Serologic progression studies using CF and ELISA for the detection of antibodies against Eperythrozoon suis infection of swine

Serological studies by means of a CF-Test and Elisa were undertaken for evaluation of antibody titers against Eperythrozoon suis infection in swine. The animals were partly splenectomized and underwent artificial infection. It could be shown that the splenectomized animals showed higher and longer lasting antibody titers than the non splenectomized swine. It is stated, that the above mentioned tests can be used in diagnosis on a herd basis but not on a single animal basis.     

Propionate loading test for liver function in spontaneously ketotic dairy cows

Propionate utilisation by the liver in spontaneously ketotic dairy cows was investigated by determining blood glucose levels after an intravenous sodium propionate load (2.5 mmol kg-1). In addition, blood ketone body concentrations were measured after propionate loading. Cows were divided into three groups (control, mildly ketotic and severely ketotic) by their blood acetoacetate concentrations. Plasma glucose concentrations increased significantly after sodium propionate injection in all three groups (P less than 0.05). The maximum glucose concentration occurred earlier in the control group than in the ketotic groups. Changes in glucose concentrations following propionate loading of control and ketotic cows differed significantly at 20 minutes and beyond. Differences in the change in glucose concentration between mildly ketotic and severely ketotic cows were not significant. Acetoacetate concentration was significantly decreased at five minutes and beyond after the injection in ketotic cows, whereas beta-hydroxybutyrate concentration decreased more slowly. A decrease in beta-hydroxybutyrate concentration was significant at 40 minutes and beyond in the severely ketotic group and at 10 minutes and beyond in the mildly ketotic group after loading.     

The first appearance of infectious hemorrhagic disease of rabbits in Austria

In three Austrian rabbit units (two in the west, one in the east) heavy losses occurred in April/May 1989. The clinical course (deaths in adult animals, haemorrhagic diathesis) of the disease was indicative for an infection with the RHD-virus. Necropsy confirmed the suggestive clinical diagnosis as bleeding of the nostrils, hyperaemia in the respiratory tract, spleen tumor, partly decolorized livers, hyperaemia of kidneys with rare petechias could be observed. Histologic examination revealed centrolobular liver necrosis, lung bleeding and edema, tumor of spleen and atrophy of spleen follicles. Rabbits infected with organ suspensions died within 48 hours. The organ suspensions and the suspensions of the already necropsied animals showed a haemagglutination titer for above 1:100. This reaction could be inhibited with a specific RHD-antiserum. The intramuscular application of a RHD-reference strain in one hare, two wild rabbits and a rabbit did not induce clinical disease or death of the leporids during a six week observation period. The rabbit died within 48 hours post infection. However the hare and wild rabbits showed high antibody titers by ELISA at the end of the observation period. Before infection the two wild rabbits were serologically negative.     

Serological studies of antibodies against maedi-visna virus in sheep in Austria

883 sheep from 68 flocks were tested for the prevalence of antibodies against Maedi/Visna-(M/V)virus. As serological method the Agar Gel Immunodiffusion Test (AGID) was performed, 9.5% of the blood samples were positive against M/V, 1.7% showed questionable results. The highest incidence of serum-antibodies showed the Texel (47.7%) and Milk sheep (26.1%). No antibody titers were found in Mountain and Suffolk sheep. Merino sheep had antibody titers against M/V in 2.6% and Mountain sheep crossbreeds in 1.7%.     

Testing in swine of meal extracted from winter rapeseed with different glucosinolate content with regard to iodine supply. 1. Characterization of rapeseed extraction particles and fattening results

In a feeding experiment with 48 growing pigs 16% high glucosinolate rapeseed meal (HGRSM) (136 mumol glucosinolates + aglucones/kg dry matter, DM) or low glucosinolate (LG) RSM (48 mumol glucosinolates + aglucones/kg DM) in the feed were compared with 14% soya-bean meal (SBM) in each case. It were established 24 pairs of animals, which received the same quantity of the isonitrogenous but not isocaloric diets with SBM and the both RSM (pair fed). Four of the 2.12 animal pairs were not given supplementary I, four received 0.25 mg supplementary I/kg feed. Further four animals which were fed on LGRSM or HGRSM were provided with 0.0625 or 1 mg supplementary I/kg feed. In case of high glucosinolate intake (HGRSM) the lacking I supplementation decreased feed intake and growth and led to remarkable I deficiency symptoms from the fifth week onwards. The 2/3 lower glucosinolate dosage of the LGRSM diet also decreased performance and provoked I deficiency, however significantly later. The investigated I dosages (greater than 0.0625 mg/kg feed) did not effect the performance. In the experiment the eight animals which received LGRSM with supplementary I consumed 13% more feed than animals fed on HGRSM (P less than 0.05). The additional weight gain was 20% (P less than 0.05). Comparing the live weight gain of the SBM and RSM fed animals (pair fed) there was a significant increase of 9% versus the HGRSM groups and 5% versus the LGRSM groups.     

Use of staggered panels in sampling designs to increase the efficiency of estimating the number of incident cases of diseases in food animal populations

Sampling herds in staggered panels is proposed as a way to increase the precision of estimates of the number of incident cases of diseases in food animal populations. A components of variance model is offered as a parsimonious alternative to the somewhat intractable model underlying staggered-panel sampling. Evaluation of these methods using California National Animal Health Monitoring System data showed a gain in efficiency with staggered panel for seven of the eight diseases studied with little loss in efficiency for the eighth condition. The components of variance model was able to predict the gain in efficiency.     

Sero-epidemiological and pathological studies on enzootic bovine leukosis in Turkey.

The prevalence of enzootic bovine leukosis (EBL) in Turkey was investigated by serological screenings using the agargel immunodiffusion test (AGID). A total of 4,047 blood samples obtained from 2,780 cattle between one and 14 years of age and taken in 6-8 month-intervals in three dairy farms were tested for the presence of EBL-specific antibodies. A high prevalence of EBL-sero-positive animals was found amongst cattle in two of the farms. Furthermore, recommendations based upon the regulation implemented by an expert group of the European Commission and considering the local dairy management conditions were presented.