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The aim of this study was to evaluate the effect of the polymorphic FecGE allele on reproductive traits in Santa Inês and Morada Nova ewes. The traits evaluated were as follows: total progeny weights at birth (PWB) and weaning (PWW) and progeny survival rates at birth (PSRB) and weaning (PSRW). A total of 389 animals, belonging to two Santa Inês herds and one Morada Nova herd, were genotyped. There was a difference between the averages for all the traits studied regarding type of parturition, herd/breed, genotype/herd, and genotype/type of parturition. For each additional progeny, if the female was FecGE/E, the PWB decreased by 1.02 kg and the PWW by 3.16 kg, also with a 0.04% reduction in PSRB and no change in PSRW. If the female was FecGE/+, the reduction in PWB was 0.24 kg, with an increase in PSRW by 0.11%, but no change in PWW and PSRB. In general, these results demonstrate that FecG+/+ females have a better ability to increase their number of progenies without reducing PWB and PWW (also similar to FecGE/+). Thus, it is suggested that further studies on the association between the traits of interest and candidate genes in sheep should be carried out so that the regions which have the greatest effect on the expression of these traits are actually identified. It was not possible to verify the effect of the FecGE allele on the PWB, PWW, PSRB, and PSRW in these Morada Nova and Santa Inês herds.

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Optimization of DNA collection for National gene bank and conservation programs requires information on spatial and genetic distribution of animals countrywide. The relationship between genetic and geographic distances were examined in 8 Brazilian horse breeds (Baixadeiro, Crioulo, Campeiro, Lavradeiro, Marajoara, Mangalarga Marchador, Pantaneiro and Puruca) using Single Nucleotide Polymorphism markers and collection point locations. Mantel correlations, Genetic Landscape Shape Interpolation, Allelic Aggregation Index Analyses and Spatial autocorrelation tests indicated a nonrandom distribution of horses throughout the country. Minimum collection distances for the national Gene Bank should be 530km, with clear divisions seen in genetic structure of horse populations in both North/South and East/West directions. Comparing Pantaneiro and North/Northeastern breeds, physical distance is not necessarily the defining factor for genetic differentiation. This should be considered when sampling these local breeds. These data can help optimise GenBank collection routines and conservation strategies for these breeds.

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The study aimed to verify the influence of the FecGE mutation in superovulated ewes and to evaluate the probability of logistic models to determine the response capacity of these ewes to superovulatory treatment. Santa Inês ewes (n = 29) were genotyped for the FecGE mutation and separated for their genotype group in carriers of the mutant E allele (FecGE/E, FecG+/E) and non-carrier (FecG+/+) alleles. The ewes underwent hormonal treatment for superovulation. Aside from the genotypes, variables included in the statistical model were reproductive status (empty, early lactation, or late lactation), age (> or < 6 years), and number of births (nulliparous, primiparous, multiparous). The carriers of the mutation could be discriminated from the non-carriers based on the number of corpora lutea, rate of frozen embryos, and fecundity. Recovery rate was significantly higher (P < 0.05) in FecGE/E (94.31%) compared to FecG+/E (63.15%) and FecG+/+ (61.90%) (P < 0.05), whereas fecundity rate of FecG+/+ ewes (50.76%) was significantly higher than FecG+/E (18.96%) and FecGE/E (32.53%) (P < 0.05). We determined in this study that the response to superovulation and embryo production can be discriminated between FecGE/E and FecG+/E ewes in relation to the FecG+/+ genotype. Logistic models that included reproductive status and mutation, or reproductive status and age, or reproductive status and number of births were effective in predicting the response to superovulatory treatment.

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Creole sheep represent a strategic genetic resource for populations living in marginal areas under financial restrictions on the American continent. Six Colombian sheep breeds (two wool (BCL-Boyacá and NCL-Nariño, 12 and 14 samples) and four hair (OPCE-Ethiopian, 54 samples; OPCS-Sudan, 74 samples; OPCP-Pelibeuy, 59 samples; OPCW-Wayúu, 24 samples) were genotyped using the Illumina Ovine SNP50 BeadChip. Data was also included from international 44 breeds from International Sheep Genomics Consortium (ISGC) and from data published in previous a previous work on the Caribbean and African breeds. Although geographically separated, wool (NCL, BCL) and hair types (OPCE, OPCS, OPCW) presented little genetic differentiation (FST 0.05) at a global level but several groups of animals separated suggesting local clustering due to geographical isolation. The OPCP underwent a recent crossing with Mexican Pelibuey, explaining its differentiation. Findings in this work such as the proximity to West African Djallonké (WAD) and Barbados Black Belly (BBB), suggest different introductions of African type animals from the Caribbean region on a pre-existing genetic basis formed by animals deriving from the first importations coming from Europe in colonial times. As expected, Colombian wool breeds showed, in particular in Admixture software results, a greater genomic component in common with European breeds and in particular with Iberian ones (Churra). This study provides a basis for future research into the genetic diversity within and between the Colombian sheep breeds analysed, and scientific data for policy decisions on Farm Animal Genetic Resources (FAnGR).

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Since domestication, horse breeds have adapted to their environments and differentiated from one another. This paper uses two methods to detect selection signatures in 23 horse breeds, eight of which are Brazilian (610 animals), both cold-blooded and warm-blooded, from temperate and tropical regions. These animals were genotyped using the GGP Equine BeadChip and we analysed the data by Principal Component Analysis (PCA). The samples were separated into groups based on their geographical area of origin and PCA results studied. The genomic regions under selection were detected by hapFLK and PCAdapt methodologies, identifying six regions under selection with at least one Brazilian horse breed. These regions contain genes associated with heat tolerance, skin colour, body size, energy production/metabolism, genes involved in protein degradation/turnover/DNA repair, genes reducing the impact of oxidative stress/cellular repair, and transcriptional regulation. This work confirmed LCORL and NCAPG gene regions in previous studies associated with body size on Equine Chromosome Autosome 3 (ECA3). On the same ECA3, a region implicating genes linked to coat colour was identified, also previously related to heat stress. Regions with genes coding heat shock proteins were found on ECA1 and 2, and many candidate genes for oxidation-reduction which are a natural response to heat stress. However, a larger sample size and whole-genome SNPs are needed to understand better and identify new candidate regions as well as their functional relation with heat tolerance.

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Small ruminant lentiviruses (SRLVs) affect sheep and goats worldwide. The major gene related to SRLV infections is the Transmembrane Protein Gene 154 (TMEM154). We estimated the haplotype frequencies of TMEM154 in the USA (USDA-ARS) and Brazil (Embrapa) Gene Banks by using two different SNP genotyping methodologies, FluidigmTM and KASPTM. We also genotyped the ZNF389_ss748775100 deletion variant in Brazilian flocks. A total of 1040 blood samples and 112 semen samples from 15 Brazilian breeds were genotyped with Fluidigm for the SNP ZNF389_ss748775100 and 12 TMEM154 SNPs. A total of 484 blood samples from the Santa Inês breed and 188 semen samples from 14 North American sheep breeds were genotyped with KASP for 6 TMEM154 SNPs. All the Brazilian samples had the "I/I" genotype for the ZNF389_ss748775100 mutation. There were 25 TMEM154 haplotypes distributed across the Brazilian breeds, and 4 haplotypes in the US breeds. Haplotypes associated with susceptibility were present in almost all breeds, which suggests that genetic testing can help to improve herd health and productivity by selecting non-susceptible animals as founders of the next generations. Fluidigm and KASP are reliable assays when compared with Beadchip arrays. Further studies are necessary to understand the unknown role of TMEM154 mutations, host-pathogen interaction and new genes associated with the clinical condition.

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Among the animal species first introduced in Brazil during the country's discovery, horses (Equus caballus) stand out because of their evolutionary history and relationship with humans. Among the Brazilian horse breeds, the Pantaneiro draws attention due to its adaptative traits. Blood samples of 116 Pantaneiro horses were divided into six populations based on their sampling location, aiming to identify the existence of genetic structure and quantify genetic diversity within and between them. Populations were compared to elucidate genetic variability and differentiation better and assess the impact of Pantanal's natural geographic barriers on gene flow between populations. Data from the GGP Equine BeadChip (Geneseek-Neogen, 65.157 SNPs) was used to assess basic diversity parameters, genetic distance (FST), principal component analysis (PCA), and population structure (ADMIXTURE) for the sampled animals. Mantel test was also performed to investigate the correlation between the populations' genetic and geographic distances. Results showed high genetic variability in all populations, with elevated levels of admixture in their structure. High levels of admixture make it challenging to establish a racial pattern and, consequently, populations within the breed, being that only one of the populations differentiated itself from the others. No significant correlations between genetic and geographic distances were observed, indicating that environmental barriers did not hinder gene flow between populations, and neither farmers' selection practices might have change breed genetic composition significantly. Low genetic distance and similar heterozygosity values were observed among populations, suggesting strong genetic proximity and low differentiation. Thereby, the Pantaneiro breed does not exhibit genetic subpopulations and could be considered, for conservation purposes, a single big population in the Panatnal region. This study will support sampling strategies for National genebank.

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This study was conducted to characterize the morphology and morphometry of follicles containing multiple oocytes (MOFs) and determine the association with the FecGE mutation in Santa Inês ewes. Based on the genotypes, 65 ewes were characterized as being homozygous wild-type (n = 25; FecG+/+), heterozygous mutant (n = 27, FecG+/E), and homozygous mutant (n = 13, FecGE/E). The variables evaluated were follicle developmental stage, number of oocytes per follicle, morphology, and morphometry of MOFs. The FecGE mutation did not affect the frequency of MOFs (P > 0.05) (3.0 % in FecG+/+; 3.3 % in FecG+/E; and 3.5 % in FecGE/E). The greater viability (P < 0.05) of MOFs was identified in transitory stage of the FecGE/E (95.0 %) and FecG+/E (90.9 %) when compared to the FecG+/+ genotype (73.3 %). Furthermore, the morphology of transitory follicles with two oocytes was the variable and when evaluated was the most reliable determinant for predicting which ewes had an FecGE mutation. In conclusion, the FecGE mutation did not affect the frequency of MOFs. The ewes with FecGE mutation had a greater frequency of morphologically normal MOFs in the transitory stage. Furthermore, the ewes with the FecGE mutation had a greater likelihood of having MOFs containing two morphologically normal oocytes.

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There are few animal germplasm/gene bank collections in Brazil, and basic studies are needed to attend the future internal and external demands from international partners. The aim of this work was to validate a "proof of concept" that integrates spatial (georeferenced data) and genetic data regarding the local of origin from 3518 DNA samples from 17 different genetic groups or breeds of sheep in the Brazilian Germplasm bank. Spatialisation shows that not all genetic groups have samples in the bank, and collection is concentrated in the conservation nuclei spread nationwide. Only 21% of states with a specific breed have samples in the gene bank. The mean number of animals sampled per collection was 32, while the mean distance travelled to collect samples was 262 km from the conservation nuclei. For example, the Brazilian Somali were only collected in the conservation nucleus in Ceará State. No samples were collected to date for the Cariri breed, which is recognised by the Brazilian Ministry of Agriculture. Only two farms and one breed in the bank are from the northern region. Of the 27 states, there are samples in the gene bank of sheep from 13, so several states have no samples, requiring collection from herds outside the official system of conservation to make sure that studies using this germplasm realised are not biased. Significant genetic differences are seen above 332 km, which should guide future sampling efforts. Suggestions are given for improving the quantity, quality and diversity of samples in the gene bank.

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Cattle breeding routinely uses crossbreeding between subspecies (Bos taurus taurus and Bos taurus indicus) to form composite breeds, such as Brangus. These composite breeds provide an opportunity to identify recent selection signatures formed in the new population and evaluate the genomic composition of these regions of the genome. Using high-density genotyping, we first identified runs of homozygosity (ROH) and calculated genomic inbreeding. Then, we evaluated the genomic composition of the regions identified as selected (selective sweeps) using a chromosome painting approach. The genomic inbreeding increased at approximately 1% per generation after composite breed formation, showing the need of inbreeding control even in composite breeds. Three selected regions in Brangus were also identified as Angus selection signatures. Two regions (chromosomes 14 and 21) were identified as signatures of selection in Brangus and both founder breeds. Five of the 10 homozygous regions in Brangus were predominantly Angus in origin (probability >80%), and the other five regions had a mixed origin but always with Brahman contributing less than 50%. Therefore, genetic events, such as drift, selection, and complementarity, are likely shaping the genetic composition of founder breeds in specific genomic regions. Such findings highlight a variety of opportunities to better control the selection process and explore heterosis and complementarity at the genomic level in composite breeds.

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The Monteiro is a feral pig found in the Brazilian Pantanal ecosystem. The goal of this research is to generate data and knolewdge related to animal populations wich can be used for management and development of an in vitro conservation program for animal resourses at Pantanal ecosystem. The present study evaluated animals sampled from 10 distinct locations within the region, using 19 microsatellite markers (N = 189) and the control region of mitochondrial DNA (mtDNA) (N = 392). Low genetic differences were found between populations with the microsatellite data. The FST range was between 0.009 and 0.063 (p-value < 0.05). The Mantel test corroborated with previous results, as low correlations between genetic and geographic distances were observed (r2 = 0.2309, p = 0.06). Bayesian analysis for genetic structure identification placed the Monteiro pigs into three main clusters (MOB, Pop 1 and all others Pantanal populations). Most of the Monteiro pigs share a single European haplotype as seen by mtDNA analyses. This haplotype is not exclusive, as it is shared with other swine populations (commercial and other locally adapted breeds). Monteiro populations from different geographic locations within Pantanal are not isolated and can be considered as a large unique population. Since animals roam freely to seek food and water, or even due to seasonal flooding of their habitat, the Monteiro populations presented absence of major genetic structure and evidence of high gene flow. These results can be used to create a management plan and in situ and ex situ conservation program for conservation and use of the Monteiro breed in the Pantanal ecosystem.

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Spinner dolphins (Stenella longirostris, Gray 1828) are widely distributed in tropical waters around the world. Although they occur in large, pelagic groups in the Eastern Tropical Pacific, elsewhere in the Pacific they are found in small and genetically isolated populations associated with islands. This species is considered to be "Least Concern" (LC) by the World Conservation Union (IUCN). To assess genetic diversity and population structure of an island-associated population in the South Atlantic Ocean we surveyed 162 spinner dolphins throughout the Fernando de Noronha Archipelago of the northeast coast of Brazil using ten microsatellite loci and sequencing a 413-bp section of the mitochondrial DNA (mtDNA) control region. Eleven mtDNA haplotypes were identified and haplotype diversity (h) and nucleotide diversity (π) were 0.3747 and 0.0060, respectively. Median-Joining Network revealed the presence of two very divergent haplotypes and F-statistics indicated some heterogeneity between two sampling years. All microsatellite loci were polymorphic (Ho: 0.767; He: 0,764) but, revealed no detectable substructure. We also compared the mtDNA haplotypes from Noronha to 159 haplotypes representing 893 individuals from 14 locations worldwide. We found that the two common haplotypes from the Fernando de Noronha Archipelago were absent in all other populations. These comparisons showed that Noronha spinner dolphins are likely more differentiated than other island populations, suggesting that they form societies with strong site fidelity mediated by females.

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Based on ovarian and follicular variables, there was determination of ewes with different FecGE genotypes. Based on the FecGE genotype, 65 Santa Inês ewes were assigned to three experimental groups: homozygous wild-type (n = 25; FecG+/+), mutant heterozygous (n = 27; FecG+/E) and mutant homozygous (n = 13; FecGE/E). The ewe's ovaries were weighed and measured, then the follicles (oocyte, nucleus and nucleolus) were histologically evaluated for morphometry and morphology. Morphologically normal follicles, in the primordial and transitional stages, explained 70.18% of the variability morphological characteristics between mutant and wild-type ewes. Conducting the morphometric evaluation resulted in a more precise determination of the genotype groups when there was assessment of the primordial and secondary follicular developmental stages. The diameter of the oocyte and the oocyte nucleus of the primordial follicles explained 36.76% of the variability in follicular morphology between ewes with the mutation and those with the wildtype group. Similarly, the core diameter of oocytes in secondary follicles explained 10.63% of the variability in follicular morphology among FecGE/E, FecG+/E and FecG+/+ ewes. Thus, morphologically normal follicles in the primordial and transitional stages of development are the variables that allow for a more precise differentiation of Santa Inês ewes with the FecGE mutation. These variables may be evaluated to make more efficient the adoption of biotechniques that when conducted there is utilisation of follicles in the initial developmental stages as a physiological basis for classifying whether specific follicles are useful when conducting the techniques.

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Human migration and trade facilitated domesticated livestock movement, gene flow and development of diverse populations upon which agriculture is based. In addition, varying USA ecological conditions has led to a diverse set of livestock populations to utilize. Quantifying genetic diversity of these populations is incomplete. This paper quantifies genetic diversity captured by the National Animal Germplasm Program and explores genetic structure and differences among 19 pig populations (feral populations from Pacific islands, continental US, and Chinese breeds) using 70,231 SNP from 500 animal samples. Among continental US breeds Fis was consistently low suggesting genetic variability is sufficiently available for breeders to use. A unique population structure using principal component analysis illustrated clear distinctions between Duroc, Yorkshire, Hampshire, breeds of Chinese origin, and feral Pacific Island populations were identified. Five Y chromosome haplotypes were evaluated and demonstrated migration patterns from European, central Asia, and potentially Polynesian waves of gene flow. Quantifying diversity and potential origin of Pacific populations provides insight for future uses, and the need for preservation. Viewing gene bank holdings in context of diversity measures we found a lack of inbreeding within breeds, suggesting the collection represents a wide sampling of individual breeds.

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Western hemisphere goats have European, African and Central Asian origins, and some local or rare breeds are reported to be adapted to their environments and economically important. By-in-large these genetic resources have not been quantified. Using 50 K SNP genotypes of 244 animals from 12 goat populations in United States, Costa Rica, Brazil and Argentina, we evaluated the genetic diversity, population structure and selective sweeps documenting goat migration to the "New World". Our findings suggest the concept of breed, particularly among "locally adapted" breeds, is not a meaningful way to characterize goat populations. The USA Spanish goats were found to be an important genetic reservoir, sharing genomic composition with the wild ancestor and with specialized breeds (e.g. Angora, Lamancha and Saanen). Results suggest goats in the Americas have substantial genetic diversity to use in selection and promote environmental adaptation or product driven specialization. These findings highlight the importance of maintaining goat conservation programs and suggest an awaiting reservoir of genetic diversity for breeding and research while simultaneously discarding concerns about breed designations.

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Abstract Background: The lack of information on population structure is one of the main obstacles to develop breeding and conservation programs for animal genetic resources. Objective: To characterize the population structure of Crioula Lageana cattle breed (Bos taurus) in order to assess its genetic diversity. Methods: Database with information of 1,638 Crioula Lageana animals, collected during 38 years, was analysed using the ENDOG v.4.4 program. Results: Effective population size ranged from 72.53 in complete generations to 143.90 in maximum generations. Inbreeding and Average Relatedness coefficients were 0.34 and 0.91%, respectively. The effective number of founders and ancestors were 29 and 28 animals, respectively, and only ten ancestors were responsible for 50% of the genetic variability of the whole population. The average generation interval was 5.84 years in the paternal line and 7.70 in the maternal one. Wright´s F statistics indicated low genetic distances between subsets in relation to the total population (Fst = 0.0015), between individuals with respect to their subpopulation (Fis = -0.0027), and between individuals in relation to the total population (Fit = -0.0012). Conclusion: Analysis of the population indicated that, despite the small number of animals with known parentage and considerable loss of genetic variability by the constant use of a few sires, and same value of number of founders and ancestors, the population showed good genetic management, low inbreeding, low genetic differentiation among subpopulations, and probably adequate effective population size for breed preservation.

Resumen Antecedentes: La falta de información sobre estructura poblacional es una de las principales barreras para el desarrollo de programas de mejoramiento genético y conservación de los recursos zoogenéticos. Objetivo: Caracterizar la estructura poblacional de la raza bovina Crioula Lageana (Bos taurus) para evaluar su diversidad genética. Métodos: Una base de datos con información de 1.638 animales Crioula Lageana (Bos taurus), recogidos durante 38 años, fue analizada utilizando el programa ENDOG v.4.4. Resultados: El tamaño efectivo de la población varió de 72,53 en las generaciones completas a 143,90 en las generaciones máximas. La endogamia y la relación media de los coeficientes fue 0,34 y 0,91%, respectivamente. El número efectivo de fundadores y antepasados fue de 29 y 28 animales respectivamente, y sólo diez antepasados fueron responsables del 50% de la variabilidad genética de la población. El intervalo promedio de generación fue de 5,84 años en la línea paterna y de 7,70 en la línea materna. El índice estadístico de Wright's F indica una baja distancia genética entre los subconjuntos en relación con la población total (Fst = 0,0015), entre los individuos con respecto a su subpoblación (Fis = -0,0027), y entre los individuos en relación con la población total (Fit = -0,0012). Conclusión: El análisis de la población indica que a pesar del pequeño número de animales con origen conocido y la considerable pérdida de variabilidad genética por el uso constante de pocos toros y el mismo valor del número de fundadores y antepasados, la población mostró un buen manejo genético, baja endogamia, baja diferenciación genética entre las subpoblaciones y probablemente un tamaño efectivo adecuado de la población.

Resumo Antecedentes: A falta de informações sobre a estrutura da população está entre os principais obstáculos ao desenvolvimento de programas de melhoramento e conservação de recursos genéticos animais. Objetivo: Caracterizar a estrutura populacional da raça bovina Crioula Lageana (Bos taurus) para acessar a diversidade genética da raça. Métodos: Banco de dados com informação de 1.638 animais Crioula Lageana, recolhidos durante 38 anos, foi analisado utilizando EndoG v.4.4. Resultados: O tamanho efetivo populacional variou de 72,53 nas gerações completas para 143,90 nas gerações máximas. Coeficientes de Endogamia e Relação foram 0,34 e 0,91%, respectivamente. O número efetivo de fundadores e ancestrais foram 29 e 28 animais, respectivamente, sendo que apenas dez ancestrais foram responsáveis por 50% da variabilidade genética de toda a população. O intervalo de gerações foi de 5,84 anos para linha paterna e 7,70 para linha materna. As estatísticas F de Wright indicaram uma pequena distância genética das subpopulacoes entre os subgrupos em relação à população total (FST = 0,0015), entre os indivíduos em relação à sua subpopulação (FIS = -0,0027) e entre indivíduos em relação à população total (Fit = -0,0012). Isto indica uma baixa diferenciação genética na população estudada. Conclusão: A análise populacional indicou que, apesar do número pequeno de animais com ascendência conhecida e considerável perda de variabilidade genética pelo uso constante de alguns touros e mesmo valor do número de fundadores e antepassados, a população mostrou boa gestão genética, endogamia baixa, baixa diferenciação genética entre subpopulações e provavelmente adequado tamanho efetivo da população para a preservação da raça.

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Samples of 191 animals from 18 different Brazilian locally adapted swine genetic groups were genotyped using Illumina Porcine SNP60 BeadChip in order to identify selection signatures related to the monthly variation of Brazilian environmental variables. Using BayeScan software, 71 SNP markers were identified as FST outliers and 60 genotypes (58 markers) were found by Samßada software in 371 logistic models correlated with 112 environmental variables. Five markers were identified in both methods, with a Kappa value of 0.073 (95% CI: 0.011-0.134). The frequency of these markers indicated a clear north-south country division that reflects Brazilian environmental differences in temperature, solar radiation, and precipitation. Global spatial territory correlation for environmental variables corroborates this finding (average Moran's I = 0.89, range from 0.55 to 0.97). The distribution of alleles over the territory was not strongly correlated with the breed/genetic groups. These results are congruent with previous mtDNA studies and should be used to direct germplasm collection for the National gene bank.

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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.

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Abstract 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.

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The cachara (Pseudoplatystoma reticulatum) is a Neotropical freshwater catfish from family Pimelodidae (Siluriformes) native to Brazil. The species is of relative economic importance for local aquaculture production and basic biological information is under development to help boost efforts to domesticate and raise the species in commercial systems. The complete cachara mitochondrial genome was obtained by assembling Illumina RNA-seq data from pooled samples. The full mitogenome was found to be 16,576 bp in length, showing the same basic structure, order, and genetic organization observed in other Pimelodidae, with 13 protein-coding genes, 2 rNA genes, 22 trNAs, and a control region. Observed base composition was 24.63% T, 28.47% C, 31.45% A, and 15.44% G. With the exception of NAD6 and eight tRNAs, all of the observed mitochondrial genes were found to be coded on the H strand. A total of 107 SNPs were identified in P. reticulatum mtDNA, 67 of which were located in coding regions. Of these SNPs, 10 result in amino acid changes. Analysis of the obtained sequence with 94 publicly available full Siluriformes mitogenomes resulted in a phylogenetic tree that generally agreed with available phylogenetic proposals for the order. The first report of the complete Pseudoplatystoma reticulatum mitochondrial genome sequence revealed general gene organization, structure, content, and order similar to most vertebrates. Specific sequence and content features were observed and may have functional attributes which are now available for further investigation.

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