The Effect of Parity of the Dam on Sexual Maturation, Serum Concentrations of Metabolic Hormones and the Response to Luteinizing Hormone Releasing Hormone in Bull Calves

Nutrigenomics and its role in male puberty of cattle: a mini review

Nutrigenomics a novel era in genomics research is based on puzzling issue on how nutrition and genes re-interacts. Perusal of literature reveals that very few information are available in this field and especially when it is associated with puberty in cattle which is a multigenic trait of great economic importance. Thus it opens a new area of research interest. Various markers like-gonadotropin releasing hormone/GNRH (responsible for sexual differentiation and reproduction), interstitial growth regulating factor/IGF1 (having signal controlling reproduction function linked to somatic growth); circulating metabolic hormones viz., leptin apart from GnRH and IGF1 (having impact on testicular development in peripubertal bull) are proved to be associated with male puberty in cattle. Various minerals (copper, selenium, manganese, zinc, chromium, iron and molybdenum) and vitamins (Vit. A, D, E and C) are directly or indirectly linked to male puberty. But no research till today initiated how the nutrients effect on the transcriptome/proteome/metabolome level of marker genes associated with male puberty in cattle. Application of nanotechnology to make food safer for promotion of good health has created much excitement and nanoparticles has been developed against infectious diseases (e.g., Campylobacteriosis) affecting puberty along with certain nanocarriers that can facilitate the uptake of essential nutrients associated with puberty. Much of nutrigenomics research is however in infancy and hence the present mini-review will allow building the concept among researchers and scientists to initiate research in this interesting area.

Association between GNRHR, LHR and IGF1 polymorphisms and timing of puberty in male Angus cattle

Background

In bovines, there are significant differences within and among beef breeds in the time when bulls reach puberty. Although the timing of puberty is likely to be a multigenic trait, previous studies indicate that there may also be single genes that exert major effects on the timing of puberty within the general population. Despite its economic importance, there are not many SNPs or genetic markers associated with the age of puberty in male cattle. In the present work, we selected three candidate genes, GNRHR, LHR and IGF1, and associated their polymorphisms with the age of puberty in Angus male cattle.

Results

After weaning, 276 Angus males were measured every month for weight (W), scrotal circumference (SC), sperm concentration (C) and percentage of motility (M). A total of 4 SNPs, two within GNRHR, one in LHR and one in IGF1 were genotyped using the pyrosequencing technique. IGF1-SnaBI SNP was significant associated (P < 0.01) with age at SC 28 cm, but it were not associated with age at M 10% and C 50 million. Genotype CC exhibited an average age at SC 28 cm of 7 and 11 days higher than CT (p = 0.037) and TT (p = 0.012), respectively. This SNP explained 1.5% of the genetic variance of age of puberty at SC28. LHR-I499L, GNRHR-SNP5 and GNRHR-SNP6 were not associated with any of the measurements. However, GNRHR haplotypes showed a suggestive association with age at SC 28 cm.

Conclusions

The findings presented here could support the hypothesis that IGF1 is a regulator of the arrival to puberty in male calves and is involved in the events that precede and initiate puberty in bull calves. Given that most studies in cattle, as well as in other mammals, were done in female, the present results are the first evidence of markers associated with age at puberty in male cattle.