Livestock Disease Trends (as informally reported by vets in South Africa) January 2013

Due to good rainfall in the summer rainfall areas and hot weather, numerous reports of internal parasites were received. Infestations were reported at:

Livestock Disease Trends (as informally reported by vets in South Africa) January 2013
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Mpumalanga

  • Balfour: wireworms. Ermelo, Piet Retief, Middelburg and Volksrust: roundworms. Mbombela: roundworms – high rainfall, humidity and intensive grazing contributed to high parasite infestation on especially kikuyu and star grass pastures here. Even animals grazing on veld pastures show signs of infestation. Animals are kraaled at night to prevent theft and the concentration of livestock around kraals/camps/water troughs contributes to the infestation.

Gauteng

  • Bronkhorstspruit and Onderstepoort: roundworms.

Limpopo

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  • Polokwane: roundworms. Vaalwater: animals dying due to wireworm infestation.

North West

  • Brits, Stella and Christiana: roundworms. Leeudoringstad: wireworm in sheep; bankrupt worm in goats. Ventersdorp: wireworm.

Free State

  • Clocolan, Frankfort, Hoopstad, Kroonstad, Reitz, Viljoenskroon and Harrismith: roundworms (few cases of severe infestation seen in Harrismith; reasonable control on most farms, with grazing management and treatment.) Heilbron: roundworms – some anthelmintics don’t stop mortalities; cydectin is recommended in this area. Villiers: wireworms and bankrupt worms.

KwaZulu-Natal

  • Bergville: roundworms – young lambs on kikuyu; poor gowth, weakness, and emaciation. Creighton, Dundee, Estcourt, Mooi River and Mtubatuba: roundworms. Dundee: high roundworm egg counts, but the majority of sheep have responded well to treatment.

Eastern Cape

  • Aliwal North: wireworm. Graaff-Reinet: roundworms – monitoring of internal parasites still a problem here and farmers aren’t up to date with their control measures. Humansdorp: roundworms. Stutterheim: wireworm outbreaks and resistance a problem. Doing tests to find what anthelmintics are effective and advising farmers accordingly. Protein nutrition also emphasised. Protein deficiency in sheep due to large numbers of brown stomach worm. Kraaling the problem.

Western Cape

  • Caledon and George: roundworms. Darling: ewes before lambing had a medium infestation of roundworms. Treatment is not done routinely before sheep go to stubble lands. Wellington: Brown stomach worm caused some deaths.

As noted, some farmers weren’t up to date with their control programmes. They should discuss which active anthelmintic groups to use with their vet as numerous reports of resistance to drugs were received. A faecal egg count reduction test should be done.

  • Clinical signs of Parafilaria infestations were reported from mainly the bushveld areas. Animals should be treated for 70 days with an approved product before slaughter to allow the false bruising lesions to heal.
  • Reports of tapeworms were received from Balfour, Mbombela and Volksrust (Mpumalanga); Bronkhorstspruit and Onderstepoort (Gauteng); Polokwane (Limpopo); Brits (North West); Parys, Viljoenskroon and Villiers (Free State); and Underberg (KZN).

Some were resistant to certain anthelmintics An outbreak of Coenurus cerebralis (tapeworm cysts on the brain) was also reported. To prevent this, dogs should be treated regularly with praziquantel and the heads of these dead sheep burnt.

  • Liver fluke infestations were rife and even occurred in an area where never seen before. It’s important to remember that clinical signs are very similar to that of wireworm as they include anaemia and bottle jaw.
  • Be aware that conical fluke outbreaks have been reported. The most important clinical sign of this disease is a profuse projectile diarrhoea.
  • Increasing numbers of blue, brown ear, bont-legged and heartwater ticks were reported. It’s important that farmers should know the life cycles of these parasites as this is the key to their control. For example, the immature stages of brown ear-ticks should be controlled in winter so as to prevent high adult tick numbers in summer. (Farmer’s Weekly will soon be running a series on ticks in our ‘Back To Basics’ section.)

The use of acaricides in a control programme should be discussed with your vet so as to slow down the selection for tick resistance against the macrocyclic lactones now used excessively against blue ticks.

  • Tick-transmitted diseases such as African and Asiatic red water, anaplasmosis, heartwater and sweating sickness were reported from many areas. Contact your vet to update the treatment protocols for the various diseases and to discuss the vaccination programmes to prevent these diseases from occurring.
  • Nuisance and biting flies have been reported in great numbers. These parasites are also transmitting various pathogens causing conditions such as opthalmia, mastitis, diarrhoea and fly worry. Discuss control programmes with your vet.
  • Midges, biting flies and mosquitoes were reported from many areas. These are carriers of blue tongue, three-day stiff sickness, lumpy skin disease, Rift Valley fever, Wesselsbron disease and horse sickness. Outbreaks of all these (except for Rift Valley and Wesselsbron) were reported. Animals should be vaccinated against these diseases before the rainy season. 

If an outbreak occurs try to move animals to high lying areas away from water sources, spray animals with a pyrethroid registered for use against insects and stable valuable animals at night.

  • Venereal diseases such as trichomonosis and vibriosis are still on the increase causing huge economical losses. Contact your vet to discuss your biosecurity programme and to bring it up to date.
  • In spite of vaccines available against the clostridial diseases gasgangrene, botulism, pulpy kidney, red and blood gut and tetanus, these diseases are reported on a monthly basis. Either animals are not vaccinated or something has gone awry. 
  • Brucellosis is out of hand and all farmers should be aware of the danger of bringing this disease onto their farm. Strict biosecurity measures should be followed to prevent a disaster.
  • Bovine malignant catarrh (snotsiekte) is still taking its toll every month. It’s important that cattle farmers adjacent game farms get sufficient knowledge on how this disease is spread.

The following poisonings were reported: urea, tulip, Cestrum, prussic poisoning, acidosis, sulphides in water, ergot, gousiekte, geeldikkop, slangkop, lead, photosensitization, mycotoxicosis, Thesium lineatum (witstorm) and Ornithogalum toxicarum.

Feedlot report

Cattle

  • Deaths occurred due to blackquarter in spite of good vaccination programmes. There were even cattle in the final feed programme that died. In one case Clostridium septicum was isolated.
  • Bovine malignant catarrh (snotsiekte) again caused losses. 
  • Foot rot occurred in the very wet feedlots. 
  • Deaths due to red gut, bloat and pneumonia occurred due to unfavourable weather conditions. 
  • Tick transmitted diseases were responsible for numerous deaths. 

The following were seen at abattoirs: parafilaria – cattle from the northern part of the country; measles – sporadic, mostly calcified lesions which indicate that infestation took place in the pre-feedlot period; also seen in the livers of a large group of animals most probably due to jackal or dog tapeworms (Taenia hydatigenia); condemnation of livers due to liver fluke occurred sporadically – in one case the intermediate hosts (snails) were found in the water reservoir of the feedlot.

Sheep

  • Numerous orf cases in lambs.
  • Pulpy kidney and pneumonia mortalities in lambs.
  • Coccidiosis present in numerous feedlots.
  • Many lambs arrived with severe wireworm infestations.
  • The lungs of a group of lambs were condemned due to Corynebacterium pseudotuberculosis abscesses. They had poor growth.