Browsing by Author "Amusan, S.A"

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    DIFFERENTIAL RESPONSES OF NIGERIAN NATIVE SHEEP BREEDS TO ASSAULTS OF SUBACUTE Trypanosoma vivax INFECTION IN THE TROPICS: POLYMERASE CHAIN REACTION-BASED ASSAY EVIDENCES
    (Department of Animal Science, Nasarawa State University, Keffi., 2018-04-03) Yakubu, Abdulmojeed; Ikeobi, C.O.N; Onasanya, Gbolabo O; Sanni, Timothy M; Ozoje, M.O; Amusan, S.A; Decampos, J.S; Ofori, J.A; Ibrahim, A.A
    Molecular-based assay is reported to efficiently detect higher levels of subacute infection of the African Animal Trypanosomosis (AAT). Based on our previous research data, this study reports the detection of subacute Trypanosoma vivax (T. vivax) infection, sequel to polymerase chain reaction (PCR)-based assay diagnosis in four extant Nigerian sheep breeds namely, Balami, Yankassa, Uda and West African Dwarf (WAD) sampled from four geographical locations in Nigeria, the detected T.vivax infection was associated with thermo-tolerance traits of our animals. The study approach involved the use of the PCR-based assay to amplify a DNA fragment size of 400 bp within the genome of the pathogenic parasite in 161 sheep of both sexes. Our findings showed that T. vivax pathogen caused significant assault (P<0.05) on infected Nigerian native sheep compared with non-infected counterparts as depicted by the elevated thermo-tolerance traits. The WAD breed was found to have improved thermo-tolerance performance especially in body temperature when exposed to the assault of T. vivax infection compared with the Uda, Balami and Yankassa sheep breeds (P<0.05). The sheep breed showed very significant effect (P<0.01) on thermo-tolerance traits. Balami sheep was the most thermalvulnerable breed while WAD was least affected by the assault of thermal stress. Pathogenic T. vivax is culpable in the alteration of body thermo-tolerance of local sheep populations in Nigeria with the attendant health implications. Current research noted that WAD breed performed better under stressful assaults of T. vivax infection.
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    GENE FLOW BETWEEN NIGERIAN SHEEP BREEDS AS REVEALED BY MICRO SATELLITE DNA MARKERS
    (Department of Animal Science, Nasarawa State University, Keffi., 2020-02-11) Yakubu, Abdulmojeeb; Agaviezor, B.0; Peters, S.O; Ajayi, F.O; Gunn, Hollingsheed H; Adefenwa, M.A; Adebambo, O.A; Ozoje, M.O; Ikeobi, C.O.N; Wheto, M.; Ajayi, O.O; Amusan, S.A; Ekundayo, J.O; Sanni, Timothy M; Okpeku, M.; Onasanya, Gbolabo O; Donato, Marcos De; Ilori, M.B; Kizilkaya, Kadir; Imumorin, I.G
    The presence and level of gene flow between the four major Nigerian sheep breeds (West African Dwarf (WAD), Yankasa, Balami and Uda) was assessed using microsatellite DNA markers. DNA was extracted from 50~1of whole blood using the ZymoBead™ Genomic DNA Kit The DNA was amplified by PCR in a MyCycler™ Thermal Cycler (Biorad, Hercules, CA) using 15microsatellite markers selected. DNA fragment analysis of microsatellite markers was carried out using the Applied BioSystems 3730xl DNA Analyzer (Applied Biosystems, Carlsbad, CA, USA). The level of gene flow or population structure was assessed by STRUCTURE software and barplots generated by DISTRUCT. At K=2, two clusters was constituted from breeds descending from Balami and Yankasa, both of which are from Northern region in Nigeria. At K=3 and K=4, one more cluster emerged and further analyses did not reveal any additional strong high level substructure, so separating the entire the entire datasets into 3 major clusters was chosen as the final configuration. There are however, several cases of adm ixtures in the genome of some of the individuals that constitute the cluster. Yankasa and Salami breed had more cases of admixtures followed by Udawhile the WAD was the least breed with cases of admixtures
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    Genetic diversity analysis of the mitochondrial D-loop of Nigerian indigenous sheep
    (Department of Animal Science, Nasarawa State University, Keffi., 2012-03-06) Agaviezor, B.O; Adefenwa, M.A; Peters, S.O; Yakubu, Abdulmojeed; Adebambo, O.A; Ozoje, M.O; Ikeobi, C.O.N; Ilori, B.M; Wheto, M.; Ajayi, O.O; Amusan, S.A; Okpeku, M.; Donato, M. De; Imumorin, I.G
    Indigenous livestock resources are strategic in the socio-economics of rural agricultural systems to ensure food security in resourcepoor countries. Therefore, better understanding of genetic variation holds the key to future utilization through conservation. We report the first analysis of genetic diversity of Nigerian sheep based on the D-loop region of the Ovis aries mitochondrial genome using 1 179 bases between sites 15 437 and 16 616 base pairs. A sample of 290 animals made up of Balami, West African Dwarf (WAD), Uda and Yankasa breeds were randomly collected from across Nigeria. Ninety-six haplotypes were observed with a high mean haplotype diversity of 0.899 ± 0.148. Gene diversity was highest in Uda (0.921 ± 0.021) and lowest in WAD (0.852 ± 0.061). Population specific FST indices varied from 0.00133 in Uda to 0.00335 in WAD. Yankasa had the highest number of polymorphic sites (201), while the least was in Uda (96). Analysis of molecular variance revealed that 0.23 percent of the variation is found among populations compared with 99.77 percent variation found within populations. The phylogenetic tree indicates that the mitochondrial lineages of these sheep breeds originated from a common source consistent with first divergence of Yankasa followed by WAD, while Balami and Uda remain more closely related. These results suggest that evolutionary divergence of Nigerian sheep breeds based on mitochondrial DNA D-loop sequence may be coincident with geographical distribution in Nigeria and suggest significant interbreeding. This could have implications for managing improvement and conservation strategies and long-term conservation of Nigerian indigenous sheep.
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    Morphological and microsatellite DNA diversity of Nigerian indigenous sheep
    (Department of Animal Science, Nasarawa State University, Keffi., 2012-04-22) Agaviezor, B.O; Peters, S,O; Adefenwa, Mufliat A; Yakubu, Abdulmojeed; Adebambo, O.A; Ozoje, M.O; Ikeobi, C.O.N; Wheto, M.; Ajayi, O.O; Amusan, S.A; Ekundayo, Oludotun J; Sanni, Timothy M; Okpeku, M; Onasanya, Gbolabo O; Donato, Marcos De; Ilori, Babatunde M; Kizilkaya, Kadir; Imumorin, I.G
    Background: Sheep is important in the socio-economic lives of people around the world. It is estimated that more than half of our once common livestock breeds are now endangered. Since genetic characterization of Nigerian sheep is still lacking, we analyzed ten morphological traits on 402 animals and 15 microsatellite DNA markers in 384 animals of the 4 Nigerian sheep breeds to better understand genetic diversity for breeding management and germplasm conservation. Results: Morphological traits of Uda and Balami were significantly (P < 0.05) higher than Yankasa, which were both higher than West African Dwarf (WAD) sheep. Stepwise discriminant analysis showed tail length, rump height, chest girth, ear length and chest depth as the most discriminating variables for classification. Mahalanobis distances show the least differentiation between Uda and Balami and the largest between WAD and Balami sheep. While 93.3% of WAD sheep were correctly assigned to their source genetic group, 63.9% of Yankasa, 61.2% of Balami and 45.2% of Uda were classified correctly by nearest neighbour discriminant analysis. The overall high Polymorphism Information Content (PIC) of all microsatellite markers ranged from 0.751 to 0.927 supporting their use in genetic characterization. Expected heterozygosity was high for all loci (0.783 to 0.93). Mean heterozygote deficiency across all populations (0.171 to 0.534) possibly indicate significant inbreeding (P < 0.05). Mean values for FST, FIT and FIS statistics across all loci were 0.088, 0.394 and 0.336 respectively. Yankasa and Balami are the most closely related breeds (DA = 0.184) while WAD and Balami are the farthest apart breeds (DA = 0.665), which is coincident with distance based on morphological analysis and population structure assessed by STRUCTURE. Conclusions: These results suggest that within-breed genetic variation in Nigerian sheep is higher than between-breeds and may be a valuable tool for genetic improvement and conservation. The higher genetic variability in Yankasa suggests the presence of unique ancestral alleles reflecting the presence of certain functional genes which may result in better adaptability in more agro-ecological zones of Nigeria. These genetic characteristics are potentially useful in planning improvement and conservation strategies in Nigerian indigenous sheep
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    Single nucleotide polymorphisms at heat shock protein 90 gene and their association with thermo-tolerance potential in selected indigenous Nigerian cattle
    (Department of Animal Science, Nasarawa State University, Keffi., 2020-06-28) Yakubu, Abdulmojeed; Onasanya, Gbolabo O; Msalya, G.M; Thiruvenkadan, A.K; Sreekumar, Chirukandoth; Tirumurugaan, Gopalan K.; Okpeku, M.; Sanni, Timothy M; Decampos, J.S; Amusan, S.A; Olowofeso, Oladeji; Fafiolu, A.O; Ikeobi, C.O.N
    Heat shock protein (HSP) 90 gene provides protection and adaptation to thermal assault and certain polymorphisms have been associated to heat tolerance in humans and animals. Single nucleotide polymorphisms (SNPs) of HSP 90 gene were used to evaluate the scientific basis of heat tolerance in four zebu breeds of Nigeria. The DNA was extracted from skin tissue of 90 adult bulls representing White Fulani (WF), Sokoto Gudali (SG), Red Bororo (RB), and Ambala (AM). The SNPs were determined in DNAs using PCR, sequencing, and visualization and bio-editing by chromatogram in SeqMan Ngen tool. Subsequently, respective genotypes were constructed and genotypic and allelic frequencies were computed. Also, body parameters related to heat stress (HS) including body temperature (BT), rectal temperature (RT), and respiratory rates (RR) were taken for each animal before biological sampling and heat tolerance coefficient (HTC) was calculated. We detected four SNPs distinct/specific for each breed as follows: change from thymine (T) to guanine (G) at position 116 (T116G) in RB, G to cytosine (C) at 220 (G220C) in SG, G to adenine (A) at two positions, 346 (G346A) and 390 (G390A) in AM and WF, respectively. Heterozygous SNPs showed significantly lower values (P < 0.0001) for BT, RT, RR, and HTC than homozygous genotypes at all positions.We hypothesize that animals with heterozygous SNPs in exon 3 of HSP 90 may be tolerant to HS. These SNPs can be used as bio-markers for screening large populations of cattle for tolerance to hot tropical conditions in Nigeria and other sub-humid places.