Abstract:
The goal of this work was to improve productivity of indigenous Guinea fowl varieties
in Ghana. The objectives were to: (1) estimate average values of traits and verify sex
and seasonal effects on traits; (2) determine disease resistance in local Guinea fowls
using using SRBC as an indicator trait; (3) measure DOC in local Guinea fowls by the
use of cage score and heterophil/lymphocyte ratio; (4) estimate phenotypic and genetic
parameters and (5) estimate genetic gain of 3rd generation birds for body weight, disease
resistance and DOC. The study was conducted at the Animal farm of the Department
of Animal Science Education, University of Education, Winneba, Mampong-Ashanti
campus, Ghana. Data used was obtained from four varieties of indigenous Guinea fowls
which were randomly picked from a large population and reared from 2015-2018. Data
was analyzed using General Linear Model (GLM) procedure of Statistical Analysis
System (SAS for Windows, version 7). Pearl Guinea fowls had better (p<0.05) body
weight, body weight gain, EGGWT and HDEP relative to the other varieties. Keets
hatched in the minor rainy and dry seasons had better (p<0.05) HWT. Body weight was
higher (p<0.05) during the major rainy season at 8, 16, 24 and 32. Daily weight gain
was higher (p<0.05) in the dry season at 8-16 weeks of age and was better (p<0.05) in
the major and minor rainy seasons at 16-24 weeks. Lavender varieties laid their first
eggs earlier (p<0.05) than their other counterparts. FERT was higher (p<0.05) in the
Pearls than in the other varieties. Black strain showed the best (p<0.05) HATCH
potentials. Lavender, White and Black strains produced more (p<0.05) protein in the
meat compared to the Pearl. The White strain had the best (p<0.05) DRESSP. Lavender
was the most (p<0.05) docile strain. Pre-brooding survival was higher (p<0.05) in the
Pearls and lower (p˃0.05) in the Black. Post-brooding survival was higher (p<0.05) in
males than in females. FCR was better (p<0.05) for bids hatched during the dry season.
University of Education,Winneba http://ir.uew.edu.gh
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The Pearl genotype had the highest (p<0.05) immune competence. Antibody response
to SRBC antigen was better (p<0.05) in females than in males. Intravenous injection
was more effective (p<0.05) in presenting SRBC antigen to immunocompetent cells
than the intramuscular injection. Body weight and EMWTG showed the highest
(p<0.05) additive genetic variation. Direct heritability estimates in the Guinea fowls
were high for HWT, 2 and 4 months body weight, moderate at 6 and 8 in both males
and females. The heritability estimates of body weight gains were moderate at month 2
and 6 but low at month 4 and 8 in the males whereas in the female counterparts the
estimates were moderate at month 2 and 4 and low at 6 and 8. Heritability estimates for
SVV, DRESSP and FI were all low in the males and females apart from FI which was
medium in the females. DOC and FCR heritability estimates were moderate in both
males and females. Estimates of heritability of EGGWT and HDEP were high,
moderate at ATFE and low for FERT and HATCH. Genetic and phenotypic correlations
among HWT, TMWT, FMWT, SMWT, EMWT, TMWTG, FMWTG, SMWTG,
EMWT, FI, FCR, DRESSP, SVV, DOC, ATFE, HDEP and EGGWT were moderate to
high and positive.The mean response for each trait improved in the positive direction
over the three generations of selection. ATFE, egg numbers and weight, growth traits
and docility were affected to a very large extent by additive genetic effect and genetic
selection can be used to improve them. Moderate to high positive genetic correlation
existing in the SMWT, DOC and SVV is an indication that these traits could be
exploited in multiple trait selection using the selection index.
Description:
A thesis in the Department of Animal Science Education,
College of Agriculture Education, submitted to the School of
Graduate Studies in partial fulfilment
of the requirments for the award of the degree of
Doctor of Philosophy
(Animal Breeding and Genetics)
in University of Education, Winneba.