Quercetin directly promotes rabbit ovarian steroidogenesis

[EN] The bioflavonoid quercetin is a component of food with numerous biological effects, but its function in reproductive processes remains to be investigated. This study aimed to examine the direct action of quercetin on steroid hormone release in rabbit ovaries. We analysed the effect of quercetin (0, 1, 10, and 100 ng/mL) on cultured rabbit ovarian fragments. The release of progesterone (P4), testosterone (T) and estradiol (E2) were analysed by enzyme immunoassay. Quercetin promoted P4, T, and E2 release by rabbit ovarian fragments. These observations indicate that quercetin can directly stimulate rabbit ovarian steroidogenesis – an essential regulator of reproduction and fecundity. The application of dietary quercetin for control of rabbit reproduction is discussed.Sirotkin, A.; Štochmaľová, A.; Grossmann, R.; Alwasel, S.; Harrath, A. (2019). Quercetin directly promotes rabbit ovarian steroidogenesis. 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The first subterranean freshwater planarians from North Africa, with an analysis of adenodactyl structure in the genus Dendrocoelum (Platyhelminthes, Tricladida, Dendrocoelidae)

The paper describes the first species of freshwater planarians collected from subterranean localities in northern Africa, represented by three new species of Dendrocoelum Örsted, 1844 from Tunisian springs. Each of the new species possesses a well-developed adenodactyl, resembling similar structures in other species of Dendrocoelum, notably those from southeastern Europe. Comparative studies revealed previously unreported details and variability in the anatomy of these structures, particularly in the composition of the musculature. An account of this variability is provided, and it is argued that the anatomical structure of adenodactyls may provide useful taxonomic information

First report of adelphophagy in flatworms during the embryonic development of the planarian Schmidtea mediterranea (Benazzi, Baguñà, Ballester, Puccinelli & Del Papa, 1975) (Platyhelminthes, Tricladida)

This paper details the embryonic development of the triclad flatworm Schmidtea mediterranea and describes, for the first time in flatworms, the phenomenon of adelphophagy. Embryonic development, which takes 23 days at 18-20°C, basically corresponds with the developmental stages documented in other studies for triclad flatworms. At some of the stages it was observed occasionally that some embryos cannibalized their siblings, i.e. exhibited adelphophagy or embryophagy. It is suggested that this phenomenon may contribute to the fact that the number of young hatching from a cocoon is usually considerably less than the number of egg cells initially assembled in the capsule. The occurrence of adelphophagy in the animal kingdom is discussed

The first subterranean freshwater planarians from North Africa, with an analysis of adenodactyl structure in the genus Dendrocoelum (Platyhelminthes, Tricladida, Dendrocoelidae).

The paper describes the first species of freshwater planarians collected from subterranean localities in northern Africa, represented by three new species of Dendrocoelum Örsted, 1844 from Tunisian springs. Each of the new species possesses a well-developed adenodactyl, resembling similar structures in other species of Dendrocoelum, notably those from southeastern Europe. Comparative studies revealed previously unreported details and variability in the anatomy of these structures, particularly in the composition of the musculature. An account of this variability is provided, and it is argued that the anatomical structure of adenodactyls may provide useful taxonomic information

Freshwater planarians (Platyhelminthes, Tricladida) from the Palearctic section of the African continent: new records, with the description of a new species

On the basis of extensive surveys, an update is provided on the diversity, taxonomy, anatomy, and geographic distribution of five species of North African freshwater planarians, including the description of one new species. The new species Dugesia tubqalis Harrath & Sluys, sp. nov. is mainly characterized by the following features: an elongated penis surrounded with two penial folds at its base, the dorsal one bigger than the ventral ; an atrium divided into a male and common atrium by a kind of non-muscular ridge; a terminal expansion of the ejaculatory duct just before it opens at the tip of the penis papilla. The record of Dugesia sicula represents the first fully documented record of a naturally sexual, diploid (2n=18) population in North Africa. The first finding of Polycelis nigra on the African continent is documented. The genus Polycelis is recorded here with two species, Polycelis nigra and Polycelis felina. We also noted the presence of Schmidtea polychroa, which is widespread in Europe and introduced in North America

Sex differences in regional specialisation across the placental surface

There may be regional specialisation in structure and function across the placental surface. In Riyadh, Saudi Arabia, the length and the breadth of the placental surface at birth were highly correlated, but the breadth was more closely associated with the size of the baby. To replicate this we studied 321 pregnant Saudi women in the town of Baish. We measured the size of the newborn babies and their placentas.The association of the length and breadth of the placental surface on the baby's body size differed in boys and girls. Among boys the breadth had a stronger association with all birth measurements except crown–heel length. This was similar to the findings in Riyadh. Placental surface length was related to crown–heel length. For each centimetre in surface length, crown–heel length increased by 0.27 cm (95% CI 0.09–0.44, p = 0.004). Among girls placental surface breadth was related to crown–heel length, whereas surface length was related to birth weight, head and thigh circumferences. For each centimetre in surface breadth, crown–heel length increased by 0.33 cm (0.13–0.53, p = 0.001).We conclude that, within Saudi Arabia, there are both geographical and sex differences in regional specialisation across the placental surface. In the adverse circumstances of Baish, linked to the mothers' short stature, boys were smaller at birth than girls. Boys may have compensated for under-nutrition by increasing the depth of spiral artery invasion rather than by recruiting additional spiral arteries. Girls may have had more effective regional specialisation across the placental surfac