Microsoft word - aa service bulletin_intestinal worms.doc

Treatment of Intestinal Worms in Broiler Breeders July 2008
Summary Provided by Dr. Suzanne Young, Aviagen and Dr. James Dawe, Bayer Animal Health


In recent years, all FDA approved intestinal worm treatments administered in poultry feed have been withdrawn from the US
market. This left the industry dependent on piperazine, the only water administered deworming drug approved for poultry.
Piperazine is commonly used in both preventative and treatment programs. Due to widespread usage of piperazine, the
industry suspects worms are building some resistance against this drug, possibly resulting in more intestinal worm outbreaks.

Intestinal worms are commonly diagnosed during necropsy of pullets, cockerels and occasionally broilers. A preventative
worming program is suggested in rearing breeders to reduce the incidence and severity of intestinal worms. Severe intestinal
worm infestations can cause diarrhea, poor absorption of nutrients, and enteritis. Clinical signs commonly seen with intestinal
worm infestations include rough feathering, retarded growth, pasty vents and pale birds. Worms can be carriers of infectious
diseases, including blackhead (Histomonas meleagridis), (see the Arbor Acres Service Bulletin titled Histomoniasis, July
2008, for more information) which has been diagnosed more frequently in recent months. Early preventative programs are
necessary for control of intestinal worms.
Cleaning out houses and placing new litter with every flock will minimize exposure to intestinal worms. Not only do houses
containing built-up litter harbor intestinal worm eggs that could affect the next flock, they also serve as a reservoir for darkling
beetles that are associated as carriers for worm transmission. Although preventative programs are ideal, occasionally
outbreaks will occur. Table 1 below describes the most common intestinal worms in chickens; Table 2 summaries treatment
options.
Table 1: Common Intestinal Worms of Chickens
Age of birds
Common Name
Scientific
Location
when adult
Description
Intermediate
Treatment
worms first
(Ascarid)
Tapeworm
Capillaria
Cecal Worm

Piperazine is the only FDA approved drug for treatment of roundworms in poultry. Currently, there are no approved drugs
for treatment of Capillaria, tape or cecal worms in poultry. As a result, the drugs below (other than piperazine) are used
extra-label in drinking water when prescribed and monitored by a licensed veterinarian.
9 FDA prohibits extra-label drug use in feed; therefore all treatments must be administered via drinking
9 Follow all manufacturer recommended doses.
9 Consult your veterinarian for prescriptions and withdrawal times.

Table 2: Extra-Label Drugs Used for Treatment of Intestinal Worms via Drinking Water
Active Ingredient
Trade Name
Susceptible
Problems and
Drug Side Effects
Piperazine
2. Water soluble 1. No effect on egg production or performance when used 8-16mg/lb body Levamisole
Hydrochloride
Albendazole
Capillaria, cecal No reported negative effects Oxfendazole
Fenbendazole
Ivermectin
HELPFUL HINTS WHEN CALCULATING DOSAGES
1. Calculate total body weight of flock (kg or lbs) 2. Dose mg X (lb in flock) = Total mg for flock 3. Be sure active ingredient and dose are in the same unit. 1g = 1000 mg 4. Total grams needed for flock / grams active ingredient per package = # of packages for flock
CALCULATION EXAMPLE
1. A house with 9000, 5 lb females and 900, 5.5 lb males: 9000 (5) + 900 (5.5) = ~49,950 total lbs in flock 49,950 lbs X 16 mg = 799,200 mg total for house 3. To convert to grams: 799,200/1000 = 799.2 g 4. If there are 544.5 g of active ingredient per packet: 799.2 g needed / 544.5 g active ingredient = ~1.5 packages for that flock
REFERENCES
1. Dawe, J. and C.L. Hofacre, April 2002. With Hygromycin Gone, What are Today’s Worming Options? The Poultry 2. McDougald, L.R. 2003. Internal Parasites. In: Diseases of Poultry. Y.M. Saif (ed.) 11th ed. Iowa State University

Source: http://www.aviagen.com/assets/Tech_Center/AA_Technical_Articles/AAServiceBulletinIntestinalWorms.pdf