ABSTRACT
A melatonin receptor 1A (MTNR1A) gene polymorphism in adult buffaloes has been reported to affect reproductive seasonality. Consequently, the aim of the present study was to assess whether this polymorphism can affect age at first conception and the interval between first and second calving in Mediterranean Italian buffaloes. The allelic frequency of the C and T alleles was 0.44 and 0.56, respectively, whereas the genotypic frequency was 26% for C/C, 40% for C/T and 34% for T/T. The average age at first mating was approximately 20 months, whereas that at calving was approximately 32 months. The largest number of calvings of primiparous buffaloes was recorded between June and October. No associations between genotype, first mating and subsequent calving date were found. The duration from first to second calving was longer in buffaloes with the C/C genotype compared with those with the T/T and C/T genotypes (P<0.01). The period of calving for buffaloes with the C/C genotype was mainly from July to September, whereas that for buffaloes with the T/T genotype was largely from March to May. The MTNR1A gene had no effect on the age of first conception in Mediterranean Italian buffaloes. Rather, the association between the T/T genotype and reproductive activity during days with a long photoperiod indicates that this polymorphism may be considered a genetic marker to identify buffaloes that are able to reproduce out of the breeding season.
Subject(s)
Buffaloes/genetics , Polymorphism, Genetic , Receptor, Melatonin, MT1/genetics , Reproduction/genetics , Age Factors , Animals , Female , Gene Frequency , Genotype , Italy , Male , Parity/genetics , Phenotype , Photoperiod , Pregnancy , Seasons , Sexual Behavior, AnimalABSTRACT
The aim of this study was to examine the polymorphism in MTNR1A gene and its relation to reproductive seasonality in Mediterranean Italian buffaloes reared in Sardinia. The mating period and calving of 100 multiparous buffalo-cows were recorded for three years (2005-2008). Genomic DNA was subjected to PCR for the amplification of the exon II, then 40 amplicons were sequenced. The obtained sequence was deposited in GeneBank database (accession number GU817415). PCR products were checked for the presence of HpaI restriction sites and assigned to genotypes "C/C", "C/T" or "T/T". Allelic frequency of C and T alleles was 0.44 and 0.56 and genotypic frequency was 26% for genotype C/C, 40% for C/T and 34% for T/T. In the three observed years the animals with C/C genotype showed the highest number of mating in the semester between August and January and their calving mainly occurred from August to September. On the other hand animals with T/T genotype showed mating mostly in the semester between February and July and calving occurred largely from March to May in all the three years. Heterozygous, in all the three years, showed about the same number of animals mated within each six-month period. The results of the present study provide for the first time a partial sequence as well as one polymorphic site of the MTNR1A receptor gene from buffaloes. Moreover our data showed an association between Single Nucleotide Polymorphism and seasonal reproductive activity in these animals.
Subject(s)
Buffaloes/genetics , Polymorphism, Genetic , Receptor, Melatonin, MT1/genetics , Seasons , Sexual Behavior, Animal , Animals , Base Sequence , Buffaloes/metabolism , Buffaloes/physiology , Genotype , Molecular Sequence Data , Receptor, Melatonin, MT1/chemistry , Receptor, Melatonin, MT1/metabolism , Sequence AlignmentABSTRACT
In the present study, the initial developmental stage of Toxocara canis eggs and larvae, and number of recovered larvae from BALB/c mouse-infected organs are described. In vitro culture of T. canis detects the frequencies of interphasic, mitotic and embryonated eggs only within a 7-day period. Analysis by egg counting was carried out for 32 days. The results showed that at 7 days after cultivation, the frequency of larvae was 50.4% and that this frequency reached 52.8% in 32 days. In the experimental infection of BALB/c mice with T. canis, the number of recovered larvae statistically increased in the brain and liver, with doses of approximately 200 and 1000 eggs. After 7 days of infection, a larger number of larvae were obtained in the lung and liver, although a maximum amount was found in the brain after a 15- or 30-day post-infection period.
Subject(s)
Toxocara canis/growth & development , Toxocariasis/parasitology , Animals , Brain/parasitology , Disease Models, Animal , Female , Larva/growth & development , Liver/parasitology , Lung/parasitology , Male , Mice , Mice, Inbred BALB C , Parasite Egg Count , Time FactorsABSTRACT
In the present study, the initial developmental stage of Toxocara canis eggs and larvae, and number of recovered larvae from BALB/c mouse-infected organs are described. In vitro culture of T. canis detects the frequencies of interphasic, mitotic and embryonated eggs only within a 7-day period. Analysis by egg counting was carried out for 32 days. The results showed that at 7 days after cultivation, the frequency of larvae was 50.4% and that this frequency reached 52.8% in 32 days. In the experimental infection of BALB/c mice with T. canis, the number of recovered larvae statistically increased in the brain and liver, with doses of approximately 200 and 1000 eggs. After 7 days of infection, a larger number of larvae were obtained in the lung and liver, although a maximum amount was found in the brain after a 15- or 30-day post-infection period.
