In the breeding male, adrenal enlargement and accumulation of fine lipid droplets in early December accompanies sexual accessory organ development. In primates, reproductive synchrony usually takes the form of conception and birth seasonality. Seasonal spawning is accompanied by major metabolic and physiological changes. The following article is from The Great Soviet Encyclopedia (1979). typically are gravid in the summer months, from May through September. Offspring, especially when occurring in large numbers. In the spawning season, the number of Stilling cells remains small. The Stilling cells in some species display an annual cycle in terms of numbers and staining properties. If the problems are not addressed, disease outbreaks and mortalities often follow. Spawn is the eggs and sperm released or deposited into water by aquatic animals.As a verb, to spawn refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning.Most aquatic animals, except for aquatic mammals and reptiles, reproduce through the process of spawning.. Spawn definition: Spawn is a soft , jelly-like substance containing the eggs of fish, or of animals such as... | Meaning, pronunciation, translations and examples Most commonly, zebrafish are removed from their housing tanks and placed into off-system spawning tanks that often consist of two tanks nested together with the inside tank having holes or a screen to allow eggs to fall through to the bottom of the outer tank (Fig. The eggs of aquatic animals such as bivalve mollusks, fishes, and amphibians. 1. Adult eels make oceanic, Sneakers, Satellites, and Helpers: Parasitic and Cooperative Behavior in Fish Reproduction, Randall and Randall, 1963; Reinboth, 1973; Moyer and Shepard, 1975; Warner, Randall and Randall, 1963; Choat and Robertson, 1975; Robertson and Warner, 1978, Sperm Limitation, Gamete Competition, and Sexual Selection in External Fertilizers, General, Comparative and Clinical Endocrinology of the Adrenal Cortex, Culturing echinoderm larvae through metamorphosis, FISH MIGRATIONS | Pacific Salmon Migration: Completing the Cycle, Comparative Biochemistry and Physiology Part D: Genomics and Proteomics, Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology. Under standard laboratory conditions, fish spawn well until between 2 and 3 years of age. Spawn (biology), Spawn (disambiguation), spawn: Encyclopedia [home, info] Medicine (2 matching dictionaries) spawn : online medical dictionary [ home , info ] S.J. The motivation for migration by sockeye fry to a lake-nursery environment is to take advantage of the growth potential offered by the productive lake environment, but getting there successfully from the natal stream requires important behavioral decisions to minimize energy use and avoid predators while migrating. Selina Publishers Concise Biology for Class 8 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines. Many of these tanks have an option of a removable barrier that can be placed in the tank to separate males and females for a predetermined time period before spawning (Fig. Zebrafish breeding or spawning tanks are available in many different shapes, sizes, and designs, but all can be divided into two main categories, namely, on-system and off-system. A case in which sperm from one male collide with more virgin eggs than that from another male is not sperm competition. Masatoshi Mita, in Handbook of Hormones, 2016. Learn more. Because dams are the most visible impediment to salmon survival, getting fish around, over, or through dams has been the focus of much research. Spawning requires migrating to areas that meet specific habitat requirements (e.g., depth, substrate, temperature, and current speed) for the survival and development of eggs. By this definition, sexual selection becomes unimportant to that sex when fecundity in that sex is no longer limited by fertilization. Michael H. Schiewe, Peter Kareiva, in Encyclopedia of Biodiversity, 2001, Dams block access to spawning habitats, create reservoirs that flood spawning habitats, and may stress fish migrating through them to such a large extent that females cannot replace themselves due to depressed physiological fitness. Females can broadcast spawn, brood eggs on an external surface, or brood eggs internally (after internal fertilization). GSS initiates spawning behavior and shedding of mature gametes in both male and female starfish [2]. Find more ways to say spawned, along with related words, antonyms and example phrases at Thesaurus.com, the world's most trusted free thesaurus. spawn from late summer to late fall, depending on the run. Mycology. a male salmon in spawning livery. Detailed spawning and culturing methods are provided for the sea urchin species most commonly used in cell and developmental biology, especially the California purple sea urchin (Strongylocentrotus purpuratus) and both the Pacific and Atlantic Lytechinus spp., L. pictus and L. variegatus, respectively (see chapter “Culturing echinoderm larvae through metamorphosis” by Hodin et al., this volume). 2(C)). These characteristics suggest maximal activity, coinciding with spermiation, a maximal release of male sex hormones and a peak thyroidal activity. 2. The frequency at which laboratory zebrafish are placed in breeding tanks to be spawned is somewhat variable. Nikki L. Adams, ... Kathy R. Foltz, in Methods in Cell Biology, 2019. fish migration biology discussion. Fry and smolts usually stay in freshwater from 1 to 18 months before traveling downstream to estuaries, where they remain up to 6 months. Large teeth appear on the jaws and tongue. Thus, the action of RGP is mediated through the activation of its receptor, G-protein, and adenylyl cyclase in follicle cells. It was claimed that the adrenocortical tissue does not show any seasonal cyclical activity (for R. esculenta and R. temporaria: Radu, 1931, 1938; Beatty, 1940), but the metabolic transformations of spawning and hibernation and the osmoregulatory differences of life under aquatic or semi-arid conditions clearly require active changes in adrenocortical function. W. Hanke, in General, Comparative and Clinical Endocrinology of the Adrenal Cortex, 1978. GSS mediates oocyte maturation in starfish by acting on the ovary to produce a maturation-inducing hormone (MIH), 1-methyladenine (1-MeAde), which further induces maturation of the oocytes (E-Figure 45E.3) [9]. spawn. Most of the Strongylocentrotids prefer 12–17 °C (although Strongylocentrotus droebachiensis, a trans-polar species, requires even colder temperatures, 4–10 °C). The spawning migration of adults were observed by biotelemetry techniques revealing that they exhibited diel vertical migrations in deeper water during the day and shallower water at night at the swimming speeds from 3 to 47 km/day (Righton et al., 2016). However, RGP failed to induce 1-MeAde and cAMP production in follicle cells of Patiria pectinifera ovaries during oogenesis (Mita, 2016). Resumption of meiosis in immature oocytes and spawning from the ovary is induced by a second mediator, maturation-inducing hormone, identified as 1-methyladenine (1-MeAde) in starfish (Kanatani et al., 1969; Kanatani, 1979, 1985) (Fig. Since only breeding animals actually enter water, it is unclear whether activation of the interrenal tissue is related to gonadal development or to osmotic balance. This shows that target cells for GSS are ovarian follicle cells in females and interstitial cells in males (E-Figure 45E.3). We use cookies to help provide and enhance our service and tailor content and ads. 2. Several physiological and behavioral adaptations facilitate this process, which vary depending upon whether the young fry move downstream or upstream to reach the nursery lake (i.e., moving with or against the water flow). These observations are thus at variance with the measured steroid dehydrogenase activity, which is maximal at breeding, but it is not known whether there is a September peak in activity. The peak activity, judged from the number of cells and their granulation, appears to lag behind that of the lipid cells in the annual cycle. Eosinophilia returns later in the season (Kucnerowicz, 1935; Lakshman, 1964; Gaudray, 1967; Nakamura, 1967; Suzuki, 1968; Sekiguchi, 1968; Varute, 1970a,b). Sockeye salmon more typically migrate to a nursery lake, unless they were spawned in a lake. (noun) In this sense, GSS is functionally identical to the vertebrate luteinizing hormone (LH), especially piscine and amphibian LHs, acting on the ovarian follicle cells to produce an MIH to induce the final maturation or meiotic resumption of the oocyte. For example, a case in which sperm from one male cannot fertilize an egg because it has already been fertilized by sperm from another male constitutes sperm competition.