Cuckoldry Incites Cannibalism: Male Fish Turn to Cannibalism When Perceived Certainty of Paternity Decreases

2007 ◽  
Vol 169 (2) ◽  
pp. 258
Author(s):  
Suzanne M. Gray ◽  
Dill ◽  
McKinnon
Keyword(s):  
Male Fish ◽  
Certainty Of Paternity

Cuckoldry Incites Cannibalism: Male Fish Turn to Cannibalism When Perceived Certainty of Paternity Decreases

2007 ◽  
Vol 169 (2) ◽  
pp. 258-263 ◽  
Author(s):  
Suzanne M. Gray ◽  
Lawrence M. Dill ◽  
Jeffrey S. McKinnon
Keyword(s):  
Male Fish ◽  
Certainty Of Paternity

Impact of Seasonal Changes on Composition of Total Lipid Content in Muscle, Liver and Testes of Freshwater Male Fish Mystus Cavasius (Ham) From Bhadra Reservoir, Shivamogga, Karnataka, India

2012 ◽  
Vol 3 (2) ◽  
pp. 540-541
Author(s):  
Ashashree H M Ashashree H M ◽  
◽  
B.Venkateshwarlu B B.Venkateshwarlu B ◽  
Sayeswara HA Sayeswara HA
Keyword(s):  
Total Lipid ◽  
Lipid Content ◽  
Seasonal Changes ◽  
Total Lipid Content ◽  
Male Fish

Infection of American smelt in Lake Ontario and Lake Erie with the microsporidian parasite Glugea hertwigi (Weissenberg)

1972 ◽  
Vol 50 (9) ◽  
pp. 1183-1188 ◽  
Author(s):  
M. Chen ◽  
G. Power
Keyword(s):  
Digestive Tract ◽  
Lake Erie ◽  
Ovarian Tissue ◽  
Lake Ontario ◽  
Parasite Load ◽  
Sexual Differences ◽  
Striking Difference ◽  
Female Fish ◽  
Microsporidian Parasite ◽  
Male Fish

In samples taken monthly throughout the year the percentage of American smelt in Lake Ontario and Lake Erie containing cysts of Glugea hertwigi was 5.2% and 62.7% respectively. Sexual differences in incidence were observed, the significance of which was uncertain as results from the two lakes were contradictory.In male fish infection was almost entirely restricted to the digestive tract with few cysts in the liver, skin, and testes. In female fish the digestive tract and ovaries were similarly infected.Seasonal fluctuations in Glugea infection were obvious and seemed correlated with the gonadal cycle. In both sexes the highest parasite load corresponded with the onset of maturation.A striking difference in fecundity between the two smelt populations was attributed to the Glugea infection. In females parasite cysts replaced ovarian tissue, causing a reduction in the number of maturing eggs.

scholarly journals Reproduction biology of Abe's flyingfish, Cheilopogon abei Parin, 1996 in Geser East Seram Strait Waters

2021 ◽  
Vol 21 (2) ◽  
pp. 167-184
Author(s):  
Friesland Tuapetel
Keyword(s):  
Fork Length ◽  
Biological Information ◽  
Female Fish ◽  
Male Fish ◽  
Gonad Maturity ◽  
Gill Net ◽  
Flying Fish ◽  
Reproduction Biology ◽  
Fish Samples ◽  
June July

Eco-biological information of Cheilopogon abei in Geser Streit is unknown. The objective of this research is to observe the sex ratio, first size maturity, gonad maturity and gonado somatic index (GSI) with fecundity of flying fish Ch abei in Geser East Seram Strait waters. Sampling was done for ten months started from February to November 2018, using gill net measuring 1.50 inch. All fish samples were measured in fork length and weighted so dissected to make observations on the level of gonad maturity and the number of eggs in female fish. A total of 682 flying fish was found during the study with a fork length range of 182.6-243.3 mm and a weight of 73.98-115.45 g. The results of the analysis showed that the proportion of the number of male fish was less than that of the female fish for almost every month of observation. The first size gonad mature of male and female is 210.5 mm and 214.1 mm FL. The gonad maturity index of male fish ranges from 0,963-7,967 and female fish ranges 1,315-8,069, the total fecundity is 2321-9438 eggs. Gonads of ripe fish in each month of observation. The spawning peak of Ch abei takes place in June-July and it is hoped that no arrests will be made in both months, to ensure the sustainability of the stock.

scholarly journals The The spawning aplication of Koi (Cyprinus carpio) using semi-natural method in Desa Perbarakan, Deli Serdang Regency

2020 ◽  
Vol 5 (2) ◽  
pp. 372-377
Author(s):  
Desrita ◽  
Vindy Rilani Manurung ◽  
Rizky Febriansyah Siregar ◽  
Rusdi Leidonald ◽  
Amanatul Fadhilah ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Cyprinus Carpio ◽  
Hormone Level ◽  
Anaesthetic Techniques ◽  
Land Area ◽  
Female Fish ◽  
Male Fish ◽  
Freshwater Aquaculture ◽  
Fish Spawning ◽  
Egg Yolks

Based on statistical analysis from Dinas Kelautan Perikanan, Deli Serdang Regency in 2018, The capacity for freshwater aquaculture output was recorded at 1328.9 tons / year with a land area of 65.9 ha , which is a problem for the aquaculture community with the decreasing quantity of seed production, limited infrastructure and development management which is still conventional in Desa Perbarakan, Deli Serdang Regency, therefore it is important to implement the required application of science and technology, namely the implementation of semi-natural methods of spawning techniques of koi fish (Cyprinus carpio). Counseling, seminars and practices are the methods of tasks carried out. Extension activities were carried out by illustrating the conceptual awareness of the development of koi fish spawning strategies, the distribution of leaflets, the application of recognition technology, as well as tools and resources, including the dose of gonadotropin hormone (GnH) in broodfish and fish anaesthetic techniques. For female fish, the injected hormone level is 0.5 ml / kg and 0.1 ml / kg for male fish. The weight of the female fish is 1 kg tancho sanke doitsu, 0.5 ml/gr, and the weight of the male fish is 1 kg. At a dose of 0.1 ml / gr and 900 g of shiro, kohaku at a level of 0.09 ml / gr. The result is that the number of eggs is estimated at 10,000, and then the eggs hatch within 2-4 days. Boiled egg yolks are fed to the eggs which hatch into the larvae, then the larvae are transferred to the nursery pon after 10 days of age.

scholarly journals Relationship between Gender and Opinion Leadership among the Fish Farmers of Chhattisgarh

2021 ◽  
Vol 57 (4) ◽  
pp. 93-96
Author(s):  
Dileshwari Ratre ◽  
S. N. Ojha ◽  
Arpita Sharma ◽  
Ramasubramanian V ◽  
Rajpal Yadav
Keyword(s):  
Gender Roles ◽  
Fish Farming ◽  
Opinion Leaders ◽  
Opinion Leadership ◽  
Family Resources ◽  
Female Fish ◽  
Male Fish ◽  
Extension Professionals

The ratio of fish farmers to fisheries extension professionals was 1:1000 which is too low. Para-extension functionaries can fill up this gap in the fisheries sector to improve the production and productivity of fishers. The opinion leaders from the local fish farmers community will help identify fish farmers who can further transfer the knowledge concerning how to fish to others through their diffusion network. This study was undertaken to analyze gender roles in fish farming and their relation with opinion leaders. It was observed that 90% of male fish farmers had control of fisheries/family resources, and 97 per cent of fish farmers were found to have contact with male opinion leaders. At the same time, 33% of female fish farmers were contacted by shelf help groups and local progressive farmers. The study shows that the opinion leaders influenced the fish farmers’ diffusion network and their knowledge about how to fish. To involve women in the fisheries sector, empower women, there is also a need to select opinion leaders preferred by women fish farmers.

scholarly journals Certainty of paternity in two coucal species with divergent sex roles: the devil takes the hindmost

2018 ◽  
Vol 18 (1) ◽  
Author(s):  
Ignas Safari ◽  
Wolfgang Goymann
Keyword(s):  
Sex Roles ◽  
The Devil ◽  
Certainty Of Paternity

Nesfatin-1-like peptide suppresses hypothalamo–pituitary–gonadal mRNAs, gonadal steroidogenesis, and oocyte maturation in fish†

2020 ◽  
Vol 103 (4) ◽  
pp. 802-816
Author(s):  
Jithine Jayakumar Rajeswari ◽  
Azadeh Hatef ◽  
Suraj Unniappan
Keyword(s):  
Oocyte Maturation ◽  
Reproductive Hormones ◽  
Reproductive Physiology ◽  
Biologically Active ◽  
Metabolic Effects ◽  
Steroidogenic Enzyme ◽  
Male Fish ◽  
Brain Aromatase ◽  
Circulating Levels ◽  
Receptor Mrnas

Abstract Nucleobindin (Nucb)-1 and Nucb2 are DNA and Ca2+ binding proteins with multiple functions in vertebrates. Prohormone convertase-mediated processing of Nucb2 results in the production of biologically active nesfatin-1. Nesfatin-1 is involved in the regulation of reproduction in many vertebrates, including fish. Our lab originally reported a nesfatin-1-like peptide (Nlp) encoded in Nucb1 that exhibits nesfatin-1-like metabolic effects. We hypothesized that Nlp has a suppressive role in the reproductive physiology of fish. In this research, whether Nlp regulates reproductive hormones and oocyte maturation in fish were determined. Single intraperitoneal (IP) injection of goldfish Nlp (50 ng/g body weight) suppressed salmon and chicken gonadotropin-releasing hormone (sgnrh and cgnrh2), gonadotropin-inhibiting hormone (gnih) and its receptor (gnihr), and kisspeptin and brain aromatase mRNA expression in the hypothalamus of both male and female goldfish. In the pituitary, Nlp decreased mRNAs encoding lhb, fshb and kisspeptin and its receptor, while a significant increase in gnih and gnihr was observed. In the gonads, lh (only in male fish) and fsh receptor mRNAs were also significantly downregulated in Nlp-injected fish. Sex-specific modulation of gnih, gnihr, and kisspeptin system in the gonads was also observed. Nlp decreased sex steroidogenic enzyme encoding mRNAs and circulating levels of testosterone and estradiol. In addition, incubation of zebrafish ovarian follicles with Nlp resulted in a reduction in oocyte maturation. These results provide evidence for a robust role for Nlp in regulating reproductive hormones in goldfish and oocyte maturation in zebrafish, and these effects resemble that of nesfatin-1.

Sign in / Sign up

Export Citation Format

Share Document