THE PREVALENCE OF GASTRO-INTESTINAL NEMATODES AND THE EFFECTS OF GENOTYPE, SEX AND BIRTH TYPE ON GROWTH RATE AND BLOOD CONSTITUENTS IN THAI PRE-WEANING KIDS

摘要

Two consecutive experiments were conducted to study the prevalence of gastro-internal nematodes of Thai native (TN) and cross-bred kids. In experiment 1, a randomised complete block 2~3 factorial design with 3 periods (block) was used. Factors were genotype (Thai native; TN and 50% Anglo-Nubian; AN), sex (male and female) and birth type (single and twin). It was showed that TN kids had significantly (p<0.01) lower egg counts/g of faeces (epg) than 50% TN X 50%AN kids at 8, 9, 10, 11 and 12 weeks of age. There was no significant (p>0.05) difference in haematological values (total protein, albumin, globulin, haemoglobin, (Hb) and packed cell volume, pcv) between genotypes. There was no significant difference in growth rate between genotypes for 0-6 and 6-12 weeks of age. However, crossbred kids had significantly (p<0.01) higher growth rates (24.7 g/kg~(75)/ d) than those of TN (23.0 g/kg~(75)/d) kids. Epg of TN kids was lower than 1,500 from 6-12 weeks of age, but from weeks 9-12 cross-bred kids had1,935-3,054. This result may affect pre-weaning growth rate of the cross-bred kids. This study also presents the effects of sex and birth type on growth rate, prevalence of internal parasites and blood constituents. In experiment 2, 15 TN and 11 50% TN X50% AN kids were used to confirm the prevalence of same parasites in the same season of the following year.