Andrew Biddle, Northern Tablelands Local Land Services District Vet
With livestock prices breaking records weekly, keeping your stock in good health is a no-brainer!
Local Land Services District Vets and Livestock Officers are fielding an increasing number of enquiries about ill-thrift in weaner sheep, drench resistance, three-day sickness in cattle and buffalo fly.
Ill thrift in weaner sheep
A spike in health issues and deaths in sheep, particularly amongst weaners, has prompted a call to farmers to investigate ill thrift early and take action before problems spread to the rest of the mob.
Factors behind the spate of ill health and increased mortalities include nutrition (sheep battling long grass or overgrazing small areas of short feed in large paddocks, may not be able to access adequate nutrients), worms, liver fluke, Mycoplasma ovis (a blood parasite of sheep that cause anaemia), pink eye induced blindness, pneumonia, scouring and breech strike.
Producers should aim to keep weaner weights up around 23kgs. Lighter lambs will have lower muscle and fat reserves and are more likely to struggle to fight off common health problems.
Most sheep producers on the Northern Tablelands are currently dealing with worms and the biggest challenge when dealing with worms is drench resistance.
You will know if there is drench resistance in your flock if you see signs of wormy sheep within a few weeks of drenching. An effective drench kills all worms and provides at least 4 weeks protection. Anything less means worms survived the drench and are continuing to affect your sheep.
To determine if your drench is working, a simple worm test 10 to 14 days after drenching, will confirm whether adult worms survived the drench. If there are worm eggs, you need to closely monitor the sheep you drenched and select an alternative drench for future use.
If you know worms have built up resistance to drenches on your property, they do not revert to being effective over time. Resistance is genetic so each generation of worms pass their tricks on. Some of the newer drench actives in Zolvix and Startect currently have very little reported resistance. Combination drenches may be effective depending on your individual property resistance profile.
Northern Tablelands cattle producers are advised to be on the lookout for Ephemeral Fever, also known as three-day sickness, as reported cases have emerged recently on the Northern Tablelands.
Once bitten by insects that carry the virus, symptoms of three-day sickness progress rapidly. Animals develop a very high temperature, appear depressed, lethargic and are reluctant to eat and they will often appear lame and stiff when they walk. A nasal discharge is also common.
Once recumbent, larger animals such as bulls, bullocks and pregnant cows will critically deteriorate. While laying down for long periods, nerves and blood flow to the legs can be impacted and animals have difficultly regaining their feet. If left untreated, these animals may die. Recumbent animals are also at risk of pneumonia.
Treatment of animals is important. Intervene early and aggressively.
The humid, stormy weather of the past few weeks has seen an increase in reports of buffalo fly infestations.
The buffalo fly is a small biting fly, about 4mm long in size. It feeds off cattle and buffalo and causes irritation that can result in significant weight loss and a decline in milk production. Many infested cattle also develop sores in the inner corners of their eyes.
Farmers should report buffalo fly sightings so we can get a better idea of how many properties may be affected and how far they have spread as the movement of infested animals can also spread the fly to new sites.
Cattle that are particularly sensitive to fly bites may scratch and rub themselves constantly. Bulls and dark-coated cattle, especially black cattle, appear to be the most prone to severe infestation.
Good management strategies can reduce the impact of disease and other health problems and the financial benefits are worth the effort.