Intensive management fails to promote recruitment in the last large population of Juniperus communis (L.) in Flanders (Belgium)

In this study, the effectiveness of management measures aimed at promoting recruitment in the last large Flemish juniper population at Heiderbos is evaluated. We resurveyed demographic plots 23 years after their establishment in 1980 and linked the population changes with detailed records of the intensive management during the same period. Between 1980 and 2003 the population size has decreased by 36% and has changed from a relatively immature to a mature population with very few young individuals. Based on a simple model that simulated height growth between 1980 and 2003, the recruitment and mortality rates were estimated to be 5 and 24 ha⁻¹ yr⁻¹, respectively. Intensive management has thus not been able to promote recruitment and the population might go extinct within 40 years if these rates remain unchanged. Furthermore, some measures, notably the working of the soil, have increased mortality of established junipers. The reasons for the limited recruitment are not entirely clear yet, but it may be due to a combination of the limited availability of bare ground for germination and the extremely low viability of juniper seeds. The latter fact may be a common characteristic of many threatened juniper populations in northwestern Europe.     

The effect of mass-flowering orchards and semi-natural habitat on bumblebee colony performance

Landscape Ecology - Bumblebees are important pollinators for agricultural crops and wild plants. However, agricultural intensification and loss of semi-natural habitat may have adverse effects on...     

Quantification of left ventricular longitudinal strain, strain rate, velocity, and displacement in healthy horses by 2-dimensional speckle tracking

Background: The quantification of equine left ventricular (LV) function is generally limited to short‐axis M‐mode measurements. However, LV deformation is 3‐dimensional (3D) and consists of longitudinal shortening, circumferential shortening, and radial thickening. In human medicine, longitudinal motion is the best marker of subtle myocardial dysfunction. Objectives: To evaluate the feasibility and reliability of 2‐dimensional speckle tracking (2DST) for quantifying equine LV longitudinal function. Animals: Ten healthy untrained trotter horses; 9.6 ± 4.4 years; 509 ± 58 kg. Methods: Prospective study. Repeated echocardiographic examinations were performed by 2 observers from a modified 4‐chamber view. Global, segmental, and averaged peak values and timing of longitudinal strain (SL), strain rate (SrL), velocity (VL), and displacement (DL) were measured in 4 LV wall segments. The inter‐ and intraobserver within‐ and between‐day variability was assessed by calculating the coefficients of variation for repeated measurements. Results: 2DST analysis was feasible in each exam. The variability of peak systolic values and peak timing was low to moderate, whereas peak diastolic values showed a higher variability. Significant segmental differences were demonstrated. DL and VL presented a prominent base‐to‐midwall gradient. SL and SrL values were similar in all segments except the basal septal segment, which showed a significantly lower peak SL occurring about 60 ms later compared with the other segments. Conclusions and Clinical Importance: 2DST is a reliable technique for measuring systolic LV longitudinal motion in healthy horses. This study provides preliminary reference values, which can be used when evaluating the technique in a clinical setting.     

Small forest patches as pollinator habitat: oases in an agricultural desert?

Landscape Ecology - Small forest fragments are often the most abundant type of semi-natural habitat in intensive agricultural landscapes. Wild pollinators can use these forest patches as nesting or...     

Role of IFN-α during the acute stage of a swine influenza virus infection

Cytokines, especially interferon-alpha (IFN-α) are important in controlling influenza virus infections. To investigate the role of IFN-α in influenza, the swine IFN-α neutralizing monoclonal antibody (Ab) K9 was applied in a swine model of influenza A virus infection. First, the optimal dose and route for administration of the IFN-α neutralizing Abs was determined. Based on those results, the effect of the Abs on a swine influenza virus infection was investigated. Pigs were inoculated intratracheally with 10^6.0 mean egg infectious dose (EID₅₀) A/Swine/Belgium/1/98 (H1N1) virus. At the time of challenge and 18 h later, they were injected intratracheally and intraperitoneally with a high dose of IFN-α neutralizing Abs or control Abs. The animals were euthanized at 0, 24, 30, 48 and 72 h after inoculation. At 24 and 30 h, IFN-α levels in broncho-alveolar lavage fluid of K9 recipient animals were strongly suppressed, and this coincided with reduced IL-6 and IL-12 levels. TNF-α and IL-1 levels were unaffected compared to those in the control Ab treated group. Importantly, the onset and peak of clinical symptoms in IFN-α neutralizing Abs treated animals were delayed by 24 h, simultaneously with the suppression of IFN-α, but there was no obvious effect on virus replication and lung pathology. These results suggest an important role for IFN-α in IL-6 and IL-12 induction and a role of all three cytokines in the symptoms of swine influenza.     

Cross-sectional survey of owner knowledge and husbandry practices, tack and health issues affecting working horses in Lesotho

Reasons for performing study: To establish baseline parameters of equine health, owner knowledge and husbandry practices and tack against which benefits to local horses arising from an equine charity's training programme in Lesotho could be measured. Objectives: To describe and investigate associations between owner knowledge and equine husbandry practices, horse health and tack‐related parameters prior to the start of the training programme. Methods: A cross‐sectional survey was undertaken in the catchment area of students attending the first training course. Owners from randomly selected villages were interviewed about horse care using a standardised, structured questionnaire, administered face to face in local language. Horses were clinically examined and tack assessed according to standardised protocols. Results: Clinical examinations were performed on 312 horses and 287 owners were interviewed. Owners had variable knowledge of equine husbandry and limited understanding of appropriate primary and preventive healthcare. Equine health problems identified included ecto‐ and endoparasite infestation, mouth lesions, overgrown and unbalanced feet and tack‐associated wounds. The majority of tack was in poor condition, dirty and ill‐fitting. With the exception of below‐average body condition score, no associations were found between key adverse horse‐related clinical findings and owners reporting their horse as being ‘unhealthy’. Conclusions: Working horses in Lesotho have a range of physical problems, many of which could be ameliorated through targeted owner education. With limited access to veterinary advice and scarce resources, improved availability of affordable local equine trade skills is key to improving equine health. Potential relevance: Findings could be used to inform and direct training programmes to maximise benefits to equine health and to serve as a baseline against which to monitor effects of educational and other interventions.