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Data on collisions of birds with high-voltage electric power lines are scarce and are often gathered without protocols for the correction of carcass disappearance. There is actually growing awareness that it is important to accomplish carcass removal trials in order to develop correction factors for producing adjusted estimates of mortality due to collisions. In this study, we provided for the first time raw counts and estimates of bird collisions across seven Italian areas that largely differ in their habitats. We also carried out carcass removal trials to compute the rate of carcass disappearance and produce better estimates of collision events and of optimal time intervals of carcass searches. Results of 1-year monitoring showed a general low frequency of birds collided with the power lines. Carcass removal trials showed effects of carcass size and season on the carcass disappearance, which varied largely among the study areas. In four areas, both small and large carcasses had more than 50% probability to be removed within 3-5 days from their distribution. Given the high variation among study areas, we suggest that estimates of carcass persistence and optimal time intervals should be conducted concurrently for each new study site. [ABSTRACT FROM AUTHOR]

Changes in local weather conditions may affect reproduction in birds. In this study, we evaluated how changes in both local weather and winter North Atlantic Oscillation (the NAO, an index of non-local climatic conditions) could explain variation in selected reproductive traits (laying date, clutch size, hatching and fledging success) in Mediterranean kestrels Falco tinnunculus over 10 years. Kestrels (1) delayed the laying date in rainier springs; (2) laid smaller clutches after warmer and rainier winters, independently from the laying date; (3) had higher hatching success after warmer and dry winters and in warmer and rainier springs; (4) had higher fledging success in warmer and rainier springs. Thus, changes in the weather and the winter NAO index affected reproductive decisions and reproductive success. Predicting the long-term effects of global warming on the viability of Mediterranean populations of kestrels and other birds of prey is difficult. Whether the reproduction of birds of prey will be positively or negatively affected by global warming will depend on the relative importance of changes in temperature and rainfall. [ABSTRACT FROM AUTHOR]

Abstract. Dell'Omo G, Giorgi D, Di Bello V, Mariani M, Pedrinelli R (Università di Pisa, Pisa, Italy). Blood pressure independent association of microalbuminuria and left ventricular hypertrophy in hypertensive men. J Intern Med 2003; 254: –. Background. Rather unique amongst the prognostic predictors, microalbuminuria (MA, albuminuria: 15–200 μg min-1 ) is associated with several cardiovascular risk factors including left ventricular hypertrophy (LVH). The relationship, usually assumed to reflect an increased blood pressure (BP) load on the heart and the kidney, may, however, represent more than a haemodynamic correlate. Methods. To evaluate this possibility, we related MA to left ventricular mass index (LVMI) and other functional and structural echocardiographic parameters, office and 24-h BP, weight, lipids and smoking status in 330 never treated nondiabetic hypertensive men. Results. The risk of MA increased linearly by ascending quartiles of LVMI and was 2.3-fold higher in the presence of LVH after adjustment for age, left atrial size, mean fractional shortening. Systolic BP, either office or 24 h, and smoking status were the only additional independent predictors in multivariate logistic regression models. The BP-adjusted risk of MA was about twofold higher in patients with LVH, either concentric or eccentric, and neutral in those with concentric remodelling compared with normal geometry. Conclusions. The association between elevated LVMI and MA independent of several other potential confounders, systolic BP in particular, is consistent with the existence of cardiac albuminuric factors, possibly of hormonal nature, which are to be identified more precisely. The extent to which LVH explains the predictive power of MA for morbid events independent of the BP load remains unknown. [ABSTRACT FROM AUTHOR]

Continuous exposure to ozone (O3, 1.2 ppm) in adult CD-1 male mice for 20 consecutive days markedly influenced a number of items of aggressive behavior induced by 59 days of individual housing. The behavior of mice was videotaped on days 1, 3, and 5 of five consecutive daily encounters (10 min each; isolation days 55, 57, and 59). Ozone exposure caused an abatement of aggressive behavior and enhanced fear-associated displays shown by a significant decrease in the frequency of attacking and digging and an increase in freezing. Moreover, O3 induced a decrease or time spent in attacking and exploration/activity. Nonexposed animals exhibited a day-dependent increase in self-grooming frequency which was not observed in O3 mice; by contrast, freezing was higher m O3 mice on day 5 of the lest. Data suggest that O3 exposure produces a remarkable reduction of mouse aggression, indirectly confirming previous findings on physical and neurobehavioral effects of O3. [ABSTRACT FROM AUTHOR]

Earthworms Esinia spp. were kept for a 48-h period in artificial soil contaminated with a sublethal dose of dimethoate, an organophosphate pesticide. Different groups of common shrews, Sorex araneus, were fed earthworms that had been exposed to contaminated soil either 1, 5,or 10 d previously. Cholinesterase (ChE) activity was measured in worms and in the shrews before and after they were fed contaminated worms. After exposure to dimethoate-treated soil, ChE activity in worms was inhibited by 90%. Recovery was slow, and ChE activity was still markedly inhibited (35% of the control level) 40 d after exposure. Whole blood ChE activity in shrews was significantly depressed (64% of preexposure levels) when animals were fed worms that had been exposed to dimethoate-treated soil on the previous day. There was no such significant inhibition in shrews fed worms that had been exposed to contaminated soil either 5 or 10 d previously. [ABSTRACT FROM AUTHOR]

The behavioral and physiological effects of exposure to dimethoate, an organophosphate (OP) pesticide, were examined in common shrews, Sorex araneus, under laboratory conditions. Shrews were given either saline or an acute sublethal dose (50 mg/kg intraperitoneal) of dimethoate, and a time course of behavior was recorded in five 10-min open field tests spaced over a 12-h period. Parallel measurements of brain acetylcholinesterase (AChE) activity were carried out to monitor the onset of brain AChE inhibition and its subsequent recovery. Dimethoate produced a significant depression of locomotor activity for approx.6 h. Rearing, exploring, and sniffing activities were also significantly inhibited. The observed behavioral effects coincided with the maximal inhibition of AChE and disappeared before the brain AChE level had recovered. Statistically significant correlations were observed between the reduced frequencies of exploring, rearing, and crossings (a measure of locomotor activity) and the severity of inhibition of brain AChE activity, suggesting that brain AChE activity, the biomaker of exposure, could be used as a predictor of the severity of OP-induced effects on behavior. [ABSTRACT FROM AUTHOR]

It is hypothesized that a central role of the vertebrate hippocampal formation (HF) in behavior is the learning and operation of a map-like representation of familiar landmarks and landscape features. One critical property of a map is that it should enable an individual to re-orient towards a goal location following a navigational error. To test this prediction on a spatial scale consistent with their naturally occurring behavior, control and HF-lesioned homing pigeons were trained from two locations and then subsequently released, while carrying portable GPS-tracking devices, following a phase-shift treatment. Analyses revealed that the HF-lesioned pigeons were less successful than control pigeons in re-orienting homewards following the phase-shift-induced error in their initial orientation. Furthermore, the observation that HF-lesioned pigeons were found to routinely ignore a land-sea landscape boundary when returning home from one of the release sites suggests that coarse landscape features may be an underappreciated source of navigational information for homing pigeons. The data demonstrate that, on a scale of tens of kilometers, homing pigeons are able to learn a hippocampal-dependent, map-like representation of familiar landmarks/landscape features that can support corrective re-orientation following a navigational error.

Mice inoculated with transmissible spongiform encephalopathies (TSE) show behavioural abnormalities well before the appearance of clinical signs. TSE strains are obtained by serial re-infection of infectious brain homogenates in laboratory rodents. They are characterized by strain-typical brain lesion profiles, which implies that they might be differentiated behaviourally as well. Seventy female C57BL/6 mice were tested, 14 per group. Controls received no or sham inocula, two other groups received scrapie strains adapted to mice (139A, ME7) and one group a mouse-adapted BSE strain (301C). From week 7 until the end of the incubation period, 8 mice per group were subjected once every 2 weeks to open-field and hot-plate tests. Assessment of clinical signs, and measuring of body weight, food and water consumption were carried out weekly on the remaining animals kept in single cages. In addition, locomotor activity was recorded continuously in these mice by means of infrared detectors. Monitoring of circadian activity revealed early significant TSE strain differences, most pronounced during the nocturnal active phase. Behavioural changes in open-field tests also occurred before the appearance of clinical signs, and differences in rearing, wall rearing and sniffing were strain-specific, however, such differences varied according to the period of testing. Hind paw lick latencies increased equally in all groups after week 19, jump latencies also increased in the two scrapie groups but not in the BSE group. It was at this time that clinical signs first appeared consisting of ataxia, lack of balance, motor dyscoordination, and lordosis. These data imply that automated assessment of circadian activity in mice is a powerful and economical tool for early behavioural typing of TSE strains.

It is not known if diastolic abnormalities are independent of systolic dysfunction in arterial hypertension. We studied three groups of 10 male subjects of comparable mean age (31.6 +/- 3.5 years), weight, and height: Athletes (A) (cyclists), essential hypertensive patients (H), and controls (C). Ultrasonic myocardial integrated backscatter signals (IBS) of the septum and the posterior wall were analyzed, while the systo-diastolic variation of the backscatter was considered as a cyclic variation index (CVI(ibs)). Myocardial velocities across the left ventricular major axis were sampled at septum and lateral wall levels by pulsed-wave Doppler tissue imaging (DTI). CVI(ibs) at the septum and the posterior wall were significantly lower in the hypertensive group in comparison with athletes and controls, who were comparable. Early diastolic myocardial velocity (E(m)) of the lateral wall and of the septum were significantly lower in hypertensives, while the late diastolic myocardial velocity (A(m)) was significantly higher in hypertensives in comparison with athletes. The E(m)/A(m) at the septum level was significantly lower in hypertensives in comparison with athletes and controls. Significant correlations were found between CVI and DTI parameters: CVI(ibs) and E(m)/A(m) septum (r = 0.50, P < 0.002). Furthermore, significant correlations were found between mean arterial pressure (MAP) and E(m)/A(m) septum (r = - 0.65, P < 0.001). Ultrasonic tissue characterization with the intrinsic contractility study and the evaluation of the regional diastolic function should, therefore, represent a new integrated diagnostic modality for the evaluation of left ventricular hypertrophied intramyocardial function. This study demonstrated that diastolic abnormalities of left ventricular function, in arterial hypertension, are related and progress with systolic intrinsic dysfunction.