ALPACA INTERNAL PARASITE CONTROL –
CHOOSING THE RIGHT DRENCH.

Background.

At a recent Central Coast/Hunter regional Australian Alpaca Association meeting, a member asked for information about drenches used by other alpaca breeders. This is an important issue as in Australia and New Zealand there are no anthelmintics (drenches) registered for use with alpacas. It means breeders using a drench “off the label” need professional advice, usually from a veterinarian. This article is based on online research and a literature review. It is for information only and not intended to replace professional advice. There is a list of members of the Australian Alpaca Veterinarians (AAV) in the back of the Australian Alpaca Industry Directory 2005-2006 for AAA members reference.

Internal Parasites.

Internal parasites if untreated (or the drenches used are not effective) cause problems such as weight loss, ill thrift, anaemia, abortion and if severe enough, intestinal ulceration and death (Cotton, “The Silent Killers”).
Some internal parasites affecting alpacas are:-
1. Round worms (nematodes) such as haemonchus (barber’s pole worm), trichostrongylus (black scour worm), ostertagia or teladorsagia (small brown stomach worm), co operia oncophora (cattle bankrupt worm)
2. Flat worms (cestodes) such as tapeworms (monezia) and
3. Flukes (trematodes) such as fasciola hepatica (liver fluke).

When choosing a drench it is important to know the difference between the drenches on the market, especially when alternating products to assist in the prevention of worm resistance. The website wormboss.com.au “Know your Drench”, developed by the Australian Sheep Industry CRC and Australian Wool Innovation, has excellent information about the drenches on the market, the worms they target and the protective period , that is, how long the treatment is active in the animal. For example, if the breeder has a large property with a quarantine or isolated paddock, they may use a broad spectrum, short acting drench for alpacas that have been purchased elsewhere. Several days after worming they would move the alpacas to a “safe” or “clean” paddock. If the breeders have a smaller property where paddock rotation is not possible, the choices are to use a drench with persistent action ( Closantel or moxidectin), or drench the alpacas more frequently as they will be continuing to ingest worm larvae as they graze. Dr Peter Rourke in his article “Alpaca Parasites” (Alpaca Hmmm, Autumn 2006) reminded breeders in the Mid North Coast area of NSW of the need to increase the frequency of drenching at “high risk times of the year (wet, hot and humid)”. He recommended drenching every 6 weeks at these times, as in this area he stated it’s almost impossible to achieve a safe pasture by spelling.

Frequent drenching can increase the risk of drench resistance, so it is useful to know which worms are developing resistance to drench groups. Stephen Love, veterinarian/State Worm Control Co ordinator, Armidale, reported resistance to Closantel is widespread in northern NSW and south-eastern Queensland. Closantel is a narrow-spectrum drench used against Barber’s Pole Worm (Agnote DAI/87 revised April 2005). Kerri Tyrell of CSIRO Livestock Industries in Armidale NSW, has conducted research to address the problem of worm resistance. She developed and trialled a long-acting capsule which combined tablets of Ivermectin and Levamisole. The trial was conducted using 30 young merinos. Ivermectin alone controlled, but did not eliminate Haemonchus contortus (barber’s pole worm), however the subsequent doses of Levamisole reduced the number of eggs produced by worms 99.9 percent. It seems we cannot rely solely on one drench type to totally alleviate internal parasites.

In Agnote DAI 297, July, 2003, Stephen Love reports ‘multi-active’ or ‘combination’ products have the potential to delay the development of resistance. Combination products such as ‘Q Drench’ and ‘Genesis Xtra’ are increasingly being used by sheep owners however it must be noted that any drench with albendazole poses a risk to animals such as sheep and alpacas in the early stages of pregnancy.

Choosing the right drench- what do veterinarians recommend?

A study of available literature indicates the following drenches have been suggested as suitable for alpacas.

Ewen McMillan, Bellarine Veterinary Practice, Victoria
• Injectible Ivomec, Cydectin. Injectible Cydectin appears to be safe at twice the recommended dose rates for other species.
• Valbazen for tapeworm and liver fluke (not in early stages of pregnancy)
• Fasinex fluke drench

Dr Peter Rourke, The Valley Veterinary Hospital, Wingham, NSW
• Closal for nematodes
• Alben for tapeworms

Alpaca Association- New Zealand
• Ivomec, Genesis, Dectomax: subcutaneous injection (SQ) all 1 ½ x sheep dose….Vetdectin and Cydectin Injection (use double dose)

Andrew Miller BVs
• Ivermectin injection for barbers pole worm at least 4 times per year

Dr Toni Cotton- Camelid Veterinary Services, USA
• Oral wormers: fenbendazole (Panacur); albendazole (Valbazen-but not in first 5 months of pregnancy) or oxfendazole

New Ross Veterinary Services, 2003, USA
• Valbazen sheep dose-not in first 3rd of pregnancy
• Panacur/Safeguard (fenbendazole) 2 x horse dose
• Pyrantel 2 x horse dose
• Ivermectin injectible …if Ivermectin oral sheep drench use 2x horse dose

La Rue Johnson
• Fenbendazole (Panacur) oral for most nematode parasites
• Albendazole (Valbazen) more effective in reducing tapeworms 6.5mg/kg
• Ivermectin injectible also reduces nasal bots , dose 2mg/kg (SQ)

Conclusion.

Injectible Ivomec/Ivermectin and Cydectin seem to be recommended by several veterinarians. In Australia and New Zealand it is mentioned that injectible Cydectin can be given at double the recommended dose rates. Closal /Closantel seem effective against susceptible roundworms unless in a region where resistance has been reported. Valbazen is useful for tapeworms with alpacas but if using for females it should not be used in the early stages of pregnancy. Additional information is available from the NSW Department of Primary Industries, Department of Agriculture and CSIRO Livestock Industries. Many of the online articles were accessed through hyperlinks , so not all reference details were possible.

References.

(1)Alpaca Association New Zealand (April, 2006) Paddock Card- Treatments: Standard Vaccinations and Preventative Treatments.

(2)Australian Wool Innovation Ltd- Know your Drench.
www.wormboss.com.au

(3)Brown Besier (2002) Sheep Worms- Barber’s Pole Worm . Department of Agriculture Farmnote No. 57

(4) Burke, J.- Management of Barber Pole Worm in Sheep and Goats in the Southern US

(5) Cotton, T. The Silent Killers. Camelid Veterinary Services. U.S.A.

(6) Hutchinson, G; Macarthur, E; & Love, S. Worms in Alpaca- Worm Test.
NSW Agriculture . www.agric.nsw.gov.au

(7) Love, S. Barber’s Pole Worm- Haemonchus Contortus
(8) Love, S. Sheep Worm Control and drench resistance- no worries?
Agnote DAI/87 revised April 2005.
www.dpi.nsw.gov.au

(9) Love, S. Combination of sheep drenches, resistance and refugia.
Agnote DAI 297, July, 2003.
www.agric.nsw.gov.au

(10) La Rue Johnson. Herd Health and Management.
www.alpaca.asn.au/info/readings/johnson.shtml

(11) McMillan, E.(2004) Alpaca Herd Management. Bellarine Veterinary Practice, Newcomb, Victoria.

(12) Miller, A. (2001) Barber’s Pole Worm.
www.alpaca.asn.au/nswhawk/barbers.htm

(13) NCSU (1998) Animal Science- Gastrointestinal Parasite Management of Meat Goats . www.cals.ncsu.edu

(14) New Ross Veterinary Services (2003) Parasite Control.
www.newrossvet.com/parasite_control.htm

(15) Oakenful, A. Worms in Alpacas. NSW Agriculture
alpaca-s.com/worms.html

(16)Rourke, P. (2006) Alpaca Parasites. Central Coast and Hunter Region Hmmm-Issue 10/Autumn.

(17) Tyrell, k. (2006) International presentation on sheep worm research- CSIRO Media Release.
www.csiro.au

(18) Queensland Government, Department of Primary Industries and Fisheries. Wormbuster Laboratory Report, May, 2004.
www.dpi.qld.gov.au/sheep/12603.html

Paper prepared by Susan Roberts (Tinonee Alpacas, Taree, NSW ) September, 2006. This may be copied for individual use but not for publication or sale without permission from the author.