Search

The water buffalo is a fundamental resource, especially in developing countries, however, differently from other species, its genetic potential is still poorly investigated. In this work, we performed a candidate gene association study for milk composition in 491 female buffaloes. Animals were from four farms located in Southern Italy, where the Out-of-Breeding-Season-Mating technique is usually performed. We analysed three genes: (1) the signal transducer and activator of transcription 5A (STAT5A), (2) the tumour necrosis factor alpha (TNFα) and (3) the melatonin receptor 1A (MTNR1A). We confirmed the mutation at the MTNR1A gene and we found five novel single nucleotide polymorphisms (SNPs): one in the TNFα and four in the STAT5A. No associations were found for the SNPs in the MTNR1A and TNFα genes, while we identified a marked association with milk protein % for a C > T substitution at the STAT5A gene. At this locus, the TT buffaloes showed significantly higher protein percentage in milk. Conversely, this genotype class was the less frequent in the population. Moreover, an A > G substitution at the STAT5A showed an influence on reproductive seasonality, with the advantageous allele most frequent in the population, suggesting a possible effect of selection for this trait. The C > T substitution on STAT5A detected in present study could be used in marker assisted selection of Mediterranean Italian buffalo, and should be monitored to understand the reasons behind the low frequency of the favourable genotype at this locus and to stop this unfavourable trend in the population.

The SLC24A5 (Solute Carrier family 24, member 5) gene is implicated in skin pigmentation in zebrafish and humans as it regulates the morphogenesis of melanosomes, specialized lysosomes involved in melanin deposit. In humans, the ancestral allele predominates in African and East Asian populations, while the allelic variant is nearly fixed in European populations and correlates with lighter pigmentation. Considering the role of melanin in the protecting of DNA from ultraviolet radiation, the lack of information in cattle and the importance of polymorphisms associated with pigmentation phenotypes, we investigated the SLC24A5 gene in cattle with light and dark skin pigmentation. To identify SNPs (Single Nucleotide Polymorphisms) in this gene and their association to dark skin pigmentation in cattle, each of the nine SLC24A5 exons, three introns (1, 3 and 8) and a portion of intron 5, were sequenced in a set of sixteen animals belonging to four Italian cattle breeds, two African zebu breeds and two African sanga breeds. The region spanning exons 3 and 4 was sequenced in fifteen animals belonging to seven additional breeds. A total of sixteen SNPs were identified: eleven positioned in introns (six in intron 1, one in intron 5 and four in intron 8) and five in exons (one in exon 1, two in exon 6 and two in exon 7). Three SNPs (located in exons 1, 6 and 7) were non synonymous, determining Pro19Leu, Ala238Val, and Met341Ile amino acid changes, respectively. All the SNPs identified were polymorphic between Bos taurus, Bos indicus and Sanga, while none of them resulted associated with the studied phenotype and discriminated the three breeds (Chianina, Mucubal and Goudali) characterized by dark pigmented skin from the others.

Aim of this research was to identify a panel of SNPs in coat colour genes useful for breed traceability in Rendena, an autochthonous cattle breed raised in the province of Trento, and other 4 Italian cattle breeds. First, we sequenced some regions of several coat colour genes in 10 animals belonging to 5 breeds characterised by different coat colour phenotypes (Rendena, Italian Brown, Grey Alpine, Italian Friesian, and Italian Red Pied), and we detected 21 SNPs in 13 genes. These markers and 6 additional SNPs were used to genotype 180 animals of the same 5 breeds obtaining useful genotyping data for a total of 22 SNPs in 13 genes. Five out of the 22 SNP markers in the MC1R, KIT, MLPH, and SILV genes had the highest discriminating power. The panel of 22 SNPs is useful to trace Rendena particularly from Red Italian Pied and Italian Friesian.

We presented the preliminary results of the analysis of semen phenotypic and quality data provided by ANARB along with the result of SNPs discovery on seven candidate genes for male fertility and the ongoing study on mtDNA. The phenotypic data recorded by Computer Assisted Sperm Analyzer of fresh semen for 1,014 bulls were evaluated. The least squared means of volumes were lower than data in literature generally referred to mature bulls, whereas the spermatozoa concentrations, total and progressive motility were satisfactory. As expected in young bulls, the percentage of spermatozoa morphological abnormalities was high. The SNPs discovery in seven candidate genes revealed 30 new SNPs and confirmed the polymorphism in STAT5A gene. The complete sequencing of mtDNA of 48 extreme bulls for semen phenotypic traits revealed 274 mutations. Association between SNPs and semen phenotypes is on going. Our results represent a preliminary step towards the sounding of genetic mechanisms of bull fertility and highlight the paramount importance of reliable phenotypes for association studies.

The water buffalo is a fundamental resource, especially in developing countries, however, differently from other species, its genetic potential is still poorly investigated. In this work, we performed a candidate gene association study for milk composition in 491 female buffaloes. Animals were from four farms located in Southern Italy, where the Out-of-Breeding-Season-Mating technique is usually performed. We analysed three genes: (1) the signal transducer and activator of transcription 5A (STAT5A), (2) the tumour necrosis factor alpha (TNFα) and (3) the melatonin receptor 1A (MTNR1A). We confirmed the mutation at theMTNR1Agene and we found five novel single nucleotide polymorphisms (SNPs): one in theTNFαand four in theSTAT5A. No associations were found for the SNPs in theMTNR1AandTNFαgenes, while we identified a marked association with milk protein % for a C > T substitution at theSTAT5Agene. At thislocus, the TT buffaloes showed significantly higher protein percentage in milk. Conversely, this genotype class was the less frequent in the population. Moreover, an A > G substitution at theSTAT5Ashowed an influence on reproductive seasonality, with the advantageous allele most frequent in the population, suggesting a possible effect of selection for this trait. The C > T substitution onSTAT5Adetected in present study could be used in marker assisted selection of Mediterranean Italian buffalo, and should be monitored to understand the reasons behind the low frequency of the favourable genotype at thislocusand to stop this unfavourable trend in the population. [ABSTRACT FROM PUBLISHER]