Sunday Peters

Uridine diphospho N-acetylgalactosaminyltransferases (GALNT) are a family of enzymes involved in mucin-type O-glycosylation of serine and threonine residues of polypeptide acceptors. A total of 20 members of the GALNT family of genes were identified and analyzed in the bovine genome which included 14 UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase (GALNT) and 6 UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase-like (GALNTL) genes. Chromosomal locations, genomic structures, identity and similarity between family members, secondary and tertiary structures, phylogenetic analysis and sequence motifs and domains were determined. The genes are located across the bovine genome in chromosomes 1, 2, 4, 5, 7, 8, 10, 11, 15, 17, 24, 25 and 28. Number of exons ranged from 1 exon in GALNT4 to 15 exons in GALNT2. Family members shared a high identity index which ranged from 32% (GALNTL2 and GALNTL4) to 85% (GALNT1 and GALNT13). Simil...

ENGLISH/ ABSTRACT [ENGLISH/ ABSTRACT [ENGLISH/ ABSTRACT [ENGLISH/ANGLAIS ANGLAIS ANGLAIS ANGLAIS] ] ] ] This study is focused on the effect of coat pigmentation and wattle genes on the adaptation performance of West African Dwarf (WAD) goats in the sub-humid zone of Nigeria using purposive sampling method on-farm. Data on white blood cell, red blood cell, haemoglobin, packed cell volume; sodium and potassium were obtained from five hundred and twenty (520) goats. Data were corrected for age effect and for the fixed effect of coat pigmentation and wattle genes using General Linear Model procedure of SAS. White blood cell (WBC), red blood cell (RBC), haemoglobin (Hb), packed cell volume (PCV), serum sodium (Na +) and potassium (K +) were significantly (p < 0.05) influenced by coat pigmentation genes. Brown goats with white markings (aabbss) had the highest WBC (13.01±0.19x10 3 /µl), Na + (138.22±0.74 mmol/litre) and K + (3.80±0.06 mmol/litre) while Bezoar (A bz) goats had the highe...

Measures of heifer fertility are economically relevant traits for beef production systems and knowledge of candidate genes could be incorporated into future genomic selection strategies. Ten traits related to growth and fertility were measured in 890 Brangus heifers (3/8 Brahman × 5/8 Angus, from 67 sires). These traits were: BW and hip height adjusted to 205 and 365 d of age, postweaning ADG, yearling assessment of carcass traits (i.e., back fat thickness, intramuscular fat, and LM area), as well as heifer pregnancy and first service conception (FSC). These fertility traits were collected from controlled breeding seasons initiated with estrous synchronization and AI targeting heifers to calve by 24 mo of age. The BovineSNP50 BeadChip was used to ascertain 53,692 SNP genotypes for ∼802 heifers. Associations of genotypes and phenotypes were performed and SNP effects were estimated for each trait. Minimally associated SNP (P < 0.05) and their effects across the 10 traits formed the basis for an association weight matrix and its derived gene network related to FSC (57.3% success and heritability = 0.06 ± 0.05). These analyses yielded 1,555 important SNP, which inferred genes linked by 113,873 correlations within a network. Specifically, 1,386 SNP were nodes and the 5,132 strongest correlations (|r| ≥ 0.90) were edges. The network was filtered with genes queried from a transcriptome resource created from deep sequencing of RNA (i.e., RNA-Seq) from the hypothalamus of a prepubertal and a postpubertal Brangus heifer. The remaining hypothalamic-influenced network contained 978 genes connected by 2,560 edges or predicted gene interactions. This hypothalamic gene network was enriched with genes involved in axon guidance, which is a pathway known to influence pulsatile release of LHRH. There were 5 transcription factors with 21 or more connections: ZMAT3, STAT6, RFX4, PLAGL1, and NR6A1 for FSC. The SNP that identified these genes were intragenic and were on chromosomes 1, 5, 9, and 11. Chromosome 5 harbored both STAT6 and RFX4. The large number of interactions and genes observed with network analyses of multiple sources of genomic data (i.e., GWAS and RNA-Seq) support the concept of FSC being a polygenic trait.

The aim of this study was to identify the presence of SNPs in the chemokine genes CCL2 and IL8 and the chemokine receptor genes IL8RA and CCR2, and assess their potential contribution to variation in estimated breeding values (EBVs) for somatic cell score (SCS) and four other traits in Canadian Holstein bulls. Pools of DNA for bulls with high (H) and low (L) EBVs for SCS were used for identification of 11 SNPs. Two unreported SNPs were found in the CCL2 gene and one SNP was found in the CCR2 gene. Previously reported SNPs (three in the IL8 gene and five in the IL8RA chemokine receptor) were also identified. Two SNPs in CCL2, three in IL8, one in IL8RA and one in CCR2 were genotyped in Canadian Holstein bulls (n = 338) using tetra primer ARMS-PCR. We investigated associations of these seven polymorphisms with three production traits (milk yield, fat yield and protein yield) and one conformation trait related to mastitis (udder depth). The allele substitution effect for the CCL2 rs41255713:T>C SNP was significant at an experimental-wise level for milk yield (247.5 +/- 79.9 kg) and protein yield (7.4 +/- 2.3 kg) EBVs (P <or= 0.05). The associations of the SNPs with SCS EBVs were not significant at an experimental-wise level. However, the allele substitution effect of the CCR2 rs41257559:C>T SNP on SCS was significant at the comparison-wise level (-0.04 +/- 0.02, P = 0.05), which might indicate a possible association in support of other published studies. Lastly, we assigned CCR2 to BTA22q24, where a previously QTL for SCS was identified.

ABSTRACT Major histocompatibility complex (MHC) class II genes are cell surface molecules with roles in intercellular recognition, discrimination between self and non-self and humoral and cell-mediated immune responses. We amplified a 228-bp fragment of exon 2 of MHC DQB1 gene in 60 animals made up of the three major Nigerian goat breeds [West African Dwarf (WAD), Red Sokoto (RS) and Sahel (SH)]. Comparison of predicted amino acid residues of Nigerian goats with similar alleles from other ruminants revealed considerable similarity in amino acid substitution pattern. Twenty polymorphic positions were identified, four of which are located in the peptide binding region of goat DQB1 locus. However, seven of the amino acid substitutions were peculiar to Nigerian goats compared to published caprine sequences. A significantly (P<0.01) higher rate of non-synonymous substitutions per non-synonymous site (dN) than synonymous substitutions per synonymous site (dS) at the DQB1 locus suggests that allelic sequence evolution at this locus may be driven by balancing selection. In-silico functional analysis of non-synonymous mutations obtained using PANTHER revealed that three of the amino acid substitutions at the peptide binding region (Y27S, T29N and D57T) did not impair protein function. Based on neighbor-joining phylogenetic tree (UPGMA) derived from consensus sequences, the northern SH and RS goats are closer at this locus compared to the southern WAD goats. Our results provide the first description of Nigerian goat DQB1 sequence polymorphism; information that might be used in the search of association with disease resistance. Key words: MHC Class II genes, DQB1, Exon 2, Polymorphisms, Nigerian, Goats

ABSTRACT The major histocompatibility complex (MHC) genes are associated with genetic resistance and susceptibility to diseases. The MHC class III is very gene dense and contains genes of many types including the complement, heat stress protein and cytokine family genes. We carried out a study to identify single nucleotide polymorphisms (SNPs) in ovine APOM, BAT2 and G6B genes in Nigerian sheep and elucidated their phylogenetic relationships in ten mammalian species. The highest mutation rate of 11 SNPs was observed in G6B gene (3 synonymous and 8 non-synonymous mutations) followed by 10 mutations in BAT2 (1 synonymous and 9 non synonymous mutations) while APOM gene showed the least mutation rate (2 synonymous and 5 non-synonymous mutations). A phylogenetic analysis to compare the sequences in 10 mammalian species (sheep, cattle, pig, monkey, gorilla, giant panda, elephant, rabbit, dog and chimpanzee) was carried out. Our study revealed a lowest average nucleotide substitution per site (Dxy) between sheep and cattle in APOM gene. The higher Dxy values were found between rabbit and dog (4.172), panda and chimpanzee (2.866) and chimpanzee and dog (4.692) indicating small genetic distances. BAT2 gene had the highest Dxy between cattle and chimpanzee (0.094) and rabbit and dog (0.070) which indicated even smaller genetic distances. Sheep and giant panda (12.047) had the highest Dxy in G6B gene. Prediction of protein structures showed that APOM gene consists mainly of beta strands while BAT2 and G6B are mixed structure proteins, consisting of alpha helix, beta strands and random coils. The proteins do not share any similar domain features despite the close proximity of these genes on ovine chromosome 20.

This study was conducted to evaluate the variation in antibody from Newcastle disease (ND) vaccinated breeder birds and their progenies. The chicks were evaluated for maternally derived antibody (MDA) against ND virus and also the MDA transfer rate for each genotype. The local parent stocks were Frizzle-feathered, Normal-feathered, and Naked neck while an exotic parent stock (Anak Titan) was used for the purpose of comparison. Sera samples were collected from chicks generated at day 3 post-hatch, and sera were also collected from the parent stocks. The sera samples were stored at -20 °C until analysed. Enzyme linked immuno-sorbent assay (ELISA) test was used for the detection and quantification of antibodies to ND in the parent stocks and the chicks using IDEXX Newcastle Disease ELISA test kit. The least squares means of antibody titers for parent stocks were 413.333 ± 68.853, 426.333 ± 121.949, 481.667 ± 145.454, and 1148.333 ± 532.843 for Frizzle-feathered, Normal-feathered, Naked Neck, and Anak Titan, and the calculated MDA transfer rate was 96.4, 93.8, 88.7, and 34.7 % for Frizzle-feathered, Normal-feathered, Naked neck, and Anak Titan, respectively. The mean antibody titers for chicks were 398.6 ± 43.871, 400.0 ± 53.952, 427.0 ± 89.353, and 398.8 ± 57.593 for Frizzle-feathered, Normal-feathered, Naked neck, and Anak Titan, respectively. The antibody titers from parent stocks were higher than those observed in chicks for all the genotypes. The values obtained in this study indicated that parent stocks with their progenies were below protective level. The local parent stocks had higher transfer rate when compared to their exotic counterpart. Hence, there is an indication from this finding that the local chickens had a better transfer rate in relation to Anak Titan which is an exotic breed. Therefore, there is the presence of genetic variability for antibody transfer in the Nigerian local chickens and can be incorporated in designing a breeding program for better adaptive potential.

Coat colour contributes to physiological adaptation in mammals and mediates response to thermal stress. Twenty-four adult West African Dwarf sheep of both sexes and with different coat colour types were used in this study. We measured rectal temperature (RT), respiratory rate (RR) and pulse rate (PR) before sunrise and sunset during the late dry season (January-March) and early rainy season (April-June) as well as packed cell volume (PCV), red blood cell (RBC) count, white blood cell (WBC) count, plasma sodium (Na(+)) and potassium (K(+)). Animals with black coat colour had the highest (P < 0.05) mean values of 38.92 ± 0.03 °C, 65.09 ± 1.06 breaths/min, 81.35 ± 0.78 beats/min, 1.70 ± 0.01 for RT, RR, PR and heat stress index (HSI), respectively, followed by brown mouflon and brown with extensive white, while the Badger Face coloured sheep had the least mean values. There were significant (P < 0.05) differences between male and female sheep for RT, RR, PR and HSI. Season had a significant (P < 0.05) effect on RT, RR, PR and HSI. Coat colour and sex also significantly (P < 0.01) affected RBC, WBC, Na(+) and K(+). Seasonal variation (P < 0.05) in all the blood parameters was observed, with the exception of PCV. Interaction effect of coat colour and sex was significant (P < 0.05) on RT and HSI. Correlation coefficients among the measured traits ranged from positive to negative values. These results indicate that selection of white-coloured sheep to attenuate heat stress is desirable in the hot humid tropics.

... b & Michael O. Ozoje a Available online: 24 Oct 2011. ... Veterinary Parasitology , 141: 291–301. [CrossRef], [PubMed], [Web of Science ®] View all references; Fakae et al. 200411. Fakae, BB, Musongong, GA, Chiejina, SN, Behnke, JM, Ngongeh, LA and Wakelin, D. 2004. ...