Evidence of Muscovy duck parvovirus in Muscovy ducklings in California

Muscovy duck parvovirus (MDPV) has been demonstrated in tissue samples from one- to four-week-old commercially reared Muscovy ducks that were weak, unable to walk and had a high mortality rate. On postmortem examination, the thigh and leg muscles, and the myocardium were found to be pale, and there was a fibrinous exudate on the capsule of the liver, and ascites. The parvovirus was isolated in embryonated Muscovy duck eggs and visualised by negative stain electron microscopy, detected by polymerase chain reaction (PCR) directly from the tissues, and antibodies to it were detected by immunoelectron microscopy, ELISA and immunofluorescence. In addition, the PCR products obtained that represented 1625 bp (74 per cent) of the capsid vP1 gene, including a hypervariable region between Derzsy's disease virus or goose parvovirus and MDPV, were sequenced and shown to be 100 per cent homologous with the MDPV 89384 reference strain, but only 82.3 per cent homologous with Derzsy's disease virus.     

Comparison of Pseudomonas aeruginosa isolates from mink by serotyping and pulsed-field gel electrophoresis

Isolates of Pseudomonas aeruginosa from clinical infections in mink were subjected to serotyping and pulsed-field gel electrophoresis (PFGE) using SpeI. A total of 212 isolates of P. aeruginosa from the year 1998 to 2001 were included in this study: 168 isolates from mink obtained from 74 farm outbreaks of haemorrhagic pneumonia. Isolates from mink were separated into 34 distinct clones by PFGE subtyping. All isolates from mink infected during the same farm outbreak were identical, except in one case where two different strains were isolated from mink obtained from the same farm outbreak. P. aeruginosa of specific PFGE types were found to cause clusters of outbreaks on several farms within a few weeks of each other. However, PFGE types of strains causing clusters of farm outbreaks changed from year to year. These results suggest that some outbreaks of haemorrhagic pneumonia are caused by pathogenic strains of P. aeruginosa spread between farms and animals either mechanically, or through feed or water from a common source, rather than by random nosocomial infections with strains from the farm environment.     

Genomic sequences of low-virulence avian paramyxovirus-1 (Newcastle disease virus) isolates obtained from live-bird markets in North America not related to commonly utilized commercial vaccine strains

Avian paramyxovirus 1 (APMV-1), also referred to as Newcastle disease virus (NDV), variants of low virulence were isolated from chickens, ducks and other unidentified species found in live-bird markets of the northeastern United States. These isolates were characterized as APMV-1 by the hemagglutination-inhibition (HI) assay utilizing NDV-specific polyclonal antisera. However, the isolates failed to react with a monoclonal antibody that has specificity for a wide variety of APMV-1 isolates. Although only highly virulent isolates require reporting to international regulatory agencies, the ability to correctly identify APMV-1 types is important for control and regulatory purposes. Protein gel patterns of the purified isolates resembled previously reported APMV-1 and anti-NDV polyclonal sera recognized the viral proteins. For three isolates oligonucleotide primers specific for the nucleoprotein, fusion protein and polymerase genes of NDV were utilized to synthesize cDNA using viral RNA as a template. Approximately 12kb of the genome was subsequently sequenced for the three isolates that included the nucleoprotein, phosphoprotein, matrix protein, fusion (F) protein, hemagglutinin-neuraminidase protein genes and a 5' portion of the polymerase gene. The isolates had an F protein cleavage site sequence of ERQER/LVG indicating low-virulence viruses that phylogenetically separated with other unique NDV isolates designated as a lineage 6 genotype. Additionally, a four amino acid insert was detected in the predicted phosphoprotein which complies with the "rule of six" among paramyxoviruses. These APMV-1 genotypes have not been previously reported in North America and further substantiate the heterogeneous genetic nature of these commercially important pathogens found worldwide.     

The Effect of Blood Sampling on Plasma Cortisol in Female Reindeer (Rangifer tarandus tarandus L)

A major response of the body to stress is the secretion of adrenocorticotrophic hormone (ACTH) by the adenohypophysis resulting in increased blood Cortisol levels. Corticotropin releasing factor (CRF) controls the release of ACTH, mediating a direct effect at the level of the pituitary (Guillame et al. 1992). An animal''s perception of a stressful event and the resulting increase in Cortisol production can be influenced by previous experience, season, time of day, and the animal''s sex, age, and condition (Dantzer & Mormède 1983, Moberg 1985).     

Effect of cumulus cells and sperm concentration on fertilization and development of pig oocytes

Effect of sperm concentrations and cumulus cells (CCs) on porcine IVF was re‐evaluated using current improved IVM and IVC system. Our results showed that both CCs and sperm concentration had significant effect on penetration rate, frequency of polyspermy and embryonic development. The best IVF results were obtained with oocytes with CCs fertilized with 0.5 × 10⁵ sperm/ml. Such an IVP system works on both sow and gilt oocytes.     

Comparison of the Distribution and Occurrence of Fusarium graminearum and Deoxynivalenol in Hard Red Winter Wheat for 1993-1996

Hard red winter wheat samples collected from different locations in Kansas from the 1993, 1994, 1995, and 1996 harvests were plated to determine Fusarium graminearum infection and analyzed for deoxynivalenol by thin-layer and gas chromatography. Rainfall, temperature, and cultivar were important factors affecting the severity of F. graminearum infection as well as deoxynivalenol production. The 1993 and 1995 growing seasons had high percentages of samples infected with F. graminearum and contaminated with deoxynivalenol. Averaged over the four years, cultivars 2163 and Karl had significantly higher levels of infection than did TAM 107. These widely grown cultivars were used in comparison. Northeastern Kansas had the highest levels of F. graminearum infection and deoxynivalenol contamination but also had the lowest acreage planted to hard red winter wheat.