Neurotrophins and specific receptors in the oviduct tracts of Japanese quail ( Coturnix coturnix japonica )

Growing and laying performance of two different-plumage color Japanese quail varieties supplemented with corn silk in their diet

The current study aimed to investigate the dietary supplementation effect of corn silk (CS) on performance and blood chemistry of brown and white-feathered quails during the grower and layer periods. Japanese quails of brown and white-feathered color (180 birds/variety at 2 wks old) were randomly allotted into three groups with 3 replicates each (n = 20 birds/replicate). Corn silk powder (CS) was supplemented to the basal diet at 0, 1, and 2% of the diet for each quail variety for 1-month growing period, then continued for another 6-wk laying period to assess the egg production and egg quality characteristics. CS supplementation at 1% and 2% for brown and white-feathered quails respectively improved their growth performance (body weight and weight gain), carcass yield, and intestinal villi length with increasing feed consumption but without changes in feed conversion ratio. In both quail varieties, CS addition had a hypolipidemic effect, confirmed by lowering serum triglyceride (TG), cholesterol (CHO), and low density lipoprotein (LDL) while increased high density lipoprotein (HDL) concentrations (P < 0.05) with a clear response observed in white quails than the brown ones. Besides, CS supplementation increased (P = 0.002) hen day egg production in brown feathered quails, while reducing it in the white-feathered quails compared with the CS-free diet. The increased egg production was not significantly (P > 0.05) correlated with lower content of TG and CHO, while significantly increased the antioxidant content in both quail varieties (P < 0.05). Moreover, CS dietary supplementation significantly enhanced (P = 0.003) the yolk color, especially in brown-feathered quail. In conclusion, CS can be safely supplemented to the Japanese quail diet (1% and 2% for brown-feathered and white-feathered quails respectively) to improve growth performance, and egg quality characteristics.

Influences of Dietary Supplementation with Maca (Lepidium meyenii) on Performance, Parameters of Growth Curve and Carcass Characteristics in Japanese Quail

Simple Summary

It is known that the bioactive compounds (N-benzyl-palmitamide, benzyl isothiocyanate, glucosinolates and phenolics) in the maca plant are appetizing, as well as having antioxidant effects and improving reproductive ability. The aim of this study was to determine the effects of adding maca plant powder to the ration at different levels on growth, slaughter carcass, partial egg production and some reproductive characteristics of Japanese quail (Coturnix coturnix japonica). Addition of maca powder to the diet increased the feed consumption but did not affect growth, slaughter carcass, partial egg production or fertility. In addition, maca powder reduced embryonic deaths and improved chick quality. According to these results, the positive effects of short-term application of maca powder are not observed during the fattening period in Japanese quails.

Abstract

Maca plant contains rich nutrients and in addition, it has various bioactive substances (N-benzyl-palmitamide, benzyl isothiocyanate, glucosinolates and phenolics). It is used to improve reproductive properties and has antioxidant effects for both humans and animals. The aim of this study was to determine the effects of adding maca plant powder to the ration at different levels on growth, slaughter carcass, partial egg production and some reproductive characteristics in Japanese quail (Coturnix coturnix japonica). The experimental groups were formed by adding 0% (control), 0.05% and 0.1% maca powder to the diet, and a total of 300 birds were used. Growth (weekly body weights, parameters of Gompertz growth function), feed efficiency and carcass characteristics of quails in the 42-day fattening trial were determined. Reproductive characteristics were measured up to 22 weeks of age. Addition of maca powder to the diet increased the feed consumption (p < 0.05) but did not affect body weights at 35 and 42 days of age, β₀ and β₁ parameters or point of inflection weight of the Gompertz model, carcass traits, partial egg production or fertility. It may be advisable to add 0.1% maca powder to the diets of breeders. Besides, maca powder reduced embryonic deaths and improved chick quality (both p < 0.05). It is thought that different results for reproductive traits can be obtained if maca powder is used for a longer period in the diets of breeder quail flocks.

An evo-devo perspective of the female reproductive tract

The vertebrate female reproductive tract has undergone considerable diversification over evolution, having become physiologically adapted to different reproductive strategies. This review considers the female reproductive tract from the perspective of evolutionary developmental biology (evo-devo). Very little is known about how the evolution of this organ system has been driven at the molecular level. In most vertebrates, the female reproductive tract develops from paired embryonic tubes, the Müllerian ducts. We propose that formation of the Müllerian duct is a conserved process that has involved co-option of genes and molecular pathways involved in tubulogenesis in the adjacent mesonephric kidney and Wolffian duct. Downstream of this conservation, genetic regulatory divergence has occurred, generating diversity in duct structure. Plasticity of the Hox gene code and wnt signaling, in particular, may underlie morphological variation of the uterus in mammals, and evolution of the vagina. This developmental plasticity in Hox and Wnt activity may also apply to other vertebrates, generating the morphological diversity of female reproductive tracts evident today.

Effect of mating on mRNA and protein expression of beta nerve growth factor and its receptor, TrKA, in the oviduct of llama (Lama glama)

Copulation produces different stimuli in the female reproductive tract in camelids, which lead to ovulation. Expression of β-nerve growth factor (β-NGF) and its specific receptor, tropomyosin receptor kinase A (TrKA), was studied comparing the oviductal microenvironment of mated and nonmated llamas. β-NGF and TrKA were expressed in the llama ampulla, isthmus, and utero-tubal-junction (UTJ), and they were mainly colocalized in the apical region of the oviductal mucosa. A TrKA immunosignal was also found in muscle cells and blood vessels, with the highest mark in UTJ muscle cells of copulated females. Both β-NGF and TrKA transcripts were expressed in the three oviductal segments. Relative TrKA abundance did not differ between mated and nonmated females, but relative β-NGF abundance was higher in the UTJ of copulated females (p < .05). β-NGF might not be secreted into the oviductal fluid (OF) since the protein was not found in the OF of mated or nonmated females. Therefore, it can be concluded that the llama oviduct expresses the β-NGF/TrKA system and that an increase in β-NGF gene expression in the UTJ 24 h after copulation along with an increase in TrKA protein expression may indicate an important role in the gamete transport and fertilization process in llamas.

Role of nerve growth factor in the reproductive physiology of female rabbits: A review

Rabbit does are reflex ovulators such that coitus is needed to release GnRH and elicit the LH surge that triggers the ovulation of mature oocytes. However, the mechanisms eliciting ovulation in this species remain unclear. One of the most promising recently discovered candidates with a role in female reproductive physiology is nerve growth factor beta (β-NGF). This neurotrophin and its high-affinity receptor TrkA and low affinity receptor p75, is present in all compartments of the ovary, oviduct and uterus suggesting a physiologic role in ovarian folliculogenesis, steroidogenesis, ovulation, luteogenesis and embryo development. Besides, evidence exists that β-NGF found in seminal plasma could exert a modulatory role in the female hypothalamus-pituitary-ovarian axis contributing to the adrenergic and cholinergic neuronal stimulus of GnRH neurons in an endocrine manner during natural mating. Probably, the paracrine and local roles of the neurotrophin in steroidogenesis and ovulation reinforce the neuroendocrine pathway that leads to ovulation. This review updates knowledge of the role of β-NGF in rabbit reproduction, including its possible contribution to the mechanisms of action that induce ovulation, and discusses perspectives for the future applications of this neurotrophin on rabbit farms.

Neurotrophins and Trk receptors in the developing and adult ovary of Coturnix coturnix japonica

NGF, BDNF, NT-3 and their specific receptors TrkA, TrkB and TrkC are known to be involved in the development and maintenance of vertebrates' nervous system. However, these molecules play a role also in non-neuronal tissue, such as in the reproductive system. In this study we investigated the presence and localization of neurotrophins and Trk receptors to unravel their potential role in the developing and adult ovary of Japanese quail, a model species well suited for reproduction studies. Western blotting analysis on ovaries of three month old quails in the period of egg laying showed the presence of pro and mature forms of neurotrophins and splice variants of Trk receptors. Immunohistochemical investigation reported that in embryonic ovaries from the 9th day of incubation to the hatching NGF and NT-3 were observed in the cortical and medullar areas respectively, whereas Trk receptors were observed in both areas. In adult ovary, all NTs were detected in glandular stromal cells, NGF and NT-3 also in the nervous component. Regarding follicle components, NGF and BDNF were observed in oocytes and follicular cells. All TrK receptors were present in nervous components and only TrkA in glandular stromal cells. In follicles, TrkA was present in oocyte cytoplasm and TrkB in theca cells. The results suggest an involvement of the neurotrophin system in the quail ovary physiology, promoting the oocyte development and follicular organization in the embryo, as well as oocyte and follicular maturation in adults.

Morpho-Functional Features of the Gonads of Danio rerio: the Role of Brain-Derived Neurotrophic Factor

Zebrafish, a suitable and widely used teleost fish model in basic biomedical research, displays morphophysiological features of adult gonads that share some commonalities with those of mammalian species. In mammals, gametogenesis is regulated, among several factors, by brain-derived neurotrophic factor (BDNF). This neurotrophin has a well-established role in the developing and adult nervous system, as well as gonads development and functions in vertebrate species. We hypothesize that BDNF has a role also in the gonadal functions of zebrafish. At this purpose, we investigated BDNF and its receptors p75 and TrkB in the ovary and testis of adult zebrafish, kept under laboratory conditions. Our results display (1) the expression of BDNF mRNA and pro-BDNF protein outside of the nervous system, specifically in the ovary and testis; (2) the presence of pro-BDNF in primary oocytes and follicular layer, and p75 in follicular cells; (3) the localization of pro-BDNF in type B spermatogonia, and Sertoli cells in testis. Altogether, these data lead us to consider that BDNF is involved in the gonadal function of adult zebrafish, and mainly in the adult ovary. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:140-147, 2018. © 2017 Wiley Periodicals, Inc.