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Item Análise multifatorial e preditores para características de importância econômica de matrizes suínas em granja multiplicadora(Universidade Federal de Goiás, 2021-09-30) Leal, Guilherme Brunno de Medeiros; Café, Marcos Barcellos; http://lattes.cnpq.br/9860968235125158; Antunes, Robson Carlos; http://lattes.cnpq.br/7590358205144485; Carmo, Adriana Santana do; http://lattes.cnpq.br/0782572407995106; Carmo, Adriana Santana do; Mascarenhas, Alessandra Gimenez; Cadavid, Verónica González; Leite, Carla Daniela Suguimoto; Masciol, Arthur dos SantosThe present work aimed to investigate the relationship between the productive characteristics and to identify the factors that affect the number of weaned piglets (NLD) per sow/year, the accumulated productivity in kilograms (kg) of weaned piglets (LD) per sow/year and the productive longevity of swine breeders in order to support the selection process of a breeding farm. In chapter 2, factor analyzes were performed in order to understand the relationship between the characteristics and multiple linear regression to identify the main predictor variables for the variables NLD per matrix/year and accumulated productivity in kg of LD per matrix/year. In chapter 3, the females were evaluated as to their longevity, according to two distinct stayability criteria, STAY1 and STAY2, which consider as longevity, respectively, the females that presented the number of live born piglets (NLNV) and kilogram of piglets weaned to the fourth parturition above the herd average. It was identified by the main latent factors that 55% variance between breeders on the farm is explained by the characteristics of maternal ability, piglet viability, fertility and perinatal mortality. The best regression models for prediction explained approximately 66% of the variation both for the NLD traits and for the total weight of weaned piglets adjusted for 21 days (PTD21), evidencing the characteristics number of stillborn piglets (NLNAT), number of dead piglets at birth (NLMN), mean piglet birth weight (PMN) and number of piglets weaned (NLD) with common explanatory factors. It was not possible to obtain a good predictive model for the characteristic mean weight of weaned piglets adjusted to 21 days (PD21) in the present study. The analysis of females by NLNV and PD21 categories indicated that sows that present NLNV below the herd average do not have the potential to exhibit an adequate accumulated production under the evaluated conditions of the farm. The best predictive models for female longevity by STAY1 criteria include age at first mating (IPC) and NLNV and for STAY2 it included only IPC. The prediction model proposed for STAY1 was more efficient (78%) than for STAY2 (55%). Selection for STAY1 can be performed with the NLNV of the first calving, while for STAY2 should preferably be performed later, by the accumulated NLD of the first three calvings. Survival analysis showed that by STAY1, females would be discarded later (8th parturition), when compared to STAY2 (6th parturition).Item Impacto da seleção de touros pelo mérito genético para fertilidade na eficiência reprodutiva de rebanhos Leiteiros(Universidade Federal de Goiás, 2020-02-04) Santos, Marcello Mamedes dos; Carmo, Adriana Santana do; http://lattes.cnpq.br/0782572407995106; Okada, Eliane Sayuri Miyagi; Peres, Rogerio Fonseca Guimaraes; Carmo, Adriana Santana doThe widespread use of artificial insemination favored that different genotypes were distributed in different regions around the world. The lack of adaptation to some environmental conditions can cause an effect called genotype x environment interaction, especially in polygenic traits, causing changes in animal performance. Thus, the objective of this study was to evaluate and validate the effect of daughter pregnancy rate (DPR) based sire selection on the fertility of the national herds, contributing to the good direction in the genetic improvement of Holstein cows. Reports about performance reproductive information were collected from six herds located in three different states. The properties were selected based on the following criteria: a) milk production in feedlot systems, b) at least 300 lactating cows, c) use of fixed time artificial insemination in female reproductive management and d) participation in the program of genetic improvement of the Holstein breed. Variance analysis was performed to assess the impact of different categories of DPR and CCR (cow conception rate) on the number of days open in the herd. All statistical analyses were performed using custom packages and scripts of the R program. Although the results are not statistically significant (P <0.05), the decrease in open days and the increase in conception rates have a favorable impact on the profitability of production systems. Pearson's correlation between the RPD and RCC groups is 88%, which shows that bulls with high RPD mostly have RCC of the same magnitude.Item Marcadores moleculares na identificação de corridas de homozigose e endogamia nas raças curraleiro pé-duro e pantaneiro(Universidade Federal de Goiás, 2021-11-25) Santos, Marcelo Fernandes dos; Magnabosco, Claudio Ulhoa; http://lattes.cnpq.br/1852112832119187; Rey, Fernando Sebastián Baldi; http://lattes.cnpq.br/2142265309634106; Carmo, Adriana Santana do; http://lattes.cnpq.br/0782572407995106; Carmo, Adriana Santana do; Freitas, Thais Miranda Silva; Leite, Carla Daniela SuguimotoThe runs of homozygosity (ROHs) can be used to estimate more accurate population parameters and genomic regions under selection in different species and breeds. Therefore, this approach can be used in locally adapted breeds to identify genes of economic interest and estimate autozygosity, enabling the optimization of selection and mating strategies and mitigating their extinction risk. The objective of this work is to identify and characterize the ROHs present in locally adapted breeds Curraleiro Pé-Duro (CPD) and Pantaneiro (PANT) in order to identify genes under selection and estimate their inbreeding coefficient (FROH). The ROHs were identified in 126 and 35 animals of the CPD and PANT breeds, respectively, with data from 54,000 SNP markers. For the identification of ROHs, the following criteria were used: a) sliding window of 50 SNPs, b) minimum number of 100 consecutive SNPs in each ROH, c) minimum length of 1 Mb, c) maximum interval between homozygous consecutive SNPs of 0, 5 Mb, d) maximum of five SNPs with absent genotypes, 1083 and 140 ROHs were found in the CPD and PANT breeds, respectively, and that the predominant pattern of ROHs in the studied breeds are those of medium to long size, which demonstrates recent events of autozygosity. Six islands of homozygosity were identified in both breeds on autosomal chromosomes 6, 8, 10, 13, 14 and 17. Genes and QTLs previously related to traits of interest are located in the segments found, highlighting QTLs associated with production and quality traits of milk (57%), as those involved in the content of proteins such as caseins and genes associated with the immune system, such as the genes of the beta defensin family. The estimated inbreeding coefficient showed that both breeds have low autozygosity (2-4%), which differs from what is expected for populations with a reduced genetic base such as those studied. The present work identified six homozygous islands in common in the Curraleiro Pé-Duro and Pantaneiro breeds, located in genomic regions previously reported to be associated with characteristics of economic interest, such as disease resistance and milk protein content, which can be considered candidate regions the selection. The inbreeding coefficient estimated based on the ROHs showed that inbreeding is low (2 to 4%) in the studied populations, diverging from what was expected in small populations.Item Identificação de assinaturas de seleção e variações no número de cópias em bovinos da raça Curraleiro Pé-Duro(Universidade Federal de Goiás, 2020-02-27) Teixeira, Ana Lúcia Coutinho; Mascioli, Arthur dos Santos; http://lattes.cnpq.br/6557055478323026; Carmo, Adriana Santana do; http://lattes.cnpq.br/0782572407995106; Carmo, Adriana Santana do; Hellmeister Filho, Paulo; Freitas, Thais Miranda SilvaThe use of new molecular technologies in animal production has grown significantly in recent years, as it allows us to understand the genetic architecture of the traits of interest. Thus, the present work aimed to identify the selection signatures and the copy number variations (CNVs) present in Curraleiro Pé-Duro (CPD), in order to identify genes related to the productive and adaptive capacity of this breed. For this purpose, Illumina® BovineHD BeadChip genotypes of 120 CPD cattle from 20 different properties were used. For selection signature detection, the quality control of SNPs was performed based on the SNP and sample call rate equal to or greater than 90% and SNPs with minor allelic frequency less than 3% using the software Plink. The construction of chromosomal haplotypes was performed using the Beagle software. Signatures were identified by the following methodologies: Haplotype Integration Score (iHS), Extended Haplotype Homozygosis (EHH) and Long Range Haplotype Test (LRH). The identification of CNVs was performed using PennCNV software, adjusting the Guanine and Cytosine (GC) content of a 500 base pair (bp) genomic window. Quality control was performed using LRR standard deviation less than 0.3, BAF standard deviation less than 0.01 and wave factor less than 0.05, samples with more than 150 CNVs and markers smaller than 5,000 bp has been removed. The identification of selection signatures proved to be effective in identifying genomic regions associated with production traits, and they are mainly related to adaptability, as they are related to thermotolerance and disease resistance. CNVs are in regions of the genome that harbor genes related to thermotolerance, reproduction and negative energy balance. The results found in both studies reinforce regions of the BTA 20 chromosome as potential candidates for the selection of these characteristics.