Intramagnal insemination of hens can eliminate negative influence of lipofectin on fertilising ability of spermatozoa

1. After intramagnal insemination egg production decreased drastically during the first two days and was equivalent to egg production of hens inseminated intravaginally for the remaining period of collection.

2. After magnal insemination, the fertility of eggs collected during the first week was 36.2% and only 3.6% during the second week.

3. In the case of intramagnal insemination, egg fertility in the first week was 88.1%, in the second week 81.8% and the third week 52.3%.

4. The eggs laid during the first day after intramagnal insemination were 83.3% fertile, indicating that treated spermatozoa fertilised the newly ovulated egg within 20 minutes of ovulation.     

Genetic Variation and Population Structure of the Grape Powdery Mildew Fungus, <Emphasis Type="Italic">Erysiphe necator</Emphasis>, in Southern France

Erysiphe necator, the causative agent of powdery mildew in grapevine, was introduced into Europe from North America during the middle of the 19th century. Our objective was to analyze the genetic variation and the population structure of the fungus in southern France. The sample comprised 101 isolates and was mainly of flag shoot origin, i.e., infection of sprouting shoots after overwintering of mycelium in buds. RAPD analysis identified different haplotypes that clustered in two genetic groups (A and B). The most frequent haplotypes of each group were found in several different locations in two areas separated by 100 km and throughout the 3 year period. Several haplotypes of both groups originated from flag shoots and were recovered over successive years indicating that there is no correlation between genetic group and overwintering mode. All isolates of group A were of mating type +, but those in group B could be either + or −. Lower genotypic diversity was detected within group A than within group B. These results were consistent with the hypothesis that group A reproduces only asexually.     

Rhabdomyosarcoma in a ferret (Mustela putorius furo)

A 5-year-old spayed male ferret showed a subcutaneous mass in the right lateral thoracic wall. Microscopic examination revealed that the neoplasm had proliferated in the subcutis with infiltration into the surrounding tissues. A packed bundle of large polymorphic neoplastic cells, containing abundant eosinophilic cytoplasm and a round to ovoid, occasionally bizarre nucleus, were arranged interwoven. The neoplasm had metastasized to the right axillary lymph node. The neoplastic cells were intensively positive for vimentin, desmin and myoglobin. Skeletal muscle type creatine phosphokinase-positive granules were detected in the cytoplasm. Ultrastructurally, various amounts of disorganized myofibrils with focal density resembling the Z-band were shown in the cytoplasm of the neoplastic cells. The neoplasia was diagnosed as rhabdomyosarcoma.     

Neuroendocrine mechanism mediating energetic regulation of gonadotropin release in female rats

Energy level is a critical factor controlling gonadal activity at various phases of reproduction. A female rat model has revealed that fasting‐induced luteinizing hormone (LH) suppression is mediated by a specific neural pathway, such as noradrenergic neurons originating in the A2 region and projecting to the hypothalamic paraventricular nucleus and corticotropin‐releasing hormone neurons. The pathway is shared with that mediating glucoprivic suppression of LH pulses. Among the peripheral signals altered by energy deficiency, glucose could be a signal molecule conveying the peripheral information to the brain to regulate feeding and gonadotropin‐releasing hormone/LH release through the noradrenergic pathway during undernutrition. The brain detects the energy availability to control feeding and reproductive function at various phases of an animal’s life. It is most likely that the central glucose‐sensing mechanism could be similar to the pancreatic one, involving a glucokinase‐mediated process to detect glucose availability. Further studies are needed to elucidate the mechanism integrating the energy signals.     

The genetic legacy of Paleolithic Homo sapiens sapiens in extant Europeans: a Y chromosome perspective

A genetic perspective of human history in Europe was derived from 22 binary markers of the nonrecombining Y chromosome (NRY). Ten lineages account for >95% of the 1007 European Y chromosomes studied. Geographic distribution and age estimates of alleles are compatible with two Paleolithic and one Neolithic migratory episode that have contributed to the modern European gene pool. A significant correlation between the NRY haplotype data and principal components based on 95 protein markers was observed, indicating the effectiveness of NRY binary polymorphisms in the characterization of human population composition and history.     

Effects of organic carbon and clay contents on structure-related properties of arable soils with high clay content

Understanding of factors governing soil structural features is necessary for managing key processes affecting crop productivity and environmental impacts of agriculture, for example, soil water balance, aeration, and root penetration. Organic matter is known to act as a major binding agent in soil aggregation and thus constitutes a central pillar in soil structure formation. However, knowledge of the structural role of organic matter or carbon (OC) in soils highly rich in clay-sized particles (<0.002 mm) is limited. In this study, the effects of clay and OC contents on aggregate stability, water holding capacity, near-saturated hydraulic conductivity, total porosity, and pore size distribution were assessed in cultivated fields with high clay content located in private crop production farms in southern Finland. Significant positive correlations were found between OC content and proportion of water stable aggregates and specific pore sizes from the range of 30 μm up to 1 mm diameter determined by image analysis. Porosities on a smaller size range derived from water retention measurements likewise showed a positive correlation with OC in <0.2 μm sizes. On the range of 0.2–1 μm, a negative relationship was observed, which induced a negative effect of OC on soil plant available water reserves. In line with the positive correlation between OC and larger soil pores, free water, representing the amount of water that can be drained by gravity, exhibited a positive relationship with OC suggesting that OC content can enhance aeration of soils with high clay content. Compared to OC, clay content tended to have an adverse effect on soil structural properties. Clay correlated negatively with pores larger than 30 μm, free water content, and extrapolated field saturated hydraulic conductivity. Further, our imaging results showed how saturated hydraulic conductivity was controlled by pore morphology, and there was a power law relationship between the conductivity and critical pore diameter. $K\propto d_c^2$ in agreement with the percolation theory. Overall, the structural impacts and hydrological implications of OC and clay in heavy clay soils vary by pore size ranges and their emergent practical impacts are thus not straightforward.