A survey of farmers'' attitudes to services provided by consulting veterinarians to the Western Australian sheep industry

A postal survey was conducted of 80 sheep farmers in the Kojonup and Esperance districts of Western Australia to establish what they wanted from a veterinary service. Twenty five of the farmers surveyed used a sheep consultant, 25 did not, and 30 were interested in employing one. Farmers were asked questions about themselves and their attitudes to private veterinarians who provide specialist services to sheep farmers. Data reported here showed that farmers wanted a veterinarian who lived in the district, was well trained in sheep management and production, was enthusiastic and had good communication skills. The service provided should be whole-farm and available to members of the consultant's group only. Regular newsletters and field days were necessary, but the provision of contract services, such as mulesing, lamb-marking, drenching, pregnancy testing and sheep classing, and 'fire-brigade' services for sick animals, were not rated as important. Most farmers were unwilling or unable to give a dollar value for the likely benefits of a consultancy service. Non-financial benefits included keeping farmers up to date with new technical developments and information. The survey also showed that a veterinarian specialising in services to sheep farmers could be confident of employment.     

Chronic cervical compressive myelopathy in horses: patterns of astrocytosis in the spinal cord

The distribution and morphology of fibrous astrocytes in the cervical spinal cord of normal horses and horses with chronic compressive myelopathy were demonstrated using immunohistochemical staining for glial fibrillary acidic protein. In the spinal cord from normal horses, astrocytes with stellate cell bodies and short processes were irregularly distributed in grey matter. In the white matter, their cell bodies were small and angular in areas adjacent to grey matter and larger and more stellate-shaped in the subpial area. Astrocyte processes were fine, and evenly distributed in a predominantly radial pattern in transverse sections of cord. Gliosis was marked in the spinal cords of horses with cervical compressive myelopathy. In the grey matter at the level of compression astrocytes were often enlarged and rounded, with short, blunt processes, but the gliosis was generally mild. In the white matter, gliosis was obvious in areas of nerve fibre swelling and degeneration at the level of compression and in areas of ascending and descending Wallerian degeneration. The fine radial pattern of astrocyte fibres was replaced by a dense, irregular arrangement. Gliosis persisted in the cords of chronically affected horses after active nerve fibre degeneration had subsided. The areas of gliosis coincided with the areas of Marchi staining for degenerating myelin and with areas of myelin loss in osmium tetroxide post-fixed tissue. Histological observations were consistent with astrocytes replacing areas of extracellular space that remained after nerve fibre degeneration. it is concluded that astrocytic gliosis is a prominent and persistent alteration of the spinal cord of horses with chronic cervical compressive myelopathy.     

Rainfall and breed effects on the efficacy of ivermectin jetting fluid for the prevention of fly strike and treatment of infestations of lice in long-wooled sheep

SUMMARY An ivermectin-based jetting fluid was assessed for its efficacy in the prevention of blowfly strike and treatment of lice in long-wooled sheep. The ivermectin concentrate was diluted to 0.03 mg/mL and applied via a standard hand jetting technique. In insectary studies, using laboratory-reared Lucilia cuprina, sheep jetted with ivermectin were protected from induced breech and body strikes for 18 weeks after treatment. Merino and Corriedale sheep were equally protected, as were sheep subjected to 25 mm simulated rainfall at 1, 3 or 6 hours after jetting. Naturally occurring infestations of lice, Bovicola (Damalinia) ovis, were successfully treated with ivermectin jetting fluid in Merino and Corriedale sheep using a standard hand jetting technique. In addition, the efficacy of treatment was not affected by simulated rainfall at 1, 3 or 6 hours after treatment.     

Acute cortisol responses of lambs castrated and docked using rubber rings with or without a castration clamp

Objective To measure the plasma cortisol response in lambs castrated and docked by three different methods (ring castration and tail docking, ring and clamp castration and tail docking; ring and clamp castration and ring tail docking) for 4 h after treatment.
Design A physiological study with controls.
Procedure A rubber ring was applied to the scrotum. Then the castration clamp was placed, distal to the ring, on each spermatic cord such that there was no overlap of the crush lines.
Results There were no differences in the cortisol secretion of the lambs castrated and tail docked by the ring only and by the ring plus castration clamp methods. Using the castration clamp in addition to the ring on the tail had no effect on cortisol secretion.
Conclusions Using the castration clamp did not appear to reduce the cortisol response to ring castration and docking, as demonstrated elsewhere, because the areas of uncrushed tissue between the two castration clamp crush lines allowed nociception from ischemic scrotal tissue to be transmitted cranially via undamaged nerve fibers.