A genealogical survey of Australian registered dog breeds

Breeding practices were analysed for 32 registered dog breeds representing very small registries (120 Central Asian shepherd dogs) through to very large registries (252,521 German shepherd dogs) in Australia. The vast majority (91%) of registered kennels in Australia that were sampled did not regularly employ either close breeding or popular sire usage in their kennels and the weighted mean inbreeding coefficient of Australian pedigree dogs was <5%. Australian breed mean inbreeding coefficients ranged from 0% (Central Asian shepherd dog) to 10.1% (Bichon Frise). Breed effective population sizes ranged from 26 (Ibizan hound) to 1090 (Golden retriever), comparable with other species of domesticated animals. The relatively low levels of inbreeding suggest that pedigree dog disorders are unlikely to arise frequently from the use of popular sires or close breeding in Australian registered dog breeds. It is possible that deleterious allele fixation might be driven by founder effects, genetic drift or adverse selection practices, which were not assessed in this analysis. European popular sire definitions should be revisited for rare breeds.     

Establishment of a standard operating procedure for predicting the time of calving in cattle

Precise calving monitoring is essential for minimizing the effects of dystocia in cows and calves. We conducted two studies in healthy cows that compared seven clinical signs (broad pelvic ligaments relaxation, vaginal secretion, udder hyperplasia, udder edema, teat filling, tail relaxation, and vulva edema) alone and in combination in order to predict the time of parturition. The relaxation of the broad pelvic ligaments combined with teat filling gave the best values for predicting either calving or no calving within 12 h. For the proposed parturition score (PS), a threshold of 4 PS points was identified below which calving within the next 12 h could be ruled out with a probability of 99.3% in cows (95.5% in heifers). Above this threshold, intermitted calving monitoring every 3 h and a progesterone rapid blood test (PRBT) would be recommended. By combining the PS and PRBT (if PS ≥ 4), the prediction of calving within the next 12 h improved from 14.9% to 53.1%, and the probability of ruling out calving was 96.8%. The PRBT was compared to the results of an enzyme immunoassay (sensitivity, 90.2%; specificity, 74.9%). The standard operating procedure developed in this study that combines the PS and PRBT will enable veterinarians to rule out or predict calving within a 12 h period in cows with high accuracy under field conditions.     

Spiroplasma found in the eyes of scrapie affected sheep

Objective Scrapie, a transmissible spongiform encephalopathy (TSE) occurring naturally in sheep, characteristically shows a severe retinopathy that is well developed in the terminal phases of the disease. In this study, we set out to demonstrate similar retinal changes in our ruminant spiroplasmosis TSE model. Procedure The eyes from deer, sheep, and goats that were inoculated intracranially with the laboratory strain of spiroplasma (suckling mouse cataract [SMCA] strain of Spiroplasma mirum) or with Spiroplasma sp. isolated from the brains affected with scrapie or with chronic wasting disease were examined by light microscopy for pathologic changes and by immunocytochemistry for distribution of spiroplasma antigen. The eyes were also obtained from a research flock of sheep with terminal scrapie, from which the intraocular tissues were submitted aseptically for culture assay in M1D broth or as explants on bovine corneal endothelia (BCE). Results The eyes from the spiroplasmosis ruminant models showed retinopathy remarkably similar to eye lesions seen in sheep with scrapie. The spiroplasma antigen accrued in the ruminant model eye tissues, particularly in the retina, the vitreous humor, and the corneal endothelia. A Spiroplasma sp. grew out of the scrapie‐affected eyes both in the M1D broth and in the BCE cultures but did not expand. These new spiroplasma isolates differed immunologically from SMCA. Conclusion These data showed a clear association of spiroplasma with scrapie suggesting that these bacteria have a role in the pathogenesis of TSE and that the eye should be a research focus for future studies of TSE.     

Epidemics of ray blight on pyrethrum are linked to seed contamination and overwintering inoculum of Phoma ligulicola var. inoxydabilis

Ray blight, caused by Phoma ligulicola var. inoxydabilis, is the most damaging disease of pyrethrum (Tanacetum cinerariifolium) in Australia. Data collected from 72 plots in commercial pyrethrum fields since 2001 to 2009 revealed substantial annual variations in isolation frequency of the pathogen during semidormancy of the crop in autumn and winter. Isolation frequency of the pathogen during this time and subsequent outbreaks of ray blight in spring were similar across the eight production regions where sampling was conducted, and isolation frequency of the pathogen was linearly correlated (r = 0.88; P < 0.0001) with subsequent defoliation severity when plants commenced growth in spring. Isolation frequency and defoliation severity also were correlated with the incidence of seed infested with P. ligulicola var. inoxydabilis (r = 0.71 and 0.44, respectively; P < 0.0001 in both correlations). Highly accurate risk algorithms for the occurrence of severe epidemics of ray blight were constructed using logistic regression. A model based solely on isolation frequency of the pathogen over autumn and winter correctly predicted epidemic development in 92% of fields. Another model utilizing the incidence of infested seed and rain-temperature interactions in early autumn (austral March and April) and late winter (austral June and July) had similar predictive ability (92% accuracy). Path analysis modeling was used to disentangle interrelationships among the explanatory variables used in the second logistic regression model. The analysis indicated that seedborne inoculum of P. ligulicola var. inoxydabilis contributes indirectly to ray blight defoliation severity through directly increasing overwintering frequency of the pathogen. Autumn and fall weather variables were modeled to have indirect effects on defoliation severity through increasing overwintering success of the pathogen but also direct effects on defoliation severity. Collectively, the analyses point to several critical stages in the disease cycle that can be targeted to minimize the probability of regional epidemics of ray blight in this perennial pathosystem.     

The importance of chemical communication studies to mammalian conservation biology: A review

The relevance of chemical communication to mammalian conservation is not often the focus of scientific investigation. Our review identifies and discusses ten key areas in which the study of chemical communication aids conservation behaviour. Articles (n = 140) were revealed, most were concerned with population monitoring (22.50%), reducing human-wildlife conflicts (18.93), influencing habitat selection (18.57%), increasing welfare of captive animals (12.86%), encouraging captive breeding (12.86%), reducing predation (5.71%), and increasing the success of release programmes (5.00%). Few articles (<4%) were found relating olfactory studies to health status of wild populations, reducing hybridization or as indication of pollution. A growing number of articles are addressing how olfactory studies may aid conservation, but more rigorous experimental testing and manipulations are required. The vast majority of studies linking olfaction with conservation involved the population monitoring of wild carnivores. We suggest that animal behavioural studies and manipulations of chemical communication can have significant impacts on conservation in these areas, which should be further developed to generate practical applications. Areas of future study include chemical communication of aquatic mammalian species, the transfer of olfactory cues under water, and the identification of genetic markers that may link ‘personality’ with olfactory responses. Linking olfactory studies to fitness, either on an individual or population scale, particularly in a wider ecological context is more likely to increase conservation value. Animal translocations and reintroduction programmes may offer a means to do this and could be an important area to direct future studies.     

Within crown variation in the relationship between foliage biomass and sapwood area in jack pine

The relationship between sapwood area and foliage biomass is the basis for a lot of research on eco-phyisology. In this paper, foliage biomass change between two consecutive whorls is studied, using different variations in the pipe model theory. Linear and non-linear mixed-effect models relating foliage differences to sapwood area increments were tested to take into account whorl location, with the best fit statistics supporting the non-linear formulation. The estimated value of the exponent is 0.5130, which is significantly different from 1, the expected value given by the pipe model theory. When applied to crown stem sapwood taper, the model indicates that foliage biomass distribution influences the foliage biomass to sapwood area at crown base ratio. This result is interpreted as being the consequence of differences in the turnover rates of sapwood and foliage. More importantly, the model explains previously reported trends in jack pine sapwood area at crown base to tree foliage biomass ratio.     

Practicable group testing method to evaluate weight/weight GMO content in maize grains

Because of the increasing use of maize hybrids with genetically modified (GM) stacked events, the established and commonly used bulk sample methods for PCR quantification of GM maize in non-GM maize are prone to overestimate the GM organism (GMO) content, compared to the actual weight/weight percentage of GM maize in the grain sample. As an alternative method, we designed and assessed a group testing strategy in which the GMO content is statistically evaluated based on qualitative analyses of multiple small pools, consisting of 20 maize kernels each. This approach enables the GMO content evaluation on a weight/weight basis, irrespective of the presence of stacked-event kernels. To enhance the method's user-friendliness in routine application, we devised an easy-to-use PCR-based qualitative analytical method comprising a sample preparation step in which 20 maize kernels are ground in a lysis buffer and a subsequent PCR assay in which the lysate is directly used as a DNA template. This method was validated in a multilaboratory collaborative trial.     

Smooth Brome (Bromus inermis Leyss) and Soil Chemical Response to Concrete Grinding Residue Application

Concrete grinding residue (CGR) is a by-product created by concrete pavement maintenance operations. The application of CGR to roadside soils is not consistently regulated by state agencies across the USA, which is partially due to the lack of science-based information on its impacts to soils and plants. The objectives of this research were to determine the impact of CGR additions to soil on both smooth brome (Bromus inermis L.) biomass and plant and soil chemical parameters. In a greenhouse study, two soils were treated with two CGR by-products at 8% and 25% by weight. Shoot biomass was significantly influenced by the main effects (Soil, CGR, and Rate) and by all two-way interactions, but not consistently positively or negatively correlated. Trace metal concentrations in the shoot biomass were variable, but 68% of these metals had the same concentration or lower in the 25% CGR treatments compared with the controls. Soil pH and electrical conductivity were significantly influenced by the main effects and two-way interactions of Soil × Rate and CGR × Rate, and soil pH was significantly greater in the CGR-treated soils. Calcium, Na, Mg, Al, and S concentrations in soils were all influenced by additions of CGR, but trace metal levels in the treatments were all within the range for uncontaminated soils. Ecosystem impact of applying CGR will be dependent upon the quality of CGR and soil characteristics. Controlling the liming potential of CGR should be considered a best management practice.     

Multielement isotope analysis of bovine muscle for determination of international geographical origin of meat

Multielemental (C, N, H, S) stable isotope ratio analysis was used as an analytical tool to verify the geographical origin of beef from several European and non-European countries. Beef samples were collected from nine different countries, and the (13)C/(12)C, (15)N/(14)N, (2)H/(1)H, and (34)S/(32)S ratios of defatted beef were measured using isotope ratio mass spectrometry (IRMS). There were highly significant differences in the mean isotopic values of the beef from different countries. The results of discriminant analysis showed that the four isotope ratios were significant for the discrimination of geographical origin and that 84.9% of the samples were correctly assigned to the country of origin (82.2% when cross-validated). Beef was also classified according to geographical origin when additional information on different feeding regimens used in Ireland was included, with 85.0% of the samples correctly allocated and 82.9% cross-validated using the isotopic signatures. All of the Irish beef samples verifiable as pasture-fed beef were correctly classified and then cross-validated.     

Effects of Medicago sativa, Taraxacum officinale and Bromus sterilis on the density and diversity of Collembola in grassy arable fallows of different ages

The density and diversity of Collembola of nine grassy arable fallows of different ages were investigated in a factorial design with the factors ‘plant species’ (legume: Medicago sativa, herb: Taraxacum officinale, grass: Bromus sterilis) and ‘age class’ (2-3, 6-8 and 12-15 years) including the random effect ‘site’ (1-9). In May 2008, four plots were selected randomly at each fallow. Within each plot five M. sativa, T. officinale and B. sterilis plants were extracted with their associated soil using steel cylinders. The material from each plant species was used for extraction of Collembola and for determination of environmental parameters. Thus, the new aspect of the present study compared to other field studies investigating the relationships between plant and Collembolan communities is the focus on the “micro-scale”, investigating the Collembolan communities of the soil associated with single plants.We found that species richness and density of total and euedaphic Collembola were significantly higher in B. sterilis than in T. officinale samples with the M. sativa samples being intermediate. Fine-root feeding euedaphic Collembola particularly benefited from the higher amount of fine roots in B. sterilis samples. We also discovered that the age of the fallows had no significant influence on the number of Collembolan species and the density of the Collembolan groups. Notably, however, species of the epedaphic genera Lepidocyrtus and Sminthurinus were associated with the 12-15 year-old fallows and presumably benefited from the high number of plant species in the old fallows. Finally, canonical correspondence analysis (CCA) indicated that the soil organic matter content and the microbial biomass, both potential food sources for many Collembolan species, were important structuring forces for the Collembolan communities.