Mathew Wheto

Association of SNP variants of MHC Class II DRB gene with thermo-physiological traits in tropical goats

Host defense in vertebrates depend on many secreted regulatory proteins such as major histocompatibility complex (MHC) class II which provide important regulatory and effector functions of T cells. Gene polymorphism in the second exon of Capra-DRB gene in three major Nigerian goat breeds [West African Dwarf (WAD), Red Sokoto (RS), and Sahel (SH)] was analyzed by restriction fragment length polymorphisms (RFLP). Four restriction enzymes, BsaHI, AluI, HaeIII, and SacII, were utilized. The association between the polymorphic sites and some heat tolerance traits were also investigated in a total of 70 WAD, 90 RS, and 50 SH goats. Fourteen different types of alleles identified in the Nigerian goats, four of which were found in the peptide coding region (A57G, Q89R, G104D, and T112I), indicate a high degree of polymorphism at the DRB locus in this species. An obvious excess (P < 0.01) of non-synonymous substitutions than synonymous (dN/dS) in this locus is a reflection of adaptive evolution and positive selection. The phylogenetic trees revealed largely species-wise clustering in DRB gene. BsaHI, AluI, HaeIII, and SacII genotype frequencies were in Hardy-Weinberg equilibrium (P > 0.05), except AluI in RS goats and HaeIII in WAD goats (P < 0.05). The expected heterozygosity (H), which is a measure of gene diversity in the goat populations, ranged from 0.16 to 0.50. Genotypes AA (BsaHI), GG, GC and CC (AluI) and GG, GA, AA (HaeIII) appeared better in terms of heat tolerance. The heat-tolerant ability of SH and RS goats to the hot and humid tropical environment of Nigeria seemed better than that of the WAD goats. Sex effect (P < 0.05) was mainly on pulse rate and heat stress index, while there were varying interaction effects on heat tolerance. Variation at the DRB locus may prove to be important in possible selection and breeding for genetic resistance to heat stress in the tropics.

Interrelationship studies between heat stress traits, blood andserum biochemical indices of extensively managed Nigerian Sheep

The exposure of sheep to elevated ambient temperatures induces an increase in the dissipation of excess body heat, in order to overcome this excessive environmental heat load. Dissipation of excess body heat is emitted by evaporation of water from the respiratory tract and skin surface via panting and sweating.The following heat stress traits were measured; body temperature, rectal temperature, pulse rate and respiratory rate after the sunrise and before the sunset. While blood and serum biochemical indices measured were blood glucose, total serum protein, globulin, cholesterol and triglycerides. No significant relationship(P>0.05) was recorded between heat stress traits and blood biochemical indices studied. However, we observed a positively significant (P<0.01) relationship betweenblood and serum biochemical indices studied. Similarly, a positively significant (P<0.01) relationship was observed between heat stress traits examined.

Mitochondrial DNA hypervariable region 1 diversity in Nigerian goats – CORRIGENDUM

Moses Okpeku, Sunday O. Peters, Ikhide G. Imumorin, Kyle C. Caires, Varun K. Sharma, Mathew Wheto, Rakesh Tamang, Adeyemi S. Adenaike, Michael O. Ozoje and Kumarasamy Thangaraj doi: 10.1017/S2078633616000102, Published by Cambridge University Press, 3 January 2017 In the above publication (Okpeku, 2017) the incorrect affiliation was given for Kyle Caires. The correct affiliation is: Department of Human Nutrition, Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaì i at M anoa, Honolulu, HI 96822, USA

Mitochondrial DNA hypervariable region 1 diversity in Nigerian goats

espanolLas cabras constituyen el mayor grupo de ganado rumiante en Nigeria y desempenan un papel estrategico en el aporte de proteina animal y en la mejora de la economia de los hogares rurales. Se investigo acerca de la region hipervariable 1 (HVR1) del genoma mitocondrial caprino con el fin de comprender mejor la importancia de la diversidad genetica para mejorar la seleccion en los programas de mejora y conservacion animal. Se secuencio y se analizo la region hipervariable 1 del ADN mitocondrial (HVR1) en 291 cabras autoctonas de Nigeria no relacionadas (Enana de Africa Occidental (EAO), Roja de Sokoto (RS) y Sahel (S)), seleccionadas aleatoriamente a lo largo del pais y comparadas con las secuencias HVR1 de 336 cabras indias y con otras 12 secuencias de 5 especies diferentes del generoCapra (C. falconeri, C. ibex nubiana, C. aegagrus, C. cylindricornis yC. sibirica). Un total de 139 sitios polimorficos de 291 individuos se concentraron en 204 haplotipos. La variacion intra- e interpoblacional fue de 77,25 por ciento y de 22,74 por ciento, respectivamente. Las cabras nigerianas mostraron una elevada diversidad genetica (0,87) y unos valores de FST elevados, distintos de los de las cabras indias y de los de las otras especies salvajes. De acuerdo con los haplogrupos, la cabra EAO se desliga de poblaciones concomitantes de RS y S con una historia demografica diferente. Se identifico una estructura genetica clara entre las razas caprinas de Nigeria, con una variacion apreciable en la region HVR1 del ADN mitocondrial. Este estudio agrupo las razas caprinas nigerianas en dos grupos principales, sugiriendo asi dos origenes demograficos distintos para las razas septentrionales y meridionales. El alto grado de mezcla genetica denota origenes maternos distintos, a diferencia de lo observado en cabras del Levante y Asia Central, donde se domesticaron originalmente las cabras. Palabras clave: diversidad genetica, cabras, region hipervariable, ADN mitocondrial, Nigeria EnglishGoats make up the largest group of ruminant livestock in Nigeria and are strategic in bridging animal protein supply gap and improving the economy of rural households. The hypervariable region 1 (HVR1) of the caprine mitochondrial genome was investigated to better understand genetic diversity important for improving selection for animal breeding and conservation programs. We sequenced and analysed the mitochondrial DNA (mtDNA) HVR1 in 291 unrelated indigenous Nigerian goats (West African Dwarf (WAD), Red Sokoto (RSO) and Sahel (SAH)), randomly sampled from around the country, and compared them with the HVR1 sequences of 336 Indian goats and 12 other sequences in five different species in the genusCapra (C. falconeri, C. ibex nubiana, C. aegagrus, C. cylindricornis andC. sibirica). A total of 139 polymorphic sites from 291 individuals were captured in 204 haplotypes. Within and among population variations were 77.25 and 22.74 percent, respectively. Nigerian goats showed high genetic diversity (0.87) and high FST values, and separate from Indian goats and other wild species. Haplogroups in WAD separates it from RSO and SAH concomitant with a differentdemographic history. Clear genetic structure was found among Nigerian goat breeds with appreciable variation in mtDNA HVR1 region. This study grouped Nigerian goat breeds into two major groups suggesting two different demographic origins for Northern and Southern breeds. High genetic admixing denotes different maternal origins and in contrast to evidence from goats from Levant and Central Asia, where goats were originally domesticated. Keywords: genetic diversity, goats, hypervariable region, mitochondrial DNA, Nigeria francaisLes caprins constituent le plus grand groupe de ruminants domestiques au Nigeria et jouent un role strategique dans l’approvisionnement en proteines animales et dans l’amelioration de l’economie des menages ruraux. Une recherche a ete menee a propos de la region hypervariable 1 (HVR1) du genome mitochondrial caprin dans le but de mieux comprendre l’importance de la diversite genetique pour ameliorer la selection dans les programmes d’amelioration genetique et de conservation des animaux. La region hypervariable 1 de l’ADN mitochondrial (HVR1) a ete sequencee et analysee chez 291 chevres indigenes du Nigeria, sans rapport entre elles (Naine d’Afrique Occidentale (NAO), Rouge de Sokoto (RS) et Sahel (S)), echantillonnees de maniere aleatoire a travers le pays et comparees avec les sequences HVR1 de 336 chevres indiennes et avec 12 autres sequences de 5 especes differentes du genre Capra (C. falconeri, C. ibex nubiana, C. aegagrus, C. cylindricornis et C. sibirica). Un total de 139 sites polymorphes de 291 individus a ete rassemble en 204 haplotypes. La variation intra- et inter-populationnelle a ete de 77,25 pour cent et de 22,74 pour cent, respectivement. Les caprins nigerians ont montre une grande diversite genetique (0,87) et des valeurs de FST elevees et differentes de celles des chevres indiennes et de celles des autres especes sauvages. D’apres les haplogroupes, la chevre NAO serait a separer des populations concomitantes de RS et S avec une histoire demographique differente. Une structure genetique claire a ete decelee entre les races caprines du Nigeria, avec une variation substantielle dans la region HVR1 de l’ADN mitochondrial. Cette etude a regroupe les races caprines nigerianes en deux groupes principaux, ce qui suggere deux origines demographiques differentes pour les races du Nord et du Sud. Le fort degre de melange genetique denote des origines maternelles differentes, contrairement a ce qui a ete observe chez les chevres du Levant et d’Asie Centrale, ou les caprins furent d’abord domestiques. Mots-cles: diversite genetique, caprins, region hypervariable, ADN mitochondrial, Nigeria