Hyperostotic polyarthropathy in a rabbit - a suspected case of chronic hypervitaminosis A from a diet of carrots

Chronic hypervitaminosis A can occur in many species after excessive dietary intake of Vitamin A (retinol). The most common presentation of chronic hypervitaminosis A is a polyarthropathy with hyperostosis and ankylosis of various joints. This case report describes a probable case of naturally occurring hypervitaminosis A-induced polyarthropathy in a rabbit after chronic ingestion of a diet made up almost exclusively of carrots. Carrots do not contain retinol, but are rich in provitamin A (or beta-carotene). Rabbits are unique in that they can convert 100% of dietary beta-carotene into retinol. A syndrome of naturally occurring hypervitaminosis A-induced polyarthropathy has not been described in a rabbit before.     

Local Effect of the Corpus Luteum on Ovarian Follicular Functional and Morphological Features in the Goat

Ovaries of unilaterally ovulated goats (n=21) were used to study follicular morphological features (proportion and degree of atresia, oestradiol production in vitro and progesterone production of granulosa cells in culture). Follicles were dissected out and classified as small (1–2 mm), medium (2–4 mm) and large (>4 mm). Morphological and physiological features were compared in each size class between ovaries bearing and not bearing corpora lutea (CLO and NCLO, respectively). Within the same size class, there was no difference in proportion or in degree of atresia, between CLO and NCLO. A significant effect of follicular size on oestradiol production in vitro was detected, but no effect of the corpus luteum was found. Finally, progesterone production of granulosa cells in culture was significantly higher in CLO than in NCLO after 24 h (p < 0.05) and also after 90 h (p < 0.01) of culture. This higher progesterone production by CLO granulosa cells in culture could be explained by local influence of the corpus luteum stimulating the steroidogenic activity but not aromatase activity. Further studies are needed to clarify possible factors and pathways for this local effect of the corpus luteum upon follicular physiology.     

Characterisation of porcine haemophili isolated from Australian pigs between 1988 and 1992

SUMMARY A total of 362 haemophili, isolated from pigs throughout Australia, were characterised by phenotypic properties. Most were identified as Actinobacillus pleuropneumoniae (296 isolates) or Haemophilus parasuis (52 isolates). The remaining isolates were identified as Haemophilus Taxon ‘minor group’ (12 isolates) and Haemophilus Taxon D (two isolates). All 296 A pleuropneumoniae isolates were serotyped by slide agglutination and/or gel diffusion, using rabbit antisera against all 12 recognised serovars. Of these, only 156 (52.7%) could be assigned to a single serovar as follows: serovar 1–85 isolates, serovar 2–4 isolates, serovar 3–2 isolates, serovar 5–10 isolates, serovar 7–51 isolates, serovar 11–2 isolates and serovar 12–2 isolates. Of the remaining 140 isolates, 91 gave cross-reactions with serovars 3 and 6, one cross-reacted with serovars 9 and 10, one cross-reacted with serovars 9 and 11 whereas 47 gave no reaction with any of the antisera.     

Enrichment of gene-coding sequences in maize by genome filtration

Approximately 80% of the maize genome comprises highly repetitive sequences interspersed with single-copy, gene-rich sequences, and standard genome sequencing strategies are not readily adaptable to this type of genome. Methodologies that enrich for genic sequences might more rapidly generate useful results from complex genomes. Equivalent numbers of clones from maize selected by techniques called methylation filtering and High C0t selection were sequenced to generate approximately 200,000 reads (approximately 132 megabases), which were assembled into contigs. Combination of the two techniques resulted in a sixfold reduction in the effective genome size and a fourfold increase in the gene identification rate in comparison to a nonenriched library.     

Presence of Maedi Visna Virus (MVV)‐Proviral DNA in the Genital Tissues of Naturally Infected Ewes

Maedi Visna virus (MVV) causes progressive degenerative inflammatory disease in multiple organs including the lungs (pneumonia, ‘maedi’), mammary gland, joints and nervous system (meningoencephalomyelitis, ‘visna’) in sheep. Maedi Visna Virus has been detected in macrophages of several tissues and epithelial cells in vivo: bone marrow, cells of the central nervous system, lung and bronchial tissues, milk epithelial cells recovered from milk samples and epithelial cells of mammary tissue. However, the presence of MVV in the genital tracts of naturally infected ewes has not previously been studied. The aim of this study was to use nested‐PCR, targeting the gag gene, to determine whether genital tissues (ovaries, oviducts and uterus) from 83 ewes originating from various breeding herds in the South‐East of France were positive for MVV‐proviral DNA. Peripheral blood mononuclear cells (PBMC) tested positive for MVV‐proviral DNA, using nested‐PCR analysis, in 57.8% of ewes (48/83). The provirus was also identified in 47% (78/166) of the ovaries, 38.6% (64/166) of the oviducts and 45.8% (38/83) of the uteri sampled. These findings clearly demonstrate, for the first time, that tissue samples from the genital tract of ewes (ovary, oviduct and uterus) can be infected with MVV. This suggests that there is a risk of vertical and/or horizontal transmission of MVV during embryo transfer from embryos produced in vivo or in vitro.     

Measurement of Parity Nonconservation and an Anapole Moment in Cesium

The amplitude of the parity-nonconserving transition between the 6S and 7S states of cesium was precisely measured with the use of a spin-polarized atomic beam. This measurement gives Im(E1pnc)/beta = -1.5935(56) millivolts per centimeter and provides an improved test of the standard model at low energy, including a value for the S parameter of -1.3(3)exp (11)theory. The nuclear spin-dependent contribution was 0.077(11) millivolts per centimeter; this contribution is a manifestation of parity violation in atomic nuclei and is a measurement of the long-sought anapole moment.     

Comparison of Membrane‐Permeant Fluorescent Probes for Sperm Viability Assessment in the Ram

This study was designed to compare the effectiveness and usability of four permeant fluorochromes (CFDA; SYBR‐14; Hoechst‐33342; and acridine orange), combined with propidium iodide to assess sperm membrane integrity. Three different experiments were conducted. The first trial was designed to study the optimal dye concentration and minimum incubation time required to achieve optimum fluorescence intensities and contrast for each fluorochrome combination using ram fresh semen samples. Both SYBR‐14 and acridine orange allowed a direct assessment of sperm membrane integrity, without the need of incubating samples, whereas a minimum of 4 and 6 min of incubation at 37°C was necessary to achieve optimum fluorescence intensities in the CFDA and Hoechst groups, respectively. In the second trial, fresh semen samples were mixed with different volumes of membrane‐affected sperm (semen treated with three cycles of freezing to ?20°C and thawing at room temperature) to produce semen samples with known proportions of damaged spermatozoa. The results were compared with the theoretical values predicted on the basis of the estimations made on fresh and frozen samples. The proportions of damaged sperm in each sample determined using the four fluorochrome combinations agreed with the predicted theoretical values, with the acridine orange/propidium iodide providing the best adjustment. The third experiment was performed to compare the results of sperm membrane integrity using the four fluorochrome combinations. The proportions of plasmalemma‐intact sperm determined by acridine orange and SYBR‐14 were greater (p < 0.0001) than the proportions of intact sperm determined by CFDA and Hoechst stains. It was concluded that the most efficient combinations to be used in ram sperm were AO/PI and SYBR/PI because it allowed a direct assessment of sperm viability without the need to incubate samples and obtaining reliable results.