Behavior and endocrine changes in high-performing, low-performing, and male-oriented domestic rams following exposure to rams and ewes in estrus when copulation is precluded.

High-performing, low-performing, and male-oriented rams were used to investigate behavior and neuroendocrine correlates of sexual interest and discrimination. Treatment consisted of visual and olfactory contact with stimulus animals through a woven wire fence, which inhibited copulation (either ewes in estrus or other rams), for 4 h on each of three consecutive days. Before exposure to stimulus animals on d 1 and during the final 1 h of exposure on d 2, blood samples were collected every 15 min for 1 h to determine concentrations of LH and testosterone. During exposure to stimulus animals, rams were continuously observed and investigatory behaviors were recorded. There was no day effect for any behavior. Groups of rams differed (P < .05) in amounts of behaviors exhibited, but behaviors were not influenced by sex of stimulus animals. High-performing rams exhibited more (P < .05) investigatory behaviors toward stimulus animals than low-performing or male-oriented rams. Plasma concentrations of LH increased (P < .05) in high-performing rams following exposure to estrous ewes, but not following exposure to rams. In low-performing and male-orientated rams, concentrations of LH were unchanged regardless of sex of the stimulus animal. Change in plasma concentrations of testosterone from pre- to posttreatment did not differ between high-performing, low-performing, and male-oriented rams. However, low-performing rams exhibited an increase (P < .05) in plasma concentrations of testosterone following exposure to rams. In conclusion, high-performing rams exhibit a high degree of investigatory behaviors toward estrous ewes and other rams. High-performing rams seem to discriminate sex of stimulus animals and exhibit a neuroendocrine response (i.e., increased plasma LH) only when exposed to ewes in estrus. The sensory signals provided by estrous females are either not detected by low-performing or male-oriented rams or are not sufficiently provocative to elicit further investigation by these rams.     

Factors in the Success and Failure of Microbial Insecticides in Forestry

The minor position of microbial insecticides within the global pesticide market can be attributed to a number of causes, including high cost of production, high specificity, poor application technology, poor persistence and slow speed of kill. These aspects are discussed in relation to the potential for use of microbial insecticides against forest pests. Many of the constraints are not limiting in forestry and some of the ways in which they can be overcome are discussed, including the concept of a better appreciation of the ecological context. This approach encompasses knowledge of the behaviour of the target host species, both for improved targeting and for maximum exploitation of secondary inoculum. These, and other aspects are brought together in discussing the future for microbial insecticides in forest pest management.     

Chalky and Translucent Rice Grains Differ in Starch Composition and Structure and Cooking Properties

Chalk is an important quality characteristic in rice and occurs most commonly when high temperatures are experienced during grain development. The aims of this report are to determine whether chalk affects cooking quality and to attempt to explain the effects on the basis of starch and protein in chalky and translucent grains. Three cultivars of rice were grown in the glasshouse at either 38/21°C or 26/15°C (day/night temperatures). Rice grown at the higher temperature contained more chalky grains. Grains in the inferior position were more susceptible to forming chalk than were those in the superior position. The presence or absence of chalk affected cooking quality but neither amylose content, amylopectin structure nor protein composition explained the differences in cooking quality. However, the shape, size, and packing of amyloplasts and cells in chalky grains differed from those in translucent grains and might offer an explanation for the differences in cooking quality. It seems likely that the processes involved in the initiation or packing of amyloplasts are susceptible to high temperatures.     

Changes in the distributions of freshwater mussels (Unionoida: Hyriidae) in coastal south‐eastern Australia and implications for their conservation status

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Extinction debt or habitat change? - Ongoing losses of woodland birds in north-eastern New South Wales, Australia

The loss, fragmentation and degradation of native vegetation are major causes of loss of biodiversity globally. Extinction debt is the term used to describe the ongoing loss of species from fragmented landscapes long after the original loss and fragmentation of habitat. However, losses may also result from habitat changes that are unrelated to fragmentation, which reduce breeding success and recruitment. Many woodland birds have declined in fragmented landscapes in Australia, probably due to loss of small, isolated populations, though the ecological processes are poorly understood. We record the progressive regional loss of two ground-foraging, woodland birds, the Brown Treecreeper Climacteris picumnus and Hooded Robin Melanodryas cucullata, in northern New South Wales, over 30 years. This has happened despite most habitat loss occurring over 100 years ago, suggesting the payment of an extinction debt. Our observations suggest that several ecological processes, caused by habitat loss, fragmentation or degradation, and operating over different time scales, have led to both species’ declines. Female Brown Treecreepers disperse poorly among vegetation remnants, leaving only males in isolated populations, which then go extinct. In contrast, Hooded Robins suffer high nest predation in fragmented landscapes, producing too few recruits to replace adult mortality. Foraging by both species may also be affected by regrowth of ground vegetation and shrubs. We found little support for a major role played by drought, climate change or aggressive Noisy Miners Manorina melanocephala. We propose that both extinction debt in the classical sense and ongoing habitat change frequently contribute to species’ decline in modified landscapes. Management to arrest and reverse such declines needs to consider these multiple causes of decline. For instance, reconnecting isolated populations may be inadequate alone, and activities such as appropriate grazing, fires and the addition of woody debris may also be required.     

High-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium isolated from a wound in a dog

This report describes the first clinical case, in Europe, of a high-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium infection in a dog. The aim of this report is to alert the veterinary profession to high-level gentamicin-resistant and vancomycin-resistant Enterococcus faecium in companion animal patients. Multi-drug resistant strains of this pathogen are the cause of considerable problems in human hospitals and for community healthcare professionals worldwide. The potential for a similar impact within veterinary medicine is discussed.     

Prediction of human cases of West Nile virus by equine cases, Saskatchewan, Canada, 2003

In 2003, an outbreak of West Nile virus (WNV) occurred in Saskatchewan, Canada from July to September. One-hundred thirty-three horse cases and 947 human cases were recorded and data were analyzed retrospectively for evidence of clustering to determine if clinical infection in the horse population could be used to estimate human risk of infection with WNV. Kulldorff's scan statistic was used to identify spatial-temporal clusters in both the human and horse cases. In most areas, human clusters were not preceded by horse clusters. In one area, a significant cluster of horse cases preceded human cases by 1 week; however, 1 week does not provide sufficient time for human-health authorities to act and provide advance warning for the public.     

Cerebrospinal fluid from a 6-year-old dog with severe neck pain

A 6-year-old, intact female, Labrador Retriever/Terrier cross was presented to the University Veterinary Hospital, University College Dublin with a 3-week history of therapy-resistant cervical pain and intermittent fever. Physical examination findings included marked cervical pain resulting in neck extension and vocalization. Examination of the CSF revealed mild pleocytosis (total nucleated cells = 0.009 x 10(9)/L, reference interval <0.005 x 10(9)/L). Cytocentrifuged preparations of the CSF were of low cellularity, containing predominantly macrophages and occasional small lymphocytes. Several small- to medium-sized fragments of a slightly granular, amorphous, eosinophilic substance were observed. The majority of mononuclear cells were located within this material, in small groups of 3-13 cells. The amorphous foamy material stained positive with Luxol fast blue, suggestive of myelin-like material. The dog was euthanized and postmortem examination revealed intervertebral disk protrusion between C2 and C3. Hematoxylin- and Luxol fast blue-stained histopathologic sections of brain and spinal cord revealed only mild hemorrhage. The extracellular material in the CSF of this dog may have been caused by myelin degeneration or leakage of phospholipids from damaged cells. Because no histologic evidence of demyelination was observed with the disk extrusion, the myelin-like material in this case was thought to be the product of phospholipid breakdown from damaged cellular membranes. Three cases of dogs with spinal cord disease and myelin-like material in the CSF have been reported previously. The clinical significance of this finding is still unknown.     

Carbon banking: Creating flexibility for forest owners

The focus of forest-based systems for sequestering carbon has largely been on creating permanent stores of carbon on defined areas of land with a single payment to the forest owner for the carbon. In terms of forest management, this focus leads to two outcomes, continuing production of timber if the forest area is sufficiently large to create an effective permanent carbon pool, or a cessation of harvesting if the forest area is too small. In addition, the payment system for carbon is generally based on matching a specific buyer and seller of carbon using a single payment to the forest owner. In combination, both of these factors create a carbon sequestration system that is too inflexible to attract anything but the largest land or forest owners. The paper presents an alternative system for carbon sequestration, carbon banking. Carbon banking treats sequestered carbon in the same way that a financial institution treats capital. In essence, forest owners ‘deposit’ carbon, in exchange for an annual payment, and those who need carbon offsets ‘borrow’ carbon by making an annual payment. The role of the carbon bank is to aggregate deposits of carbon and use these to meet various demands for carbon. There are a number of benefits of this system. It provides an opportunity for small forest owners with different types, age classes and management strategies to participate in carbon markets because payments are based on current carbon sequestered. It also allows participants in the carbon market to receive current value for carbon rather than what effectively represents the capitalised value of the future benefits of sequestering carbon, thus removing some uncertainty about locking into the wrong value for carbon.     

Breaking new ground in food regime theory: corporate environmentalism,ecological feedbacks and the ‘food from somewhere’ regime?

Early food regimes literature tended to concentrate on the global scale analysis of implicitly negative trends in global food relations. In recent years, early food regimes authors like Harriet Friedmann and Philip McMichael have begun to consider the sites of resistance, difference and opportunity that have been emerging around, and into contestation with, new food regime relations. This paper examines the emerging global-scale governance mechanism of environmental food auditing—particularly those being promoted by supermarkets and other large food retailers—as an important new dynamic in our understanding of the politics and potentials of food regimes. Commencing with an examination of Friedmann’s corporate environmental food regime, two key dynamics are identified as being pivotal in the rise and decline of global-scale regimes: securing social legitimacy for food relations and the importance of ecological dynamics in global food relations. By extending McMichael’s notion of ‘Food from Nowhere’ versus ‘Food from Somewhere’, the paper interrogates the emergence of a cluster of relations that comprise ‘Food from Somewhere’ and examines whether this cluster of relations has the potential to change some of the constituent ecological dynamics of food regimes. These ecological dynamics have historically been problematic, amply demonstrating Marx’s metabolic rift as the early food regimes solidified relationships between ‘ecologies at a distance’. By using socio-ecological resilience theory, ‘Food from Somewhere’ is characterized as having denser ecological feedbacks and a more complex information flow in comparison to the invisibility and distanciation characterizing earlier regimes as well as contemporary ‘Food from Nowhere’. The conclusion of this article is that while ‘Food from Somewhere’ does provide one site of opportunity for changing some key food relations and ecologies, the social legitimacy of this new form of food relations does rely on the ongoing existence of the opposite, more regressive, pole of world food relations. The key question for resolving this tension appears to be whether new food relations can open up spaces for future, more ecologically connected, global-scale food relations.