Microsatellite pedigree analysis reveals high variance in reproductive success and reduced genetic diversity in hatchery-spawned northern abalone

The northern (or pinto) abalone, Haliotis kamtschatkana, is a broadcast-spawning marine gastropod that was recently listed as endangered in Canada. To aid in species recovery, a captive-breeding and supplementation program is underway in Barkley Sound, British Columbia. We genotyped first generation progeny for five microsatellite loci and used a pedigree reconstruction program (Pedigree 2.2) to identify their genealogical relationships in the absence of information on parental genotypes. We analyzed progeny from three separate group-spawning events and inferred considerable variation in the number of offspring produced by each parent; in the most severe case a single male sired all the progeny produced during one spawning event. After only one generation of captive-breeding we found a 55–60% reduction in allelic richness and a 17–18% reduction in heterozygosity relative to the diverse wild source population. This study illustrates the difficulty of managing genetic diversity in hatchery populations of a broadcast-spawning species, even when gametes are collected separately from each individual broodstock.     

Pest survey of softwood boxes,with special emphasis on pinewood nematode,Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae)

Wood packaging material (WPM) is an important pathway for the spread of non‐native plant pests. To reduce the likelihood of plant pest movement with WPM, the International Standard for Phytosanitary Measures No. 15: “Regulation of Wood Packaging Material in International Trade” (ISPM 15) was developed in the framework of the International Plant Protection Convention. To be compliant with this Standard, WPM shipped internationally must be either heat‐treated or fumigated, regardless of any specific characteristics of the WPM. The objective of this survey was to determine if Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) or insects, especially Monochamus spp. (Coleoptera: Cerambycidae), were present in a specific subset of softwood boxes. While not compliant with ISPM 15, these boxes had been treated with wood preservatives, stored indoors for over five years, and, in addition to meeting various quality standards, almost all had a moisture content below 20 percent. United States Department of Agriculture staff inspected a sample of 630 softwood boxes, focusing on those showing signs of possible pest infestation. Based on a binomial distribution with an efficacy of detection equal to 0.95, a sample size of 630 provides a 95 percent confidence of detecting pests if >0.5 % of boxes are infested. No B. xylophilus or insect pests were found in the boxes, though other nematode genera (Aphelenchoides, Aphelenchus, and Filenchus), which feed on decomposing fungi in wood and do not damage trees, were found in 21 boxes. This study demonstrates that not all types of WPM present a high phytosanitary risk. It may be worthwhile to consider an amendment to ISPM 15 to differentiate between various risk categories of WPM in order to minimize costs and environmental impacts associated with treatments currently prescribed in ISPM 15.     

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.     

Three cases of canine leptospirosis in Quebec

Three dogs from different locations with acute renal failure were hospitalized in autumn 1996 and 1997. Leptospira interrogans serovar pomona was detected by the microscopic agglutination test. All dogs recovered after antibiotic treatment. The importance of the development of vaccines adapted to emerging serovars in dogs should be addressed.     

Water intake and wastage at nipple drinkers by growing-finishing pigs

Three experiments were conducted to assess water intake, water wastage, and a means to decrease water wastage by growing-finishing pigs from nipple drinkers. In Exp. 1, 48 pigs were studied during two periods (average BW = 53 and 72 kg for Period 1 and 2, respectively). Water disappearance and wastage were determined for 4 d, while nipple drinkers were set at 50 mm above the shoulder height of the smallest pig in the pen (recommended heights), with flow rates at 700 mL/min during Period 1, and 1,000 mL/min during Period 2. Water intake rate was assessed at two nipple flow rates, approximately 650 and 1,300 mL/min during the Period 1, and 1,000 and 2,000 mL/min during the Period 2. The average water intake was 4.01 and 5.38 +/- 0.19 L.pig(-1).d(-1) during Periods 1 and 2, respectively (P < 0.01). Water wastage as a percentage of water disappearance was similar between the two periods (25.8 and 27.0 +/- 1.9% for Periods 1 and 2, respectively). Water intake rate was 467 and 795 mL/min (+/-34.2; P < 0.01) during Period 1, and 722 and 1,422 mL/min (+/-80.0; P < 0.01) during Period 2, at the lower and higher flow rates, respectively. In Exp. 2, 32 pigs were used in a 2 x 2 factorial design to determine effects of nipple heights (recommended vs. unadjusted = 330 mm) and flow rates (500 vs. 1,000 mL/min) on water intake and wastage. Water wastage was increased (P < 0.01) on the unadjusted vs. recommended nipple height, and the higher flow rate also resulted in greater wastage (P = 0.03) compared with the lower rate. In Exp. 3, water disappearance and manure output in 16 pens of 18 pigs per pen were monitored for 12 wk (average initial BW = 32 kg) using four drinker treatments (bowl drinker, nipple drinker at recommended heights, an unadjusted nipple set at 480 mm, and high nipple drinker height of 730 mm with a step underneath). For pigs on the high nipple drinker, the average water disappearance and manure output did not differ from those of the pigs on the recommended nipple heights and bowl drinker, but these measurements were 15 and 12% lower, respectively, than for the pigs on the low nipple drinker. The results indicate that growing-finishing pigs can maintain adequate water intake from a variety of drinker types and management. Water wastage can be controlled through drinker management.     

A methodological approach for ecotoxicological characterization of non-hazardous sediments for their beneficial reuse

Purpose

In France, the beneficial reuse of sediments is conditioned upon a demonstration of environmental acceptability for each scenario. Such evidence has to be provided in application of the NF EN 12920 +A1 standard methodologies. Before the application of risk assessment methodology, the HP14 hazard property must be measured using specific bioassays. However, sediments may have ecotoxicological impacts despite a non-hazardous classification. The application of a battery of bioassays sensitive to non-hazardous sediments could allow to select sediments before choosing the beneficial reuse option.

Materials and methods

First, HP14 methodologies were applied on the studied sediments. These sediments had to be managed on shore according to French legislation. Then, following recommendations from a previous study, other ecotoxicological tests and modified ecotoxicological tests from HP14 methodology were selected. Ostracods mortality and growth tests were selected as a complement because its sensitivity to sediment ecotoxicity is known. To take into account the effects of extraction method and liquid/solid ratio on ecotoxicological impact of sediments, ecotoxicological tests have been applied to percolates. They have been obtained from up-flow percolation tests following the standard NF EN 14405. For each percolate, the rotifer clones reproduction test and the ostracod mortality and growth tests were performed.

Results and discussion

Contaminant analyses of sediments studied reveal differences in contamination between non-hazardous sediments. The majority of ecotoxicological tests carried out in the HP14 test batteries do not differentiate between non-hazardous sediments with low ecotoxicity. However, inhibition of rotifer reproduction and inhibition of plant germination and growth tests can be used. Among the complementary bioassays performed, the ostracods growth inhibition and multigenerational Daphnia reproduction inhibition tests are especially sensitive. Bioassays performed on percolates reveal low ecotoxicities that were not detected with conventional bioassays. For these tests, maximum ecotoxicities are observed on the first percolates for most of the tested sediments, and ecotoxicity effects decrease with the increase in the liquid/solid ratio.

Conclusions

The results enable us to propose a bioassay battery able to highlight the intrinsic toxicity of non-hazardous sediments. This is achieved through bioassays and using up-flow percolation columns to detect low ecotoxicity. This battery can be integrated into the SEDIMATERIAUX approach to ensure the choice of the beneficial reuse option for such sediment. As some of the proposed bioassays remain unsuitable for marine sediments, future studies will adapt the methodology to the presence of marine salts.

     

Stock quality assessment through an integrated approach

Forest regeneration can be improved by matching seedling stock with reforestation site environmental conditions. To achieve this improvement, one must characterize seedling performance potential with anticipated field site conditions. A theoretical performance potential index (PPI) has been developed to forecast seedling field performance during the first growing season on a reforestation site. PPI includes material and performance attribute tests that characterize seedling performance potential under optimum and limiting environmental conditions. Test results are standardized and then integrated resulting in a comprehensive assessment procedure. The PPI concept is demonstrated using containerized western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings subjected to a series of dormancy induction treatments and the results are compared with actual seedling performance during the first growing season on a reforestation site. Results indicated that PPI values for western hemlock seedlings treated with various dormancy induction treatments corresponded to field performance. Possible use of PPI in stock selection is discussed.     

Vegetative propagation of two endemic species of <Emphasis Type="Italic">Cloezia</Emphasis> Brongn. &; Gris for conservation and mining revegetation activities in New Caledonia

A study to determine the best vegetative propagation protocol was carried out for two species of the endemic genus Cloezia for conservation and mining revegetation activities in New Caledonia. Effects of clonal capacities and auxin treatments on rooting of C. buxifolia and C. aquarum semi-hardwood cuttings taken from wild populations were evaluated in four experiments. Different phenotypes varied in their capacity to root (from 0 to more than 80%) and this underlines the importance of collecting cuttings from different plants when revegetation programs are based on vegetative propagation. The experiments evaluated the effectiveness of IBA at 5, 10 and 20 g kg⁻¹, IAA at 5 and 10 g kg⁻¹ and NAA at 1 and 2 g kg⁻¹ treatments to enhance rooting of C. buxifolia tip cuttings and C. aquarum tip and stem cuttings compared to control cuttings with no applied auxin. With the exception of IAA, auxin treatments enhanced the percentage of cuttings with roots and significantly improved the number of roots per cutting and root length. In this study, the best treatment is 10 g kg⁻¹ IBA for C. buxifolia. For C. aquarum, 20 g kg⁻¹ IBA significantly enhances quantitatively and qualitatively rooting of both tip and stem cuttings.

---

Résumé  Cette étude porte sur la définition d’un protocole de multiplication végétative optimale de deux espèces du genre endémique Cloezia dans un but de conservation et de revégétalisation en Nouvelle-Calédonie. Quatre essais visent à déterminer les potentialités clonales de différents individus et l’effet de divers traitements hormonaux sur l’enracinement de boutures de C. buxifolia et C. aquarum. L’enracinement des boutures dépend du pied-mère sur lesquelles elles sont récoltées et peut varier de 0 à plus de 80%, ce qui indique l’intérêt de la méthode d’échantillonnage lors de la collecte des boutures. L’effet de traitements hormonaux à base d’AIB, AIA et ANA à différentes concentrations, respectivement de 5, 10 et 20 g kg⁻¹, 5 et 10 g kg⁻¹ et 1 et 2 g kg⁻¹ est également étudié sur des boutures de tête de C. buxifolia et des boutures de tête et de tige de C. aquarum. Ces traitements améliorent le pourcentage d’enracinement et augmentent significativement le nombre de racines produites et la longueur des racines des boutures de Cloezia, à l’exception des traitements à base d’AIA. Dans cette étude, le meilleur traitement est 10 g kg⁻¹ d’AIB pour C. buxifolia et 20 g kg⁻¹ d’AIB pour C. aquarum.

     

Hydrogen sulfide assessment in shallow-pit swine housing and outside manure storage

In Saskatchewan, some recent incidents have lead us to believe that certain manure management activities can potentially release high concentrations of H2S into the atmosphere of shallow-pit barns. The objectives of the monitoring project reported here were to evaluate worker exposure to H2S during the completion of the following tasks: emptying of in-barn shallow manure pits, power washing of barn rooms, and agitation and emptying of outdoor manure storage facilities. In-barn monitoring was performed in gestation, farrowing, nursery, and grow-finish sections in the summer of 2001 and the winter of 2002 on four different farms. Plug pulling can generate very high concentrations of H2S. The maximum values recorded during some of the monitored events reached 1,000 ppm. The H2S released as a plug is being pulled does not follow a predictable pattern when considering the level that will be reached, the concentration variations during the event, and the time at which the peak concentration will be observed. Power washing generated lower H2S concentrations than plug pulling. However, as the task to be performed generally takes time, the 15 min time-weighed average of 15 ppm (STEL) can be reached after the task started and can be exceeded for a long period of time, which for some of the monitored events was more than 30 min. Finally, monitoring at the storage facilities showed that the risks of exposure to excessive H2S concentrations during the agitation and emptying of outside manure storage facilities were very limited. Results from this study suggest that pig production buildings involving short-term storage of liquid manure may present H2S exposure risks that have been underestimated until now. All workers should be provided with an H2S monitor and safety equipment to ensure that workers are protected when the H2S concentration rises. As well, engineering controls have to be developed to prevent H2S formation in the manure or H2S emission into the worker/pig space.