Title Hormonski nadzor nad razvojem spolnog sustava i proizvodnjom jaja u ptica Title (english) Hormonal Control of Reproductive System Development and Egg Production in Birds Author Stjepan Jelečanin Mentor Jasna Aladrović (mentor)Mentor Lana Pađen (mentor)Committee member Željko Gottstein (predsjednik povjerenstva)Committee member Jasna Aladrović (član povjerenstva)Committee member Lana Pađen (član povjerenstva)Granter University of Zagreb Defense date and country 2025-02-18, Croatia Scientific / art field, BIOMEDICINE AND HEALTHCARE Abstract Spolne žlijezde, jajnik u ženki i testisi u mužjaka, proizvode spolne stanice. Jajne stanice se
proizvode procesom koji nazivamo oogeneza, a spermiji u testisima spermatogenezom. Za
pravilno funkcioniranje reproduktivnog ciklusa u ptica, potreban je pravilan embrionalni razvoj
te spolna diferencijacija. Spolni sustav ženki ptica, jajnik, jajovod, uterus i kloaka, kao i spolni
sustav mužjaka ptica, testisi, epididimis, sjemenovod, kloaka i akcesorne spolne žlijezde
razvijaju se i
... More funkcioniraju pod djelovanjem hormona. Hormoni koji se proizvode u endokrinim
žlijezdama ženki ptica od važnosti za su reproduktivni ciklus: od sazrijevanja spolnog sustava,
razvoja folikula na jajnicima, ovulacije, sinteze bjelančevina, sinteze ljuske jajeta i konačno do
polaganja oplođenog ili neoplođenog jajeta. Reproduktivni ciklus kontroliran je zajedničkim
djelovanjem osi hipotalamus- hipofiza-gonade. Glavni hormoni koje luči hipofiza su
gonadotropini, luteinizacijski hormon (LH) i folikulostimulacijski hormon (FSH). Ključna
uloga LH-a je indukcija ovulacije, a u mužjaka stimulaciju Leydigovih stanica na
diferencijaciju i posljedičnu proizvodnju testosterona. Hormon FSH-a utječe na rast folikula i
razvoj dominantnog preovulatornog folikula, dok je u mužjaka ptica, glavni zadatak FSH-a
stimulacija spermatogeneze. Prolaktin djeluje na ponašanje prilikom inkubacije jaja kao i na
pojavu nagona za izradu i označavanje gnijezda i posljedičnog sjedenja na jajima. Glavni
hormoni jajnika su estrogeni i progesteron. Estrogeni su većinom proizvedeni u teka stanicama
i odgovorni za razvoj i održavanje ženskih spolnih organa i sekundarnih spolnih obilježja.
Progesteron, proizveden u granuloza stanicama većih folikula, potiče rast spolnih organa i
funkcije gonada, sprječava razvoja dodatnih preovulatornih folikula, koči pojave znakova
seksualnog ponašanja. Najvažniji androgeni hormon je testosteron, kojeg proizvode Leydigove
stanice. Testosteron potiče proizvodnju spermija, razvoj spolnih obilježja mužjaka i rast kostiju
i muskulature, a utječe i na spolni nagon mužjaka. Gotovo sva djelovanja testosterona u
konačnici su usmjerena na polaganje spermija u ženku. Razumijevanje hormonalnih
mehanizama i fiziologije reprodukcije ptica omogućuje optimizaciju reprodukcijskog
potencijala, povećanje produktivnosti i unapređenje upravljanja zdravljem nesilica Less Abstract (english) The gonads, the ovary in the female and the testes in the male produce gametes. Egg cells are
produced by oogenesis in the ovary and sperm cells by spermatogenesis in the testicles. For the
reproductive cycle in birds to function properly, proper embryonic development and sexual
differentiation are required. The reproductive system of female birds, the ovary, oviduct, uterus
and cloaca, as well as the reproductive system of male birds, the testes, epididymis, vas
deferens,
... More cloaca and accessory sex glands, develop and function under the influence of
hormones. Hormones produces in endocrine glands are important for the reproductive cycle:
from the maturation of the reproductive system, the development of follicles in the ovaries,
ovulation, protein synthesis, eggshell synthesis and finally to the laying of a fertilized or
unfertilized egg. The reproductive cycle is controlled by the joint action of the hypothalamicpituitary-gonadal axis. The main hormones secreted by the pituitary gland are gonadotropins,
luteinizing hormone (LH) and follicle-stimulating hormone (FSH). The key role of LH is the
induction of ovulation, and in males, the stimulation of Leydig cells to differentiate and
subsequently produce testosterone. FSH affects the growth of follicles and development of
dominant preovulatory follicle, while in male birds, the main task of FSH is to stimulate
spermatogenesis. The main roles of prolactin are to influence the behavior during egg
incubation as well as the emergence of the instinct to build and mark the nest and the subsequent
sitting on the eggs. The main ovarian hormones are estrogens and progesteron.Estrogenes are
mostly produced in theca cells and responsible for the development and maintenance of female
genital organs and secondary sexual characteristics, Progesterone, produced in the granulosa
cells of larger follicles, whose most important effects are to stimulate the growth of the genital
organs and gonadal function, prevent the development of additional preovulatory follicles, and
inhibit the appearance of signs of sexual behavior. The most important androgenic hormone is
testosterone, produced by Leydig cells. Testosterone stimulates sperm production, the
development of male sexual characteristics, and the growth of bone and muscle and also
influences psychological development and male sexual drive. Understanding the hormonal
mechanisms and physiology of birds allows for the optimization of reproductive potential,
increased productivity, and improved health management of laying hens Less Keywords
reprodukcijski sustav ptica
hormonska regulacija
os hipotalamus-hipofizaspolne žlijezde
ovulacija
ovipozicija
inkubacija
Keywords (english)
avian reproductive system
hormonal regulation
hypothalamic-pituitary-gonadal axis
ovulation
oviposition
egg incubation
Language croatian URN:NBN urn:nbn:hr:178:750211 Study programme Title: Veterinary Medicine Type of resource Text File origin Born digital Access conditions Open access Terms of use Created on 2025-03-03 08:45:12
