli; socio-tactile cues; and priming pheronomes. The last two factors named operate directly on the secretion of luteinizing hormone or prolactin; the others act at many points in the reproductive system. Reproduction in the house mouse seems divorced from photoperiodically induced seasonality; indeed, this species breeds well even in constant darkness. Seasonal breeding may or may not then occur, depending upon dietary considerations, with or without a secondary interaction with variation in ambient temperature. There is no evidence for a dependence upon secondary plant compounds. Some of the effects of priming pheromones that have been observed previously in laboratory mice probably play no meaningful role in wild populations. The remaining pheromonal phenomena can be conceptualized as a single cueing system that has three components: (a) urinary cues of socially dominant males can accelerate ovulation in females, adult or prepubertal; (b) female urinary cues may elevate pheromonal potency in adult males, thereby forming a feedback loop by which the females elicit their own ovulation; and (c) the male's action on prepubertal females can be blocked by urinary cues emanating from other females. When all of the above is viewed in toto, the reproductive biology of the house mouse seems uniquely suited to support ecological opportunism. The relatively few environmental inhibitors of reproduction in this species should enhance the ability of dispersing young to colonize an exceptionally wide variety of habitats and climates...

Animals↗
PubMed2026

Reproduction on the Rocks: Life History of a Freshwater Macrobioeroding Bivalve.

Macrobioerosion, the excavation and removal of consolidated mineral substrates by macrofauna, is well established in marine systems, where macrobioeroders drive carbonate cycling, sediment production and habitat formation. In freshwater ecosystems, however, it has been documented in only a small number of invertebrate taxa and remains a poorly resolved ecological process. Among these, the teredinid shipworm Lithoredo abatanica represents a remarkable departure from the wood-boring ecology of its family, having evolved to excavate and ingest limestone in fresh water. Despite this remarkable ecological transition, its reproductive biology and life history remain unknown. Here, we investigate the reproductive mode and life history strategy of this species using population size structure, in&#xa0;situ observations of siphonal morphology, and sperm morphometrics. We show that L.&#x2009;abatanica reaches exceptional dimensions, with measured body lengths exceeding 100&#x2009;mm, one intact empty burrow exceeding 200&#x2009;mm and in-water observations indicating burrows possibly exceeding 500&#x2009;mm, establishing it as the largest known freshwater macrobioeroder. Its large size and dense aggregations indicate considerable capacity for local rock breakdown and habitat modification within the Abatan River system (Bohol, Philippines). Recently settled juveniles (<&#x2009;10&#x2009;mm) alongside reproductively mature individuals indicate ongoing recruitment. The morphology of the siphons and calcareous tube appears to preclude direct sperm transfer via pseudocopulation, while sperm morphometrics are consistent with external fertilisation. Together, these findings indicate that L.&#x2009;abatanica reproduces via broadcast spawning with external fertilisation and likely possesses a planktotrophic larval phase. This raises a fundamental question: how does a broadcast-spawning species with planktotrophic larvae maintain populations up to 15&#x2009;km upstream in a flowing freshwater river subject to persistent downstream advection? By resolving the life history of the largest known freshwater macrobioeroder, this study provides critical insight into the persistence, dispersal and ecological role of a globally unique riverine ecosystem engineer.

broadcast spawning↗
PubMed1975

Structure and function of immunoglobulins.

There are five major classes of immunoglobulins - IgG, M, A, D and E. Each is made of two heavy and two light chains or polymers of this basic subunit. The structure of each heavy and light chain consists of a variable region involved in antigen specificity and binding and a constant region which is involved in the class specific properties. The different classes of immunoglobulins differ in the biological properties. Of particular interest is the IgA fraction which provides antibodies in all the external secretions - including the reproductive organs. A few speculations are offered as to the possible role of IgA in reproductive biology.

Amino Acid Sequence↗
PubMed2025

Comparative genomics and transcriptomics of the Spiroplasma glossinidia strain sGff reveal insights into host interaction and trypanosome resistance in Glossina fuscipes fuscipes.

Tsetse (Glossina spp.) are vectors of African trypanosomes, the causative agents of Human and African Animal trypanosomiases, diseases that remain significant medical and socioeconomic challenges in sub-Saharan Africa. In addition to trypanosomes, tsetse harbor both obligate and facultative symbiotic bacteria that can influence vector competence and reproductive biology. One such facultative symbiont, Spiroplasma glossinidia, infects several tsetse species within the Palpalis subgroup. In Glossina fuscipes fuscipes (Gff), the Spiroplasma glossinidia strain sGff induces a trypanosome-refractory phenotype and negatively impacts reproductive fitness by reducing female fecundity. However, the mechanisms behind these Spiroplasma-derived phenotypes remain poorly understood. Here, we report successful in vitro cultivation of sGff and present complete genomes from three sources: in vitro cultured sGff and sGff isolated from both laboratory-maintained and wild-caught (Uganda) Gff flies. Comparative genomic analyses revealed a high degree of similarity in gene content and synteny among these sGff samples, confirming that they represent isolates of the same strain. Phylogenomic analyses placed sGff within the Spiroplasma poulsonii clade. The sGff genome is highly dynamic, containing numerous mobile genetic elements. Additionally, in silico annotations indicate that sGff relies on its host for both lipids and carbohydrates and produces several toxins, all of which could be implicated in the observed trypanosome refractory phenotype. Finally, comparative transcriptomic analysis of sGff from host hemolymph versus in vitro culture provided insights into potential factors relevant to host-symbiont interactions. Our findings provide a foundation for understanding the nutritional dialogue between sGff and its host and identify symbiotic products that may contribute to trypanosome resistance. Furthermore, the establishment of an in vitro culture system for sGff represents a significant resource for future functional studies with potential implications for vector control.

Glossina fuscipes fuscipes↗
PubMed1978

Use of the common marmoset, Callithrix jacchus, in reproductive research.

A self-sustaining colony of common marmosets, Callithrix jacchus, was established for reproductive research. Methods of management were developed to ensure optimal breeding conditions for marmosets in captivity. Studies of the reproductive biology and endocrinology of this species suggest that the common marmoset may be a suitable model for the human in certain aspects of the ovarian cycle, pregnancy, puberty and the hypothalamic and pituitary control of luteinizing hormone secretion. The rapid rate of reproduction of C. jacchus in captivity allows a relatively large colony to be maintained at moderate cost and also makes this species a most suitable laboratory primate for longer term studies of the safety and efficacy of new contraceptive methods.

Aging↗