Differentiation between male and female in the reproductive period

2018 ◽  
pp. 29-33
Author(s):  
Helene Deutsch
Keyword(s):  
Reproductive Period ◽  
Male And Female

Seasonal changes of brain GnRH-I, -II, and -III during the final reproductive period in adult male and female sea lamprey

2011 ◽  
Vol 170 (2) ◽  
pp. 276-282 ◽  
Author(s):  
Stacia A. Sower ◽  
Eileen Balz ◽  
Allisan Aquilina-Beck ◽  
Scott I. Kavanaugh
Keyword(s):  
Adult Male ◽  
Seasonal Changes ◽  
Sea Lamprey ◽  
Reproductive Period ◽  
Male And Female

scholarly journals Reproductive Ecology of Male and Female Strobili and Mating System in Two Different Populations ofPinus roxburghii

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Chandra Mohan Sharma ◽  
Vinod Prasad Khanduri ◽  
Sunil Kumar Ghildiyal
Keyword(s):  
Mating System ◽  
Natural Populations ◽  
Production Capacity ◽  
Pollen Grains ◽  
Seed Orchard ◽  
Reproductive Period ◽  
Female Cone ◽  
Lower Altitude ◽  
Female Ratio ◽  
Male And Female

We studied several flowering traits, namely, male-female cone phenology, male-female cone production per tree, mating system, sex ratio, air-borne pollen grains and pollen migration, over four successive years in two different natural populations ofP. roxburghiifrom Garhwal Himalaya, India. Assessment of each trait mentioned except pollen dispersion was done by selecting five representative trees randomly in each population. The pollen migration was studied on naturally isolated source trees. The pollen trapping was done in all directions up to 2.5 km. The average reproductive period inP. roxburghiiwas 36 days with 3–5 days protandry. There were significant year and population effects for male and female cone output and pollen grains production per tree. In mass production year (1999), an average production of pollen cone per tree was estimated as42.44±8.32×103at lower altitude and28.1±0.89×103at higher altitude. The controlled pollination results in high level of outcrossing with 90% seed setting. We conclude that the high male-female ratio and tremendous pollen production capacity inP. roxburghiiindicate high male competition among trees within populations. The isolation strip of 600 m is considered minimal for the management of seed orchard.

Timing and patterns of mating in a free-ranging population of Lycosa tarantula (Araneae, Lycosidae) from central Spain

2003 ◽  
Vol 81 (3) ◽  
pp. 552-555 ◽  
Author(s):  
Carmen Fernández-Montraveta ◽  
Mariano Cuadrado
Keyword(s):  
Multiple Mating ◽  
Wolf Spider ◽  
Female Mate Choice ◽  
Reproductive Period ◽  
Operational Sex Ratio ◽  
Central Spain ◽  
Male And Female ◽  
Early Maturation ◽  
Free Ranging ◽  
Female Maturation

We analysed the timing and patterns of mating in a free-ranging population of the wolf spider Lycosa tarantula (Araneae, Lycosidae) in central Spain monitored during a whole reproductive period. The population showed a polygamous mating system. However, the frequency of multiple mating was relatively low. Reproductive success of males was highly skewed, as a few males monopolized most of the copulations recorded. Males matured slightly before females but male and female maturation largely overlapped. Mortality of subadult spiders was independent of their sex, and the operational sex ratio was 1:1. Early maturation of females resulted in a larger number of visiting males but not higher mating success, indicating the possibility of female mate choice in this species.

scholarly journals Monitoring the feeding and parental care behavior of a pair of free-living owls (Tyto furcata) in the nest during the reproductive period in Rio de Janeiro, Brazil

2024 ◽  
Vol 84 ◽  
Author(s):  
H. V. R. Dias ◽  
A. J. Almeida ◽  
J. A. Maia-Júnior ◽  
R. R. Ribeiro ◽  
K. A. A. Torres-Cordido ◽  
...  
Keyword(s):  
Rio De Janeiro ◽  
Eating Habits ◽  
Video Camera ◽  
Reproductive Period ◽  
Small Rodents ◽  
Free Living ◽  
Male And Female ◽  
Barn Owls ◽  
Care Behavior ◽  
Janeiro State

Abstract The American Barn Owl (Tyto furcata) lives in urban, periurban and wild environments and feeds mainly on small rodents, meaning it has great importance in the biological control of pests. The aim of this work was to describe the reproductive, parental and eating habits of a pair of American barn owls naturally living outside a residence in the urban area of the municipality of Campos dos Goytacazes, Rio de Janeiro state, Brazil. A wood box was installed on an outside wall of the home, monitored by a video camera. A spreadsheet was created to keep track of the observations recorded. The female laid four eggs, and after an incubation period of 30-32 days all the eggs hatched, but only two chicks survived after cannibalism among the chicks. Initially, the male provided the food to the chicks and the female remained in the nest caring for the brood. After approximately a month, the female also began to leave the nest and return with prey, which was offered to the chicks, with the male also continuing this behavior. The chicks left the nest in September, 2017. The data obtained show the existence of cooperation and division of tasks between male and female owls during the reproductive period.

scholarly journals Diet of the oilfish Ruvettus pretiosus (Perciformes: Gempylidae) in the Saint Peter and Saint Paul archipelago, Brazil

2012 ◽  
Vol 60 (2) ◽  
pp. 181-188 ◽  
Author(s):  
Danielle de Lima Viana ◽  
Mariana Travassos Tolotti ◽  
Mariana Porto ◽  
Rodolfo Jorge Vale de Araújo ◽  
Teodoro Vaske Júnior ◽  
...  
Keyword(s):  
Saint Paul ◽  
Reproductive Period ◽  
Shallow Waters ◽  
Mesopelagic Fish ◽  
Male And Female ◽  
Food Items ◽  
Vertical Range ◽  
Flying Fish ◽  
Saint Peter ◽  
Prey Items

Feeding aspects of the oilfish, Ruvettus pretiosus, were studied based on 360 stomachs of both male and female specimens caught off the Saint Peter and Saint Paul Archipelago. The total length of the specimens ranged from 52.4 cm to 189.0 cm. Of the 360 stomachs examined, 135 presented some food and 225 were empty. Thirty-four taxa were identified, represented by 16 fish, 17 cephalopods and 1 crustacean. The stabilization of the food items richness was attained at 35 food items and 104 stomachs, approximately. A remarkable predation upon the flying fish Cheilopogon cyanopterus was observed around SPSPA, directly related to the main reproductive period of this species in the area. The oilfish's food spectrum shows that the species feeds on a wide vertical range in the water column, catching prey items at the surface or in shallow waters, as well as epi-mesopelagic fish, in addition to mesopelagic cephalopods.

The Clinical, Roentgenological and Morphological Effects of an Acute Exposure of Phosgene on the Lungs of Dogs

1971 ◽  
Vol 29 ◽  
pp. 236-237
Author(s):  
R. F. Bils ◽  
W. F. Diller ◽  
F. Huth
Keyword(s):  
Latent Period ◽  
Chemical Industry ◽  
Toxic Substance ◽  
Lung Edema ◽  
X Rays ◽  
Beagle Dogs ◽  
Male And Female ◽  
Morphological Alterations ◽  
Before And After ◽  
Electron Microscopes

Phosgene still plays an important role as a toxic substance in the chemical industry. Thiess (1968) recently reported observations on numerous cases of phosgene poisoning. A serious difficulty in the clinical handling of phosgene poisoning cases is a relatively long latent period, up to 12 hours, with no obvious signs of severity. At about 12 hours heavy lung edema appears suddenly, however changes can be seen in routine X-rays taken after only a few hours' exposure (Diller et al., 1969). This study was undertaken to correlate these early changes seen by the roengenologist with morphological alterations in the lungs seen in the'light and electron microscopes.Forty-two adult male and female Beagle dogs were selected for these exposure experiments. Treated animals were exposed to 94.5-107-5 ppm phosgene for 10 min. in a 15 m3 chamber. Roentgenograms were made of the thorax of each animal before and after exposure, up to 24 hrs.

Ultrastructural investigation of spontaneous pituitary gonadotroph cell adenomas in aging Sprague-Dawley rats

1983 ◽  
Vol 41 ◽  
pp. 702-703
Author(s):  
D. J. McComb ◽  
J. Beri ◽  
F. Zak ◽  
K. Kovacs
Keyword(s):  
Electron Microscopy ◽  
Animal Model ◽  
Epoxy Resin ◽  
Immunoelectron Microscopy ◽  
Tumor Type ◽  
Gonadal Function ◽  
Sprague Dawley ◽  
Male And Female ◽  
Reticulin Fibers ◽  
Sprague Dawley Rats

Gonadotroph cell adenomas of the pituitary are infrequent in human patients and are not invariably associated with altered gonadal function. To date, no animal model of this tumor type exists. Herein, we describe spontaneous gonadotroph cell adenomas in old male and female Sprague-Dawley rats by histology, immunocytology and electron microscopy.The material consisted of the pituitaries of 27 male and 38 female Sprague Dawley rats, all 26 months of age or older, removed at routine autopsy. Sections of formal in-fixed, paraffin-embedded tissue were stained with hematoxylin-phloxine-saffron (HPS), the PAS method and the Gordon-Sweet technique for the demonstration of reticulin fibers. For immunostaining, sections were exposed to anti-rat β-LH, anti-ratβ-TSH, anti-rat PRL, anti-rat GH and anti-rat ACTH 1-39. For electron microscopy, tissue was fixed in 2.5% glutaraldehyde, postfixed in 1% OsO4 and embedded in epoxy-resin. Tissue fixed in 10% formalin, embedded in epoxy resin without osmification, was used for immunoelectron microscopy.

Quantitative ultrastructural reconstruction of small regions within large volumes by correlative light and high voltage electron microscopy of serial 0.25-0.50 μm sections

1987 ◽  
Vol 45 ◽  
pp. 578-581
Author(s):  
Conly L. Rieder ◽  
Frederick J. Miller ◽  
Edwin Davison ◽  
Samuel S. Bowser ◽  
Kirsten Lewis ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Mitotic Spindle ◽  
Meiotic Spindle ◽  
High Voltage Electron Microscopy ◽  
Male And Female ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Differential Stability ◽  
Sperm Aster

In this abstract we Illustrate how same-section correlative light and high voltage electron microscopy (HVEM) of serial 0.25-0.50-μm sections can answer questions which are difficult to approach by EM of 60-100 nm sections.Starfish (Pisaster and Asterlas) eggs are fertilized at meiosis I when the oocyte contains two maternal centrosomes (e.g., asters) which form the poles of the first meiotic spindle. Immediately after fertilization a sperm aster is assembled in the vicinity of the male pronucleus and persists throughout meiosis. At syngamy the sperm aster splits to form the poles of the first mitotic spindle. During this time the functional and replicative properties of the maternal centrosome, inherited from the last meiotic division, are lost. The basis for this differential stability, of male and female centrosomes in the same cytoplasm, is a mystery.

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