Primary lymphangiectasia in a dingo (Canis familiaris dingo).

A 3-yr-old intact male dingo (Canis familiaris dingo) presented with a 3-mo history of diarrhea. The diarrhea did not resolve with antibiotics or intestinal protectants. Fecal examination for parasites, fecal cultures, physical examination, and radiographs were unremarkable. Enteroscopic duodenal biopsies showed dilated lacteals without inflammation. Results of serum folate, cobalamin, and trypsin-like immunoreactivity were normal. Low serum total protein and albumin combined with increased fecal levels of alpha-1 protease inhibitor suggested the diagnosis of lymphangiectasia. Full-thickness intestinal biopsies of the duodenum, jejunum, and ileum revealed dilated mucosal and submucosal lacteals without associated inflammation, confirming the diagnosis of primary lymphangiectasia. Currently, the dingo is being maintained with nutritional management.     

Livestock breeding for the 21st century: the promise of the editing revolution

In recent years there has been a veritable explosion in the use of genome editors to create site-specific changes, both in vitro and in vivo, to the genomes of a multitude of species for both basic research and biotechnology. Livestock, which form a vital component of most societies, are no exception. While selective breeding has been hugely successful at enhancing some production traits, the rate of progress is often slow and is limited to variants that exist within the breeding population. Genome editing provides the potential to move traits between breeds, in a single generation, with no impact on existing productivity or to develop de novo phenotypes that tackle intractable issues such as disease. As such, genome editors provide huge potential for ongoing livestock development programs in light of increased demand and disease challenge. This review will highlight some of the more notable agricultural applications of this technology in livestock.     

Dairy farmers' attitudes and intentions towards improving dairy cow foot health

Dairy cow foot health is a subject of concern because it is considered to be the most important welfare problem in dairy farming and causes economic losses for the farmer. In order to improve dairy cow foot health it is important to take into account the attitude and intention of dairy farmers. In our study the objective was to gain insight into the attitude and intention of dairy farmers to take action to improve dairy cow foot health and determine drivers and barriers to take action, using the Theory of Planned Behavior. Five hundred Dutch dairy farmers were selected randomly and were invited by email to fill in an online questionnaire. The questionnaire included questions about respondents' intentions, attitudes, subjective norms and perceived behavioral control and was extended with questions about personal normative beliefs. With information from such a framework, solution strategies for the improvement of dairy cow foot health can be proposed. The results showed that almost 70% of the dairy farmers had an intention to take action to improve dairy cow foot health. Most important drivers seem to be the achievement of better foot health with cost-effective measures. Possible barriers to taking action were labor efficiency and a long interval between taking action and seeing an improvement in dairy cow foot health. The feed advisor and foot trimmer seemed to have most influence on intentions to take action to improve dairy cow foot health. Most farmers seemed to be satisfied with the foot health status at their farm, which probably weakens the intention for foot health improvement, especially compared to other issues which farmers experience as more urgent. Subclinical foot disorders (where cows are not visibly lame) were not valued as important with respect to animal welfare. Furthermore, 25% of the respondents did not believe cows could suffer pain. Animal welfare, especially the provision of good care for the cows, was valued as important but was not related to intention to improve dairy cow foot health. The cost-effectiveness of measures seemed to be more important. Providing more information on the effects of taking intervention measures might stimulate farmers to take action to achieve improvement in dairy cow foot health.     

Naturally occurring cyanohydrins,analogues and derivatives as potential insecticides

Several naturally occurring cyanohydrins were tested for fumigation toxicity to two insect species, the house fly (Musca domestica L) and the lesser grain borer (Rhyzopertha dominica (F)). Synthetic analogues of these compounds were tested as well. Most of the cyanohydrins tested were more toxic as fumigants to M domestica and R dominica than chloropicrin; some compounds were nearly as toxic as dichlorvos. Naturally occurring cyanohydrins were among the most toxic tested. © 2000 Society of Chemical Industry     

Accelerated methane oxidation cover system to reduce greenhouse gas emissions from MSW landfills in cold, semi-arid regions

Many regional landfills for municipal solid waste (MSW) and industrial, commercial, institutional (ICI) wastes in cold, dry regions do not produce enough gas to support conventional gas extraction, treatment, and utilization or flaring. Yet, some solution is required to reduce emissions of methane and trace constituents to the atmosphere for the protection of the public and of the global climate. Methane oxidation, as a natural biochemical process, offers an opportunity to reduce methane emissions with a simple, passive alternative cover system. The goal of this article is to develop an effective design of Methane Oxidation Covers to achieve superior methane management performance while still producing equivalent closure conditions to conventional covers in semi-arid, cold climates. specifically, the goal is to reduce methane surface emissions by 50% to 80%, with no significant increase in leachate production compared with conventional covers of clay and topsoil. A field pilot test of an alternative cover system with gas collection, methane oxidation and heat extraction was conducted on an operating MSW/ICI waste landfill in Western Canada from August 2001 to February 2005. The cool, semi-arid region experiences cold winters (down to minus 40^?C) for up to 5 months of the year, and annual precipitation rates of 150 mm to 450 mm p.a., of which one third to one half falls as snow. The need to direct gas from large surface areas to gas control zones of minimal area led to the configuration of the system of gas collection trenches connected to a central methane oxidation (MethOx) bed. The need to keep the bed above 5^?C in winter required the development of a simple, passive heat transfer system. The maintenance of suitable moisture contents and the restriction of percolation were accomplished by the choice of filter material and the layering of the bed over the gas percolation layer. The test program was conducted in three phases from August 2001 to February 2005. In the first test phase, a methane oxidation bed of yardwaste compost performed well during the summer, but froze from November to April and did not resume oxidation until May. Oxygen was always present at or above 3%(vol.) and the moisture content remained above 25%(vol.) in the lower layer of the bed. The freezing temperature caused the most serious performance reduction. In the next phases of the study, a passive heating system was installed in an accelerated methane oxidation bed. Heat exchange from inside the landfill to the filter raised the bed temperature to 14 to 18^?C during the third winter of the test. The moisture contents of 25% to 50% (v/v) in the bed were high, but the percolation rate was only 7.3 mm/a, or about 2% of total precipitation. The methane oxidation performance increased with the heating of the bed, from a 33% emission reduction in an unheated bed, up to 89% in a well heated filter bed. The achievement of high oxidation performance (over 80%), the complete reduction of surface emissions from the test area (to zero), and the low percolation rate through the filter bed (less that 2%) constitute a proof of principle for MethOx covers in cool, semi-arid climates. The possible improvement of the Alternative Cover System's performance by adding vegetation to the filter bed is currently being tested in the ongoing research project.     

Direct and indirect responses to selection on individual body weight in the Pacific oyster (Crassostrea gigas)

Three experiments were performed to examine the heritability of body weight among adult Pacific oysters (Crassostrea gigas) evaluated in Yaquina Bay, Oregon, USA, and to determine if selection on individual body weight could result in changes in offspring survival and yield. The first two experiments utilized midparent-offspring regressions to estimate the heritability (h²) of adult oyster body weight and the coheritability (h_x,y) between adult midparent body weight and offspring performance, including juvenile average body weight, survival and yield as well as adult survival and yield. In Experiment 1 both parents and offspring were evaluated in an “upriver” environment in Yaquina Bay. In Experiment 2 parents were evaluated in a “downriver” environment, while offspring were evaluated in an “upriver” environment. Experiment 3 contrasted average body weight, survival, and yield of offspring (evaluated upriver) derived from three large sires and three small sires mated to the same five females that were chosen at random (all parents evaluated downriver). In Spring 2002, 12 full-sib families from Experiment 1, 19 families from Experiment 2, and 26 families from Experiment 3 were stocked into lantern nets and suspended in Yaquina Bay. Measurements of yield (kg tier^− 1), average body weight (g), and survival (%) were recorded after one and two growing seasons in the field. Heritability estimates for adult body weight at harvest ranged from 0.313 (± 0.083) in Experiment 1 to 0.003 (± 0.073) in Experiment 2. In Experiment 3, average body weight did not differ between offspring derived from large sires and offspring derived from small sires (P = 0.47). Significant negative coheritability estimates were observed between adult midparent body weight and offspring survival in both Experiment 1 and Experiment 2. Significant negative coheritability estimates between adult midparent body weight and offspring yield were observed in Experiment 2 but not in Experiment 1. In Experiment 3, offspring derived from large sires had significantly lower survival and yield than offspring derived from small sires. These results show adult oyster body weight to be heritable but also subject to site-specific adaptation such that selection in the downriver Yaquina Bay environment was ineffective at changing average body weight in the upriver environment. Negative coheritability estimates between performance traits indicate that adult oyster body weight may be a poor indirect measure of oyster yield potential, and that selection solely for increased body weight could lead to a decrease in offspring yield.     

Estimating uncertainty in fish stock assessment and forecasting

A variety of tools are available to quantify uncertainty in age‐structured fish stock assessments and in management forecasts. These tools are based on particular choices for the underlying population dynamics model, the aspects of the assessment considered uncertain, and the approach for assessing uncertainty (Bayes, frequentist or likelihood). The current state of the art is advancing rapidly as a consequence of the availability of increased computational power, but there remains little consistency in the choices made for assessments and forecasts. This can be explained by several factors including the specifics of the species under consideration, the purpose for which the analysis is conducted and the institutional framework within which the methods are developed and used, including the availability and customary usage of software tools. Little testing of either the methods or their assumptions has yet been done. Thus, it is not possible to argue either that the methods perform well or perform poorly or that any particular conditioning choices are more appropriate in general terms than others. Despite much recent progress, fisheries science has yet to identify a means for identifying appropriate conditioning choices such that the probability distributions which are calculated for management purposes do adequately represent the probabilities of eventual real outcomes. Therefore, we conclude that increased focus should be placed on testing and carefully examining the choices made when conducting these analyses, and that more attention must be given to examining the sensitivity to alternative assumptions and model structures. Provision of advice concerning uncertainty in stock assessments should include consideration of such sensitivities, and should use model‐averaging methods, decision tables or management procedure simulations in cases where advice is strongly sensitive to model assumptions.     

A comparison of multispectral aerial and satellite imagery for mapping intertidal seaweed communities

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