The complexity of the mast cell is becoming more prominent. From being the cell recognized just to contribute to allergic inflammation it is now also associated with wound healing, protection against tumor growth and in recognition and defense against a wide range of pathogens. The location of the mast cell in the barrier between the external and internal environment of the body enables the cell to quickly respond to invading bacteria, virus and parasites. Diarrhea due to Escherichia coli infection, listeriosis, toxoplasmosis, Newcastle disease and Bovine respiratory syncytial virus are examples of mast cell activating diseases that can affect animals in, as well as outside, the agricultural sector. Additionally, ticks and tick-borne diseases are of concern.

The Bovine respiratory syncytial virus (BRSV) causes bronchiolitis and interstitial pneumonia, predominantly in calves, and is a major cause of bovine respiratory disease worldwide. In humans, BRSV is paralleled by the closely related Human respiratory syncytial virus (HRSV), an important cause of respiratory disease, most severe in infants.The clinical signs and pathology during RSV infection is caused, not only by the direct effects of viral replication, but also by the response of the host immune system. The immunopathology of RSV has long obfuscated our understanding of the disease, and development of effective treatment and vaccines will be very difficult until greater knowledge is gained.One of the components of the immune system that has come into focus in RSV research the last few years, is the Toll-like receptor 4 (TLR4). The TLR4 receptor is well known as the receptor that binds lipopolysaccaride (LPS), and initiates the host response to bacterial infection. Recently, it has been shown that the fusion protein of RSV also interacts with, and up-regulates the expression of, the TLR4 receptor.

The Bovine respiratory syncytial virus (BRSV) causes bronchiolitis and interstitial pneumonia, predominantly in calves, and is a major cause of bovine respiratory disease worldwide. In humans, BRSV is paralleled by the closely related Human respiratory syncytial virus (HRSV), an important cause of respiratory disease, most severe in infants.The clinical signs and pathology during RSV infection is caused, not only by the direct effects of viral replication, but also by the response of the host immune system. The immunopathology of RSV has long obfuscated our understanding of the disease, and development of effective treatment and vaccines will be very difficult until greater knowledge is gained.One of the components of the immune system that has come into focus in RSV research the last few years, is the Toll-like receptor 4 (TLR4). The TLR4 receptor is well known as the receptor that binds lipopolysaccaride (LPS), and initiates the host response to bacterial infection. Recently, it has been shown that the fusion protein of RSV also interacts with, and up-regulates the expression of, the TLR4 receptor.

Bovine respiratory syncytial virus (BRSV) is a common cause of respiratory disease among young cattle. The virus causes severe losses; the herd mortality rate can sometimes be as high as 20 %. In this study the avidity (i.e the antigen binding force) of BRSV specific antibodies was measured to see if there was a difference between antibodies produced during an acute phase of infection and antibodies produced by earlier infected animals. A commercially available ELISA-testkit against BRSV-specific antibodies was used and an incubation step with 6M urea was added. The effect of the urea is that it breaks the weak bonds between antibodies and antigen while the stronger bonds remain intact. Four different groups of animals were included in this study; seven calves that were naturally infected, three acutely infected calves with known time of infection, five cows that were seropositive during several years and four experimentally infected calves that had been a part of a vaccine trial. The results of this study showed that antibodies produced during the acute phase of an infection had a low avidity and that the avidity increased with time after infection.

In Uganda, small scale pig production plays a major role for households to earn a living and to secure their access to meat. Piglet mortality due to diar-rhoea-related dieseases is high. In an attempt to understand the underlying causes for this high mortality this study aims to investigate the role of trans-missible gastroenteritis virus (TGEV) and is a part of a larger project con-ducted at Makerere university in Uganda. A complicating factor in this investigation is the porcine respiratory corona-virus (PRCV), a stabile mutant form of the TGE virus. The occurrence of this virus had shown to alter the impact of TGEV in e.g. Europe and North Amer-ica.

Nipahvirus is most likely spread from bats to other species and causes lethal encephalitis in humans and respiratory illness in pigs. Different species are affected with varying severity but it seems to have an unprecedented zoonotic capacity and the humans affected either die or receive permanent brain damage. Full recovery is possible but very uncommon. Pigs that live and are bread in the areas that these bats frequent are constantly in danger of contracting pneumonias and meningitis and they can spread the virus further on to the people who work with the pigs and process their carcasses. These workers could then infect other humans in their immediate surroundings, their families for instance.

West Nile Fever and West Nile Encephalitis are caused by the flavivirus West Nile Virus (WNV). West Nile Virus is now a dangerous threat for horses, birds and humans.

Bovine viral diarrhoea virus (BVDV) is the causative agent of a complex of disease syndromes in cattle with high economical and welfare impacts. BVDV occurs as two biotypes; cytopathic (BVDVcp) and noncytopathic (BVDVncp) determined by differential effects on cultured cells and can also be divided into two genotypes (BVDV1 and BVDV2) on the basis of genomic diversity. The interaction between BVDV and the host?s immune system is regarded a key aspect in the sequel of BVDV infection. Infection with BVDV normally causes an acute transient infection, with mild to subclinical signs, but occasionally results in severe and even fatal disease.

Scrapie is an infectious neurologic disease in sheep caused by prions, corresponding to transmissible spongiform encephalopathies (TSEs) in other species. The prion is presumably constituted of PrPSc, the misfolded form of the normal endogenous prion protein, PrPC, which is found in practically all cells in the body. PrPSc can induce a conformational change in PrPC and misfold it as an imprint of itself; this is how prions amplify and spread. The process of conformational change is poorly understood and there might exist intermediate forms between PrPC and PrPSc. Bioassay using mice has traditionally been the golden standard in prion studies but is limited by cost and time.

This paper shortly describes the coronavirus family, bovine corona viruses (BCV) properties and two diseases that BCV causes, winter dysentery and calf diarrhoea. The purpose of the study was to compare different diagnostic methods to detect BCV. Different methods are discussed, PCR, ELISA, immunofluorescense and virus isolation. Investigations were made in three different herds with winter dysentery; one dairy cattle farm with about 100 cows of different ages, one testing station for bulls with about 150 bulls and another small dairy cattle farm with 26 cows and 20 replacement heifers and calves. Faeces and nasal swabs were analysed with PCR and ELISA. The result shows that PCR seems to be a reliable method for detecting BCV but that the ELISA test can not be used as a reliable diagnostic method to analyse samples from animals with winter dysentery..

Luftvägssjukdomar är ett av de vanligaste hälsoproblemen hos kalvar och utgör en betydande kostnad för branschen. Luftvägssjukdomar är komplexa till sin natur och uppkommer endast då en kombination av faktorer som inkluderar djuret, miljön och infektiösa agens förekom-mer. Ofta är den primära patogenen ett virus och den påföljande lunginflammationen orsakas av bakterier. Ett bidragande virus, BVDV, har genom ett frivilligt kontrollprogram utrotats i Norden och det finns potential att utrota även BRSV. Genom en ökad förståelse för biosäker-het och hur ventilation av mikromiljöer, gruppstorlek och ålderssammansättning påverkar smittrycket och luftvägshälsan hos kalvar kan byggnader och management-rutiner som mini-merar risken för respiratoriska sjukdomar utformas..

This study had two different aims. The main aim was to investigate the dynamics and impact of African swine fever (ASF) on a farm in Uganda during a recent outbreak through a case study. The second aim was to estimate the presence of two important differential diagnoses of ASF: Classical swine fever (CSF) and Porcine Reproduction and Respiratory syndrome (PRRS).The field and laboratory based case study of the farm level dynamics of ASF virus during a recent outbreak (October-December 2010) on a farm in the district of Mityana, Uganda, was conducted, using interviews, ELISA and RT-PCR. The financial impact on the farm was also estimated. The impact of the outbreak was profound.

Dysfunction of the upper respiratory tract is a common cause of impaired performance and intolerance to exercise in racehorses and include several upper airway obstructions. The ones termed dynamic obstructions are primarily seen during physical exertion and affected horses often appear to be normal during endoscope examination at rest. The correlation between diagnoses made at rest respectively exercise is low, suggesting that an examination at rest alone is likely to be insufficient. The upper respiratory tract is exposed to great differences in pressure throughout the respiratory cycle; variations that are further altered during strenuous exercise and affect the rigidity of upper airway structures. In presence of great fluctuations in pressure, stability is achieved through coordinated and synchronous neuromuscular mechanisms. Due to nerve damage or anatomical abnormalities, these functions may be disrupted and further cause a dynamic collapse of the upper respiratory tract when pressure changes become too severe. The etiology behind the neuromuscular dysfunction is not yet fully understood.

ABSTRACT Tobacco Rattle Virus (TRV) is a soilborne plant virus. It is an important pathogen in potatoes where it causes spraing disease. This disease can lead to significant economical loss for the farmer, so it is imperative to get the proper diagnose before planting. TRV is spread naturally by free-living nematodes (Trichodorus and Paratrichodorus). Transference of TRV to a plant occurs when the virus-carrying nematodes feed on plant roots. The relationship between virus, nematodes and plants is complicated, and has to these days not been fully characterized. The diagnostic methods available today do not work sufficiently.

The purpose of the study was to investigate whether or not Icelandic horses are less severely affected in clinical symptoms of cough or decreased performance than other breeds of horses. A breed variation in chronic respiratory disease severity was suspected based on clinical experience at the Institution for surgery & medicine, large animal, SLU Uppsala. A retrospective journal study of 17 Icelandic horses and 17 Swedish Standardbred horses with chronic problems with cough and/or decreased performance compared several measurements of disease severity. The clinical signs, physical examination and laboratory testing results compared were respiratory rate, abdominal breathing, lung auscultation, endoscopy results, broncho-alveolar lavage (BAL) results and the blood gases pO2 and pCO2. All parameters were available for all 34 individuals except for the blood gases, which were analysed, in only four Icelandic horses and four Swedish Standardbred horses. The only parameters that appeared different between the two groups were respiratory rate and pO2. The four Icelandic horses, which had blood gases analysed, had more severe hypoxemia.