Search results for "Sexual maturity"

Hydrolytic enzymes in the coelomic cells of the polychaeteNereis virens during sexual maturation

1991

Nereis virens were collected between April 1989 and April 1990 at Yerseke, Oosterscheldt Bay, The Netherlands. Activities of the hydrolytic enzymes arylsulfatase, acid phosphatase, N-acetylglucosaminidase, aminopeptidase, and carboxylesterase were investigated in coelomic cells (elaeocytes) of individuals at different stages of maturation as determined by the time course of oocyte growth. On a protein-content basis, up to ten-fold higher specific activities were present in the elaeocytes compared to the body-wall tissue. Acid phosphatase, N-acetylglucosaminidase, leucine aminopeptidase, and long- and medium-chain esterase increased continuously from the beginning to the later stage of sexua…

Characterization of two male-specific polypeptides in the tergal glands secretions of the cockroach Leucophaea maderae (Dictyoptera, Blaberidae)

1998

0965-1748 (Print) Journal Article Research Support, Non-U.S. Gov't; During the sexual behavior of cockroaches, the female mounts the courting male to feed on the proteinaceous secretion of the tergal glands. Polyacrylamide gel electrophoresis of male and female protein extracts after cuticle wiping revealed three major bands. Two of 18 and 22 kDa, named Lma-P18 and Lma-P22, are specific to the male tergal extracts. Moreover, Lma-P22 is only found in the male second tergite extracts. The third one of 54 kDa, named Lma-P54, is common to male and female extracts and could be considered as an ubiquitous surface protein. Several other minor proteins are also present on the body surface of adults…

Increased Parasite Abundance Associated with Reproductive Maturity of the Clam Anodonta piscinalis

1999

Several studies on vertebrates have demonstrated that reproductive activities may increase the parasite load, but this has not been shown in invertebrate hosts. We studied abundance of a potentially harmful gill parasite, the ergasilid copepod Paraergasilus rylovi, from the freshwater bivalve host Anodonta piscinalis in relation to reproductive maturity of the host in the field. Prevalence of this previously unstudied parasite varied from 90 to 100%, and the mean parasite abundance from 16.3 to 28.8 among 3 study populations. Abundance of P. rylovi increased with host size. In the maturating age groups (3-5 yr) the length-adjusted mean parasite abundance among mature, reproducing female cla…

Parental experience of a risky environment leads to improved offspring growth rate.

2014

Abstract Parasites (or diseases) are major selective force for the evolution of life history traits and parasite-host evolution. Mothers can show a variety of responses to parasites during pregnancy with different consequences for them or their offspring. However, whether information in the maternal environment before pregnancy can cause a change in the phenotype of the offspring is unknown. To avoid the confounding effect of pathogens and to reduce the risk of direct effect of mother's immune activation, we injected female laboratory mice with lipopolysaccharides (LPS) before mating. In order to provide a constant information on the potential infectious risk of the environment, females wer…

Prospero mutants induce precocious sexual behavior in Drosophila males.

2007

0001-8244 (Print) Journal Article Research Support, Non-U.S. Gov't; Brain maturation, a developmental process influenced by both endogenous and environmental factors, can affect sexual behavior. In vertebrates and invertebrates, sexual maturation is under the influence of hormones and neuromodulators, but the role of developmental genes in this process is still poorly understood. We report that prospero (pros), a gene crucial for nervous system development, can change the age of onset of sexual behavior in Drosophila melanogaster males: adult males carrying a single copy of several pros mutations court females and mate at a younger age than control males. However, these pros mutations had n…

Corynosoma cetaceumin the Stomach of Franciscanas,Pontoporia blainvillei(Cetacea): an Exceptional Case of Habitat Selection by an Acanthocephalan

2001

Adult acanthocephalans are typically found in the intestine of vertebrates, where they can readily absorb nutrients. However, Corynosoma cetaceum has been frequently reported in the stomach of cetaceans from the Southern Hemisphere. The ecological significance of this habitat was investigated by examining data on number, sex ratio, maturity status, biomass, and fecundity of C. cetaceum in different parts of the digestive tract of 44 franciscanas Pontoporia blainvillei. Individual C. cetaceum occurred in the pyloric stomach (PS) and, to lesser degrees, in the duodenal ampulla (DA) and the main stomach (MS). Females outnumbered males in all chambers, although the sex ratio was closer to 1:1 i…

2013

Information on aging, maturation, and growth is important for understanding life histories of organisms. In extinct dinosaurs, such information can be derived from the histological growth record preserved in the mid-shaft cortex of long bones. Here, we construct growth models to estimate ages at death, ages at sexual maturity, ages at which individuals were fully-grown, and maximum growth rates from the growth record preserved in long bones of six sauropod dinosaur individuals (one indeterminate mamenchisaurid, two Apatosaurus sp., two indeterminate diplodocids, and one Camarasaurus sp.) and one basal sauropodomorph dinosaur individual (Plateosaurus engelhardti). Using these estimates, we e…

PERTUMBUHAN, UMUR, DAN DIMORFISME SEKSUAL IKAN PELANGI ARFAK, Melanotaenia arfakensis Allen, 1990 DI SISTEM SUNGAI PRAFI, MANOKWARI, PAPUA BARAT

2018

ABSTRACTArfak rainbow fish, Melanotaenia arfakensis is an endemic fish on several river systems in the northeastern part of the Vogelkop peninsula. This study aims to describe the growth, age at first maturity, and sexual dimorphism of this endemic fish on the Nimbai Stream and the Aimasi Stream, the Prafi River system. The fish were caught using handnet, then were measured their standard length and individual weight. Data were analyzed to estimated growth patterns, von Bertalanffy's growth rate, age at first maturity and sexual dimorphism characteristics. The results showed that male growth patterns varied, with a tendency of the increase in body length faster than that of body weight (neg…

Emergence of the epibiotic barnacle Xenobalanus globicipitis in Guiana dolphins after a morbillivirus outbreak in Sepetiba Bay, Brazil

2021

Abstract We report on the emergence of the epibiotic barnacle Xenobalanus globicipitis in Guiana dolphins (Sotalia guianensis) from Sepetiba Bay, Rio de Janeiro, Brazil, in September 2018, six months after a lethal morbillivirus epidemic. Small boat surveys were conducted at the entrance and in the interior of the bay from January 2018 to February 2021. Dolphins were photo-identified and classified according to overall spatial use of the Bay. We examined the potential influence of the period and habitat on the prevalence of X. globicipitis. The overall prevalence of the barnacle was 38.7% in 214 dolphins. X. globicipitis was not observed in 99 individually identified dolphins from January t…

Distribution and biology of the Blackmouth catshark Galeus melastomus in the Strait of Sicily (Central Mediterranean Sea)

2009

The Blackmouth catshark, Galeus melastomus, Rafinesque, 1810 (Carcharhiniformes; Scyliorhinidae), is a common, although at present discarded, by- catch of the bottom trawl fisheries in the Strait of Sicily. Given its ecological interest, data gathered in experimental bottom trawl surveys were analysed in order to describe its distribution and main biological traits. The Blackmouth catshark was sampled almost exclusively on the upper slope (200-800), showing the highest frequency of occurrence (69-100%), biomass (BI; 10-85 kg*km-2) and density (DI; 54-506 N*km-2) indexes in the deeper (501-800m) grounds. Individual size (total length, TL, mm) were between 70-590 and 90-510 in females and mal…