Artificial Nesting Hills Promote Wild Bees in Agricultural Landscapes

The availability of nesting resources influences the persistence and survival of bee communities. Although a positive effect of artificial nesting structures has frequently been shown for aboveground cavity-nesting wild bees, studies on below ground-nesting bees are rare. Artificial nesting hills designed to provide nesting habitats for ground-nesting bees were therefore established within the BienABest project in 20 regions across Germany. Wild bee communities were monitored for two consecutive years, accompanied by recordings of landscape and abiotic nest site variables. Bee activity and species richness increased from the first to the second year after establishment; this was particularly pronounced in landscapes with a low cover of semi-natural habitat. The nesting hills were successively colonized, indicating that they should exist for many years, thereby promoting a species-rich bee community. We recommend the construction of nesting hills on sun-exposed sites with a high thermal gain of the substrate because the bees prefer south-facing sites with high soil temperatures. Although the soil composition of the nesting hills plays a minor role, we suggest using local soil to match the needs of the local bee community. We conclude that artificial nesting structures for ground-nesting bees act as a valuable nesting resource for various bee species, particularly in highly degraded landscapes. We offer a construction and maintenance guide for the successful establishment of nesting hills for bee conservation.

Replacement of ureteric segments by intubated neo-ureterotomies (modified Davis technique) using autologous bladder and omentum in dogs

In 14 dogs, using a modified Davis technique, excised segments of ureters were replaced by free, partial-thickness bladder grafts vascularised by omentum. Eight of the 14 dogs had satisfactory radiological appearances of the operated upper tracts at 12 months, and 9 of the 14 were unobstructed urodynamically at this time. Graft segments did not appear to contract. Urothelial and smooth muscle regeneration was observed.

Pimozide attenuates lever pressing for water reinforcement in rats

Rats were trained to lever-press for water on a schedule of continuous reinforcement, then tested every fourth session on five occasions either under conditions of non-reinforcement or following injections of the dopamine receptor blocker pimozide (0.5 or 1.0 mg/kg) or the injection vehicle. The low dose of pimozide did not significantly attenuate responding until the fifth session. The high dose attenuated responding on all occasions, with residual responding decreasing progressively across repeated drug sessions. Responding in the pimozide conditions was never less than that of the non-reinforced control group. Responding in each condition was strongest in the early minutes of a session. After five sessions, rats were switched from the pimozide condition to the non-reinforced condition (or vice-versa) for one additional test day. Decreased responding continued for rats transferred from non-reinforcement to pimozide though not for rats transferred from pimozide to non-reinforcement. These data suggest a role for brain dopamine in behavior; they reflect the same patterns as have been seen with food reinforcement and with several centrally-acting reinforcers.