Polymorphisms of the melatonin receptor 1A (MTNR1A) gene do not affect sexual activity, plasma testosterone concentrations or testicular characteristics of 8-month-old ram-lambs born in autumn
José-Alfonso Abecia, Adriana Casao, Francisco Canto, Maria Consuelo Mura, Sebastiano Luridiana, Melissa Carvajal-Serna, Rosaura Pérez-Pe, Vincenzo Carcangiu
Thirty-nine autumn-born ram-lambs were used to study whether polymorphisms of the melatonin receptor 1A (MTNR1A) gene influence some reproductive parameters of Oct-born ram-lambs at 8 months of age. Animals were genotyped for their RsaI (CC, n=24; CT, n=6; TT, n=9) and MnlI (GG, n=27; GA, n=6; AA, n=6) allelic variants of the MTNR1A gene. Liveweight (LW) was recorded bi-weekly until Jun, and scrotal perimeter (SP) was recorded once per month. From mid-Jan, blood samples were collected weekly to measure plasma testosterone concentrations. In mid-Jun, individual serving-capacity tests were performed. Testicular ultrasonography was performed at the end of the experiment. The effects of the week and gene polymorphism on LW, scrotal perimeter, and plasma testosterone concentrations were evaluated statistically by the GLM for repeated measures procedure. LW, SP, and plasma testosterone concentrations were significantly (P<0.001) affected by week, but neither of the polymorphisms of the melatonin receptor 1A (MTNR1A) gene affected these variables. In the serving tests, genotypes did not differ significantly in individual behaviors or the number of events (CC: 24.1±3.2, CT: 26.3±13.0, TT: 16.8±4.8, GG: 22.0±3.0, GA: 21.0±6.7, AA: 27.8±12.7). Testicular features assessed by ultrasonography did not differ significantly among genotypes. In conclusion, the polymorphisms of the melatonin receptor 1A (MTNR1A) gene did not have an effect on the reproductive characteristics of autumn-born ram lambs, based on serving capacity tests, testosterone secretion, and testicular measurements at 8 months of age.
Abecia JA, Heredia A, Pérez-Pe R, Casao A, Carcangiu V, Mura MC, Miranda de la Lama G (2022) Polymorphisms of the melatonin receptor 1A (MTNR1A) gene affect the sexual performance of Rasa Aragonesa rams without changing their social dominance. J Anim Behav Biometeorol 10:2231.
Abecia JA, Mura MC, Carvajal-Serna M, Pulinas L, Macías A, Casao A, Pérez-Pe R, Carcangiu V (2020) Polymorphisms of the melatonin receptor 1A (MTNR1A) gene influence the age at first mating in autumn-born ram-lambs and sexual activity of adult rams in spring. Theriogenology 157:42-47.
Andrade AKG, Soares AT, Freitas FF, Silva SV, Peña-Alfaro CE, Batista AM, Guerra MMP (2014) Testicular and epididymal ultrasonography in Santa Inês lambs raised in Brazil. Anim Reprod 11:110-118.
Calderón-Leyva G, Meza-Herrera CA, Rodriguez-Martinez R, Angel-García O, Rivas-Muñoz R, Delgado-Bermejo JV, Véliz-Deras FG (2018) Influence of sexual behavior of Dorper rams treated with glutamate and/or testosterone on reproductive performance of anovulatory ewes. Theriogenology 106:79-86.
Carcangiu V, Mura MC, Vacca GM, Pazzola M, Dettori ML, Luridiana S, Bini PP (2009) Polymorphism of the melatonin receptor MT1 gene and its relationship with seasonal reproductive activity in the Sarda sheep breed. Anim Reprod Sci 116:65e72.
Courot M, de Reviers MM, Pelletier J (1975) Variation in pituitary and blood LH during puberty in the male lamb Relation to time of birth. Annls Biol Anim Biochim Biophys 15:509-516.
Damián JP, Beracochea F, Hötzel MJ, Banchero G, Ungerfeld R (2015) Reproductive and sexual behaviour development of dam or artificially reared male lambs. Physiol Behav 47:47–53.
Dardente H (2012) Melatonin-dependent timing of seasonal reproduction by the pars tuberalis: pivotal roles for long daylengths and thyroid hormones. J Neuroendocrinol 24:249e66.
Dyrmundsson OR (1973a) Puberty and early reproductive performance in sheep. I. Ewe lambs. Anim Breed Abst Al:273-289.
Drymundsson OR (1973b) Puberty and early reproductive performance in sheep. II. Ram lambs. Anim Breed Abstr Al:419-30.
Dubocovich ML, Yun K, Al-Ghoul WM, Benloucif S, Masana MI (1998) Selective MT2 Melatonin receptor antagonists block melatonin-mediated phase advances of circadian rhythms. FASEB J 12:1211e20.
Forcada F, Zarazaga L, Abecia JA (1995) Effect of exogenous melatonin and plane of nutrition after weaning on estrous activity, endocrine status and ovulation rate in Salz ewes lambing in the seasonal anestrus. Theriogenology 43:1179-1193.
Foster DL (1974) Regulation of gonadotrophins during fetal development in the sheep. In: Sexual endocrinology of the perinatal period, INSERM, Paris, France, Vol 32, pp. 143-115.
Foster DL, Hileman SM (2015) Puberty in the sheep. In: Knobil and Neill's Physiology of Reproduction (Plant T.M., Zeleznik A.J. eds.), Elsevier, Amsterdam, The Netherlands, pp. 1441-1485.
Haldar A, French MC, Brauning R, Edwards SJ, O'Connell AR, Farquhar PA, Davis GH, Johnstone PD, Juengel JL (2014) Single-nucleotide polymorphisms in the LEPR gene are associated with divergent phenotypes for age at onset of puberty in Davisdale ewes. Biol Reprod 20:33.
Hochereau-de Reviers MT, Copin M, Seck M, Monet-Kuntz M, Cornu C, Fontaine C, Perreau C, Elsen JM, Boomarov O (1990) Stimulation of testosterone production by PMSG injection in the ovine male: Effect of breed and age and application to males carrying or not carrying the F Booroola gene. Anim Reprod Sci 23:21–32.
Khalifa EI, Ahmed ME, Hafez YJ, El-Zolaky OA, Bahera KM, Abido AA (2013) Age at puberty and fertility of Rahmani sheep fed on biological inoculated corn silage. Ann Agric ScI 58:163–172.
Kilgour RJ, Whale RG (1980) The relation between mating activity of rams in pens and subsequent flock mating performance. Aust J Exp Agri 20:5–8.
Luridiana S, Mura MC, Daga C, Cosso G, Bodano S, Farci F, Zidda F, Carcangiu V (2016). Influences of melatonin treatment, melatonin receptor 1A (MTNR1A) and kisspeptin (KiSS-1) gene polymorphisms on first conception in Sarda ewe lambs. Reprod Fertil Dev 28:750-756.
Messer LA, Wang L, Tuggle CK, Yerle M, Chardon P, Pomp D, Womack JE, Barendse W, Crawford AM, Notter DR, Rothschild MF (1997) Mapping of the melatonin receptor 1a (MTNR1A) gene in pigs, sheep and cattle. Mamm Genome 8:368e70.
Mura MC, Luridiana S, Pulinas L, Di Stefano MV, Carcangiu V (2019) Reproductive response to male joining with ewes with different allelic variants of the MTNR1A gene. Anim Reprod Sci 200:67e74.
Mura MC, Luridiana S, Vacca GM, Bini PP, Carcangiu V (2010) Effect of genotype at the MTNR1A locus and melatonin treatment on first conception in Sarda ewe lambs. Theriogenology 4:1579-1586.
Paludo M, Mura MC, Luridiana S, Pazzola M, Daga C, Vacca GM, Bua S, Bodano S, Sanna GA, Carcangiu V (2011) Genotype of melatonin receptor mt1 (MTNR1A) and puberty in mediterranean italian buffalo. Agric Conspec Sci 76:157-160.
Pelletier J, Bodin L, Hanocq E, Malpaux B, Teyssier J, Thimonier J, Chemineau P (2000) Association between expression of reproductive seasonality and alleles of the gene Mel1a receptor in the ewe. Biol Reprod 62:1096e101.
Reppert SM, Weaver DR, Ebisawa T (1994) Cloning and characterization of a mammalian melatonin receptor that mediates reproductive and circadian responses. Neuron 13:1177e85.
Rosales Nieto CA, Ferguson MB, Macleay CA, Briegel JR, Martin GB, Thompson AN (2013) Selection for superior growth advances the onset of puberty and increases reproductive performance in ewe lambs. Animal 7:990-997.
Sliwowska J, Billings HJ, Goodman RL, Coolen LM, Lehman MN (2004) The premammillary hypothalamic area of the Ewe: anatomical characterization of a melatonin target area mediating seasonal reproduction. Biol Reprod 70:1768e75.
Ungerfeld R, Lacuesta L (2010) Social rank during pre-pubertal development and reproductive performance of adult rams. Anim Reprod Sci 1:101-105.
Valasi I, Fthenakis GC, Prassinos NN, Menegatos I, Grigoropoulou V, Deligiannis C, Vainas E, Amiridis GS (2009) Onset of pubertyand growth are not affected by repeated follicular aspiration inwinter- or autumn-born lambs. Small Rumin Res 84:35–40.
Weaver DR, Liu C, Reppert SM (1996) Nature's knock-out: the Mel1b receptor is not necessary for reproductive and circadian responses to melatonin in Siberian hamsters. Mol Endocrinol 10:1478e87.
Wheaton JE, Godfrey RW (2003) Plasma LH, FSH, testosterone, and age at puberty in ram lambs actively immunized against an inhibin a-subunit peptide. Theriogenology 60:933-941.
Xing F, Zhang C, Kong Z (2019) Cloning and expression of lin-28 homolog B gene in the onset of puberty in Duolang sheep. Asian-Australas J Anim Sci 32:23-30.
Yarney TA, Sanford LM (1993) Pubertal development of ram lambs: Physical and endocrinological traits in combination as indices of postpubertal reproductive function. Theriogenology 40:735-744.
Yarney TA, Sanford LM, Palmer WM (1990) Pubertal development of ram lambs: body weight and testicular size measurements as indices of postpubertal reproductive function. Can J Anim Sci 70:139-147.