The aim was to assess the influence of MTNR1A polymorphism on the fertility rate after AI (artificial insemination) in late spring in Sarda sheep breed. From six farms, 480 adult ewes were chosen (80 heads in each farm). All these animals were 3 to 4 years old, were lactating and had a body condition score≥2.5. A blood sample was collected from each ewe for genomic DNA extraction to perform PCR analysis. In total 40 randomly chosen amplicons (an uniform 824bp product) were sequenced and aligned with the ovine MTNR1A sequence (GenBank accession number U14109). All the 480 PCR products were then subjected to restriction fragment length polymorphism (RFLP) analysis using MnlI endonuclease. The ewes were so genotyped and assigned to +/+, +/− or −/− genotypes, on the basis of the presence of an A (allele −) or a G (allele +) in position 328 of the PCR product. Allelic frequency was 0.77 for allele + and 0.23 for allele −. Genotype frequency was 0.68 for +/+ (326/480), 0.19 for +/− (90/480) and 0.13 for −/− (64/480). For each genotype 60 ewes were randomly chosen and divided into two groups, G1 and G2, each of 90 ewes (30 ewes for each genotype). On May 3 G1 was synchronized with intravaginal sponges containing 40 mg of Fluorogestone acetate for 14 days; G2 received the sponges on May 16 (2 weeks after G1). At sponges removal (on May 16 for G1; on May 29 for G2) the animal received intramuscularly 350 IU PMSG. After 54-56 hours from sponge removal the animals were inseminated with chilled semen (400x106 spermatozoa) at the entrance of the cervix. Pregnancy status was checked after 50 days from AI, by transabdominal ultrasonography. Lambing dates have been recorded from 21 to 22 weeks after AI. Pregnancy rate was higher in animals with the genotype +/+ compared to the others genotypes (P<0.01) both in G1 and G2. No statistical differences were found in the three genotypes about pregnancy rate between G1 and G2. Lambing rate was higher (P<0.01) in the +/+ animals compared to the other two genotypes both in G1 and G2. No statistical differences were found in lambing rate between G1 and G2. In conclusion genotype at MTNR1A has shown to have a positive influence on reproductive response to out of season synchronization and AI.
Effect of polymorphism at MTNR1A melatonin receptor gene on fertility in Sarda breed sheep subjected to artificial insemination in late spring / Mura, Maria Consuelo; Luridiana, Sebastiano; Daga, Cinzia; Paludo, M.; Vacca, Giuseppe Massimo; Carcangiu, Vincenzo; 25 28, Maggio; Belgrado, Serbia; 19, ; 58, 6. 3.. - 19:(2011), pp. 58-63. (Intervento presentato al convegno 19th International Congress of Mediterranean Federation of Health and Production of Ruminants tenutosi a Belgrade-Serbia nel May 25-28, 2011).
Effect of polymorphism at MTNR1A melatonin receptor gene on fertility in Sarda breed sheep subjected to artificial insemination in late spring
MURA, Maria Consuelo;LURIDIANA, Sebastiano;DAGA, Cinzia;VACCA, Giuseppe Massimo;CARCANGIU, Vincenzo;
2011-01-01
Abstract
The aim was to assess the influence of MTNR1A polymorphism on the fertility rate after AI (artificial insemination) in late spring in Sarda sheep breed. From six farms, 480 adult ewes were chosen (80 heads in each farm). All these animals were 3 to 4 years old, were lactating and had a body condition score≥2.5. A blood sample was collected from each ewe for genomic DNA extraction to perform PCR analysis. In total 40 randomly chosen amplicons (an uniform 824bp product) were sequenced and aligned with the ovine MTNR1A sequence (GenBank accession number U14109). All the 480 PCR products were then subjected to restriction fragment length polymorphism (RFLP) analysis using MnlI endonuclease. The ewes were so genotyped and assigned to +/+, +/− or −/− genotypes, on the basis of the presence of an A (allele −) or a G (allele +) in position 328 of the PCR product. Allelic frequency was 0.77 for allele + and 0.23 for allele −. Genotype frequency was 0.68 for +/+ (326/480), 0.19 for +/− (90/480) and 0.13 for −/− (64/480). For each genotype 60 ewes were randomly chosen and divided into two groups, G1 and G2, each of 90 ewes (30 ewes for each genotype). On May 3 G1 was synchronized with intravaginal sponges containing 40 mg of Fluorogestone acetate for 14 days; G2 received the sponges on May 16 (2 weeks after G1). At sponges removal (on May 16 for G1; on May 29 for G2) the animal received intramuscularly 350 IU PMSG. After 54-56 hours from sponge removal the animals were inseminated with chilled semen (400x106 spermatozoa) at the entrance of the cervix. Pregnancy status was checked after 50 days from AI, by transabdominal ultrasonography. Lambing dates have been recorded from 21 to 22 weeks after AI. Pregnancy rate was higher in animals with the genotype +/+ compared to the others genotypes (P<0.01) both in G1 and G2. No statistical differences were found in the three genotypes about pregnancy rate between G1 and G2. Lambing rate was higher (P<0.01) in the +/+ animals compared to the other two genotypes both in G1 and G2. No statistical differences were found in lambing rate between G1 and G2. In conclusion genotype at MTNR1A has shown to have a positive influence on reproductive response to out of season synchronization and AI.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.