Prevalence and distribution of gastrointestinal helminths and their effects on weight gain in free-range chickens in Central Zambia.
Examination of helminths from gastrointestinal tracts of 125 free-range chickens in Zambia revealed a 95.2% prevalence rate. The species and their prevalences were: Allodapa suctoria (85.6%), Tetrameres americana (80.8%), Ascaridia galli (28.8%), Gonglonema ingluvicola (50.4%), Raillietina spp. (81.6%) and Heterakis gallinarum (32.8%). No trematodes or Syngamus trachea were found. Mixed infections accounted for 88.2% as compared to 7.2% of single infections. Effects of helminthoses on weight gain were investigated in 100 growing chickens randomly assigned to treatment (levamisole) and untreated control groups. There was a significant mean (+/- SEM) weight gain (grams) of 812.8 +/- 51.4 in the treatment group and 623 +/- 57.4 in the control group (p < 0.01). The mean (+/- SEM) worm burdens from the control group and the treatment group were 96.3 +/- 5.61 and 22.05 +/- 2.61, respectively. These results confirm the higher risk of helminth infections in free-range systems and may explain the deleterious effects in chickens.
Phiri
I K
IK
Department of Clinical Studies, School of Veterinary Medicine, The University of Zambia, PO Box 32379, Lusaka, Zambia.
Phiri
A M
AM
Ziela
M
M
Chota
A
A
Masuku
M
M
Monrad
J
J
D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use*; D002645:Chickens / Q000254:growth & development; D004064:Digestive System / Q000469:parasitology; D005243:Feces / Q000469:parasitology; D005260:Female; D006374:Helminthiasis, Animal / Q000188:drug therapy / Q000453:epidemiology*; D007978:Levamisole / Q000627:therapeutic use*; D008297:Male; D010270:Parasite Egg Count / Q000662:veterinary; D011201:Poultry Diseases / Q000188:drug therapy / Q000453:epidemiology*; D015995:Prevalence; D011897:Random Allocation; D015430:Weight Gain; D015024:Zambia / Q000453:epidemiology
D000871:Anthelmintics; D007978:Levamisole