Effect of water-spray cooling treatment in a Douglas-fir seed orchard on seed germination

Overhead-cooling treatment used to delay flowering produced non-significant effects on germination capacity, germination rate, germination value, and abnormal germination of seeds from a 13-year-old Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] seedling seed orchard. The percentage of variation accounted for by cooling treatment ranged from 0.0 to 1.0%. In contrast, variation among trees within treatments ranged from 28 to 46%. These effects were significant, indicating that each tree has an individual germination pattern. The temporal delay of reproductive phenology caused by temperature manipulation as a result of the cooling treatment was judged to be within the species' biological limits.     

Biochemical composition of loblolly pine reflects pollutant exposure

Under experimental conditions, the growth of loblolly pine (Pinus taeda L.) is often responsive to ozone at near-ambient concentrations. However, little is known of the biochemical changes associated with this or other pollutants. Loblolly pine seedlings in open-top chambers were exposed to combinations of ozone (sub-ambient, ambient, or twice-ambient), acidic precipitation (pH 3.8 or pH 5.2) and soil magnesium (0.15 or 0.32 microg g(-1) exchangeable Mg) for three growing seasons. The effects of these treatments were greater in foliage than in stems or roots. The largest treatment effect was a 50% decrease in the starch concentration of current-year foliage from the twice-ambient ozone treatment compared with current-year foliage from the sub-ambient ozone treatment. Responses to ozone were consistent with the hypothesis that ozone-induced growth reductions are associated with depletion of carbohydrate reserves resulting from injury compensation and repair processes or reduced carbon fixation or both. Addition of acidic precipitation, and to a small extent Mg, decreased sugar concentrations of tissues; however, this effect appeared to be mediated by nutrient addition rather than by acidity per se. Given the role of carbohydrates in plant resistance to environmental stress, the sensitivity of carbohydrates to experimental treatments demonstrates the potential for indirect effects of ozone, acidic precipitation, and soil properties on stress resistance. Noncarbohydrate constituents were largely unresponsive to the experimental treatments. These findings imply that tissue carbohydrate analysis may be useful for assessing the impacts of pollutants in forest ecosystems.     

Growth efficiency increases as relative growth rate increases in shoots and roots of Eucalyptus globulus deprived of nitrogen or treated with salt

We used calorimetry to test whether there is a single general relationship between growth and respiration in shoots and roots of Eucalyptus globulus Labill. seedlings when stressed, irrespective of the type or severity of stress. We found that nitrogen (N) deprivation and salt treatment had no effect on the relationship between growth and respiration and little effect on absolute rates of respiration. Carbon-conversion efficiency (epsilonC) ranged from 0.7 to 0.9 for specific growth rates (R(SG)) greater than 0.3 day(-1). Above an R(SG) of 0.1 day(-1), epsilonC decreased gradually with decreasing R(SG) and between an R(SG) of 0- 0.1 day(-1), epsilonC decreased rapidly. We conclude that the relationship between epsilonC and R(SG) is not greatly affected by salt or N-deprivation stresses. Relationships between gross productivity and epsilonC may be generally applicable, in which case they could improve on the "flat-tax" approach to modeling net primary productivity from gross productivity while avoiding the complexity of more explicit models of plant respiration. However, the relationship between gross productivity and epsilonC was sensitive to temperature and the effect of temperature on epsilonC thus requires further investigation. Nitrogen deprivation caused large decreases in leaf area and shoot to root ratio, and mature leaves of N-deprived plants had lower intrinsic water-use efficiencies than leaves of plants well supplied with nutrients. Nitrogen deprivation increased apical dominance and most of the reduction in leaf area was the result of fewer secondary branches, although leaf size was also reduced. Our results suggest that N deprivation reduces productivity primarily by reducing sink size, rather than sink activity, and that apical dominance may be an important mechanism for maintaining adequate epsilonC in resource-limited conditions.     

Resistance to insect pests: What do legumes have to offer?

Summary Insect pests are major problems for all crops, worldwide. In this review we will focus on legumes, which are attacked by a range of insect pests including pod/seed feeders, defoliators and sap feeders. We review the history of breeding for resistance to insect pests in legumes, which has had mixed success, and discuss further opportunities in this area. We also review the extraordinary array of direct and indirect mechanisms contributing to insect defence in legumes, the understanding and exploitation of which offer opportunities for both legume and non-legume crops. There is also good potential to improve insect resistance in legume crops through a detailed understanding of the signaling pathways that regulate induced responses to insect feeding, and recent progress in this area, primarily obtained from non-legume systems, is reviewed. The importance legumes play in farming systems, their wide range of novel chemistry and the emergence of model systems suitable for genomic approaches present opportunities for research in this area strongly linked to breeding programs to help develop legume crops with enhanced insect resistance. CSIRO’s right to retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged.     

Hereditary hydrocephalus in laboratory-reared golden hamsters (Mesocricetus auratus)

A colony of golden hamsters had an ongoing problem with hydrocephalus. In an attempt to clear the colony of the problem, new breeders from another supplier had been purchased. At termination of a behavioral study, the brain was collected from 35 animals (four of which had died with hydrocephalus during the study) and was examined macroscopically and by light microscopy. Although no animals manifested obvious behavioral changes, 31 of 35 (88.6%, 13/15 males and 18/20 females in control and manipulated groups) had hydrocephalus. Twenty-five animals had macroscopically identifiable hydrocephalus, and six had hydrocephalus identified microscopically. Neither teratogenic concentrations of metals nor mycotoxins were detected in tissues or food, and sera from breeders tested negative for antibodies to Sendai virus, reovirus 3, and lymphocytic choriomeningitis virus. Trial matings of breeders expected to produce hydrocephalic offspring resulted in affected offspring, and mating of breeders expected to produce normal offspring resulted in normal or less-affected offspring. Hydrocephalus was confirmed retrospectively in some breeders. Hereditary hydrocephalus appears to be widespread in hamster stocks in Central Europe. Affected animals do not manifest signs of disease and usually die without obvious premonitory signs. Despite severe hydrocephalus, the animals can breed, and animal handlers do not identify motor deficits or abnormal behavioral activity. This entity is unlike the previously described, hereditary hydrocephalus of hamsters that is phenotypically identifiable and usually is lethal before they attain breeding age.     

High-latitude forcing of the South American summer monsoon during the Last Glacial

The climate of the Last Glacial period (10,000 to 110,000 years ago) was characterized by rapid millennial-scale climate fluctuations termed Dansgaard/Oeschger (D/O) and Heinrich events. We present results from a speleothem-derived proxy of the South American summer monsoon (SASM) from 16,000 to 50,000 years ago that demonstrate the occurrence of D/O cycles and Heinrich events. This tropical Southern Hemisphere monsoon reconstruction illustrates an antiphase relationship to Northern Hemisphere monsoon intensity at the millennial scale. Our results also show an influence of Antarctic millennial-scale climate fluctuations on the SASM. This high-resolution, precisely dated, tropical precipitation record can be used to establish the timing of climate events in the high latitudes of the Northern and Southern Hemispheres.     

A case series of thermal scald injuries in dogs exposed to hot water from garden hoses (garden hose scalding syndrome)

In this report, we present a series of cases of thermal burns (scalds) in dogs resulting from exposure to hot water from a garden hose that had been lying in the sun. These dogs typically inhabited the southern and western regions of the USA, where the recorded high temperatures often exceed 32°C (90°F) during the warm summer months. Dogs with thermal scald injury in these cases presented with linear thermal burns along the dorsum, in addition to a variety of other macroscopic lesions that were dependent upon the degree of burn exposure and ranged from local erythema to ulcerated, necrotic and sloughing skin. Chronic, healed wounds were often alopecic, with markedly thickened skin and characteristically smooth and glassy scar tissue formation. Histologically, the lesions of thermal scald injury in these dogs were indistinguishable from any other second or third degree burn, and consisted of full-thickness dermal and epidermal necrosis with occasional fibrinoid necrosis of vessel walls, vasculitis and intravascular thrombosis. Here, we closely examine 10 cases of dogs with dorsal thermal burns collected from Texas, Arizona, California, Utah, Nevada, Indiana, Michigan and North Carolina and propose the term 'garden hose scalding syndrome (GHS)' to describe this unique type of scald injury.     

中国畜牧业协会禽业分会2008年工作总结及2009年工作计划

2008年对于中国家禽业而言是不平凡的一年,三聚氰胺事件、饲料安全问题、原料价格波动、人感染禽流感等等困扰着整个行业。同样对中国畜牧业协会禽业分会而言,更是忙碌而充实的一年,禽业分会的全体工作人员。始终贯彻“服务行业、服务企业、服务政府”的理念积极主动地开展工作,在工作中充分发挥协会“协调、自律、沟通、维权”的功能,使各项工作开展得井然有序,     

Metabolic changes associated with anaesthesia and cherry poisoning in a pony

Observations  A case of a pony with severe cyanide intoxication as a result of cherry ingestion is presented. General anaesthesia was performed for colic surgery. Severe metabolic lactate acidosis in combination with a high arterial oxygen partial pressure and clinically good peripheral perfusion parameters were the remarkable signs during anaesthesia. Severe hypothermia was obvious during recovery. Ten hours post-surgery the pony was euthanized as a result of neurological signs. The diagnosis of cyanide intoxication was made post-mortem.
Conclusion  Cherry ingestion can lead to lethal cyanide intoxication in horses indicated by severe nonhypoxic lactic acidosis during anaesthesia.     

Quantification of the relationship between the environment and Fusarium head blight, Fusarium pathogen density, and mycotoxins in winter wheat in Europe

Measurements of local environmental conditions, intensity of Fusarium head blight (FHB) in wheat spikes, biomass of Fusarium graminearum, F. culmorum, and F. poae (pathogens causing FHB) and concentration of the mycotoxins deoxynivalenol (DON) and nivalenol (NIV) in harvested wheat grain were obtained in a total of 150 location-years, originating in three European countries (Hungary, Ireland, United Kingdom) from 2001 to 2004. Through window-pane methodology, the length and starting time of temporal windows where the environmental variables were significantly associated with the biological variables were identified. Window lengths of 5 to 30?days were evaluated, with starting times from 18?days before anthesis to harvest. Associations were quantified with nonparametric Spearman correlation coefficients. All biological variables were significantly associated with at least one evaluated environmental variable (P?≤?0.05). Moisture-related variables (e.g., average relative humidity, hours of relative humidity above 80%) had the highest positive correlations with the biological variables, but there also was a significant negative correlation between average temperature and several biological variables. When significant correlations were found, they were generally for all window lengths, but for a limited number of window start times (generally before anthesis for disease index and after anthesis for the toxins and late-season fungal biomasses). Semi-partial Spearman correlation coefficients were used to evaluate the relationship between the environmental variables and the concentration of DON and NIV after the effects of FHB intensity and fungal biomass on the mycotoxins were removed. Significant semi-partial correlations were found between relative humidity variables and DON, and between temperature and relative humidity variables and NIV for time windows that started after anthesis (and not for any earlier time windows). Results confirm that the environment influences disease, fungal biomass, and mycotoxin production, and help refine the time windows where the association is greatest. However, variability in the relationships was high, indicating that no single environmental variable is sufficient for prediction of disease or mycotoxin contamination.