The Fusarium graminearum genome reveals a link between localized polymorphism and pathogen specialization

We sequenced and annotated the genome of the filamentous fungus Fusarium graminearum, a major pathogen of cultivated cereals. Very few repetitive sequences were detected, and the process of repeat-induced point mutation, in which duplicated sequences are subject to extensive mutation, may partially account for the reduced repeat content and apparent low number of paralogous (ancestrally duplicated) genes. A second strain of F. graminearum contained more than 10,000 single-nucleotide polymorphisms, which were frequently located near telomeres and within other discrete chromosomal segments. Many highly polymorphic regions contained sets of genes implicated in plant-fungus interactions and were unusually divergent, with higher rates of recombination. These regions of genome innovation may result from selection due to interactions of F. graminearum with its plant hosts.     

Light intensity and fur-chewing in rabbits

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Madam:-, Fur-chewing is a relatively common apparent behavioural problem of farmed rabbits. Unlike the preparturient doe, who pulls out fur from ventral body surfaces to line her nest, rabbits of either sex which fur-chew, bite off hair from any part of the body which is accessible and may partially denude more than 50% of their body surface. The condition often appears to be self-inflicted, and unlike whisker chewing in mice, or feather plucking in chickens, a rabbit may either chew its own fur or that of others. The condition is a serious problem for commercial producers of rabbit pelts and for those attempting to carry out nutritional studies which require analysis and comparison of food intake and faecal output. For instance, in digestibility studies, fur-chewing constitutes a confounding variable in relation to nitrogen analysis.     

The use of a T-maze to measure cognitive–motor function in cats (Felis catus)

Few tests have been developed to evaluate the cognitive and motor capabilities of domestic cats, despite the suitability of cats for specific studies of neuroanatomy, infectious diseases, development, aging, and behavior. The present study evaluated a T-maze apparatus as a sensitive and reliable measure of cognition and motor function in cats. Eighteen purpose-bred, specific pathogen-free, male, neutered domestic short-haired cats (Felis catus), 1-2 years of age, were trained and tested to a T-maze protocol using food rewards. The test protocol consisted of positional discrimination training (left arm or right arm) to reach a predetermined criterion, followed by 2 discrimination reversal tests. The 2 reversal tests documented the ability of the subjects to respond to a new reward location by switching arms of the T-maze. Data were collected on side preference, number of correct responses, and latency of the responses by the subjects. Aided by a customized computer program (CanCog Technologies), data were recorded electronically as each cat progressed from the start box to the reward arm. The protocol facilitated rapid training to a high and consistent level of performance during the discrimination training. This learning was associated with a decrease in the latency to traverse the maze to a mean of 4.80 ± 0.87 seconds, indicating strong motivation and consistent performance. When the rewarded side was reversed in the test phase, the cats required more trials to reach the criterion, as expected, but again showed reliable learning. The latency to the reward in the first session of reversal increased 86% from the first to the last trial, indicating that it may provide a useful index of cognitive processing. Latencies subsequently decreased as the new reversal paradigm was learned. This paradigm provides a relatively rapid and reliable test of cognitive–motor performance that can be used in various settings for the evaluation of feline cognitive and motor function.     

Another dolphin in peril? Photo‐identification,occurrence, and distribution of the endangered Indian Ocean humpback dolphin (Sousa plumbea) in Algoa Bay

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WHOLE-CROP VICIA FABA FOR CONSERVATION. A COMPARISON BETWEEN WINTER-, HORSE-, TICK-, AND BROAD-BEAN CULTIVARS

A trial containing cultivars of Vicia faba var. equina, minor and major was harvested as a whole-crop in 1971. The aim was to estahlish the DM yield obtainahle from a selection of spring-hean cultivars and evaluate this in relation to previously reported yields from winter heans. DM yields ranged from 48 to 86 hkg/ha over the three cutting dates. Significant differences were found hetween cv. in digesdhiUty, the range being 54 to 71%, and one hroad-hean cv. was shown to have a high digestihility at all cuts. Crude-protein contents of 13 to 19% were recorded. Percentage DM rose from 16 to 18% at the first cut to 23 to 45% at the third, hroad-hean cv. rising more slowly than horse- and dck-hean cv. Spring-bean cv. had a lower DM yield than winter cv. Horse hean was superior to tick bean in DM yield, percentage DM, and D-value. Broad-bean cv. proved difficult to dry and therefore may be more suitable for ensilage than dehydradon.     

Arsenic(III) fuels anoxygenic photosynthesis in hot spring biofilms from Mono Lake, California

Phylogenetic analysis indicates that microbial arsenic metabolism is ancient and probably extends back to the primordial Earth. In microbial biofilms growing on the rock surfaces of anoxic brine pools fed by hot springs containing arsenite and sulfide at high concentrations, we discovered light-dependent oxidation of arsenite [As(III)] to arsenate [As(V)] occurring under anoxic conditions. The communities were composed primarily of Ectothiorhodospira-like purple bacteria or Oscillatoria-like cyanobacteria. A pure culture of a photosynthetic bacterium grew as a photoautotroph when As(III) was used as the sole photosynthetic electron donor. The strain contained genes encoding a putative As(V) reductase but no detectable homologs of the As(III) oxidase genes of aerobic chemolithotrophs, suggesting a reverse functionality for the reductase. Production of As(V) by anoxygenic photosynthesis probably opened niches for primordial Earth's first As(V)-respiring prokaryotes.     

Seroepidemiologic survey of antibodies to Ehrlichia equi in horses of northern California

The prevalence of antibodies to Ehrlichia equi in horses from the foothill regions of northern California and from the Sacramento valley (non-foothill area) was determined, using an indirect fluorescent antibody test. Horses from foothill regions had a higher prevalence of seropositivity (10.4%) and higher titer (1:10 to 1:80) than did those from non-foothill regions (3.1%; titer less than or equal to 1:10). Fifty percent of healthy horses on a foothill farm enzootic for E equi had titer to E equi, suggesting that infection with E equi can be subclinical. Six veterinarians surveyed from northern California diagnosed clinical E equi infection in 38 horses during 1985-1986 based on clinical signs of infection and observation of E equi inclusion bodies in neutrophils on blood smears.     

Diagnostic laparoscopy in the horse

Laparoscopy was performed in 5 clinically normal horses. Abdominal fluid protein content and WBC count increased markedly in all horses. Necropsy findings were confined to an increased amount of slightly turbid abdominal fluid. Five examples of applications of laparoscopy in horses with abdominal problems indicated that laparoscopy can be a valuable diagnostic procedure in the horse.     

Bilateral renal dysplasia with nephron hypoplasia in a foal

Bilateral renal dysplasia and nephron hypoplasia was diagnosed in a Quarter Horse foal with clinical signs of lethargy, convulsions, and diarrhea. Laboratory evaluation revealed anemia, hypoproteinemia, leukopenia, hyponatremia, hypochloremia, and hyposmolality. The foal also had high concentrations of serum creatinine, BUN, and phosphorus. Evaluation of urinary indices revealed a high ratio of urinary gamma-glutamyl-transferase activity to concentration of creatinine, as well as a high fractional clearance ratio of sodium and potassium. Intravenous treatment with saline solution (0.9% NaCl) and antimicrobials provided only temporary resolution of some of the abnormalities. Diagnosis was partly established by histologic evaluation of renal tissue obtained via an ultrasonographically guided biopsy and was confirmed at necropsy. Pathologic changes in the kidney were unique in that the size of the kidneys, along with the appearance and number of glomeruli, were essentially normal despite marked hypoplasia of nephron tubules in the medulla.