Training in animal handling for veterinary students at Charles Sturt University, Australia

Charles Sturt University in New South Wales, Australia, is responding to a national need for veterinarians with the skills and attributes to fulfill roles in rural practice and the large-animal industries. Rural practitioners must competently and confidently handle a range of large animals if they are to build a relationship of mutual trust with clients and deliver effective animal-health services. Training in animal handling begins in the first year of the course with highly structured small-group practical classes involving cattle, horses, sheep, dogs, cats, pigs, poultry, and laboratory animals (rats and mice). Other experiences with animals in the first three years build on basic animal-handling skills while performing other veterinary activities. Students who provide documented evidence of prior animal-handling experiences are admitted, and learning and teaching strategies aim to enhance skills and knowledge. Rigorous examinations use a competency-based approach prior to extramural placements on farms and in veterinary practices. A continuing process of evaluation, review, and refinement will ensure continual improvement and graduate veterinarians with strong skills in animal handling.     

Identifying declines in waterbirds: The effects of missing data, population variability and count period on the interpretation of long-term survey data

To manage and conserve wildlife populations effectively it is necessary to use methods that identify the often non-linear trends in populations, have an inbuilt assessment of trend quality and can analyse count data from a range of spatial scales. We present a method of trend analysis using generalised additive models. These produce smoothed indices of abundance that can be used to assess population change from one or more sites or time periods, with any number of estimates of abundance per index period. We apply this method to count data collected under the Wetland Bird Survey, a national scheme that monitors waterbirds in the United Kingdom. To highlight declining populations, ‘alerts’ were raised if the population decline was equal to or greater than 50%. Significance was determined using bootstrapped confidence intervals for analyses that included many sites, or a novel Monte-Carlo method for single site analyses. The impact of missing data, species count variability and the number of months used to calculate the population change was greater at individual sites than for national datasets, which were relatively insensitive to changes in the above parameters. For single sites it is essential that three or more counts be made per index period if reliable estimates of population change are required. We propose that the method presented could be applied to a wide range of national or other monitoring schemes for a variety of taxa.     

Effect of soil pH on mineral element concentrations of two erythroxylum species

Erythroxylum coca var. coca Lam. (E. coca) and Erythroxylum novogranatense var. novogranatense (Morris) Hieron (E. n. novogranatense) are two of four Erythroxylum species grown in the tropics of South America for cultural medicines and the alkaloid benzoylmethylecgonine. In a published study of biomass production over a soil pH range of 3.5 to 7.0, E. coca grew best at a pH equal to and below 5.5, and E. n. novogranatense grew best within the pH range of 4.7 to 6.0. Erythroxylum coca was tentatively classified as more tolerant to metal toxicities [aluminum (Al) and manganese (Mn)] than E. n. novogranatense, however, concentration patterns of mineral elements for E. coca and E. n. novogranatense tissue have not been reported, nor have the mechanisms of differential acid‐soil‐tolerance been elucidated. In the current study, the effects of soil pH on concentrations of Al, calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), Mn, and zinc (Zn) in leaves, stems, and roots were investigated. At pH 3.5, roots of both species accumulated high concentrations of Al that decreased as soil pH increased, however, there was no pH × species interaction. The highest concentration of Ca was found in the leaves of both species, however, E. coca accumulated more Ca as soil pH increased than did E. n. novogranatense. Manganese and Zn levels were highest in roots of both species (E. coca and E. n. novogranatense); levels in all tissues decreased with increasing pH. Manganese concentration was highest in roots of E. coca and Zn concentration was highest in tissues of E. n. novogranatense. Copper, Fe, K, and Mg levels were erratic with increasing pH, indicating that sufficient amounts of these nutrients are acquired at low pH levels. Root concentrations of Fe and K in E. coca increased markedly between pH 3.5 and 4.7. At pH 3.5, E. coca demonstrated no symptoms of mineral deficiency and/or toxicity, however, chlorosis, leaf distortion and root atrophy were prevalent at pH 6.5 and 7.0. By contrast, E. n. novogranatense demonstrated diminished growth and root atrophy at soil pH 3.5, whereas at pH 6.5 and 7.0, although biomass production was reduced, no symptoms of mineral deficiency and/or toxicity were present. The species obviously behave differentially at pH extremes and E. coca appears to be most tolerant of extremely acid soils; the two species may also differ in mineral sensitivities between the species at higher pH levels. Erythroxylum coca may compete more effectively with Al for Ca binding sites within the root, and may have greater internal tolerance of Mn, compared with E. n. novogranatense.     

Bulb Formation in Onions as Affected by Photoperiod and Spectral Quality of Light

In glasshouse experiments bulb formation occurred in 5 north-temperate onion cultivars in photoperiods of 14–15 h and longer. Some response was obtained by giving 14 long days, but a greater response was obtained when the plants were kept in continuous long days. Three cultivars in the Rijnsburger group all differed from each other in the extent of their bulb development in all of several photoperiodic regimes tried, but there was no cultivar × photoperiod interaction. Thus it is possible that cultivars could usefully be compared in the glasshouse for earliness by providing any one of a wide range of photoperiodic treatments.

When grown in controlled environments with artificial light, little or no bulb formation occurred in cv. Rijnsburger with warm-white fluorescent lamps, but with de-luxe warm-white lamps it occurred when the photoperiods were 17 or more hours long. These lamps appeared to be elfective because they emitted a greater proportion of far-red light than the warm-white lamps, although not as much as sunlight. Because it is possible that the sensitivity of cultivars to the spectral composition of light may vary, it is concluded that attention should be given to this in comparative studies of the photoperiodic requirements of different cultivars.     

An Approach to the Study of Yearly and other Variation in Crop Yields

The effects of deep ploughing, shallow ploughing-with-subsoiling, shallow ploughing, and shallow rotary cultivation combined factorially with three manurial treatments on the yields of vegetable crops are described. Each of the five crops in the rotation was grown in each year from i960 to 1962 on a sandy loam at Wellesbourne.

Where a high level of fertility bad been built up by the use of farmyard manure (FYM), yields were subsequently maintained at a high level for a three-year period by the use of NPK fertilizers alone.

Plots which had received either FYM with NPK fertilizers for each crop from 1954 to 1962 (FYM -j- NPK), or FYM with NPK fertilizers from 1954 to 1959 but with NPK only from i960 to 1962 (residual FYM + NPK), gave much higher yields than plots which had received only nitrogenous fertilizers from 1954 to 1959 and NPK fertilizers from 1960 to 1962. The increases in yields from FYM + NPK over those from residual FYM + NPK were small, and significant only for autumn lettuce and leeks.

Although, on average, the differences between the yields from the three ploughing treatments were small (the largest was 10%) some of the differences were significant.

The ploughing treatments gave significantly higher yields of early peas, autumn lettuce, leeks and Brussels sprouts than shallow rotary cultivation ; with early summer cauliflowers, however, only shallow ploughing-with- subsoiling gave a higher yield than shallow rotary cultivation.     

Intraspecific diversity of Edwardsiella ictaluri isolates from diseased freshwater catfish, Pangasianodon hypophthalmus (Sauvage), cultured in the Mekong Delta, Vietnam

A molecular epidemiology study was conducted on 90 Edwardsiella ictaluri isolates recovered from diseased farmed freshwater catfish, Pangasianodon hypophthalmus, cultured in the Mekong Delta, Vietnam. Thirteen isolates of E. ictaluri derived from diseased channel catfish, Ictalurus punctatus, cultured in the USA were included for comparison. All the E. ictaluri isolates tested were found to be biochemically indistinguishable. A repetitive (rep)‐PCR using the single (GTG)₅ primer was shown to possess limited discriminatory power, yielding two similar DNA profiles categorized as (GTG)₅‐PCR group 1 or 2 among the Vietnam isolates and (GTG)₅‐PCR group 1 within the USA isolates. Macrorestriction analysis identified 14 and 22 unique pulsotypes by XbaI and SpeI, respectively, among a subset of 59 E. ictaluri isolates. Numerical analysis of the combined macrorestriction profiles revealed three main groups: a distinct cluster formed exclusively of the USA isolates, and a major and minor cluster with outliers contained the Vietnam isolates. Antibiotic susceptibility and plasmid profiling supported the existence of the three groups. The results indicate that macrorestriction analysis may be regarded as a suitable typing method among the E. ictaluri species of limited intraspecific diversity. Furthermore, the findings suggest that E. ictaluri originating from Vietnam may constitute a distinct genetic group.     

Spatial heterogeneity provides organic matter refuges for soil microbial activity in the Patagonian steppe, Argentina

In arid and semi-arid ecosystems that are frequently classified as water limited, it is unclear how spatial and temporal variability of vegetation and climate could affect microbially-mediated soil processes. Our objective was to determine how aboveground spatial heterogeneity creates characteristic soil conditions that modulate microbial growth and activity in a semi-arid Patagonian steppe. In particular, we explored how micro-environmental and biogeochemical soil characteristics generated by the native vegetation could control soil β-glucosidase activity. Both life-form (shrubs, grasses, mosses and bare soil) and season exerted strong controls on all measured abiotic (soil temperature and gravimetric soil water content, inorganic nitrogen, pH and total C and N) and biotic (microbial biomass C and β-glucosidase activity) soil characteristics. Partial correlation between β-glucosidase activity and extracellular organic C (EOC) was high across seasons (r = 0.5; P < 0.001) while soil water content did not correlate with soil enzymatic activity (r = 0.09; P > 0.05). We postulate that labile soil carbon rather than water availability functions as a principal limitation of microbial activity in this semi-arid ecosystem, and the distribution of this carbon is, in large part, determined by the patchy distribution of vegetation.