Response of goats to natural helminth infection was investigated among
277 Nigerian indigenous goats belonging to three different breeds [West
African dwarf (WAD), Red Sokoto (RS) and Sahel White (SW)] through the
determination of parasitological and haematological parameters. The
results showed that 65% of the sampled animals were positive for one
helminth or two. Mixed infection due to Haemonchus contortus and
Trichostrongylus colubriformis constituted 33.33% prevalence rate,
while Haemonchus contortus and Oesophagostomum columbianum mixed
infection had 26.67% rate of infection among the sampled animals.
However, single infection due to either of Haemonchus contortus,
Oesophagostomum columbianum, Trichostrongylus colubriformis,
Strongyloides papilosus , Cooperia punctata , Trichuris ovis ,
Paramphistomum cervi and Moniezia benedini constituted 5.0%. There
was no significant (p>0.05) difference in mean faecal egg count
(FEC) among the breeds investigated. Similarly, correlation coefficient
between Haemonchus worm count (HWC) and FEC showed positive correlation
value which was significantly (p<0.01) higher among WAD (0.661) than
SW (0.427) and RS (0.350) breeds. Three (3) different haemoglobin types
(HbAA, HbAB and HbBB) were detected among the goats investigated. Goats
with HbAA showed significantly (p<0.05) higher PCV compared to those
with HbAB/HbBB alleles. In addition, Sahel White and Red Sokoto breeds
had microcytic, hypochromic anaemia with a significantly (p<0.05)
lower haematocrit values than the West African Dwarf breed. Eosinophil
count of RS and SW goats did not vary significantly between the
parasitized and the non-parasitized goats. However, in WAD, the
eosinophil count was significantly higher (p<0.05) in parasitized
than non-parasitized goats. In conclusion, the WAD breed appears to be
more resistant to helminthes infections and H. contortus in particular,
than RS and SW, and this may be due to high frequency of HbAA alleles
in this breed. The advantage of this relative resistance could be
exploited by crossbreeding WAD with other breeds