The current status and outlook for insecticide,acaricide and anthelmintic resistances across the Australian ruminant livestock industries: assessing the threat these resistances pose to the livestock sector

The Australian ruminant livestock industries are faced with the need to control parasitic infectious diseases that can seriously impact the health of animals. However, increasing levels of resistance to insecticides, anthelmintics and acaricides are substantially reducing the ability to control some of these parasites. Here we review the current situation with regard to chemical resistances in parasites across the various sectors of the Australian ruminant livestock industries and assess the level of threat that these resistances pose to the sustainability of these sectors in the short to long terms. We also look at the extent to which testing for resistance occurs across the various industry sectors, and hence how well-informed these sectors are of the extent of chemical resistance. We examine on-farm management practices, breeding of parasite-resistant animals, and non-chemical therapeutics that may act as short to long term means to reduce the current reliance on chemicals for parasite control. Finally, we look at the balance between the prevalence and magnitude of current resistances and the availability and adoption rates of management, breeding and therapeutic alternatives in order to assess the parasite control outlook for the various industry sectors.     

Islander: A golden nematode resistant potato variety for fresh market and chipping

The Islander potato variety is a medium maturing variety with oblong, shallow-eyed, white-skinned tubers. High dry matter and good chip color characterize this variety which is better adapted to Long Island, New York and New Jersey than to other northeastern areas. It is resistant to golden nematode and net necrosis; moderately resistant to common scab and early blight; and less susceptible than most varieties to acid scab and Rhizoctonia. The Islander is a product of the cross Chipbelle × Norchip.     

Campbell 14: A verticillium resistant round white potato variety

The Campbell 14 potato variety is a medium-late maturing variety with round to oblong, smooth, shallow-eyed, white tubers. This variety is intended primarily for fresh market; however, under some conditions chip color will be acceptable. Campbell 14 is resistant to verticillium wilt and to the net necrosis caused by the potato leafroll virus.     

Yankee Supreme: A new bruise-resistant potato variety

The Yankee Supreme potato is a medium to medium-late maturing variety with round to oblong, moderately smooth, shallow-eyed, buff-colored tubers. It is characterized by bruise resistance and high dry matter. Tubers can be used for fresh market or processing. Although chip color is often marginal, this variety can be reconditioned to its original color after cold storage. Yankee Supreme is resistant to virus X and to net necrosis caused by the leaf-roll virus.     

The effect of Imidan on the flavor of riced baked potatoes

Samples of Irish potato (Solanum tuberosum) from untreated and Imidan 50-WP—treated plots (four applications, 2.24 kg 50-WP/ha) were evaluated for flavor by a sensory panel of 16 judges. Although the sample means were statistically different (P = 0.05), no off-flavor was associated with the Imidan-treated baked potatoes.     

Cerebellar cortical abiotrophy in Wiltshire sheep

AIM: To investigate the nature of a neurological disease in Wiltshire sheep.

METHODS: Three affected lambs were examined, humanely killed and necropsied. Selected neurological tissues were examined by light and electron microscopy.

RESULTS: Primary neurological lesions were confined to the cerebellum and were characterised by loss of Purkinje cells and the presence of large hypertrophied dendrites of surviving Purkinje cells. These contained stacks of smooth endoplasmic reticulum. There was hyperplasia and cell swelling of Bergmann glia. Mild Wallerian-type degeneration affected white matter in the cerebellum and spinal cord.

CONCLUSION: The cerebellar lesions were of a degenerative and reactive rather than hypoplastic nature. These, and the history, suggest a genetic cause with putative inheritance as an autosomal recessive trait. Accordingly, the disorder is described as a cerebellar abiotrophy.