Impact of organic agriculture on diversity and abundance of farmland birds in an arable landscape with hedges

A comparative study of breeding bird communities of organically and conventionally cultivated arable fields was carried out in northern Germany in 2005. The research was conducted on 40 pairs of fields (conventional/organic), which were selected with regard to similar field sizes and comparable boundary structures (particularly presence of hedges). Bird communities were solely dominated by the skylark Alauda arvensis L., which was the only frequent species on the tested pairs of fields. Diversity of farmland birds (number of species, Shannon-Index) was not affected by type of management. However, the abundance of skylarks (territories/10 ha) was significantly higher in organic than in conventional fields. As the study will be continued, the one-year findings will be verified with respect to changes of crops in rotations

Early food production in the Sahel of Burkina Faso

This paper is concerned with the transition from hunting and gathering to food production in West Africa, based on evidence from the Sahel Zone of Burkina Faso compiled by field research during the last years. Our study intends to enhance the knowledge about the West African versions of this transition, traditionally seen as one of the most fundamental changes in human prehistory. Embedded in an interregional program the Sahel Zone of Burkina Faso has proved to be one of its most unexpected examples

Ingestion of amniotic fluid enhances the facilitative effect of VTA morphine on the onset of maternal behavior in virgin rats

Previous research has shown that injection of morphine into the ventral tegmental area(VTA) facilitates the onset of maternal behavior in virgin female rats, and injection of the opioid antagonist naltrexone into the VTA disrupts the onset of maternal behavior in parturient rats. Placentophagia – ingestion of placenta and amniotic fluid, usually at parturition – modifies central opioid processes. Ingestion of the active substance in placenta and amniotic fluid, Placental Opioid-Enhancing Factor (POEF), enhances the hypoalgesic effect of centrally administered morphine, and more specifically, enhances δ- and κ-opioid-receptor-\ud mediated hypoalgesia and attenuates μ-opioid-receptor-mediated hypoalgesia. POEF (in placenta or amniotic fluid) ingestion does not, by itself, produce hypoalgesia. In the\ud present study, we tested the hypothesis that ingestion of amniotic fluid enhances the facilitative effect of opioid activity (unilateral morphine injection) in the VTA on the rate of onset of maternal behavior. Virgin female Long-Evans rats were given one intra-VTA injection of morphine sulfate (0.0, 0.01, or 0.03 μg, in saline) and an orogastric infusion of 0.25 ml amniotic fluid or saline once each day of the first three days of the 10-day testing\ud period. Subjects were continuously exposed to foster pups that were replaced every 12 h; replacement of pups was followed by a 15-min observation period. Maternal behavior\ud latency was determined by the first of two consecutive tests wherein the subject displayed pup retrieval, pup licking in the nest, and crouching over all foster pups, during the 15-min observation. We confirmed the previous finding that the VTA injection, alone, of 0.03 μg morphine shortened the latency to show maternal behavior and that 0.0 μg and 0.01 μg morphine did not. Ingestion of amniotic fluid (and therefore POEF) facilitated the onset of\ud maternal behavior in rats receiving an intra-VTA microinjection of an otherwise subthreshold dose of morphine (0.01 μg)

Brutplatzqualität unterschiedlich ökologisch bewirtschafteter Ackerfrüchte für die Feldlerche (Alauda arvensis)

Habitat quality of different arable crops for skylarks (Alauda arvensis) was analysed in a three year field study on 12 organic farms in northern Germany. Grass clover, spiked spring cereals (barley/spelt/wheat), winter wheat as well as grain legumes (including mixtures) hold constant abundances of skylarks during the whole breeding period. In spring oats, winter spelt and winter cereals with awn (barley/rye), however, skylark densities decreased during the breeding time, which might be explained by comparatively taller and/or denser vegetation structure of theses crops during June/July. Crops showed no significant differences in maximum abundances of skylarks. Concerning possible effects on breeding success, harrowing and/or hoeing of cereals and grain legumes should be completed as early as possible in spring to prevent breeding losses. Compared to cereals and grain legumes, the management of grass clover crops probably resulted in higher breeding losses due to a high intensity of mowing. While the cutting regime of grass clover used as green manure crops can be adapted to breeding phenology of skylarks, modification of cutting systems of forage crops should cause negative effects on quality of forage