Some differences between eight grasses within the Lolium-Festuca complex when grown in conditions of severe water shortage

Differences between eight related grasses within the Lolium-Festuca complex in conditions of severe water shortage were investigated. Transparent covers were used to restrict the access of rain to field plots of pure stands of Westerwolds ryegrass ( Lolium multiflorum var. Westerwoldicum), Italian ryegrass ( L. multiflorum ), hybrid ryegrass ( L. multiflorum × L. perenne ), perennial ryegrass ( L. perenne ), meadow fescue ( Festuca pratensis ), Italian ryegrass × meadow fescue, perennial ryegrass × meadow rescue, tall fescue ( Festuca arundinacea ) and three mixtures (Italian ryegrass with perennial ryegrass; Italian ryegrass with tall fescue; perennial ryegrass with tall rescue) grown in west Wales. Westerwolds ryegrass and Italian ryegrass died out after 12–15 months of exclusion of rain; meadow fescue, meadow rescue × ryegrass hybrids and perennial ryegrass died out after ≊ 2 years of exclusion of rain; tall rescue was still alive after 4 years of exclusion of rain. During the 2 years after the year of sowing, the loss of water from the top 1 m of soil was greater with tall rescue than with the other grasses. Tall fescue and perennial ryegrass had a low rate of leaf expansion, a small increase in length of exposed leaf sheath and a high weight per unit area of emerging leaf blade. Tall rescue had a greater number and weight of roots than the other grasses, particularly in the 50–100 cm layer of soil, on an adjoining, uncovered site. The order of suitability of the eight grasses for conditions of severe water shortage appears to be tall fescue > perennial ryegrass > perennial ryegrass × meadow rescue, meadow fescue, Italian ryegrass × meadow rescue, hybrid ryegrass > Italian ryegrass > Westerwolds ryegrass.     

An application of data envelopment analysis to investigate the efficiency of lumber industry in northwestern Ontario, Canada

This study aims at exploring the technical efficiency of lumber industry in northwestern Ontario,Canada using data envelopment analysis(DEA).The DEA model analyzes relative technical efficiency of lumber mills with disproportionate inputs and outputs by dividing the 10year time series data,for inputs and outputs of 24 lumber mills,over two periods(1999-2003 and 2004-2008).Four inputs,namely,material(log volume),labour(man-hours),two types of energy(hog-fuel and electricity),and one output(lumber volume) are used in this study.The trend analysis shows an annual reduction of 10%,13% and 13% for lumber output,log consumption(input) and number of employees,respectively,during the period 1999-2008.The results from DEA with two scenarios with energy inputs and without energy inputs,for the two periods are found to be mixed and interesting.While some mills have improved their performance in terms of best use of available scarce inputs in the second period,some have shown negative per cent change in efficiency.In the with energy input and the without energy input scenario,some of the mills show a reduction in efficiency in the second period from the first period,with the highest estimated reductions of-13.9% and-47.6%,respectively.A possible explanation for these negative performances of mills in the latter period is the decline in production in the second period compared to the first period,where these mills were not able to adjust their inputs(mostly labour) as proportional lay-offs might not have been possible.These results provide policy makers and industry stakeholders with an improved understanding of the trends of efficiency and employment as well as reallocation opportunities of future inputs in order to increase benefits from this sector.     

Chemical Usurpation of a Nest by Paper Wasp Parasites

The paper wasp Polistes atrimandibularis is an obligatory social parasite of another Polistes species, P. biglumis bimaculatus. To control the host nest, the parasite sequentially changes the composition of its chemical signature, the cuticular hydrocarbons, during the colonial cycle. Gas chromatography-mass spectrometry of the cuticular hydrocarbons at every stage of the cycle showed that the parasite can switch on and off an entire chemical family, namely, the unsaturated hydrocarbons. In this way the parasite can match the host signature at a critical moment of the colonial cycle.     

Behavioural and EEG changes in sheep in response to painful acute electrical stimuli

Objective To measure acute pain in sheep, based on a human pain model, and examined changes in both electroencephalogram frequency spectrum and behavioural responses to increased electrical stimulation in sheep. Design Analysis of variance (treatment and animal effects) for stimulus intensity where each animal received each electric shock treatment given in the order 0, 5,10 and 20 mA. Procedure Eight sheep with electrodes implanted over the surface of the brain were examined for escape-avoidance and electroencephalogram responses to four levels of electrical stimulation from 0–20 mA. Results With increasing stimulus intensity at the time of feeding, the sheep were more hesitant to return to the feeder or remain near the feeder following stimulation. There was little difference between the 0 and 5 mA stimuli for any of the behaviour variables (P > 0.05). However, there were marked increases in the time taken to re-approach the feeder after receiving an electric shock of 5 mA and of 20 mA (P < 0.05; mean values 3 and 119 s, respectively) and remaining near the feeder for 5 s (P < 0.001; mean values 10 and 167 s, respectively). Following the stimulus, there was an overall increase in the electroencephalogram power spectrum in the first four seconds, which then rapidly returned to normal. In particular, the 20 mA stimulus resulted in higher absolute power values than in the control (0 mA) treatment for delta 2 (P < 0.001), theta 1 (P < 0.05), theta 2 (P < 0.05), alpha 1 (P < 0.001), alpha 2 (P < 0.001) and beta 1 (P < 0.01) band-widths. Similarly, for the 10 mA stimulus, the absolute power values were greater than the control treatment for delta 2 (P < 0.05), alpha 1 (P < 0.01), alpha 2 (P < 0.001) and beta 1 (P < 0.01) bandwidths. Conclusion The experiment suggests that a human acute pain model is applicable to sheep and that these electroencephalogram changes may provide a good measure of acute pain in sheep.     

Fasciola hepatica infection in farmed emus (Dromaius novaehollandiae)

Objective To describe two cases of infection with Fasciola hepatica i n young farmed emus, subacute and chronic fasci-olosis and a response to treatment of the flock with albenda-zole.
Procedure Gross lesions were found at necropsy and hepatic lesions in microscopic examination. The parasite recovered from one emu was identified by its morphological characteristics and an egg count reduction test was carried out after treatment of the flock with albendazole.
Results Hepatic lesions resembling subacute and chronic fasciolosis of ruminants were identified. An adult fluke was recovered from the liver of one of the birds and was identified as F hepatica . The eggs of the fluke were irregular in shape and size. No fluke eggs were identifiable in faeces of live emus 10 days after treatment of the flock with albendazole at a dose of 10 mg/kg.
Conclusions This is the first reported case of infection with F hepatica i n farmed emus and the first report of the occurrence of Fasciola infection is the class Aves. The irregular shape and size of the eggs may be attributable to infection of an aberrant host. Treatment with albendazole eliminated eggs from the faeces of the flock.     

Muscle strain injuries of the hindlimb in eight horses: diagnostic imaging,management and outcomes

Objective To describe the clinical presentation, ultrasound findings, management and outcome in horses with muscle tear injuries of the hindlimbs. Design Retrospective case series Procedure Medical records of eight horses were reviewed and information on signalment, history, presenting complaint, physical examination findings and further diagnostic tests were recorded. Diagnosis of muscle injury was determined by the presence of abnormal ultrasound findings, compared with the contralateral limb, and, when required, nuclear scintigraphy. Follow-up information was obtained via telephone interviews with owners, trainers and referring veterinarians. Results Muscle tears causing lameness were identified in the middle gluteal (3), semitendinosus (1), semimembranosus (2) and gracilis (2) muscles. Tears were classified by ultrasound imaging as partial (6) or complete (2). The degree of lameness did not appear to be indicative of the extent of injury or of completion of healing. Long-term follow-up was available for seven horses and the outcome was favourable in six cases. Conclusions and clinical relevance Ultrasonography is useful in the diagnosis and assessment of moderate to severe muscle strain injuries. The prognosis appears to be favourable in most cases, although recurrence of injury and lameness can delay the return to athletic activity and an inferior outcome with persistent gait abnormality may occur.     

Superior check ligament desmotomy for treatment of superficial digital flexor tendonitis in Thoroughbred and Standardbred horses

Summary Bilateral superior check ligament desmotomy was performed on 31 Thoroughbred and 17 Standardbred horses as the sole method of treatment for superficial digital flexor tendonitis. Horses resumed racing between 6 and 19 months after surgery. Horses that were able to compete in 5 or more races without injury to the tendon again were considered to have had a successful return to racing. Twenty-five Thoroughbreds were suitable for later study and 13 of these (52%) raced on 5 or more occasions. Fifteen Standardbreds were suitable for later study and 10 of these (66%) raced on 5 or more occasions. Within the racing industry it is generally thought that about 20 to 30% of horses with superficial digital flexor tendonitis can return to racing after a prolonged rest. The results of this study suggest that bilateral superior check ligament desmotomy may improve the prognosis for a horse returning to racing after injury to the superficial digital flexor tendon.