BIOCHEMICAL RESPONSES OF YANKASA SHEEP TO EXPERIMENTAL FASCIOLA GIGANTICA INFECTION IN ZARIA, NIGERIA.

Abstract

A study was conducted to determine the biochemical responses of Yankasa ewes to experimental Fasciola gigantica infection for a period of 10 weeks. A total of 12 Yankasa ewes were used in the experiment and were obtained from the Reproduction Unit of the National Animal Production Research Institute, Shika-Zaria, Nigeria. 2 weeks baseline pre-infection data were collected and the ewes were later divided into two groups of infected and controls. The six animals in the infected group were each orally inoculated with 1200 Fasciola gigantica metacercariae and monitored for a period of 16 weeks. The pathogenic effects of Fasciola gigantica infection began to manifest as of 9th week post infection through clinical symptoms of bottle jaw, emaciation, depression and pallor of mucus membrane among the infected group. Eggs were demonstrated in faeces of the infected animals at 12th week post-infection. The pathogenic effect was also evident based on fluke biomass, mean fluke length and width, degree of liver damage, serum AST, ALT, ALP and electrolytes responses. There was an increased level of AST from the 4th week post-infection indicating greater damage to the liver parenchyma while the levels of ALT began to rise at the 9th week post -infection among the infected group indicating epithelial damage in the bile ducts. The findings of this study reveals the diagnostic potentials of liver enzymes in the early detection of ovine fasciolosis.