South East Local Land Services animal health update March 2022

Japanese encephalitis detected in samples from NSW piggeries

NSW pig and livestock owners are urged to be alert for signs of Japanese encephalitis in their animals, following the detection of Japanese encephalitis virus (JEV) in samples from multiple commercial piggeries.

Pig owners in particular are encouraged to be alert to the signs of JEV. These include reproductive failure in pigs, with 50–70 per cent losses reported in affected populations. Pregnant sows and gilts may abort, produce mummified or malformed foetuses, or give birth to stillborn or weak piglets at term.

Boars can be affected with genital swelling and temporary or permanent infertility. Nervous signs such as tremors and convulsions are occasionally seen in pigs up to six months of age.

If you suspect JE in pigs or other livestock, you must report it to the 24-hour Emergency Animal Disease Hotline on 1800 675 888.

Scabby mouth in sheep

Photosensitisation has been seen in sheep and cattle in the last month causing facial and other skin lesions. These lesions develop after eating a toxic plant, fungae infested plant or even after grazing high chlorophyl containing plants. After eating these offending plants, the skin becomes hypersensitive to sunlight. This results in a range of skin lesions including: swelling of the ears, face and muzzle, difficulty breathing, droopy ears, scabby skin lesions on the nose, face and udders and sloughing skin.

Sporadic cases of photosensitisation are seen on grazing lucerne, clover, cereal crops or canola. Weeds such as Patterson’s curse, Heliotrope, Fireweed, St John’s wort, Panic spp. grasses and Tribulus spp. can all cause photosensitisation via different mechanisms. Treatment is removal from affected paddock, shade, and supportive care.

SOUTH EAST LOCAL LAND SERVICES PARABOSS REPORT MARCH 2022

South Eastern Tablelands: Peter Rolfe, District Veterinarian - Yass

The excellent seasonal conditions have continued with associated internal parasitism, especially in weaner lambs and rising yearling cattle. In lambs, the nematode infections have progressed in composition from mainly Teladorsagia spp (brown stomach worm) to a mix of that genera and Haemonchus contortus (barber’s pole worm). The latter is difficult to predict given that mostly summers are erratically dry, but this long mild wet summer has suited barbers pole worm. This emphasises the need for regular worm egg counting and species identification to guide control options. The treatment options that are available for long-acting control of H. contortus will depend on the degree of resistance to either moxidectin or closantel. Resistance would appear to be widespread to both so ongoing monitoring of treatment response with egg count are required. Increasingly vaccine is being used to manage this parasite in the face of what appear in recent years to be increasing prevalence and importance.

Liver fluke can be expected to cause more serious concerns in the coming autumn and winter with more favourable conditions for snail multiplication in the spring of 2021. Pasture conditions are generally good although cattle are grazing lower, wetter areas in response to carryover of long and rank feed base. This will be exacerbated as autumn and winter progresses. Choice of treatment options will vary according to the time of the year and product however generally treatment of livestock in autumn and early winter needs to be effective against adult and immature fluke and those in the spring, effective against adult flukes.

South East-Coastal: Evelyn Walker, DV Berry

On the South Coast, worm egg counts have ranged from very low, moderate to high in both cattle and sheep.

Adult beef cattle in the Shoalhaven area for example with only mild weight loss in some animals had nil worm egg counts at a post drench check. Others in this same herd however, had low to moderate worm burdens (ranging from 120 and up to 360 strongyle epg). Interestingly, these results were in animals that had missed a drench and did not have obvious weight loss. This highlights the value of using worm egg count testing as a monitoring tool even in the absence of clinical symptoms such as weight loss. On other another property in the Shoalhaven area, weaner calves were reported with chronic weight loss and diarrhoea. Worm egg counts indicated that affected calves not only had a severe worm burden (3,300 strongyle epg), but also had liver fluke infection.

Of the reports received, sheep on the coast that were drenched in December and moved onto fresh pasture are now starting to show mild to moderate increases in worm burdens consisting of primarily 80 per cent Barber’s pole worm and 20 per cent Black scour worm. Liver fluke has also been detected in sheep with no overt symptoms of liver fluke infection such as bottle jaw, presence of anaemia (pale or white gums and conjunctiva) or jaundice (yellowing of the gums or conjunctiva.) Remember these signs-anaemia and bottle jaw are also signs of Barber’s pole worm infection.

Ongoing wet conditions continue to be favourable for worms, fluke and biting insect activity on the coast. Check your livestock now with a worm egg count and do some fluke monitoring to see whether your animals require treatment. Mosquitos, ticks and flies are on the rise too. These insect vectors can transmit significant diseases like three-day sickness and theileria in cattle and pink eye in both cattle and sheep. Ensure livestock are up to date on their tick, fly and lice treatments.

FIT TO LOAD: EYE DISEASE AND BLINDNESS