The evolutionary demography of ecological change: linking trait variation and population growth

Population dynamics and evolutionary change are linked by the fundamental biological processes of birth and death. This means that population growth may correlate with the strength of selection, whereas evolutionary change can leave an ecological signature. We decompose population growth in an age-structured population into contributions from variation in a quantitative trait. We report that the distribution of body sizes within a population of Soay sheep can markedly influence population dynamics, accounting for up to one-fifth of observed population growth. Our results suggest that there is substantial opportunity for evolutionary dynamics to leave an ecological signature and visa versa.     

Hyperprogesteronemia associated with Sertoli cell tumor and alopecia in a dog

Hyperprogesteronemia was found in a dog with alopecia and Sertoli cell tumor. Alopecia began in the lumber areas; the entire coat was dull and dry, and epilated easily. The only laboratory abnormalities were high serum progesterone concentration and incomplete suppression of cortisol after low-dose dexamethasone administration. The hair regrew after castration, and the progesterone concentration decreased toward normal.     

A national serological survey to verify Australia's freedom from porcine reproductive and respiratory syndrome

Objective To provide serological data to support Australia's claim of freedom from porcine reproductive and respiratory syndrome.
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus.     

Evaluation of an Immunochromatographic Test to the Diagnosis of Canine Brucellosis Caused by Brucella canis

This study evaluated the performance of an immunochromatographic test (ICT) for the diagnosis of canine brucellosis caused by Brucella canis, comparing its results with that of the rapid slide agglutination test with and without the use of 2‐mercaptoethanol and the agar gel immunodiffusion test (AGID). The microbiological culture, PCR and clinical examination were used as reference. According to the results obtained in clinical examination, blood culture, culture of semen and vaginal swab and PCR in blood, semen and vaginal swab, a total of 102 dogs were divided into three groups: B. canis‐infected dogs (Group 1), B. canis‐non‐infected dogs (Group 2) and dogs with suspected brucellosis (Group 3). The diagnostic sensitivity of RSAT, 2ME‐RSAT, AGID and ICT in Group 1 was, respectively, 75%, 37.5%, 27.8% and 89.58%. The diagnostic specificity of RSAT, 2ME‐RSAT, AGID and ICT in Group 2 was, respectively, 91%, 100%, 100%, and 100%. In dogs with suspected brucellosis, 9.67% were RSAT positive, none was positive by 2ME‐RSAT, 3.22% were AGID positive and 6.45% were ICT positive. The main drawback concerning canine brucellosis diagnosis is the lack of a highly sensitive serological assay to be used as a screening test to the rapid identification of infected animals. The ICT showed a high diagnostic specificity and a diagnostic sensitivity value greater than that observed in the RSAT, 2ME‐RSAT and AGID. However, 10.41% of infected dogs had negative results by ICT. These dogs were positive by microbiological culture and/or PCR, indicating active infection and consequently a higher potential of spreading Brucella. Although rapid and simple to perform, the ICT lacked sensitivity to be used as a screening test.     

Intelligent geographic information systems and integrated pest management

Research in integrated pest management (IPM) has resulted in the development of an immense knowledge base that requires computer-aided methodologies for integration, interpretation and delivery. Examined in this paper are four issues of concern to decision-making and problem-solving for IPM. First, the IPM enterprise is examined in the context of contemporary landscape ecology principles. The functional unit for IPM is defined to be the ecotope (a term intended to embody concepts of ecosystem functionality in the context of topographical dimension). A landscape consists of a mosaic of interacting ecotopes. The scope of IPM extends beyond forest and farm management and includes issues associated with environmental management. Second, the utility of geographic information systems (GISs) for IPM is considered. GISs add a new dimension to IPM in that they provide a mechanism for dealing with site-specific and spatially referenced data. The addition of methodologies from artificial intelligence expert systems, in particular, permits integration of qualitative knowledge of human experts with quantitative information that is the product of research. The resulting software system is termed an intelligent geographic information system, IGIS. This system allows for automated interpretation within and among landscape data themes. The product is an interpretative map or a tabular report. Third, utility of the IGIS approach is illustrated by an example involving habitat delineation for an endangered species, the Houston toad. In this example a simple rulebase is developed that defines habitat locations that would be suitable for the toad. Fourth, a concept and method for integrating the different types of knowledge available for IPM (published research results and reports, spatial and tabular databases, simulation models, and observations and experiences of human experts) is described. This software system, the knowledge system environment, retains the unique features of an IGIS but is more useful in that it employs the full measure of knowledge available from IPM. With new technology from computer science and concepts from information engineering, it has been possible to formulate a new conceptual model of IPM that incorporates both the information systems needed as well as the activities required for implementation of IPM.     

Use of transesophageal echocardiography for visualization of the patent ductus arteriosus during transcatheter coil embolization

Transesophageal echocardiography (TEE) enhances our ability to see the patent ductus arteriosus in the dog. The improved visualization may potentially improve our ability to perform transcatheter coil embolization in patients that are more likely to have a successful outcome. This report uses still and video images to detail the specifics of coil embolization as performed with the assistance of TEE and compares the images with those of angiography, surgery and postmortem examination.