Simone Guimarães

Universidade Federal de Viçosa (UFV) | UFV · Department of Animal Science

This study investigated the effects of age and FSH treatment on the ovarian response, follicular fluid (FF) biochemical composition, nuclear maturation, and molecular profile of cumulus-oocytes complexes (COCs) recovered from prepubertal gilts. Thirty-five prepubertal gilts were separated according to age [140 (n = 20) or 160 (n = 15) days], and wi...

Arsenic is an environmental toxicant known to be a carcinogen and endocrine disruptor. Maternal exposure to arsenic has been associated with fetus malformation and reproductive disorders in male offspring. However, it is unclear the extent to which those effects remain during postnatal development and adulthood. Therefore, this study aimed to inves...

Our objective was to establish a SNPs panel for pedigree reconstruction using microarrays of different densities and evaluate the genomic relationship coefficient of the inferred pedigree, in addition to analyzing the population structure based on genomic analyses in Gir cattle. For parentage analysis and genomic relationship, 16,205 genotyped Gir...

This study investigated the effect of age and follicle stimulating hormone (FSH) treatment on the estradiol (E2) plasma concentration, ovarian follicle development, endometrial histomorphometry, and ultrasonographic parameters of the ovaries and uterus in prepubertal gilts. Thirty-five prepubertal gilts were grouped according to age (140 or 160 d),...

This study is aimed at estimating genetic parameters, effective population size, inbreeding, and inbreeding depression for birth weight, weaning weight, and average pre-weaning daily weight gain (ADG) in Piau pigs. We used information from 3841 Piau pigs, and four linear models were fitted in single-trait analyses, including or excluding maternal g...

Runs of homozygosity (ROH) and signatures of selection are results of selection processes in livestock species that has been shown to affect several traits in cattle. The aim of the current work was to verify the profile of ROH and inbreeding depression in the number of total (TO) and viable oocytes (VO), and number of embryos (EMBR) in Gir Indicin...

This study evaluated the effects of dietary macauba pulp on the growth performance, carcass, and pork traits of growing-finishing pigs; and whether differences in residual feed intake breeding values could influence the pigs’ growth responses to macauba pulp inclusion in the diet. A total of 282 (34.8 ± 4.40 kg) pigs (barrows and females), progeny...

Horses are seasonal polyoestrous animals, and the photoperiod is the main factor modulating their reproductive activity. There is no consensus on the andrological and biochemical factors that influence breeding seasonality. To assess the involvement of climate in reproduction, Mangalarga Marchador stallions were monitored over 1 year regarding seme...

Context. Boar taint compounds (androstenone, skatole and indole) can be measured in pig carcasses, after slaughter or, alternatively, in biopsies of subcutaneous adipose tissue from selected living pigs. Measuring these compounds via biopsy enables data collection in selected animals and high standardisation regarding tissue-collection procedures f...

Meat traceability and certification increase consumers’ confidence in making purchasing decisions. In Brazil, certified Angus beef follows specific regulation, which requires a minimum of 50% of Angus genome in its breed composition to be commercialized as certified Angus beef. Because the majority of the beef produced in Brazil is Nellore-based, t...

Our objective was to establish a SNPs panel for pedigree reconstruction using chips of different densities and evaluate the genomic relationship coefficient of the inferred pedigree, in addition to analyzing the population structure based on genomic analyses in Gir cattle. For parentage analysis and genomic relationship, 16,205 genotyped Gir animal...

Context Greater production of oocytes and embryos from Gir donors contributes to greater fertility and genetic progress. Aims This study aimed to obtain genetic parameters for oocyte and embryo production in the Gir breed. Methods Repeatability and random regression models were applied to data consisting of 17 526 Ovum Pick Up observations from 164...

Background Five hundred 8-d old male broilers Cobb500 were randomly allotted into 10 treatments in factorial arrangement with 5 Cu levels (0, 4, 8, 12, and 16 mg/kg), and 2 sources (Cu proteinate, CuPro and Cu sulphate, CuSO4.5H2O) for a 10-d-experiment. Results Feed conversion ratio (FCR) was better (P < 0.05) in CuPro fed chicks compared with Cu...

This study aimed to estimate genetic parameters, effective population size, inbreeding, and inbreeding depression for birth weight, weaning weight, and average pre-weaning daily weight gain (ADG) in Piau breed pigs. We used information from 3841 Piau pigs, and four linear models were fitted in single trait analyzes including or excluding maternal g...

Backfat is an important trait in pork production, and it has been included in the breeding objectives of genetic companies for decades. Although adipose tissue is a good energy storage, excessive fat results in reduced efficiency and economical losses. A large QTL for backfat thickness on chromosome 5 is still segregating in different commercial pi...

This study aimed to evaluate the endometrial angiogenesis of pregnant commercial line and Piau gilts during early pregnancy. We used 27 gilts, divided into three groups according to the type of mating: Commercial (n = 9), commercial line females mated with commercial line males; Cross-mated (n = 9), Piau females mated with commercial line males; an...

The weighted single-step genome-wide association study (WssGWAS) and post-GWAS analysis may be a useful tool to identify quantitative trait loci (QTL) and candidate genes linked to economically important phenotypes, such as boar taint in pigs. The boar taint is an unpleasant taste and smell observable at uncastrated pork cooking. Therefore, we aime...

Objetivou-se eleger um painel reprodutível e preciso para teste de paternidade em bovinos Gir Leiteiro, usando marcadores SNP comuns a diferentes chips comerciais. Foram utilizados dados genotípicos de 16.205 animais, provenientes de quatro diferentes chips comerciais para bovinos, sendo utilizados para análise apenas os 1.810 marcadores comuns a e...

Resumo: O objetivo deste estudo foi avaliar as herdabilidades e as correlações genéticas e fenotípicas para número de oócitos (total e viáveis) e de embriões em gado Gir Leiteiro. O banco de dados continha informações de 17.526 aspirações foliculares de 1.641 doadoras Gir de diferentes rebanhos. Foi realizada análise multi-característica para númer...

Macauba (Acrocomia aculeata) is an oleaginous palm native to tropical America that has received increased attention from the biofuel, food, cosmetic and pharmaceutical industries due to its high productivity and oil quality. Concomitantly, studies have suggested the potential use of macauba coproducts in ruminant feeding with still scarce informati...

Since pre- and postnatal development are programmed during early prenatal life, studies addressing the complete transcriptional landscape during organogenesis are needed. Therefore, we aimed to disentangle differentially expressed (DE) genes between fetuses (at 35 days old) and embryos (at 25 days old) through RNA-sequencing analysis using the pig...

Objetivamos estimar parâmetros genéticos para os parâmetros da curva de crescimento não-linear de Gompertz com base no método em duas etapas e em dados simulados de uma população de suínos. Dados de valores genéticos reais, dos parâmetros da curva de crescimento (a, b e k) e dos pesos corporais aos 1, 90, 210, 360 e 540 dias de idade foram simulado...

Gastrointestinal nematodes (GIN) parasitism is a very important problem on livestock production, especially in cattle, where the infections are usually subclinical making difficult the diagnosis and aggravating the losses caused by these parasites. This study aimed to identify genomic regions associated with nematode fecal egg count (FEC) in a Gir...

Arsenic is a pollutant widely found in the environment due to natural and anthropogenic sources. Exposure to arsenic forms in drinking water has been related with male reproductive dysfunctions in humans and experimental animals at adult age. However, the impact of this pollutant on postnatal reproductive development of male offspring exposed in ut...

Biological information regarding markers and gene association may be used to attribute different weights for single nucleotide polymorphism (SNP) in genome‐wide selection. Therefore, we aimed to evaluate the predictive ability and the bias of genomic prediction using models that allow SNP weighting in the genomic relationship matrix (G) building, w...

Abstract Background Bacterial chondronecrosis with osteomyelitis (BCO) develops in the growth plate (GP) of the proximal femur and tibia and is initiated by damage to the less mineralized chondrocytes followed by colonization of opportunistic bacteria. This condition affects approximately 1% of all birds housed, being considered one of the major ca...

Arsenic induces reproductive disorders in pubertal males after prepubertal exposure. However, it is unclear the extent to which those effects remain in testis and epididymis of sexually mature rats after arsenic insult. This study evaluated the effects of prepubertal arsenic exposure in male organs of pubertal rats, and their reversibility in adult...

Arsenic is a pollutant widely found in the environment due to natural and anthropogenic sources. Exposure to arsenic forms in drinking water has been related with male reproductive dysfunctions in humans and experimental animals at adult age. However, the impact of this pollutant on postnatal reproductive development of male offspring exposed in ut...

Arsenic induces reproductive disorders in pubertal males after prepubertal exposure. However, it is unclear the extent to which those effects remain in testis and epididymis of sexually mature rats after arsenic insult. This study evaluated the effects of prepubertal arsenic exposure in male organs of pubertal rats, and their reversibility in adult...

Evaluations of replacement heifers in intensively managed grazing systems in tropical conditions are warranted. Thus, we aimed to evaluate performance, muscle and mammary gland development, oocyte quality, and in vitro production of embryos of crossbred heifers grazing an intensively managed pasture and supplemented with high or low protein concent...

Reproductive performance is one of the most important factors for the productive efficiency in beef cattle production. Biometric testicular and physical and morphological traits of the ejaculate are used to evaluate the reproductive performance of bulls. The phenotypic data of semen physical and morphological traits are expressed in percentage or n...

Milk production is economically important to the Brazilian agribusiness, and the majority of the country's milk production derives from Girolando (Gir × Holstein) cows. This study aimed to identify quantitative trait loci (QTL) and candidate genes associated with 305-d milk yield (305MY) in Girolando cattle. In addition, we investigated the SNP-spe...

Dietary l‐arginine (ARG) supplementation has been studied as a nutritional strategy to improve reproductive performance of pregnant sows, since arginine is a conditionally essential amino acid. However, reports addressing the molecular mechanisms that mediate supplementation effects on embryos and fetuses development are still scarce. Therefore, we...

We aimed to evaluate apoptosis and myogenesis related genes expression in embryos and fetuses from two divergent genetic groups of pigs: Piau breed and a commercial line. Thirty females (15 Piau and 15 commercial line) were selected at 120 days of age. Estrous cycle was observed and on the third estrus females were considered sexually mature. Gilts...

We examined the effect of lipid content in the diet on the transcriptome of the Longissimus dorsi muscle in pigs. Our objective was to examine changes at the molecular level affecting economically relevant meat quality characteristics such as intramuscular fat deposition and fatty acid profile. The treatments consisted of isoproteic and isoenergeti...

Sexual dimorphism is a relevant factor in animal science, since it can affect the gene expression of economically important traits. Eventually, the interest in the prenatal phase in a transcriptome study may not comprise the period of development in which male and female conceptuses are phenotypically divergent. Therefore, it would be interesting i...

Nellore is the main cattle breed used in Brazil, being the largest commercial herd in the world. Beyond the importance of male reproductive efficiency for farm profit, the use of reproductive techniques, mainly artificial insemination, turns the evaluation of male reproductive traits even more important. Estimation of genetic parameters increases t...

l-arginine supplementation of sows has led to improvement of reproductive performance, but the mechanisms responsible for the positive effects of arginine during gestation on conceptuses survival and development are still poorly understood. Thus, we aimed to evaluate effects of 1.0% l-arginine supplementation (ARG) on phenotypic traits of commercia...

During gestation, nutrition is the main environmental factor that influences the intrauterine environment and, consequently, development of embryos and fetuses. In this context, l-arginine supplementation of pregnant sows has been shown to be efficient to improve females’ reproductive performance and conceptuses development. Among the products of a...

In pig breeding, selection commonly takes place in purebred (PB) pigs raised mainly in temperate climates (TEMP) under optimal environmental conditions in nucleus farms. However, pork production typically makes use of crossbred (CB) animals raised in non-standardised commercial farms, which are located in TEMP but also in tropical and subtropical r...

Heat stress is an important issue in the global dairy industry. In tropical areas, an alternative to overcome heat stress is the use of crossbred animals or synthetic breeds, such as the Girolando. In this study, we performed a genome-wide association study (GWAS) and post-GWAS analyses for heat stress in an experimental Gir × Holstein F2 populatio...

We aimed to evaluate the effects of paternal genotypes (Piau, Duroc-based, and Pietrain) and nutritional plans with different digestible lysine contents (Low, Medium, and High) on performance, carcass, and meat quality traits of pigs. Pietrain and Duroc crossbred barrows and gilts were similar in performance and carcass traits and had the greatest...

Background: Feed efficiency is one of the most important parameters that affect beef production costs. The energy metabolism of skeletal muscle greatly contributes to variations in feed efficiency. However, information regarding differences in proteins involved in the energy metabolism of the skeletal muscle in beef cattle divergently identified f...

We aimed to characterize the expression of angiogenesis-related genes in corpus luteum (CL) and cumulus cells (CC) during estrous cycle in gilts of different genetic groups, as well as to study the relation between gene expression and phenotypic data. Forty five gilts were used as follows: L1, Commercial Line 1 (Large White x Landrace x Duroc) (n =...

This study aimed to describe longitudinal testicular volume (TV)data of Nellore bulls by using nonlinear mixed models. Dataset consisted of 2,294 TV measurements from 505 bulls with ages ranging from 563 to 4,307 days. Nine nonlinear models were evaluated: Brody, Gompertz, Hill, Logistic I and II, Meloun, Michaelis-Menten, Mitscherlich and von Bert...

Aiming to reduce feed costs, cottonseed oil (CSO) has been used as an alternative component in diets for broilers. However, this oil contains gossypol, an antinutritional agent that impacts the use of mineral elements, inhibits glucose uptake, and has a direct inhibitory action on intestinal enzymes. Nevertheless, toxic effects of gossypol can be p...

Background Bulls are of great importance in the productive chain and for this reason they should have a good semen quality. There is no doubt that sperm morphology is very important to bull fertility, although little is known about how exactly the abnormal morphologies may affect sperm functions. Objectives To detail the morphological description...

This study aimed to assess characteristics of bovine cryopreserved sperm and evaluate its relation to field fertility in fixed‐time artificial insemination (FTAI). Semen samples of 16 bulls were used to inseminate 811 Nellore cows and four of these bulls were also used to inseminate 101 Nellore heifers. Samples of the same ejaculate used for FTAI f...

Background This study investigated if the allele effect of a given single nucleotide polymorphism (SNP) for crossbred performance in pigs estimated in a genomic prediction model differs depending on its breed-of-origin, and how these are related to estimated effects for purebred performance. Results SNP-allele substitution effects were estimated f...

Rhipicephalus (Boophilus) microplus is the main cattle ectoparasite in tropical areas. Gir × Holstein crossbred cows are well adapted to different production systems in Brazil. In this context, we performed genome-wide association study (GWAS) and post-GWAS analyses for R. microplus resistance in an experimental Gir × Holstein F2 population. Single...

The objective of this work was to evaluate the use of regularized quantile regression (RQR) to predict the genetic merit of pigs for asymmetric carcass traits, compared with the Bayesian lasso (Blasso) method. The genetic data of the traits carcass yield, bacon thickness, and backfat thickness from a F2 population composed of 345 individuals, gener...

The present study aimed to evaluate the mechanisms modulated by dietary arginine supplementation to sows during lactation regarding antioxidant capacity and vascularization of mammary glands. At 109 days of gestation, animals were transferred to individual farrowing crates equipped with manual feeders and automatic drinker bowls. Environmental temp...

O reprodutor tem grande importância na cadeia produtiva por possuir maior potencial de difusão do seu material genético dentro do rebanho do que as fêmeas que produzem apenas uma cria por ano, em manejo de monta natural. Entretanto, este potencial somente se torna real quando os machos apresentam boa qualidade seminal, resultando em menores taxas d...

Background: In recent years, there has been increased interest in the study of the molecular processes that affect semen traits. In this study, our aim was to identify quantitative trait loci (QTL) regions associated with four semen traits (motility, progressive motility, number of sperm cells per ejaculate and total morphological defects) in two...

This study aimed to evaluate the correlation between testicular biometry and semen variables, as well as, to relate testicular variables to the probability of selecting Nellore bulls with desirable sperm morphology when conducting breeding soundness evaluations (BSE). A total of 2055 BSEs from 506 bulls comprised the dataset. Biometric variables ev...

A major objective of pork producers is to reduce production cost. Feeding may account for over 75% of pork production costs. Thus, selecting pigs for feed efficiency (FE) traits is a priority in pig breeding programs. While in the Americas, pigs are typically fed high-input diets, based on corn and soybean meal (CS); in Western Europe, pigs are com...

Global pig breeding programmes that have a central breeding goal, do not necessarily select the best pigs for specific local circumstances if genotype by environment interaction (GxE) is present. There is evidence for GxE for feed efficiency (FE) traits. While in the Americas, pigs are typically fed high-input diets based on corn and soybean meal (...

The LocalPork project aims to improve the efficiency of pork production in Brazil. Pigs in Brazil are usually fed a diet based on corn and soybean. Growing these pigs on a diet that includes local alternative ingredients raises a number of questions related to breeding for such an environment. First, what is the economic and environmental impact of...

O objetivo deste trabalho foi avaliar duas importantes metodologias estatísticas destinadas a avaliar perfis de expressão gênica em condições biológicas distintas (DESeq e baySeq) com a finalidade de verificar a influência do número de repetições na identificação de genes diferencialmente expressos (GDE); assim como avaliou a sobreposição dos GDE e...

Crude glycerin has been used as an alternative energy source in animal feeding and can thus change both the animal's performance and the levels of gene expression related to energy production process and the antioxidant system, since the effect of glycerin depends on its degree of purity in the diet. The aim of this study was to evaluate the effect...

Nonlinear mixed models were used to describe longitudinal scrotal circumference (SC) measurements of Nellore bulls. Models comparisons were based on Akaike’s information criterion, Bayesian information criterion, error sum of squares, adjusted R² and percentage of convergence. Sequentially, the best model was used to compare the SC growth curve in...

Monthly temperatures (minimum and maximum) of the farm MS (Last 30 years). Available from: https://www.climatempo.com.br/climatologia/4987/doisirmaosdoburiti-ms. (DOCX)

Scrotal circumference growth curves of Nellore bulls estimated by Hill, Meloun, Michaelis-Menten and Tanaka models. (DOCX)

Monthly temperatures (minimum and maximum) of the farm SP (Last 30 years). Available from: https://www.climatempo.com.br/climatologia/2381/magda-sp. (DOCX)