An abattoir survey on the occurrence and prevalence of swine parasitic helminths of public health and economic importance in kenya
Abstract
Although there have been systematic and well coordinated efforts in
documenting the prevalences of parasitic diseases of the pig in several countries of
the world, very little has been done in Kenya. Parasitic helminths, specifically, have
negative impacts on the health of the pigs, health of the consumers of pork and
other products and the economics of the swine industry. The present study focused
mainly on those parasites encountered during routine post-mortem meat inspection
in Kenya with emphasis on those of public health and economic importance.
Using records kept by the Ministry of Agriculture and Rural Development,
"a retrospective abattoir survey was carried out to determine the occurence and
prevalences of the various pig parasitic helminths of public health and economic
importance encountered during the routine abattoir meat inspection over a ten year
period (1988-1997) in Kenya. In addition, a cross-sectional survey was carried out
in Nairobi's Farmers' Choice and Ndumboini abattoirs where routine physical meat
inspection was done. Faecal and diaphragm muscle samples were collected for
laboratory faecal egg analyses and trichinoscopy respectively. Faecal samples were
quantitatively analysed for faecal helminth egg counts (eggs per gramme of
sample) using the McMaster Technique, while the diaphragm muscle samples were
analysed by trichniscopy for Trichinella spiralis larvae.
A total of 642,295 pigs were slaughtered during the 1988-1997 period. Out
of these, 31,365 (4.9%) had Ascaris suum (indicated by the presence of milk spots
in the liver), 4,733 (0.7%) had hydatid 'cysts in the liver, lungs and spleen, 215
(0.03%) had lung worms, 165 (0.03%) had liver flukes and 38 (0.01%) had
nodular worms belonging to Oesophagostomum dentatum and 23 (0.004%) had
Cyticercus cellulosae.
The cross-sectional post -mortem meat inspection performed revealed that
Ascaris suum had a prevalence of 27.1%, hydatid cysts had 5.7% while
Oesophagostomum dentatum, had a prevalence of 5.7%. On quantitative fecal egg
counts of strongyles, Ascaris suum, Trichuris suis and coccidia showed
prevalences of 50.9%, 10.7%," 3.6% and 15.2% respectively. Trichinella spirallis
was never detected.
These results therefore show that Ascaris suum had the highest prevalence.
Generally, the prevalences of the other pig parasitic helminths were low.
The presence of these parasites which are also of public
health (zoonotic) importance in this country therefore calls for interventionary
efforts in order to avert potential health hazards to consumers of pork and its
products.
Citation
Masters Degree in Veterinary Public Health, University of Nairobi, 1999Publisher
University of Nairobi Department of Public Health, Pharmacology and Toxicology, University of Nairobi, Kenya