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RESUMO As raças taurinas de origem ibérica Limonero e Carora (Bos primigenius taurus) possuem o fenótipo de pelo curto, liso e com baixa densidade folicular, o que confere a esses animais maior tolerância térmica e melhor produtividade em regiões quentes. Diferentes mutações associadas a esse fenótipo foram descritas no gene do receptor de prolactina PRLR, localizado no cromossomo bovino BTA20. Uma mutação recentemente encontrada é a substituição do nucleotídeo C por T, SNP 39136666 (p. R497*), no exon 11, que gera um códon de parada e, consequentemente, uma menor isoforma desse receptor. Neste trabalho, desenvolveu-se um protocolo rápido e de baixo custo para detecção desse SNP, utilizando-se a técnica de tetra-primer ARMS-PCR. Assim, foi possível detectar essa mutação nas raças brasileiras de origem ibérica localmente adaptadas: Caracu, Crioulo Lageano, Mocho Nacional e Pantaneiro. O alelo T foi mais frequente na raça Caracu (80%), enquanto o alelo C foi mais frequente na raça Crioulo Lageano (84%). Essa simples metodologia pode ser usada para genotipar esse SNP e ajudar na aplicação dessas informações moleculares em programas de melhoramento focados na tolerância térmica em bovinos taurinos e seus mestiços.

Cattle population history, breeding systems, and geographic subdivision may be reflected in runs of homozygosity (ROH), effective population size (Ne), and linkage disequilibrium (LD) patterns. Thus, the assessment of this information has become essential to the implementation of genomic selection on purebred and crossbred cattle breeding programs. In this way, we assessed the genotype of 19 cattle breeds raised in Brazil belonging to taurine, indicine, synthetic crossbreds, and Iberian-derived locally adapted ancestries to evaluate the overall LD decay patterns, Ne, ROH, and breed composition. We were able to obtain a general overview of the genomic architecture of cattle breeds currently raised in Brazil and other tropical countries. We found that, among the evaluated breeds, different marker densities should be used to improve the genomic prediction accuracy and power of genome-wide association studies. Breeds showing low Ne values indicate a recent inbreeding, also reflected by the occurrence of longer ROH, which demand special attention in the matting schemes to avoid extensive inbreeding. Candidate genes (e.g., ABCA7, PENK, SPP1, IFNAR1, IFNAR2, SPEF2, PRLR, LRRTM1, and LRRTM4) located in the identified ROH islands were evaluated, highlighting biological processes involved with milk production, behavior, rusticity, and fertility. Furthermore, we were successful in obtaining the breed composition regarding the taurine and indicine composition using single-nucleotide polymorphism (SNP) data. Our results were able to observe in detail the genomic backgrounds that are present in each breed and allowed to better understand the various contributions of ancestor breeds to the modern breed composition to the Brazilian cattle.

The Brazilian Guzerá population originated from a few founders introduced from India. These animals adapted well to the harsh environments in Brazil, were selected for beef, milk, or dual-purpose (beef and milk), and were extensively used to produce crossbred animals. Here, the impact of these historical events with regard to the population structure and genetic diversity in a Guzerá meta-population was evaluated. DNA samples of 744 animals (one dairy, nine dual-purpose, and five beef herds) were genotyped for 21 microsatellite loci. Ho, He, PIC, Fis, Fit, and Fst estimates were obtained considering either farms or lineages as subpopulations. Mean Ho (0.73) and PIC (0.75) suggest that genetic diversity was efficiently conserved. Fit, Fis and Fst values (95% CI) pointed to a low fixation index, and large genetic diversity: Fit (Farms = 0.021–0.100, lineages = 0.021–0.100), Fis (Farms = –0.007–0.076, lineages = −0.014–0.070), and Fst (Farms = 0.0237–0.032, lineages = 0.029–0.038). The dual-purpose herds/selection lines are the most uniform subpopulation, while the beef one preserved larger amounts of genetic diversity among herds. In addition, the dairy herd showed to be genetically distant from other herds. Taken together, these results suggest that this Guzerá meta-population has high genetic diversity, a low degree of population subdivision, and a low inbreeding level.

Recent molecular tools and technologies have marked the discovery of the origin and domestication processes of a wide variety of species, using either genomic or mitochondrial molecular markers to provide input for selection programs, as well as the management and conservation of animal breeds. This study aimed to analyze genes of mitochondrial DNA of the following sheep (Ovis aries) breeds: Pantaneira, Bergamácia, Dorper, White Dorper, Ile de France and Hampshire Down, to obtain their population genetic parameters and investigate the origin of these sheep populations reared in the State of Mato Grosso do Sul. The analysis of mitochondrial DNA allowed to infer their phylogenetic relationships and revealed significant differences among them when compared with each other and with sequences obtained from GenBank. Through the formation of haplotypes, it was noted that the Pantaneira breed served as the maternal basis for the formation of the other breeds reared in the region, and it was possible to suggest a European origin for the sheep populations studied.

Genetic diversity is one of the most important issues in studies on conservation of cattle breeds and endangered species. The objective of this study was to estimate the levels of genetic differentiation between locally adapted taurine (Bos taurus taurus) and zebu (Bos taurus indicus) breeds in Brazil, which were genotyped for more than 777,000 SNPs. The fixation index (F ST), principal component analysis (PCA), and Bayesian clustering were estimated. The F ST highlighted genetic differentiation between taurine and zebu breeds. The taurine lines, Caracu and Caracu Caldeano, had significant genetic differentiation (F ST close to 5%) despite their recent selection for different uses (meat and milk). This genetic variability can be used for conservation of locally adapted animals, as well as for breeding programs on zebu breeds. Introgression of zebu in locally adapted breeds was identified, especially in Curraleiro Pe-Duro breed. The Gyr breed, however, had low breed purity at genomic level due to its very heterogeneous mixing pattern.

This study aimed to identify bovine breeds through trichological morphology and morphometry and to validate this technique by comparing it with genetic characterization. Animals from Caracu, Curraleiro P&eacute, Duro, Nelore, and Bovino Pantaneiro breeds were studied. Morphological and morphometric analyses of the guard hairs were performed. The cuticular pattern was observed on the shaft and the medulla pattern on the shield of the samples. The cattle genetic characterization was accomplished using microsatellite markers. Statistical analyses were performed using R version 3.2.4 software. Pearson&rsquo, s correlation test showed a high positive and significant correlation between the matrices generated by trichological and genetic analyses (r = 0,996 and p &lt, 0.001). Trichological analysis is a useful method for cattle breed identification. Its potential for identifying other species of interest for animal production should be studied since it is a simple, low-cost, and non-invasive method.

Pesquisas em regiões do DNA mitocondrial de Ovis aries mostraram a existência de haplogrupos de origem asiática e européia. Assim o objetivo do presente estudo foi aplicar o teste molecular de PCR-RFLP do gene mitocondrial citocromo oxidase I com a enzima de restrição HinfI para caracterizar, em relação aos haplogrupos existentes, algumas raças de ovinos criadas no Estado do Mato Grosso do Sul. Foram analisadas amostras de DNA de 155 animais pertencentes a sete raças de ovinos. Dezesseis animais foram identificados como pertencendo ao haplogrupo asiático, representados pelas raças Ile de France (n=3), Dorper (n=2), White Dorper (n=9) e Suffolk (n=2). Os outros 139 animais foram identificados como haplogrupo europeu, representantes das raças Pantaneira (n=40), Brazilian Bergamácia (n=21), Ile de France (n=17), Dorper (n=17), White Dorper (n=6), Hampshire Down (n=20) e Suffolk (n=18). Os resultados indicaram que a maioria dos animais pertenciam ao haplogrupo europeu, evidenciando a origem europeia das raças criadas no Estado. A identificação da origem desses animais possibilita melhorar o manejo das populações localmente adaptadas visando sua conservação e o seu aproveitamento no Estado.

The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups were identified with 33 polymorphic sites. Haplotype diversity (varying from 0.20 to 0.96) and nucleotide diversity (varying from 0.0039 to 0.0239) was lower for locally adapted than for specialized breeds, with the same pattern observed for FST values. Haplogroups identified in Brazilian breeds are in agreement with previous findings in South American samples. The low variability observed mainly in locally adapted breeds, indicates that, to ensure conservation of these breeds, careful reproductive management is needed. Additional genetic characterization studies are required to support accurate decision-making.

article i nfo Background: The aim of the present study was to assess the genetic diversity of Pantaneiro sheep, using microsatellite markers, in order to assist maintenance and management plans, enhance mating systems and reduce the inbreeding rate. A total of 127 animals were genotyped at eight microsatellite loci. They belonged to populations from the Experimental Farm of the Universidade Federal da Grande Dourados (UFGD) (Dourados/MS/Brazil) and Embrapa Pantanal (Corumba/MS/Brazil). Results: The population of Pantaneiro sheep from the UFGD exhibited a high mean number of alleles (11.13) and allelic richness (10.66). The polymorphic information content was highly informative in the locus studied, resulting in a mean value of 0.71. Observed heterozygosity was lower than expected for all molecular markers assessed. The analysis of molecular variance showed a differentiation rate of 5.2% between populations. Conclusions: The results of the statistical parameters indicated that populations of Pantaneiro sheep require special attention on herd management, and it's further necessary to implement breeder exchange programs in order to preserve the genetic variability of these populations. Furthermore, the maintenance of those populations in their typical habitats is rather required to allow different responses from the herds to the interactions between genotype and environment.

Morphometry and ultrasound of carcasses were used to estimate the growth curve of Criola Lageana cows, raised under natural conditions. A total of 111 cows, raised under extensively production system in Central Plateau of Santa Catarina, were evaluated. Morphometrics and ultrasound measurements were related with the age of the animals using the targeted univariate regression model, assigning the variable response to gamma distribution. The inflection points of the growth curve were 24 and 25 months for withers height and hip height, between 27 and 29 for weight, body length, rump length, thorax perimeter, depth and distance between ilea. For ribeye area (REA), inflection point was 18 months. The Crioula Lageana cows presented greater growth velocity around 27 months, showing good productive performance under the natural conditions of the Central Plateau of Santa Catarina.

The objective of this study was to identify, through the DNA barcode, fishable Siluriformes which were collected from the Paraguay River basin in Pantanal. It was analyzed for genetic distance calculation using the Kimura-two-model parameters and the dendrogram was builtusing the Neighbour-Joining algorithm. The average genetic distance within species, genus and families were 0.2%, 1.6% and 4.2%, respectively. These values were lower than those reported in studies from other continents, probably due to the recent radiation process undergone by Neotropical fish. The dendrogram revealed two possible cases of hybridization, one individual Pseudoplatystoma corruscans, it was not possible to identify whether it was a natural event or commercial production exhaust and other of Pimelodus cf. argenteus leading to the assumption that the aspects of reproductive isolation cannot be clearly defined. Besides, the populations of the species Hemisorubim platyrhynchos and e Platydora armatulus may be undergoing a substructuring process, with genetic differences 3% and 4%, respectively.

RESUMO Objetivou-se com este trabalho realizar o inventário do ecótipo Gurgueia no Estado do Piauí, na região Nordeste do Brasil. O inventário compreendeu o levantamento histórico, com busca em literaturas, e o populacional feito a partir de visitas in loco nos rebanhos. Foi tomado em cada rebanho a localização geográfica por meio o por GPS e contagem dos animais com padrão fenotípico Gurgueia para classifica-la quanto ao risco de extinção. Observou-se a presença dos caracteres barba, chifres, brincos, os padrões de cor ruão, agouti e chocolate, e a presença de orelha reduzida que foram submetidos à análise descritivas simples. A literatura regional consultada não apresentou consistência sobre a origem do caprino Gurgueia no Piauí, mas indicaram que rebanhos instalados no vale do rio Gurgueia no Sul do Piauí, deram origem aos hoje classificados como Gurgueia. No estudo, houve a confirmação de poucos exemplares, apenas 119, dispersos em três microrregiões revelando que grupo genético Gurgueia está em situação crítica de desaparecimento. Nestes animais, observa-se alta frequência da ausência de brincos e do caráter presença de chifre (0,95). A frequência de barba foi de 0,52 e não houve ocorrência de pelos longos, indicando ausência da relação entre esses caracteres. O caráter ruão (0,96), a pelagem chocolate e padrão não-agouti (cor única) não estiveram presentes assim como a presença de orelha reduzida. O estudo pode apontar também que os caprinos Gurgueia apresentam-se em situação instável, já que a sua presença nos rebanhos está associada a outros tipos raciais. SUMMARY The purpose of this study was to conduct the inventory of goat breed Gurgueia in the state of Piauí, Northeast region of Brazil. The inventory includes a historical survey - made by searching in the literature - and a population survey - made by gathering in loco information. The geographic location through GPS was taken in farms sheltering Gurgueia goats and then individuals Gurgueia were counted to estimate population size and classifying the risk of extinction. To characterize the Gurgueia breed, the presence of beard, horns, earrings, patterns of color roan, agouti and brown, and the presence of reduced ear were observed to perform simple descriptive analysis. The regional literature demonstrates lack of consistency about the origin of the Gurgueia breed. However, flocks of goats in the Gurgueia river valley, in Southern Piauí, gave origin to the breed denomination. The present study found out 119 Gurgueia individuals scattered in three micro-regions - classifying the Gurgueia breed as critically endangered. The morphological analysis shows low frequency of earrings (0,05) and high frequency of horn (0.95) in Gurgéia individuals. The beard frequency was 0.52 and was verified absence of long hairs, indicating no relationship between those. The analysis showed high frequency of roan pattern (0.96), absence of brown and single coat pattern (non-agouti). Reduced ear was absent. This inventory appointed that Gurgueia risk of endangerment is unstable, since its presence within herds is mixed with other breed types.

The objective of this study was to compare physiological and thermographic responses to heat stress in three breeds of cattle. Fifteen animals of each of the Nelore, Pantaneiro and Curraleiro Pe-Duro breeds, of approximately two years of age, were evaluated. Heart and respiratory rates, rectal and surface temperature of animals as well as soil temperature were recorded at 8:30 and 15:30 on six days. Variance, correlation, principal factors and canonical analyses were carried out. There were significant differences in the rectal temperature, heart and respiratory rate between breeds (p < 0.001). Nelore and Pantaneiro breeds had the highest rectal temperatures and the lowest respiratory rate (p < 0.001). Breed was also significant for surface temperatures (p < 0.05) showing that this factor significantly affected the response of the animal to heat tolerance in different ways. The Curraleiro Pe-Duro breed had the lowest surface temperatures independent of the period evaluated, with fewer animals that suffered with the climatic conditions, so this may be considered the best adapted when heat challenged under the experimental conditions. Thermography data showed a good correlation with the physiological indexes, and body area, neck and rump were the main points.

The objective of this study was to evaluate and compare the transfer of passive immunity and the proteinogram in Criollo Lageano (CL) and Black and White Holstein (BWH) calves. Two groups were utilized with 13 Criollo Lageano and 10 BWH calves. Blood samples were collected for the measurement of total serum protein, electrophoresis of serum proteins, activity of the gamma glutamyl transferase, and concentration of IgG by the method of the zinc sulfate turbidity in periods between 24 and 36 hours of life, 15, 30, 60, 90, 120, 150 and 180 days. Statistical analysis was performed by ANOVA and Tukey test at 5% significance level, and correlations between variables were calculated. Variations of serum proteins followed a pattern of physiological behavior over the first six months of life and production of immunoglobulins was active earlier in BWH calves and slower in the Criollo Lageano, without causing any impact on their health. Gamma globulin in the first days of life (24-36h) was correlated with IgG (r=0.87 for CL and r=0.89 for BWH), PTS (r=0.91 for CL and r=0.92 for BWH), Glob (r=0.99 for CL and r=0.98 for BWH) and GGT (r=0.14 for CL and r=0.83 for BWH). It was concluded that there was no failure in the transfer of passive immunity in Criollo Lageano calves but this failure occurred in the BWH calves. IgG values estimated by the zinc sulfate turbidity and serum proteins were considered good indicators of the transfer of passive immunity in calves between 24 and 36 hours of life. O objetivo do presente trabalho foi verificar e comparar a transferência de imunidade passiva e o proteinograma em bezerros da raça Crioula Lageana (CL) e Holandesa Preta e Branca (HPB). Foram utilizados dois grupos sendo 13 bezerros da raça Crioula Lageana e 10 da raça HPB. Amostras de sangue foram colhidas para a mensuração da proteína sérica total, eletroforese das proteínas séricas, atividade da gama-glutamiltransferase e concentração de IgG pelo método de turvação pelo sulfato de zinco nos períodos entre 24 e 36 horas de vida, 15, 30, 60, 90, 120, 150 e 180 dias. A análise estatística foi realizada pelo teste de ANOVA e Tukey ao nível de 5% de significância, e correlações entre as variáveis. As variações das proteínas séricas obedeceram a um padrão de comportamento fisiológico ao longo dos seis primeiros meses de vida e a produção ativa de imunoglobulinas foi mais precoce nos bezerros da raça Holandesa e mais lenta nos da raça Crioula Lageana, sem provocar qualquer impacto sobre a saúde dos mesmos. A gamaglobulina no primeiro dia de vida (24-36h) correlacionou-se com a IgG (r=0,87 CL e r=0,89 HPB), PTS (r=0,91 CL e r=0,92 HPB), Glob (r=0,99 CL e r=0,98) e GGT (r=0,14 CL e r=0,83 HPB). Conclui-se que não houve falha na transferência de imunidade passiva nos bezerros da raça Crioula Lageana e falha na raça Holandesa Preta e Branca. Os valores de IgG estimados pelo método da turvação pelo sulfato de zinco e das proteínas séricas foram bons indicadores da transferência de imunidade passiva nos bezerros entre 24 e 36 horas de vida.

Genetic variability at 11 microsatellite markers was analyzed in five naturalized/local Brazilian horse breeds or genetic groups. Blood samples were collected from 328 animals of the breeds Campeira (Santa Catarina State), Lavradeira (Roraima State), Pantaneira (Pantanal Mato-Grossense), Mangalarga Marchador (Minas Gerais State), as well as the genetic group Baixadeiro (Maranhão State), and the exotic breeds English Thoroughbred and Arab. We found significant genetic variability within evaluated microsatellite loci, with observed heterozygosis varying between 0.426 and 0.768 and polymorphism information content values of 0.751 to 0.914. All breeds showed high inbreeding coefficients and were not in Hardy-Weinberg equilibrium. The smallest genetic distance was seen between the Pantaneira and Arab breeds. The principal component analyzes and Bayesian approach demonstrated that the exotic breeds have had a significant influence on the genetic formation of the local breeds, with introgression of English Throroughbred in Pantaneira and Lavradeira, as well as genetic proximity between the Arab, Pantaneira and Mangalarga Marchador populations. This study shows the need to conserve traits acquired by naturalized horse breeds over centuries of natural selection in Brazil due to the genetic uniqueness of each group, suggesting a reduced gene flow between them. These results reinforce the need to include these herds in animal genetic resource conservation programs to maximize the genetic variability and conserve useful allele combinations.

Studies were conducted to characterize the effect of season of the year on testicular morphology, fresh and frozen/thawed semen quality from Curraleiro (Pé-duro) bulls in the Brazilian Central west region. Five adult, healthy bulls underwent an andrological examination and semen collection using an electroejaculator, once a month for a year. Fresh and thawed semen were evaluated for progressive sperm motility and sperm vigor, sperm morphology and acrosomal integrity. Testicular length and volume were less (P0.05) in April than in the other months of the year. For fresh semen, the ejaculate in April had less volume and sperm concentration (P0.05), while sperm vigor was less (P0.05) in June, increasing in January and February. With the frozen/thawed semen, the proportion of sperm was greater (P0.05) in April to July, decreasing from October to December. Semen collected in December had the greatest (P0.05) proportion of major defects while that collected in February/March had the highest proportion of minor defects. The proportion of live intact sperm reduced progressively from December to April/May. The marginal influence of the time of the year on testicular biometry and fresh semen in Curraleiro bulls shows the adaptation of this breed to the environmental conditions in the region. Thus, reproduction with natural mating should be successful at any time of year. For frozen semen collection for conservation programs, the best time of year is from June to September.

The genetic diversity within and between five genetic groups of pigs in Brazil, (n = 182) represented by three naturalized breeds (Moura, Piau and Monteiro), one commercial breed (Landrace) and one commercial composite (MS60) was estimated using 28 microsatellite markers. The genetic structure within these groups was also tested. The results showed that 14% of the total variation (p < 0.001) observed was due to differences between breeds. Based on the UPGMA dendrogram obtained from Nei's DA genetic distance it was possible to differentiate three groups. The first was formed by the commercial breed, Landrace, and the composite MS60, the second by two of the naturalized breeds (Piau and Monteiro) and the third by the Moura naturalized breed. Within breed variability indicated that the Piau breed had the highest value of expected heterozygosity among the naturalized breeds, whereas Landrace had the highest value between the commercial breeds. Using a Bayesian analysis, a population substructure was identified in Monteiro and Piau breeds. Furthermore, lower values for breed certification probability were observed for these two breeds as well as a significant genetic differentiation between the Moura and Landrace breeds and the composite MS60. The microsatellite marker panel possessed high precision (99.99%) when used in paternity exclusion in naturalized pig breeds and proved to be an effective tool for the management and conservation of naturalized pig breeds.

Brazil has various species of domestic animals, which developed from breeds brought by the Portuguese settlers soon after the discovery of the country. After being submitted to a long process of natural selection, these breeds present characteristics adapted to specific Brazilian environmental conditions, and are known as “criollo”, “local” or naturalized breeds. From the beginning of the 20th century, some exotic breeds, selected in temperate regions, have begun to be imported, and, although more productive, they do not have adaptive traits, such as resistance to disease and parasites found in the naturalized breeds. Even so, they gradually replaced the native breeds, to such an extent that the latter are in danger of extinction. To avoid further loss of this important genetic material, in 1983 the National Research Center for Genetic Resources and Biotechnology (Cenargen) of the Brazilian Agricultural Research Corporation (Embrapa) decided to include conservation of animal genetic resources among its priorities. The conservation activities have been conducted under the Brazilian Genetic Resources Network — Renargen, and is carried out by various research centres of Embrapa, universities and State research institutions, as well as by private farmers, with a single coordinator at national level, Cenargen. The in situ conservation of cattle, horses, buffaloes, donkeys, goats, sheep and pigs is being carried out by Conservation Nuclei, located in the animal's original habitat. Ex situ conservation is centred at the Brazilian Animal Germplasm Bank (AGB), kept at Cenargen. This is responsible for the storage of semen and embryos of various breeds of domestic animals threatened with extinction. Presently the AGB has almost 60,000 doses of semen and more than 250 embryos, as well as over 7000 DNA samples. An important challenge for this program is to increase awareness within the different segments of society in terms of the importance of the conservation of animal genetic resources. The development and evolution of Renargen and its efforts to facilitate the conservation of genetic resources of livestock in Brazil are described in this paper.

2 Embrapa Recursos Geneticos e Biotecnologia ABSTRACT - Most livestock are not indigenous to Brazil. Several animal species were considered domesticated in the pre-colonial period, since the indigenous people manage them as would be typical of European livestock production. For over 500 years there have been periodic introductions resulting in the wide range of genetic diversity that for centuries supported domestic animal production in the country. Even though these naturalized breeds have acquired adaptive traits after centuries of natural selection, they have been gradually replaced by exotic breeds, to such an extent, that today they are in danger of extinction To avoid further loss of this important genetic material, in 1983 Embrapa Genetic Resources and Biotechnology decided to include conservation of animal genetic resources among its priorities. In this paper we describe the effort to genetically characterize these populations, as a tool to ensure their genetic variability. To effectively save the threatened local breeds of livestock it is important to find a niche market for each one, reinserting them in production systems. They have to be utilized in order to be conserved. And there is no doubt that due to their adaptive traits, the Brazilian local breeds of livestock can play an important role in animal production, to meet society needs.

Amostras de sangue foram coletadas de cavalos Pantaneiros de cinco regiões dos estados de Mato Grosso do Sul e Mato Grosso. As raças Mangalarga Marchador, Árabe e Puro-Sangue Inglês (PSI) usando marcadores moleculares RAPD-PCR (Random Amplified Polymorphic DNA – Polymerase Chain Reaction) foram incluídas no intuito de se calcular as distâncias genéticas e comparar a variabilidade genética entre e dentro de cada uma das raças. Dos 146 primers escrutinados, 13 foram escolhidos para amplificação com cada um dos indivíduos das oito populações, gerando um total de 44 bandas polimórficas. Os resultados encontrados na Análise de Variância Molecular (AMOVA) indicam que grande parte da variabilidade genética detectada se deve a diferenças entre indivíduos dentro de populações (75,47%). Na análise da estimativa dos percentuais de variabilidade genética entre pares de populações, foram observados maiores valores para os pares formados entre as cinco populações de cavalo Pantaneiro e a raça Árabe, enquanto os menores percentuais ocorreram entre Pantaneiro e Mangalarga Marchador. Maior índice de diversidade gênica foi observado na raça Pantaneiro (0,3396). No dendrograma gerado pelo método UPGMA, a partir da matriz de similaridade obtida pelo coeficiente de Jaccard, houve distinção entre as raças naturalizadas (Pantaneiro e Mangalarga Marchador) e as exóticas (Árabe e PSI). Os resultados encontrados sugerem que o Pantaneiro apresenta maior variabilidade genética que os de outras raças e está estreitamente relacionado ao Mangalarga Marchador. Blood samples were collected from Pantaneiro Horses in five regions of Mato Grosso do Sul and Mato Grosso States. Arabian, Mangalarga Marchador and Thoroughbred were also included to estimate genetic distances and the existing variability among and within these breeds by RAPD-PCR (Random Amplified Polymorphic DNA – Polymerase Chain Reaction) molecular markers. From 146 primers, 13 were chosen for amplification and 44 polymorphic bands were generated. The analysis of molecular variance (AMOVA) indicated that the greatest portion of detected variability was due to differences between individuals within populations (75.47%). Analysis of the genetic variability between pairs of populations presented higher estimates for the five Pantaneiro populations with the Arabian breed, while lowest estimates were presented by pairs formed among the Pantaneiro populations with the Mangalarga Marchador. Highest genic diversity was shown by the Pantaneiro (0.3396), which also showed highest genetic distance with the Arabian and lowest with Mangalarga Marchador breed. UPGMA dendrogram showed distinct differences between naturalized (Pantaneiro and Mangalarga Marchador) and exotic (Arabian and Thoroughbred) breeds. In the dendrogram generated by UPGMA method, the similarity matrix generated by the Jaccard coefficient showed distinction between the naturalised breeds, Pantaneiro and Mangalarga Marchador, and the exotic breeds, Árab and English Thoroughbred. Results suggest that the Pantaneiro presents a higher genetic variability than the other studied breeds and has a close relationship with the Mangalarga Marchador.

O objetivo deste trabalho foi caracterizar, por meio de marcadores RAPD, dois grupos genéticos de búfalos, Carabao e tipo Baio, que estão sendo conservados in situ, assim como verificar as relações genéticas entre eles e os outros três grupos genéticos de búfalos existentes no Brasil, Murrah, Jafarabadi e Mediterrâneo, considerados raças comerciais. Foram estudados 48 animais de cada grupo, com exceção dos grupos Murrah e Mediterrâneo, com 47 e 42 animais, respectivamente, compreendendo um total de 233 animais. Os 21 iniciadores polimórficos geraram 98 marcadores. A variabilidade genética entre e dentro dos grupos foi estimada em 26,5 e 73,5%, respectivamente, sugerindo divergência significativa entre os cinco grupos genéticos. Na análise entre pares de grupos, foi verificado que a maior e a menor divergência estavam em torno de 40 e 18%, quando se compararam os grupos Carabao x Mediterrâneo e Murrah x Jafarabadi, respectivamente. Entre os grupos Baio e Murrah, a análise revelou divergência genética de 20,42%, indicando que esses grupos são distintos. Os cinco grupos são geneticamente distintos, o que reforça a necessidade de conservação dos grupos genéticos Carabao e Baio, ameaçados de extinção no Brasil. The objective of this work was to characterize genetically, using RAPD markers, two genetic groups of buffalos, Carabao and Baio, which are being conserved in situ, as well as to verify the genetic relationship among them and the other three genetic groups of buffalos raised in Brazil, considered as commercial breeds: Murrah, Jaffarabadi and Mediterrâneo. Forty eight animals of each group were studied, with the exception of the Murrah and Mediterrâneo, in which 47 and 42 animals, respectively, were sampled, comprising a total of 233 animals. The 21 polymorphic primers produced 98 markers. Genetic variability within and between groups was estimated in 26.5 and 73.5%, respectively, suggesting a significant divergence among groups. On the analysis between pairs of groups, the divergence was about 40 and 18%, respectively, when the Carabao x Mediterranâneo and the Murrah x Jaffarabadi were compared. The estimated genetic divergence between Baio and Murrah groups was 20.42%, indicating that they are distinct groups. The five genetic groups are genetically distinct, indicating the need to conserve the Carabao and Baio, two genetic groups in danger of extinction in Brazil.

The identification of new bovine male-specific DNA sequences is of great interest because the bovine Y chromosome remains poorly characterized in terms of physical and genetic maps. Since taurine and zebu Y chromosomes are structurally different, the identification of Y-specific sequences present in both sub-species is particularly important: these sequences are of evolutionary significance and can be broadly used for embryo sexing. In this work, we initially used the random amplified polymorphic DNA (RAPD) technique to search for male-specific sequences present as monomorphic markers in genomic DNA from zebu and taurine bulls. A male-specific RAPD band was found to be present and highly conserved in both sub-species, as demonstrated by Southern blotting, fluorescent in situ hybridization (FISH) and DNA sequencing. In a previous work, a pair of primers derived from this marker was successfully used in taurine and zebu embryo sexing.

Conservation and improvement strategies should be based on the association between genetic and phenotypic characteristics. The objective of this work was to characterize five native Brazilian cattle breeds (Caracu, Crioulo Lageano, Curraleiro, National Polled and Pantaneiro) and two commercial breeds (Holstein and Nellore) using RAPD technique to estimate genetic distances and variability between and within breeds. Genetic relationships were investigated using 22 primers which generated 122 polymorphic bands. Analysis of molecular variance indicated that most of the genetic variation lay among individuals within populations. The genetic variabilities between pairs of breeds were statistically significant. The smallest genetic divergence was between Crioulo Lageano and Curraleiro.The National Polled, although historically considered to be of Bos taurus aquitanicus origin,similar to theCaracu, was grouped together with the other breeds of Bos taurus ibericus origin. Generally, the individual breeds formed distinct clusters except the National Polled. The RAPD technique was capable to distinguish genetically between the breeds studied; the Caracu, Crioulo Lageano, Curraleiro and Pantaneiro may be considered distinct genetic entities thereby proving the uniqueness of the populations; the National Polled has not been able to re-establish itself after its decline in the 1950s, thereby losing its genetic identity. Estratégias para conservação e melhoramento animal devem ser baseadas na associação de características fenotípicas e genéticas. O objetivo deste trabalho foi caracterizar cinco raças nativas brasileiras (Caracu, Crioulo Lageano, Curraleiro, Mocho Nacional e Pantaneiro) e duas comerciais (Holandês e Nelore) pela técnica de RAPD para estimar a distância genética e a variabilidade genética entre e dentro das raças. As relações genéticas foram investigadas utilizando-se 22 primers, que geraram 122 bandas polimórficas. A análise de variância molecular revelou que a maior parte da variabilidade genética total ocorreu em virtude das diferenças de indivíduos dentro das populações. Na comparação da variabilidade genética entre os pares de raças, observou-se que todos os valores obtidos foram estatisticamente significativos. A menor divergência genética foi observada entre Crioulo Lageano e Curraleiro. A raça Mocho Nacional, apesar de historicamente ser considerada de origem Bos taurus aquitanicus,mesma origem da raça Caracu, agrupou-se com as demais raças nativas consideradas de origem Bos taurus ibericus. Demodo geral, as raças estudadas se agruparam em clustersdistintos, com exceção da Mocho Nacional. A técnica de RAPD foi capaz de distinguir geneticamente as raças estudadas; Caracu, Crioulo Lageano, Curraleiro e Pantaneiro podem ser consideradas entidades genéticas distintas, comprovando assim, a unicidade de suas populações; a Mocho Nacional não conseguiu se restabelecer, após seu declínio na década de 50, perdendo, sua identidade genética.

A identificação de parâmetros/ métricas associados à adaptação ambiental é uma das principais tendências e desafios da pecuária mundial. Desta forma, o objetivo deste trabalho foi avaliar as características de tolerância ao calor de bovinos da raça Nelore e Pantaneiro no ecossistema do Pantanal matogrossense no pico de calor da região. Estes animais foram mantidos por duas horas à sombra (8:00h às 10:00h) e em seguida uma hora ao sol (10:00h às 11:00h). Após a exposição foram analisados parâmetros de frequência cardíaca (FC), frequência respiratória (FR), temperatura retal (TR), temperatura superficial da costela (TSC), temperatura superficial do pescoço (TSP) e temperatura superficial da garupa (TSG). Também foram avaliados a taxa de sudação (TXS), comprimento e densidade de pelos e calculados o índice de tolerância ao calor (ITC). No período estudado, a temperatura ambiental variou de 29,0 a 40,0ºC e a média para umidade relativa foi de 75%. O ambiente teve influência marcante sobre as variáveis fisiológicas, com exceção da FR. A TR e a TXS diferiram significativamente entre os grupos genéticos, sendo da raça Nelore mais elevada em relação à Pantaneira, mas todas dentro dos limites fisiológicos. A análise multivariada mostrou a importância de variáveis como taxa de sudação e comprimento de pelos para adaptação de bovinos na região. Apesar do Nelore vermelho estar separado dos outros dois grupos, foi possível concluir que ambas as raças analisadas apresentaram capacidade de adaptação e tolerância ao calor às condições climáticas do Pantanal e podem ser produzidas de modo sustentável na região. Identification of parameters/metrics associated with environmental adaptation is one of the main trends and challenges for livestock worldwide. Thus, this study was conducted at Nhumirim Farm, in Nhecolândia, Pantanal, during the month of February, period with highest ambient temperatures. We used five cattle of each genetic group (White Nelore, Red Nelore and Pantaneira) to evaluate characteristics related to heat tolerance. Heart rate (HR), respiratory rate (RR), rectal temperature (RT), skin temperature (ST), sweating rate (SR), morphometric measurements, hair length (HL) and heat tolerance index (HTI) were evaluated. During the study the air temperature ranged from 29.0 to 40.0ºC and the average relative humidity was 75%. RT and ST were highest in White Nelore, followed by Red Nelore and Pantaneira. The average HTI value for the three groups was between 9 and 10, indicating high tolerance. The environment had considerable effect on physiological variables, except RR, RT and SR that significantly differed between genetic groups, with Nelore being higher than the Pantaneira, but all within physiological limits. Multivariate analysis showed the importance of variables such as sweating rate and hair length for the adaptation of cattle in the region. The red Nelore separated from the other two groups. We conclude, therefore, that both zebu (white and red Nelore) and European (Pantaneira) showed adaptability and heat tolerance to climatic conditions of the Pantanal.

Sheep of the Pantaneiro breed and seven other breeds, raised in the State of Mato Grosso do Sul, Brazil, were genotyped using eight microsatellite loci. The aim of the present study was to determine the genetic variability, phylogenetic relationship, and patterns of gene introgression and miscegenation among the animals surveyed, to obtain information about the genetic structure of locally adapted sheep in Mato Grosso do Sul. A total of 195 animals were used for genetic analysis. The Pantaneiro breed had the largest average number of alleles/locus (9.25), and higher allelic richness (6.95), while the Dorper population had the lowest values for these parameters (4.88 and 3.86, respectively). Analysis of genetic distance values and genetic structure between populations made it possible to characterize these animals with regard to distinct genetic groups. Average expected heterozygosity ranged from 0.72 (Pantaneiro) to 0.55 (Dorper), while average observed heterozygosity ranged from 0.63 (White Dorper) to 0.54 (Dorper). On the basis of the statistical parameters evaluated, it was possible to demonstrate that when compared to other populations, the Pantaneiro breed represented a reservoir of genetic diversity with rare and useful alleles for genetic improvement, emphasizing the importance of preserving the breed.

The objective of this study was to use morphometric and ultrasound evaluations to estimate the growth curve of the Pantaneiro cattle breed, raised in its natural habitat, aiming at the re-insertion of this breed in production systems. One hundred and three females, aging from months to 11 years, and raised on native pastures, were evaluated. The animals belonged to the Conservation Nucleus of Embrapa Pantanal, located in the Pantanal of Mato Grosso do Sul (Brazil). Weight, thoracic perimeter (TP), body length (BL), rump height (RH), height at withers (HW), hip height (HH), depth (DP), distance between the ilia (DI) (cm) and rib-eye area (REA) were measured. To relate the measurements with the age of the animals, the univariate regression model was used, assigning the variable response to gamma distribution. The Pearson correlation between variables was also estimated. The inflection point of the growth curve was 37 months for HH; between 38 and 39 months for TP and HW; between 40 and 41 months for DI, HH and DP; and 45 months for BL. The REA results could not fit in a statistical model. The majority of the variables presented a correlation above 60% among themselves, except for REA × Age, of 15.81%; REA × HW, of 34.44%; HH × Age, of 46.19; HH × DI, of 58.07%; REA × HH, of 24.57%; and REA × TP, of 39.9%. The cows showed maturity age at 40 months, which may have occurred because they were raised in natural farming conditions. In Pantaneiro cows reared in extensive systems only on natural pastures, the use of ultrasound is not effective to estimate the curve of muscular development, perhaps because this breed was not selected for weight gain.

espanolEl objetivo de este trabajo fue realizar un estudio preliminar del cariotipo de bovinos de razas brasilenas: Curraleiro, Crioulo Lageano y Junqueira disponibles en la granja Parque perteneciente a Embrapa Recursos Geneticos y Biotecnologia, Brasilia, DF y de los Pantaneiros ubicados en el norte del Pantanal, pertenecientes a la finca Promissao, Pocone, MT. Fueron analizados los cariotipos de 29 machos a traves de su tipo morfologico de cromosoma Y, submetacentrico o acrocentrico, tipos estos considerados como marcadores para las subespecies taurinas y cebuinas, respectivamente. El resultado mostro que, dentro de los seis sementales Curraleiros evaluados, cuatro presentaron Y de cebu (acrocentrico) y dos de taurino (submetacentrico), sugiriendo contaminacion racial por Cebu. Sin embargo, todos los Pantaneiros analizados presentaron exclusivamente cromosoma Y de Cebu (acrocen-trico), mientras que los bovinos Crioulo Lageano y Junqueira presentaron solo Y submetacentrico, confirmando su origen taurino. EnglishThe present work is a preliminary cytogenetic study carried out on 29 males of the Brazilian breeds Curraleiro, Crioulo Lageano, Junqueira and Pantaneiro, available at Embrapa Genetic Resources & Biotechnology, Brasilia, DF and Promissao farm, Pocone, MT. The objective was to investigate their Y chromosome morphology, whether submetacentric or acrocentric, consi-dered as markers of the taurine and zebuine subspecies, respectively. The results showed that of the six Curraleiro animals analyzed, four had an acrocentric and two had a submetacentric Y chromosome, indicating contamination by zebu breeds. All Pantaneiro bulls analyzed had exclusively zebuine (acrocentric) Y chromosome. On the other hand, the Crioulo Lageano and Junqueira bulls had submetacentric Y chromo-somes, indicating their taurine origin.

The objectives of this work were to investigate the genetic structure of the Brazilian hair sheep breeds and to determine the origin of the Santa Inês breed. Molecular similarity was determined using Randomly Amplified Polymorphic DNA - Polymerase Chain Reaction markers in 238 individuals from five naturalized sheep breeds: Santa Inês (48 animals), Rabo Largo (48), Somali (48), Morada Nova (48) and Bergamasca (46), collected in Goiás, Sergipe, Bahia, and Ceará States as well as in the Federal District. Fifty-four loci were selected from 19 primers, after a pilot test using 140 primers. Qualitative analyses indicate diagnostic markers for all breeds. All breeds were significantly different from each other. Interbreed differences were explained by 14.92% of the total variation. Santa Inês clustered with Bergamasca (97% bootstrap) and with Rabo Largo, composing the third member of the group (81% bootstrap) while Morada Nova and Somali breeds clustered separately. Each breed should be considered as a separate management and conservation unit, and special care should be taken with Rabo Largo, Morada Nova and Somali breeds, represented by small herds in Brazil. ___________________________________________________________________________________ RESUMO Os objetivos deste trabalho foram identificar a origem racial de ovinos Santa Inês e avaliar a unicidade das populações das principais raças naturalizadas brasileiras de ovinos deslanado. Foi realizado um estudo dos padrões de semelhança molecular a partir de marcadores RAPD-PCR, utilizando-se 238 indivíduos dos Estados de Goiás, Sergipe, Bahia, e Ceará assim como do Distrito Federal, distribuídos entre as raças Santa Inês (48 animais), Bergamácia (46), Rabo Largo (48), Morada Nova (48) e Somali (48). Após triagem com 140 primers, foram selecionados 54 locos a partir de 19 primers e todas as raças apresentaram marcadores específicos. Análises qualitativas mostraram a presença de marcadores diagnóstico-específicos para todas as raças. As diferenças inter-raciais foram significativas e responsáveis por 14,92% da variação total observada. Na análise de agrupamento, a raça Santa Inês ficou próxima à Bergamácia (com 97% de valor bootstrap). A raça Rabo Largo apresentou maior similaridade com este grupo (com 81% bootstrap) do que as raças Morada Nova e Somali. Cada raça deve ser considerada como unidade de conservação e manejo, especialmente as raças Rabo Largo, Morada Nova e Somali, as quais apresentam as menores populações no País.

The objective of this study was to verify the genetic diversity between and within seven populations of Moxotó goat (n = 264) from the States of Pernambuco, Paraíba and Rio Grande do Norte, using RAPD (Random Amplified Polymorphic DNA). Moxotó, as well as other naturalized breeds, suffers genetic losses due to the indiscriminate miscegenation with breeds raised in the Northeast Region of Brazil. The genetic characterization of these genetic resources is essential to conservation and breeding programs. DNA was extracted from lymphocytes using a non-organic protocol. The 16 primers used were selected from 120 decamer oligonucleotide primers and generated 56 polymorphic bands. The analysis of molecular variance (AMOVA) showed that the greater part of total genetic variability (71.55%) was due to differences between individuals within populations, while 21.21% was among populations. The analysis of variance among the pairs of populations demonstrated that the populations located in Floresta, PE x Angicos, RN presented a smaller value of intrapopulational differentiation (8.9%), indicating low genetic variability among them. Nei's genetic distances varied between 0.0546 and 0.1868 in the populations. The dendrogram generated showed that the Canindé breed, used as outgroup, clustered with the populations of Moxotó, indicating a possible common origin of the naturalized goat breeds. O objetivo deste estudo foi verificar a diversidade genética entre e dentro de sete populações de cabras Moxotó (n = 264) dos Estados de Pernambuco, Paraíba e Rio Grande do Norte, usando a técnica de RAPD (Poliformismo de DNA Amplificados ao Acaso). A raça Moxotó, assim como outras naturalizadas, sofre grande erosão genética devido à miscigenação indiscriminada com outras raças existentes na Região Nordeste. A caracterização genética desta raça é essencial para programas de conservação e melhoramento. Os marcadores moleculares são uma ferramenta útil na estimativa da diversidade genética de diferentes populações. O DNA foi extraído a partir de linfócitos utilizando-se um protocolo não orgânico. Os 16 primers utilizados foram selecionados a partir de 120 oligonucleotídeos e geraram 56 bandas polimórficas. A análise de variância molecular (AMOVA) demonstrou que a maior parte da variabilidade genética total (71,55%) ocorreu em virtude das diferenças entre indivíduos dentro das populações, enquanto 21,21% ocorriam entre as populações. A análise da variância entre os pares de populações demonstra que as populações de Floresta, PE x Angicos, RN apresentam o menor valor de diferenciação interpopulacional (8,9%), indicando menor variabilidade entre elas. A distância genética de Nei variou entre 0,0546 e 0,1868 nas populações. O dendrograma gerado demonstra que a raça Canindé, utilizada como outgroup, agrupa-se com as populações de Moxotó, indicando a possível origem comum das raças naturalizadas.

Brazil has various species of domestic animals, which developed from breeds brought by the Portuguese settlers soon after their discovery. For five centuries, these breeds have been subjected to natural selection in specific environments. Today, they present characteristics adapted to the specific Brazilian environmental conditions. These breeds developed in Brazil are known as “Crioulo,” “local,” or naturalized. From the beginning of the 20th century, some exotic breeds, selected in temperate regions, have begun to be imported. Although more productive, these breeds do not have adaptive traits, such as resistance to disease and parasites found in breeds considered to be “native.” Even so, little by little, they replaced the native breeds, to such an extent that the latter are in danger of extinction. In 1983, to avoid the loss of this important genetic material, the National Research Center for Genetic Resources and Biotechnology (Cenargen) of the Brazilian Agricultural Research Corporation (Embrapa) decided to include conservation of animal genetic resources in its research program Conservation and Utilization of Genetic Resources. Until this time, they were only concerned with conservation of native plants. Conservation has been carried out by various research centers of Embrapa, universities, state research corporations, and private farmers, with a single coordinator at the national level, Cenargen. Specifically, conservation is being carried out by conservation nuclei, which are specific herds in which the animals are being conserved, situated in the habitats where the animals have been subjected to natural selection. This involves storage of semen and embryos from cattle, horses, buffaloes, donkeys, goats, sheep, and pigs. The Brazilian Animal Germplasm Bank is kept at Cenargen, which is responsible for the storage of semen and embryos of various breeds of domestic animals threatened with extinction, where almost 45,000 doses of semen and more than 200 embryos exist presently. An important challenge for this program is to make the different segments of society realize the importance of the conservation of animal genetic resources.

Background Brazil holds the largest commercial cattle populations worldwide. Local cattle breeds can be classified according to their origin, as exotic or Creole. Exotic breeds imported in the last 100 years, both zebuine and taurine, currently make up the bulk of the intensively managed populations. Locally adapted Creole breeds, originated from cattle introduced by the European conquerors derive from natural selection and events of breed admixture. While historical knowledge exists on the Brazilian Creole breeds very little is known on their genetic composition. The objective of this study was to assess the levels of genetic diversity, phylogenetic relationships and patterns of taurine/zebuine admixture among ten cattle breeds raised in Brazil. Results Significant reduction of heterozygosity exists due both to within-population inbreeding and to breed differentiation in both subspecies (taurine and zebuine). For taurine breeds the number of markers that contribute to breed differentiation is larger than for zebuine. A consistently similar number of alleles was seen in both subspecies for all microsatellites. Four Creole breeds were the most genetically diverse followed by the zebuine breeds, the two specialized taurine breeds and the Creole Caracu. Pairwise genetic differentiation were all significant indicating that all breeds can be considered as genetically independent entities. A STRUCTURE based diagram indicated introgression of indicine genes in the local Creole breeds and suggested that occasional Creole introgression can be detected in some Zebuine animals. Conclusion This study reports on a comprehensive study of the genetic structure and diversity of cattle breeds in Brazil. A significant amount of genetic variation is maintained in the local cattle populations. The genetic data show that Brazilian Creole breeds constitute an important and diverse reservoir of genetic diversity for bovine breeding and conservation. The genetic data was able to shed light on a number of issues related to the local breeds origin and structure. The Brazilian Creole breeds are all important and viable targets for conservation for they display peculiar traits both phenotypic and of cultural and historical nature that deserve conservation efforts.

In Brazil, outbreaks caused by the stable fly (Stomoxys calcitrans) are associated with sugarcane mill activities near livestock properties. The natural seasonality of this fly shows population peaks during hot and humid months of the year. To alleviate the effects caused by this pest, rural producers and sugarcane mills have widely adopted the chemical control, however its intensive use has led to the selection of resistant individuals. Therefore, the objective of the present study was to know the population dynamics and to evaluate the occurrence of the kdr-his mutation as a mechanism of pytrhroid-resistance of the stable fly to pyrethroid insecticides occurs due to. For the study, reflective traps were installed, which were collected and exchanged each time. seven days, in which specimens were identified and counted. The population dynamics of stable flies in sugarcane mills in the municipalities of Pereira Barreto (PB) and Sud Mennucci (SM), São Paulo presented different frequencies and the population peaks occurred in January, May/June and October/November. Thus, a close relationship was found between the control actions performed in the fertigated crops, in the composting yard and the quality in the management of animal production residues, and population abundance of the pest. The study to assess the occurrence of the kdr-his mutation in stable flies by allelespecific PCR was carried out in the municipalities of Buritizal (BTZ), Nova Independência (NI), Pereira Barreto (PB) and Sud Mennucci (SM), totaling 200 individuals. The total frequency of the kdr-his allele was 0.263, while the total genotypic frequency obtained was 0,480 for susceptible homozygote, 0,515 for heterozygote and 0,005 for kdr-his homozygote. The results showed that the kdr-his mutation is present in sugarcane mills in the state of São Paulo. No Brasil, surtos causados pela mosca-dos-estábulos (Stomoxys calcitrans) estão associados a usinas sucroalcooleiras adjacentes a propriedades pecuárias. A sazonalidade natural desta mosca mostra picos populacionais durante os meses quentes e úmidos do ano. Para amenizar os efeitos causados por esta praga produtores rurais e usinas de cana-de-açúcar têm adotado amplamente o controle químico, porém o uso intensivo tem levado à seleção de indivíduos resistentes. Portanto, o objetivo do presente estudo foi conhecer a dinâmica populacional e avaliar a ocorrência da mutação kdr-his, associada à resistência da mosca-dos-estábulos aos inseticidas piretroides. O estudo da dinâmica populacional da mosca-dosestábulos foi realizado no município de Pereira Barreto (PB) e Sud Mennucci (SM) durante 2018 e 2019. Para o estudo foram instaladas armadilhas reflexivas, as quais eram recolhidas e trocadas a cada sete dias, nas quais os espécimes eram identificados e contados. A dinâmica populacional da mosca-dos-estábulos nas usinas sucroenergéticas nos municípios de Pereira Barreto (PB) e Sud Mennucci (SM), São Paulo, apresentou frequências diferentes e os picos ocorreram nos meses de janeiro, maio/junho e outubro/novembro. Deste modo foi constatada uma estreita relação entre as ações de controle desempenhadas nas lavouras fertirrigadas, no pátio de compostagem e a qualidade no manejo dos resíduos da produção animal e a densidade populacional da praga. O estudo para avaliar a ocorrência da mutação kdr-his por PCR alelo-específico foi realizado nos municípios de Buritizal (BTZ), Nova Independência (NI), Pereira Barreto (PB) e Sud Mennucci (SM), totalizando 200 indivíduos. A frequência total do alelo kdr-his foi de 0,263, já a frequência genotípica total obtida foi 0,480 para homozigoto susceptível, 0,515 para heterozigoto e 0,005 para homozigoto kdr-his. Os resultados evidenciam que a mutação kdr-his está presente nas populações de mosca-dos-estábulos em usinas do estado de São Paulo.