In broiler breeder flocks in one broiler integration in Hungary, a new syndrome appeared in January 2005 with initially four successive post-peak flocks experiencing significant decreases in egg production. Clinically birds became depressed and there was a small increase in the mortality rate. Postmortem examinations revealed enlarged livers in up to 19% of birds dying, and enlarged spleens in some. Also observed were birds with either clotted blood or serosanguineous fluid in the abdomen and subcapsular haemorrhages of the liver. Histopathology and polymerase chain reaction excluded tumours and the presence of common tumour-associated viruses. Chronic bacterial infections (especially causing hepatitis, peritonitis and airsacculitis) were common but many enlarged livers had no obvious bacterial involvement. After a 9-month period during which a majority of flocks became affected, no newly affected flocks occurred. Investigations showed that all tested affected flocks were seropositive in the big liver and spleen (BLS) Agar Gel Immuno Diffusion (AGID) test. Subsequent flocks without post-peak egg-production drops were shown to be seronegative in the BLS AGID test, as were all the parent flocks contributing to the affected flocks. Liver samples and cloacal swabs were positive by polymerase chain reaction (aHEV helicase target), and calicivirus-like particles were demonstrated in bile samples from affected birds. These observations are similar to hepatitis-splenomegaly syndrome as described in North America and BLS syndrome as described in Australia. Histopathological features were a non-specific chronic hepatitis similar to those described in BLS and hepatitis-splenomegaly syndrome. Immunohistochemistry using a BLS-specific monoclonal antibody confirmed the presence of avian hepatitis E virus antigen in livers and spleen.
Dolphins use their biosonar to discriminate objects with different features through the returning echoes. Cross-modal matching experiments were conducted with a resident bottlenose dolphin (Tursiops aduncus). Four types of objects composed of different materials (water-filled PVC pipes, air-filled PVC pipes, foam ball arrays, and PVC pipes wrapped in closed-cell foam) were used in the experiments, respectively. The size and position of the objects remained the same in each case. The data collected in the experiment showed that the dolphin’s matching accuracy was significantly different across the cases. To gain insight into the underlying mechanism in the experiments, we used finite element methods to construct two-dimensional target detection models of an echolocating dolphin in the vertical plane, based on computed tomography scan data. The acoustic processes of the click’s interaction with the objects and the surrounding media in the four cases were simulated and compared. The simulation results provide some possible explanations for why the dolphin performed differently when discriminating the objects that only differed in material composition in the previous matching experiments.
Cognitive enrichment aims to provide animals with opportunities to use their cognitive skills and to promote behaviors associated with positive wellbeing. Cooperation in mammals has been recorded during various behavioral contexts such as hunting, mating, playing, and parental care. Coordinated activity, often with some level of problem-solving action included, is required during cooperation. To investigate dolphins' ability for collaborative problem-solving, an enrichment device was introduced to two adult male Indo-Pacific bottlenose dolphins (Tursiops aduncus). The device contained fish and ice and was designed to be opened by simultaneously pulling on both ends. After repeated presentation, it became apparent that only one dolphin had active interest in the device. To facilitate opportunities for problem-solving by this individual, an alternative collaborator, a human partner, was provided. Still, both dolphins had access to the device throughout the entire experiment. After the first opening, the same dolphin was highly successful in collaborating with the human in both joined (93%) and delayed (100%) partner conditions. The device provided a novel opportunity for the dolphin to use his cognitive skills. Even though only one dolphin participated actively, both dolphins showed varying degrees of interest to the device throughout the study. Both dolphins spent an average of 48% and 16% of their time, respectively, with the device, which resulted in a significant decrease in their other two most frequently observed behaviors: swimming and poolside observation. As a novel cognitive challenge, the device may be considered as a type of cognitive enrichment. K E Y W O R D Sanimal welfare, cognitive challenge, dolphin, problem-solving
Hematologic and plasma biochemistry parameters of the white stork (Ciconia ciconia) were studied. Blood samples were taken from a total of 80 adult white storks kept in captivity in Hungarian zoos and bird repatriation stations, between 2002 and 2006. Hematologic (packed cell volume, 46.3% +/- 5.3%; hemoglobin concentration, 127.8 +/- 20.4 g/L; red blood cell counts, 2.28 +/- 0.35 10(12)/l/l; white blood cell counts, 21.6 +/- 4.2 10(9)/l/ l; heterophils, 61.0% +/- 9.8% [13.1 +/- 3.2 x 10(9)/L]; lymphocytes, 34.3% +/- 9.1% [7.4 +/- 2.5 x 10(9)/L]; monocytes, 3.44% +/- 2.3% [0.78 +/- 0.57 x 10(9)/L]; eosinophils 0.75% +/- 0.91% [0.16 +/- 0.21 x 10(9)/L]; basophils 0.38% +/- 0.56% [0.04 +/- 0.07 x 10(9)/L]) and plasma biochemistry values (aspartate aminotransferase, 267.5 +/- 145.8 U/L; L-gamma-glutamyltransferase, 47.6 +/- 49.3 U/L; lipase, 70.3 +/- 60.6 U/L; creatine kinase, 443.9 +/- 182.2 U/L; lactate dehydrogenase, 880.4 +/- 293.6 U/L; alkaline phosphatase, 177.5 +/- 116.6 U/L; amylase, 917.6 +/- 314.3 U/L; glutamate dehydrogenase, 7.3 +/- 4.0 U/L; total protein, 45.2 +/- 8.1 g/L; uric acid, 459.2 +/- 254.3 micromol/L; and bile acids, 46.3 +/- 20.5 micromol/L) were determined. The results obtained can be used as reference values, because there are no established values previously reported for adult white storks.
Rotational behaviour has been observed when dolphins track or detect targets, however, its role in echolocation is unknown. We used computed tomography (CT) data of one live and one recently deceased bottlenose dolphin together with measurements of the acoustic properties of head tissues to perform acoustic property reconstruction. The anatomical configuration and acoustic properties of the main forehead structures between the live and deceased dolphins were compared. Finite element analysis (FEA) was applied to simulate the generation and propagation of echolocation clicks, to compute their waveforms and spectra in both near- and far-fields, and to derive echolocation beam patterns. Modelling results from both the live and deceased dolphins were in good agreement with click recordings from other, live, echolocating individuals. FEA was also used to estimate the acoustic scene experienced by a dolphin rotating 180° about its longitudinal axis to detect fish in the far-field at elevation angles of -20° to 20°. The results suggest that the rotational behaviour provides a wider insonification area and a wider receiving area. Thus, it may provide compensation for the dolphin’s relatively narrow biosonar beam, asymmetries in sound reception, and constraints on the pointing direction that are limited by head movement. The results also have implications for examining the accuracy of FEA in acoustic simulations using recently deceased specimens.
Underwater imaging sonars are widely used for oceanic exploration but are bulky and expensive for some applications. The sonar system of dolphins, which uses sound pulses called clicks to investigate their environment, offers superior shape discrimination capability compared to human-derived imaging sonars of similar size and frequency. In order to gain better understanding of dolphin sonar imaging, we train a dolphin to acoustically interrogate certain objects and match them visually. We record the echoes the dolphin receives and are able to extract object shape information from these recordings. We find that infusing prior information into the processing, specifically the sparsity of the shapes, yields a clearer interpretation of the echoes than conventional signal processing. We subsequently develop a biomimetic sonar system that combines sparsity-aware signal processing with high-frequency broadband click signals similar to that of dolphins, emitted by an array of transmitters. Our findings offer insights and tools towards compact higher resolution sonar imaging technologies.
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