Do olfactory behaviour and marking responses of Konik polski stallions to faeces from conspecifics of either sex differ?

The aim of the study was to assess whether adult stallions differentiate their olfactory and marking behaviour towards the excreta of their potential male rivals and mares. Four Konik polski stallions were individually exposed simultaneously to their own and each others' faeces as well as faeces of mares in oestrus vs. dioestrus. Five series of 30min observation sessions were conducted in a round pen each on two consecutive days from March to July, totaling in 5h observation per stallion. Stallions sniffed and displayed flehmen reaction towards mares' faeces significantly longer (P<0.01) than towards stallions' faeces. No significant differences were found in marking by defecations upon stallions' vs. mares' faeces. The stallions urinated exclusively on mares' faeces. Sniffing, flehmen, defecations and urinations performed towards faeces of mares in oestrus vs. dioestrus did not differ significantly. The results showed that stallions differentiate their olfactory behaviour towards excreta of conspecifics of different sex but perhaps not towards faeces of females in different reproductive status. This for the first time establishes that stallions exhibit different marking behaviour upon stallions' vs. mares' faeces. It is hypothesized that marking of other stallions' faeces by defecation may advertise presence of the stallion, whereas marking of mares' faeces by urination may serve to mask the presence of a mare to prevent potential rivals from locating the mare in an area where mares' faeces are found.

Echocardiographic Correlates of Abnormal Liver Tests in Patients with Exacerbation of Chronic Heart Failure.

BACKGROUND: Elevated total bilirubin (TB) and transaminases are frequently reported in patients with heart failure and are related to their worse prognosis. On the basis of hemodynamic data from previous studies, the investigators hypothesized that elevated bilirubin and transaminases are associated with different patterns of cardiac remodeling and dysfunction in patients with heart failure (i.e., elevated bilirubin with predominantly right-heart dysfunction and elevated transaminases with predominantly left-heart dysfunction). Therefore, the aim of this study was to evaluate prospectively echocardiographic correlates of elevated TB and transaminases on admission in patients with exacerbation of chronic heart failure. METHODS: The following echocardiographic parameters were prospectively analyzed in 150 patients (mean age, 75 years; 59% men): right ventricular end-diastolic diameter, right atrial area, tricuspid regurgitation, right ventricular systolic pressure, tricuspid annular plane systolic excursion, tricuspid lateral annulus systolic velocity, estimated right atrial pressure, portal vein pulsatility index (PVPI), left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction, and cardiac index. RESULTS: Elevated TB was found in 61 patients (41%) and elevated transaminases in 46 patients (31%). In univariate logistic regression analysis, right ventricular end-diastolic diameter, right atrial area, tricuspid regurgitation, estimated right atrial pressure, tricuspid annular plane systolic excursion, tricuspid lateral annulus systolic velocity, PVPI, left ventricular ejection fraction, and cardiac index were significant predictors of elevated TB (P < .05 for all). LVEDD indexed to body surface area, right ventricular end-diastolic diameter, and systolic blood pressure on admission were significant predictors of elevated transaminases (P < .05 for all). In a multivariate regression model, only PVPI remained a significant predictor of elevated TB and LVEDD indexed to body surface area of elevated transaminases. Sensitivity, specificity, and positive and negative predictive values of PVPI > 0.5 in the prediction of elevated TB were 81%, 87%, 82%, and 87%, respectively. CONCLUSION: Several echocardiographic indices of right-heart dysfunction and low cardiac index are related to elevated TB, with an increased PVPI having the best predictive value. A weak statistically significant association was found between elevated transaminase levels and left ventricular end-diastolic diameter indexed to body surface area.

Efficacy of drug detection by fully-trained police dogs varies by breed, training level, type of drug and search environment.

Some recent publications claim that the effectiveness of police canine drug detection is uncertain and likely minimal, and that the deterrent effect of dogs on drug users is low. It is also claimed that more scientific evidence is needed to demonstrate to what extent dogs actually detect drugs. The aim of this research was to assess experimentally, but in actual training and testing environments used by the Polish police, how effective dogs trained by the police were at illicit substance detection depending on factors such as type of drug, dog breed, dog experience with the searching site, and drug odor residuals. 68 Labrador retrievers, 61 German shepherds, 25 Terriers and 10 English Cocker Spaniels, of both sexes in each breed, were used. Altogether 1219 experimental searching tests were conducted. On average, hidden drug samples were indicated by dogs after 64s searching time, with 87.7% indications being correct and 5.3% being false. In 7.0% of trials dogs failed to find the drug sample within 10min. The ranking of drugs from the easiest to the most difficult to detect was: marijuana, hashish, amphetamine, cocaine, heroin. German shepherds were superior to other breeds in giving correct indications while Terriers showed relatively poor detection performance. Dogs were equally efficient at searching in well-known vs. unknown rooms with strange (i.e., non-target novelty) odors (83.2% correct indications), but they were less accurate when searching outside or inside cars (63.5% and 57.9% correct indications respectively). During police examination trials the dogs made more false alerts, fewer correct indications and searching time was longer compared to the final stage of the training. The drug odor may persist at a site for at least 48h. Our experiments do not confirm the recent reports, based on drug users' opinions, of low drug detection efficiency. Usefulness of drug detection dogs has been demonstrated here, even if their effectiveness may not be 100%, but different factors have to be taken into consideration to assure maximum effectiveness.

Do trained dogs discriminate individual body odors of women better than those of men?

Scent identification lineups using dogs are a potentially valuable forensic tool, but have been dismissed by some critics because of cases where a false identification was shown to have occurred. It is not known, however, why dogs appear to make more false indications to the odors of some persons than of others. In this study, human genders were compared as to the degree their individual odors are distinguishable or "attractive" to dogs. Six dogs were trained to smell an individual's hand odor sample and then find the matching hand odor sample in a lineup of five odors. Using one-gender lineups and two-gender lineups with different gender ratios, it was found that dogs trained for the study identified individual women's hand odors more accurately than those of men. It is hypothesized that this is either because of differences in chemical compounds making discrimination of women's odors easier, or because of greater "odor attractiveness" of women's scents to dogs.