The European beaver (Castor fiber L.) is an important free-living rodent that inhabits Eurasian temperate forests. Beavers are often referred to as ecosystem engineers because they create or change existing habitats, enhance biodiversity and prepare the environment for diverse plant and animal species. Beavers are protected in most European Union countries, but their genomic background remains ...

This study was aimed to evaluate the effect of GnRH injection on semen ejaculate characteristics in Awassi rams collected in breeding and non breeding seasons. The study was conducted in late summer to early autumn when breeding activity commences, and in winter during the non breeding season. Twelve mature Awassi rams were used in this study. Animals were randomly allocated into two equal grou...

pregnancy rate is one of the most important factors determining profit or loss. Considerable emphasis and focus is placed on the nutritional and reproductive management of the cow herd; but, unfortunately, in most operations little emphasis is placed on the bull. However, each bull is expected to impregnate from 15 40 females during the breeding season in a typical cow-calf operation and, thus,...

The seminal vesicles of adult sand rat contain a major secretory protein band (MW 21 kDa) designated as Psammomys obesus seminal vesicles protein of 21 kDa (POSVP(21)). This protein is abundant in secretions, regulated by androgens and also present in the vaginal plug. POSVP(21) accounts for over 22.3% of soluble proteins from homogenate during the breeding season, 13.3% during the middle seaso...

Territorial behavior of the orange-tufted sunbird (Nectarinia osea Bonaparte) was studied in a suburb of Tel Aviv. Both male and female orange-tufted sunbirds occupied and guarded their territory throughout the year, but did so at different intensities in relation to season and fertility stages. When they were in the territory, both sexes spent most of their time at its center, and more so duri...

Effects of Body Condition Recent University of Arkansas research determined the interactive effects of forage environment and body condition on the calving rate of beef cows. multiparous beef cows (1/4 to 3/8 Brahman) were managed to achieve marginal (4.7) or good (6.6) body condition scores (BCS) over approximately 5 months before the initiation of the breeding season. growth, endophyte acres ...

The aim of the present study was to elucidate the regulatory role of cell proliferation and apoptosis in testicular development of wild Daurian ground squirrels during the breeding season (April), the non-breeding season (June) and before hibernation (September). Gross mass and hormonal analysis showed that the testis:body mass ratio and plasma testosterone concentration fluctuated seasonally, ...

The aim of this study was to investigate the seasonal expression of androgen receptor (AR), estrogen receptors α and β (ERα and ERβ) and aromatase cytochrome P450 (P450arom) mRNA and protein by real-time PCR and immunohistochemistry in the wild ground squirrel (WGS) testes. Histologically, all types of spermatogenic cells including mature spermatozoa were identified in the breeding season (Apri...

In anurans, circulating levels of androgens influence certain secondary sexual characteristics that are expressed only during the breeding season. We studied the contractile properties of external oblique muscles (used to power sound production) in a species of North American gray tree frog, Hyla chrysoscelis, during the breeding season and also in testosterone-treated captive males and females...