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The retail cuts, gut characteristics and morphology of rabbits fed with varying dietary fibre and digestible energy (DE) levels were measured in a 70-d feeding trial using 135 weaner rabbits. The experiment was designed as a 3 × 3 factorial arrangement of treatments having 3 levels of dietary fibre (low, optimum and high) and 3 levels of DE (low, optimum and high). The rabbits were allotted to 9 dietary groups consisting of 15 rabbits each. Main effect of fibre and DE showed that dressing out percentage (P < 0.05), chilled carcass weight (P

Newcastle disease and heat stress reduce the productivity of local chickens of Nigeria (LCN). This study compared the antibody response to Newcastle disease and heat tolerance among different LCN genotypes in hot humid tropics using multivariate discriminant analysis. A total of 299 birds were used for the study. Geometric mean titre against Newcastle disease before vaccination (GMTB), geometric mean titre against Newcastle disease after vaccination (GMTA), rectal temperature at week 4 (RT4), pulse rate at week 4 (PR4), respiratory rate at week 4 (RR4), heat stress index at week 4 (H4), rectal temperature at week 13 (RT13), pulse rate at week 13 (PR13), respiratory rate at week 13 (RR13) and heat stress index at week 13 (H13) were measured. All the traits were significantly (p

The effects of plumage colour on different behaviours have been reported in several avian species, but there are only few studies for Nigerian indigenous turkeys (NIT). Fear is a negative affective state that is indicative of suffering and associated with adverse effects on welfare and productivity of livestock species. This study compared fear behaviours in NIT with different plumage colours during early life (first 16 days of life). Seventy-five birds (25 each of white, black and lavender) were used in this study. The three colour phenotypes were derived from the same genetic line. Tonic immobility, emergence, open field, inversion and attention bias tests were done at 7, 9, 12, 14 and 16 days old, respectively. Data were analysed with Kruskal-Wallis tests. The durations of tonic immobility and freezing during the attention bias test were not significantly associated with plumage colour (χ2 =1.7592, df=2, p = 0.42 and χ2 =3.9421, df=2, p = 0.14, respectively). The latency to emerge from a dark box was significantly related to plumage colour (χ2 =8.9229, df=2, p = 0.01), with the shortest emergence latency observed in black NIT. There was a significant plumage colour effect on the duration of ambulation (χ2 =9.6013, df=2, p = 0.01) and a significant effect on the percentage of floor squares explored by the birds in the open field test (χ2 =6.1191, df=2, p = 0.05). The least ambulation time was observed in black NIT (p = 0.02). Lavender turkeys explored fewer floor squares compared to black and white NIT (p = 0.04). The frequency of escape attempts was significantly associated with the plumage colour of the birds (χ2 =11.6810, df=2, p = 0.00). The highest frequency of escape attempts during the open field test was observed in black birds, while there was no significant difference in the frequency of escape attempts of white and lavender birds. There were no plumage colour effects on the duration of preening (χ2 =1.5896, df=2, p = 0.45), wall pecking (χ2 =3.3346, df=2, p = 0.19) and floor pecking (χ2 =1.7483, df=2, p = 0.42) of NIT in the open field test. The results from this study applied to the early life stage. It can be concluded that plumage colour influenced the level of fear in young NIT, with lavender turkeys being the most fearful in three out of the four statistically significant fear indicators (longer emergence duration, lower number of escape attempts and lower percentage of floor squares explored in an open field test), followed by white, whereas black turkeys were least fearful.

Understanding the level of genetic diversity in any population is an important requisite towards strategizing measures for conservation and improvement of stocks. This study focused on the assessment of phylogenetics and molecular divergence of tilapia fish species obtained from two populations (Domita in South-South and Odeda in South-West, Nigeria) using the displacement loop (D-loop) and cytochrome b region of the mitochondrial deoxyribonucleic acid (mtDNA). A total of 28 samples (15 from South-South and 13 from South-West) were used for the genetic analysis. DNA was extracted from the tissue of all the samples using Quik-gDNATM miniPrep kit. The D-loop containing the hypervariable region was sequenced for all samples from the two populations, while cytochrome b (Cyt b) region of mtDNA was only sequenced for samples from South-South population. Chromatograms of the sequences were viewed and edited using Bioedit software. Multiple sequence alignment was carried out using molecular evolutionary genetic analysis (MEGA) software before subsequent genetic analyses. Phylogenetic analysis grouped the samples into two clusters based on population. Also, when the two mitochondrial regions were pooled together, they clustered into two major groups based on mitochondrial regions. Analysis of molecular variance (AMOVA) revealed 37.32% variation within population and 62.68% variation among population with a significant fixation index of 0.627 (p < 0.05). The genetic distance inferred between D-loop regions of South-South and South-West populations was 0.243. Maternal lineage analysis revealed that the origin of tilapia fish from both populations could be traced to Oreochromis spirilus and Oreochromis leucostictus based on mitochondrial D-loop region. The findings of this study revealed molecular divergence among the tilapia populations and may serve as pivot information for the genetic improvement of this important species.

Deciphering genomic information requires markers that are polymorphic and sufficient enough to capture its vast array of genetic data. Polymorphic loci can differ greatly between breeds of the same species and the exclusion of the Nigerian and some African sheep breeds during the development of the OvineSNP50 chip necessitated the validation of SNPs included on the chip to allow for genomic applications of the excluded breeds. A total of sixty sheep samples were genotyped [10 each of the Balami, Uda, West African Dwarf and Yankasa from Nigeria, Dorper and Red Maasai from Kenya (East Africa)] using the Ovine 50k Illumina SNP bead chip. Results revealed that 33,994 SNPs (97.47%) of the called 34,876 SNPs were validated for downstream analysis. Mean heterozygosity values of 0.154 and 0.153 were obtained for polymorphic SNPs on sex and autosomal chromosomes respectively, while the values of 0.662 and 0.054 were obtained on the sex and autosomal chromosomes respectively for the mean identity-bystate (IBS). Six and three individuals violated the per ID and identity-by-state (IBS) thresholds, respectively. It was observed that the Ovine 50k Illumina SNP bead chip was informative in the Nigerian and East African sheep that were studied, and should be useful in examining the underlying genetic variation. Keywords: Sheep, OvineSNP50, genome-wide, call rate, minor allele frequency

In this study, the maternal genetic diversity and phylogenetic relationship of Nigerian duck populations were assessed. A total of 591 base pair fragment of the mitochondrial DNA (mtDNA) D-loop region of 87 indigenous ducks from two populations in Nigeria were analyzed. Seven haplotypes and 70 polymorphic sites were identified. The mean haplotypic and nucleotide diversity were found to be 0.381±0.058 and 0.315±0.155 respectively. The phylogeny revealed two divergent haplotype clades, suggesting two possible maternal lineage in Nigerian duck population, with the most commonly shared haplotype belonging to Mallard ducks ( Anas platyrhynchos ). Genetic variation within and between populations accounted for 63.32% and 36.68% of the total genetic variation respectively. This study concluded that there was relatively high genetic diversity and differentiation, thus, this information will probably pave way for further evaluation studies, preservation and improvement of Nigerian ducks as genetic resources. Keywords : Genetic Diversity, MtDNA, Nigerian duck, phylogeny

Egeria radiata is a benthic species of bivalves which inhabits freshwater bodies along the coast of Nigeria. It’s an edible species with shells of nutrient value used in animal feeds and healthcare industries. This research was undertaken to investigate its species diversity in some coastal populations in Nigeria. Partial sequence of Cytochrome b region of mitochondrial DNA extracted from 53 samples from three locations (Itu 17, Southern Ijaw 18 and Burutu 18) in the Niger delta region of Nigeria were sequenced, aligned and subjected to haplotype network analysis. Afterwards, MEGA 6.06 was used in the analysis of genetic distance, selection and some diversity-based parameters. Results showed high transversion and non-synonymous substitution in Itu population. Polymorphic sites and haplotype diversity was high across the populations (0.88 [Image: see text] ” 0.96), indicating considerable diversity of the sequences. Nucleotide diversity was highest in Itu population. Graphical display of relationship among the haplotypes of pooled samples did not show population-based discrimination. Within-population genetic distance was least in Burutu (0.003), while between-population genetic distance was least between Burutu and Southern Ijaw (0.014). In addition, diversity indicated by genetic distance and diversity indices was not severe. Phylogenetics and median-joining network analyses did not segregate the populations into well-defined clades. Selection analysis revealed large site indices for both positive and negative selection in Itu, but more of neutral selection in the other two populations. Tajima’s D and Fu’s F values for neutrality test showed no significance difference (P>0.01) in each case. However, negative D value was obtained for the three populations. The rate of population growth or expansion was higher in Burutu than Itu and Southern Ijaw. Egeria radiata showed no maternal relationship with the other bivalve species based on the cytochrome b gene region used in this study.