The effect of copper on the response of lambs to selenium supplementation when grazing a selenium deficient pasture

Two trials were undertaken with lambs grazing selenium deficient pasture to determine if copper would enhance liveweight and fleece-weight responses to selenium supplementation. In the first trial, lambs given selenium or selenium plus copper gained significantly more weight and had higher fleece-weights after 260 days than did control lambs or lambs given copper alone. Copper given alone or together with selenium had no significant effect on liveweight or fleece-weight when compared with control lambs and lambs that were given selenium alone respectively. This finding was confirmed in a second trial when growth and fleece-weights of selenium and selenium plus copper treated lambs were compared and no significant differences found. In both trials copper significantly raised liver copper levels. In selenium supplemented but not in selenium deficient sheep, copper significantly increased blood selenium levels.     

Guttural pouch mycosis in a 6-month-old filly

A 6-month-old filly was presented with unilateral epistaxis. Based on clinical signs, endoscopic examination, and postmortem examination, guttural pouch mycosis was diagnosed. The young age of the filly and the fact that this was the 2nd diagnosis of guttural pouch mycosis on this farm was unusual.     

Nucleotide Sequencing and Analysis of 16S rDNA and 16S-23S rDNA Internal Spacer Region (ISR) of Taylorella equigenitalis, as an Important Pathogen for Contagious Equine Metritis (CEM)

The primer set for 16S rDNA amplified an amplicon of about 1500 bp in length for three strains of Taylorella equigenitalis (NCTC11184^T, Kentucky188 and EQ59). Sequence differences of the 16S rDNA among the six sequences, including three reference sequences, occurred at only a few nucleotide positions and thus, an extremely high sequence similarity of the 16S rDNA was first demonstrated among the six sequences. In addition, the primer set for 16S-23S rDNA internal spacer region (ISR) amplified two amplicons about 1300 bp and 1200 bp in length for the three strains. The ISRs were estimated to be about 920 bp in length for large ISR-A and about 830 bp for small ISR-B. Sequence alignment of the ISR-A and ISR-B demonstrated about 10 base differences between NCTC11184^T and EQ59 and between Kentucky188 and EQ59. However, only minor sequence differences were demonstrated between the ISR-A and ISR-B from NCTC11184^T and Kentucky188, respectively. A typical order of the intercistronic tRNAs with the 29 nucleotide spacer of 5'-16S rDNA-tRNA^Ile-tRNA^Ala-23S rDNA-3' was demonstrated in the all ISRs. The ISRs may be useful for the discrimination amongst isolates of T. equigenitalis if sequencing is employed.     

Cereal Grain Structure and Development: Some Implications for Quality

The grains of cultivated grasses that are conventionally described as cereals share many structural and developmental features. At the same time they are distinguished, one from another, by many individual characteristics, which fit them for different types of processing. In this review an attempt is made to describe common characteristics and to identify significant variables, both among and within species, that influence the grains» fitness for processing. A fruit is defined by every component part, but research has been concentrated disproportionately on those components perceived as being of greatest importance. For the continuation of the species the only essential component is the embryo, but for exploitation by humans the largest component, the endosperm, is the most important. It is inevitable that this review reflects the uneven emphasis of the literature on which it is based. A further justification for the bias is the potential that endosperm offers, by virtue of its simplicity, as a model whereby fundamental mechanisms of cell behaviour and control might be elucidated. This has already been recognised by a few but benefit may result from its wider appreciation.     

Molecular diversity of Campylobacter coli and C. jejuni isolated from pigs at slaughter by flaA-RFLP analysis and ribotyping

A population of porcine isolates of Camplobacter jejuni (n = 11) and C. coli (n = 17) were examined for genotypic relatedness employing ribotyping, as well as polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the flagellin (fla)A gene locus. PCR was employed to amplify a 533 bp fragment from the flaA gene, including the previously described short variable region (SVR), employing the novel primers, A2 and Al and successfully generated this amplicon for all wild-type strains examined (n = 28) of both C. jejuni and C. coli, as well as with both type strains, i.e. C. jejuni NCTC 11351 and C. coli NCTC 11366. Individual genotypes were assigned to each isolate typed employing the four typing methods (flaA-RFLP(Hae) III, flaA-RFLP(Pst) I ribotyping(Hae) III and ribotyping(Pst) I) and were assigned an arbitrary genotype code in ascending alphabetical order in comparison with a database of established genotypes for each of the methods employed. This study showed that several flaA-RFLP and ribopatterns existed within C. jejuni and C. coli, and demonstrated a heterogeneous diversity of strains occurring in the pigs examined. Ribotyping of strains with 16S and 23S rRNA with Pst I and Hae III digested chromosomal DNA allowed subdivision of strains into nine and eight groups, respectively. RFLP analyses with Pst I and Hae III digests probed with the flaA gene probe allowed subdivision of strains into eight and eleven subtypes, respectively. Employment of RFLP with the flaA nucleic acid probe and Hae III digests produced the greatest amount of variation of any genotyping scheme employed. Although there was a high degree of variability demonstrated by both typing methods, most isolates ( > 60%) clustered into four main genotypes, i.e. genotypes A-D. FlaA-PCR-RFLP typing demonstrated that the majority of isolates, 67.9 and 60.7%, were included in these four main genotypes for Pst I and Hae III restriction digests, respectively, although there was a high prevalence (7/11; 63.6%) of fla(Hae) III genotype A occurring within the C. jejuni isolates. Likewise, ribotyping studies demonstrated that most isolates were clustered into these four main genotypes, accounting for 81.5 and 60.7% of isolates for Pst I and Hae III restriction digests, respectively. This may indicate that the clonal population of campylobacters within this pig population is largely composed of persistent and dominant types, with a smaller number of hypervariable subtypes. Such data may useful in determining epidemiological routes of transmission of campylobacters from animal to animal, as well as helping to identify virulence determinants in persistent subtype populations.