RESUMEN
The transition period is a critical time for dairy cows as the animal is subjected to the physiological stress accompanying parturition. Immunosuppression and health status were examined during this period in 80 Holstein cows. Blood samples were taken from each cow 3, 2 and 1 week before and after calving, and at calving (0 day). RNA was extracted and subjected to real-time PCR to determine mRNA levels for the immune-related genes TLR 2, 4, 6, 7 and ß-defensin 5 in addition to the reproduction-related genes prolactin and IGF-I. Results showed significant up-regulation of pro-inflammatory-selected genes, TLR 4, 6 7 and ß-defensin 5 at the third-week post-calving; however, earlier periods had lower expression of such genes. In contrast, the immunosuppression biomarker TLR2 gene was up-regulated at calving and 1 week after parturition and then down-regulated again at second and third week. Prolactin and IGF-I genes expression levels were significantly and gradually increased mainly post-partum. This research highlights that the expression patterns of TLRs, BNBD5, PRL and IGF-I could be biomarkers to follow up immune and reproductive status of dairy cow at peri-parturient period to predict the most susceptible risk time for disease incidence and to build up management protocol.
Asunto(s)
Bovinos/fisiología , Periodo Periparto/fisiología , Transcriptoma/fisiología , Animales , Biomarcadores , Bovinos/inmunología , Bovinos/metabolismo , Femenino , Terapia de Inmunosupresión/veterinaria , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Periodo Periparto/inmunología , Periodo Periparto/metabolismo , Prolactina/genética , Prolactina/metabolismo , ARN Mensajero , Estrés Fisiológico/fisiología , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , beta-Defensinas/genética , beta-Defensinas/metabolismoRESUMEN
OBJECTIVE: The GH and MSTN gene polymorphisms and their association with body weight were declared in a population of 100 Friesian bull calves. MATERIALS AND METHODS: For DNA extraction, collection of blood samples was carried out from the studied animals. The PCR for GH and MSTN genes yielded fragments of 329 and 1346 bp, respectively. RESULTS: The PCR-HpaII digestion of 329 bp of GH gene revealed three genotypes: AA genotype possess undigested fragment (329 bp), AB genotype has three fragments (329, 224 and 105 bp) and BB genotype has two fragments (224 and 105 bp). The GH genotypes incidence and alleles frequency were calculated. For the 100 Friesian bull calves, genotypic frequencies for the AA, AB and BB genotypes were 0.1, 0.78 and 0.12, respectively and the allele frequencies for A and B allele frequencies were 0.49 and 0.51. Statistical analysis revealed that there was a significant effect of GH genotypes on body weight. The AB genotype possessed higher body weight than the other 2 genotypes. Regarding MSTN gene, PCR-DraI digestion of 1346 bp fragment was monomorphic; where it yielded four fragments (505, 427, 321 and 93 bp) in all animals under study. CONCLUSION: The outcome of this study is that it highlights the effectiveness of GH/HpaII locus as candidate marker for body weight in cattle rather than MSTN/DraI.