Clinical findings associated with chronic ischial fracture in a gelding

An 8-year-old show-jumper gelding was referred for examination as a result of a purchase dispute for reported back pain. Clinical examination identified back pain and atrophy of the left semimembranosus and semitendinosus muscles, but no lameness. Standing pelvic radiography demonstrated a chronic nonunion fracture of the left ischium, the clinical significance of which was uncertain. The apparent back pain was thought to be probably unrelated to the pelvic lesion. We conclude that chronic ischial fracture in the horse can lead to specific atrophy of the semimembranosus and semitendinosus muscles, which originate from this bone.     

Establishing a pilot bovine viral diarrhoea virus eradication scheme in Somerset

Beginning in April 2006, 41 farms were recruited onto a pilot Bovine viral diarrhoea virus (BVDV) eradication programme across the south of England with the majority of study herds concentrated in Somerset. Each herd was assessed and where relevant cleared of persistently infected (PI) animals. Seven farms dropped out before whole herd screening could be performed. Of the remaining 34 farms, 20 (59 per cent) were classified as infected although two of these were initially misclassified as BVDV-free. Over the course of three years, 61 PIs were identified across 16 of the 20 infected farms. 72 per cent of PIs indentified on the first herd test were below two years of age. PI prevalence ranged from 0.2 to 3.1 per cent of infected herds and was highest in herds that did not vaccinate. By the end of 2009, 24/34 (71 per cent) of study farms were BVDV-free while 10 (29 per cent) remained infected.     

Pop hole use by hens with different keel fracture status monitored throughout the laying period

The aim of this work was to study the effect of keel fractures on the extent to which free-range hens access the range through pop holes. Over two consecutive laying periods (two production years) a total of 1100 individual birds from one half of a house, divided into four separated flocks, were caught at 25, 35, 45, 55 and 65 weeks, palpated to assess the prevalence and severity of keel fractures and tagged with RFID transponders. Their use of pop holes was subsequently monitored in some cases from week 25 to end of lay at 68 to 70 weeks. At regular intervals (every 10 weeks), the tagged birds were re-caught to assess changes in keel fracture prevalence and severity. The average percentage of birds with fractured keels at 25, 35, 45, 55, 65 and at end of lay (68 to 70 weeks of age) was 5.5, 25.5, 49, 63, 66.5 and 78.5, respectively, across both production years. The effect of keel score on pop hole use was modelled statistically, adjusting for weather conditions and age of the birds. There were significant effects of most of the weather variables recorded, as well as age of the bird, on use of pop holes and also a significant effect of keel score. Higher keel scores resulted in a reduction in pop hole use. A significant statistical interaction between keel score and ambient temperature revealed an accelerated reduction in use as the temperature decreased and keel score increased. It is concluded that the occurrence of keel fractures may affect the birds' ability or willingness to utilise the outdoor range provided by free-range housing systems, thereby reducing the potential welfare advantages of this type of housing.     

Velogenic Newcastle disease in imported caged birds

Velogenic Newcastle disease was diagnosed in pet birds intended for importation into Canada. Virological and histopathological examination confirmed the presence of the disease. The group of birds was denied entry into Canada. Similar birds illegally imported are a potential source of velogenic Newcastle disease virus and are a threat to domestic poultry.     

Treatment of sepsis in the small tarsal joints of 11 horses with gentamicin-impregnated polymethylmethacrylate beads

Gentamicin-impregnated polymethylmethacrylate beads were used to treat infective arthritis in the small tarsal joints of 11 severely lame horses. Under general anaesthesia, between five and 10 beads were placed into a 7 to 8 mm tract drilled across the affected joint and, in all except one horse, they were left in place for 14 days. Two of the horses were euthanased for reasons other than persistent tarsal joint sepsis, but the other nine survived and seven of them returned to their previous level of athletic performance.     

Applying the FAO Guidelines on land evaluation for forestry

This paper describes a trial application of the Food and Agriculture Organization (FAO) Guidelines on Land Evaluation for Forestry, which have been developed at the request of the International Union of Forestry Research Organizations (IUFRO).The study was carried out in mainly unlogged eucalypt forest in the Wandella-Dampier region on the South Coast of New South Wales, Australia. The study area of 49 000 ha was divided into 249 land units on the basis of field survey, as well as aerial photography and map interpretation. Rules were devised for evaluating the suitability of each land unit for the following seven land uses; general forestry, recreation, visual resource protection, flora and fauna protection, catchment protection, undeveloped natural forest and preserved natural forest. The FAO guidelines proved to be an effective basis for forest land evaluation.     

Determining contemporary and historical sediment sources in a large drainage basin impacted by cumulative effects: the regulated Nechako River,British Columbia,Canada

Purpose

Sediment dynamics in most large river basins are influenced by a variety of different natural and anthropogenic pressures, and disentangling these cumulative effects remains a challenge. This study determined the contemporary and historical sources of fine-grained (<?63-μm) sediment in a large, regulated river basin and linked changes in sources to activities in the basin. The river has seen declines in chinook salmon, sockeye salmon, and the endangered Nechako white sturgeon populations, and sediment (both fine-grained and sands) transport and deposition have been identified as potential causes of these declines.

Materials and methods

Samples of suspended sediment and potential source materials were collected from numerous sites distributed throughout the upper Nechako River Basin in British Columbia, Canada. A floodplain sediment core was also collected in order to reconstruct sediment sources over the last ~?70 years. Discriminating fingerprint properties were used within the MixSIAR model to apportion sources among sub-basins and land-use types. Results were compared to records of precipitation and Nechako River discharge trends, and to changes in landscape development.

Results and discussion

Contributions from the erosion of channel banks dominated the suspended sediment load at most sites. Changes in sediment sources during the 2015 field season reflected snowmelt and patterns of water release from the Nechako Reservoir that affected the sediment-carrying capacity of tributaries and the Nechako River main stem. Spatial variations in 2015 also reflected the distribution of land use (e.g., forested or agricultural land) as well as topography (e.g., slope steepness). Over the last ~?70 years, variations in sediment sources and the characteristics of the sediment (e.g., organic matter content and particle size composition) were linked to the construction of the Kenney Dam (operational in 1954) and the impacts of deforestation by the forestry and agricultural industries. Superimposed on these have been wildfires and a major mountain pine beetle infestation leading to higher erosion rates in the affected areas.

Conclusions

The sediment source fingerprinting technique, in combination with historical information on the hydrometeorology and the land use and river management in the basin, has provided valuable information with which to understand sediment dynamics in the Nechako River Basin. Such an approach can help to disentangle how large river systems respond to a combination of natural and anthropogenic pressures.

     

Climatology of Acacia mearnsii. 1. Characteristics of natural sites and exotic plantations

Climatic variation in the natural distribution of Acacia mearnsii in Australia was analysed. Data from sites where the species has been successfully grown in plantations and trials in Africa, Asia and South America were used to determine the species' climatic adaptability. Annual mean temperatures at these plantations and trial sites ranged from 13.9 to 23.9°C, whilst annual mean precipitation ranged from 693 to 2263 mm. The coldest month minimum temperature at these sites was –0.6°C. This information, along with other details of climatic requirements presented in the paper, will assist in selecting sites for future trials at new locations.