Experimental Toxoplasma gondii infection leading to fatal enteritis in reindeer (Rangifer tarandus).

Two, 50-60-kg yearling reindeer (Rangifer tarandus) were inoculated intraruminally with 5,000 (reindeer 1) or 50,000 (reindeer 2) oocysts of the ME-49 strain of Toxoplasma gondii. Both reindeer became ill day 4 postinoculation (p.i.

No rabies detected in voles and field mice in a rabies-endemic area.

Brain samples were collected from 514 voles and wild mice in Estonia, and examined for rabies. The samples were tested with antigen ELISA, and 8.6% of them additionally by virus isolation assay.

Efficacy of a commercial competitive exclusion product against a chicken pathogenic Escherichia coli and E coli O157:H7.

The prevention of caecal colonisation of chicks by a poultry pathogenic Escherichia coli O20:K-:H8 and the human pathogenic E coli O157:H7 was studied in vivo in four one-week laboratory trials. Chicks were treated with a competitive exclusion product on the day of hatch and challenged one day later. The poultry pathogenic serotype showed higher levels of caecal colonisation than the human pathogenic serotype, but the protection against both pathogens was highly significant.

Note: inhibition of the growth of Yersinia enterocolitica O:3 by the microflora of porcine caecum and ileum in an in vitro model.

The growth of Yersinia enterocolitica O:3 was tested in an in vitro model of the porcine intestine at the physiological temperature of 39 degrees C of growing pigs. The model supported a stable population of Y. enterocolitica at a level 10(8)-10(9) cells ml-1.

The first Salmonella enteritidis phage type 1 infection of a commercial layer flock in Finland.

The first Salmonella Enteritidis phage type (PT) 1 infection in a commercial layer flock of 2700 birds in Finland occurred in 1995. All the birds were ordered to be killed, the eggs to be destroyed and access to the layer house was denied in order to prevent spread of the infection. Ninety one commercial layers, 61 replacement pullets and 1062 eggs were collected for the analyses.

A Less Hazardous Enrichment Broth for Listeria without Cycloheximide and Acriflavine.

The hazardous substances cycloheximide and acriflavine are used as selective agents in standard listeria enrichment broths. This study was undertaken to develop a less hazardous listeria enrichment broth in order to avoid occupational-safety and waste-management problems. The replacement of cycloheximide (50 mg/l) and acriflavine (15 mg/l) with natamycin (25 mg/l), moxalactam (10 mg/l) and bacitracin (20 mg/l) did not inhibit the growth of Listeria monocytogenes .

Influence of route of administration on the plasma concentrations of ivermectin in reindeer.

The concentration of ivermectin in the plasma of reindeer was measured after it was administered either topically as a pour-on preparation at 500 micrograms kg-1 bodyweight at different seasons to animals of different ages, or after subcutaneous and oral doses of 200 micrograms kg-1 bodyweight. The plasma concentrations of ivermectin were highest and least variable after it was administered subcutaneously.

Characterization of clinical mastitis in primiparous heifers.

Using data from health records for cows in Finland from between 1983 and 1991, we investigated the general trend for frequency of mastitis in heifers, seasonal variation, breed differences, and etiology of the disease. The performance of the heifers was monitored during first lactation. Treatment of heifer mastitis, defined as mastitis treatment 1 wk before and 1 wk after calving, increased from 1.

Staphylococci in heifer mastitis before and after parturition.

Aseptic udder quarter secretion samples (n = 1112) from 200 mastitic and 65 non-mastitic control heifers from 160 different farms were collected for bacteriological examination and in vitro antimicrobial susceptibility testing. Coagulase-negative staphylococci (CNS) were the most frequently isolated bacteria (57.8%).

Influence of processing temperature on the formation of biogenic amines in dry sausages.

Temperature is known to have a clear influence on the formation of biogenic amines in the fishing industry and in cheese fermentation In this work, the effect of processing temperature on the formation of amines in dry sausages was studied in pilot and factory trials. Sausages made from the same batch of raw materials, were divided into two groups each fermented at different processing temperatures. The influence of raw materials on amine formation was evident.

Rabies antibodies in vaccinated dogs.

Forty-seven healthy, owned dogs were vaccinated with Madivak and 85 with Rabisin. Geometric mean titres of 17.40 and 1.

Actinobacillus pleuropneumoniae serotype-2 antibodies in sow colostrum in Finnish pig-health-scheme herds.

A direct ELISA with phenol-extracted antigen for Actinobacillus pleuropneumoniae serotype 2 was developed. The test was specific when tested with rabbit antisera prepared against different A. pleuropneumoniae serotypes.

Aspergillus arvii spec. nov., a new animal pathogen?

Aspergillus arvii sp. nov. Aho, Horie, Nishimura & Miyaji isolated from liver lesions of a dairy cow in Finland, is suggested to represent a new species.

Mortality associated with renal coccidiosis in juvenile wild greylag geese (Anser anser anser).

Fourteen non-flying wild greylag (Anser anser anser) goslings were reported dead on the Bothnian Bay coast of Finland in July and August, 1992. Renal coccidiosis caused by Eimeria truncata was isolated from all three of the goslings necropsied.

Stachybotrys atra Growth and Toxin Production in Some Building Materials and Fodder under Different Relative Humidities.

Growth of Stachybotrys atra and its toxin production on some building materials and in animal fodder were studied at relative humidities ranging from 78 to 100%. Toxins were detected by biological assays and chemical methods. Strong growth of the fungus and presence of macrocyclic trichothecenes, mainly satratoxins G and H, were detected on wallpaper and gypsum boards and in hay and straw at saturation conditions.

Differentiation of Salmonella serovar infantis isolates from human and animal sources by fingerprinting IS200 and 16S rrn loci.

We genotyped Salmonella serovar infantis (referred to as S. infantis), which is the most widespread serovar among animals and the third most common cause of human salmonellosis in Finland. Molecular fingerprinting of the 16S rrn locus and the Salmonella-specific insertion sequence IS200 was used to type the 131 isolates originating from the main sources of S.

Bovine clinical mastitis due to coagulase-negative staphylococci and their susceptibility to antimicrobials.

A total of 168 coagulase-negative staphylococci (CNS) strains were isolated from milk samples taken from cows with clinical mastitis. The samples were collected between January 1990 and August 1992 from cows in the veterinary surveillance area of the Ambulatory Clinic, College of Veterinary Medicine, Hautjärvi, Finland. In 100 cases the effect of antibiotic treatment was evaluated 3-4 weeks after initial sampling.

Antibacterial susceptibility of bovine-mastitis pathogens tested directly in milk from infected quarters.

Antibacterial susceptibilities of bovine-mastitis pathogens were analysed directly in 57 mastitic milk samples without inoculation with exogenous organisms. Aseptically collected milk was mixed with serial dilutions of antibacterials and the growth was observed using 2,3,5-triphenyltetrazolium chloride (TTC) reduction the following day. The results were compared with those obtained by using calibrated bacterial inocula in turbidimetric minimum-inhibitory-concentration (MIC) determination in broth cultures, and in TTC-broth culture-test and TTC-normal milk-test.

Histamine and Tyramine Production by a Lactobacillus Strain Subjected to External pH Decrease.

The preservative effect of fermentation is based on the pH decrease during processing. However, most studies conceming the influence of pH on the formation of biogenic amines have been made in broths with different initial pH values. A histamine- and tyramine-positive Lactobacillus strain isolated from dry sausage was added at an initial level of 3.

Protective effect of antioxidants against free radical-mediated lipid peroxidation induced by DON or T-2 toxin.

An experiment was conducted on rats to investigate the capacity of antioxidants to protect against acute toxicity caused by DON or T-2 toxin. Male rats were fed two different feeds. One group received a feed deficient in vitamins C and E and selenium, whereas the other group was fed with a feed enriched in antioxidants.

Effect of abrasion of teat orifice epithelium on development of bovine staphylococcal mastitis.

The predisposing effect of teat damage on mastitis caused by staphylococci and the pathogenicity of Staphylococcus aureus, Staphylococcus hyicus, and Staphylococcus epidermidis were investigated with an experimental model. The study included three experiments in which the teat canal orifice of 5 cows was slightly abraded. Experimental and control quarters were challenged with a staphylococcal suspension, and the status of the quarters was monitored.

Immunization of cattle against rabies using inactivated cell culture vaccines.

Twenty-one heads of cattle were vaccinated with Madibovin, 31 with Rabdomun and 127 with Rabisin on 4 different farms. Rabies neutralizing antibody titre (> or = 0.5 IU/ml) was detected in 80% of 163 animals tested about 1 month and in 42% of 133 animals tested about 1 year after primary vaccination.

Association af changes in the bacterial ecology of bovine mastitis with changes in the use of milking machines and antibacterial drugs.

The results of mastitis bacteriology made by the National Veterinary and Food Research Institute in Finland during the past 50 years (1.15 million samples) are viewed in relation to simultaneous changes in dairy cow management. Although intensive preventive measures have been applied for decades, the prevalence of bovine mastitis has not decreased.