Iberian Breeds Research Articles

The global spread of Oriental Horses in the past 1,500 years through the lens of the Y chromosome

Since their domestication, horses have accompanied mankind, and humans have constantly shaped horses according to their needs through stallion-centered breeding. Consequently, the male-specific portion of the Y chromosome (MSY) is extremely uniform in modern horse breeds. The majority of stallions worldwide carry MSY haplotypes (HT) attributed to an only ~1,500-y-old, so-called, "Crown" haplogroup. The predominance of the Crown in modern horse breeds is thought to represent a footprint of the vast impact of stallions of "Oriental origin" in the past millennium. Here, we report the results of a fine-scaled MSY haplotyping of large datasets of patrilines comprising 1,517 males of 189 modern horse breeds, covering a broad phenotypic and geographic spectrum. We can disentangle the multilayered influence of Oriental stallions over the last few hundred years, exposing the intense linebreeding and the wide-ranging impact of Arabian, English Thoroughbred, and Coldblood sires. Iberian and New World horse breeds contain a wide range of diversified Crown lineages. Their broad HT spectrum illustrates the spread of horses of Oriental origin via the Iberian Peninsula after the Middle Ages, which is commonly referred to as the "Spanish influence." Our survey also revealed a second major historical dissemination of horses from Western Asia, attributed to the expansion of the Ottoman Empire. Our analysis shows that MSY analysis can uncover the complex history of horse breeds and can be used to establish the paternal ancestry of modern horse breeds.

Characterization of SNPs in meat quality-related genes in Argentine Coastal Creole pigs and their potential as a porcine genetic resource.

The Coastal Creole pigs in Argentina are predominantly found in the wild and can trace their lineage directly back to the Iberian breeds introduced by Spanish colonizers. They currently stand as the sole Creole breed in the country recognized by the FAO. However, there exists a dearth of studies assessing their genetic potential within the swine industry. Therefore, this study aimed to genetically characterize the meat quality of Coastal Creole pigs based on seven single nucleotide polymorphisms (SNPs) within the Ryr1, PRKAG3, MC4R, H-FABP, and CAST genes. A total of N = 158 samples were collected from specimens distributed along the coastal region. Our findings revealed all loci to exhibit polymorphism, underscoring the population's remarkable genetic diversity. Furthermore, a higher frequency of alleles favorable for the PRKAG3191I>V/200R>Q, MC4R1426A>G, CAST76872G>A, and Ryr11843C>T genes was observed, while alleles unfavorable predominated for H-FABP1811G>C and CAST638Ser>Arg. The results obtained in this research are highly encouraging, reflecting the genetic potential of these pigs to be utilized in swine production programs.

Explorando la genética de tres poblaciones de la raza Cerdo Pelón en México

The objective of this research was to carry out a molecular genetic characterization of three Hairless Pig (HP) breed populations located in México in the states of Nayarit, Oaxaca and Yucatán to identify variations, selection effects and population genetic relationships. From blood samples, a total of 163 animals from three populations of HP were successfully genotyped. Genotyped SNP data was employed to compute genetic diversity, population structure and landscape genetic analysis. The parameters of minor allele frequency (MAF), observed heterozygosity (Ho) and Wright’s fixation index (FIS) pointed out that the population of Nayarit is the one with the greatest genetic diversity (MAF: 0.362, Ho: 0.336, FIS: 0.061). Principal Component Analysis (PCA) and a Neighbor-joining phylogenetic tree analysis showed diversification among the three HP populations and pointed out a closer genetic relationship between the HP populations and the Iberian pig breed. The Admixture analysis showed as well common ancestry shared from commercial and Iberian breeds in the HP populations in different gradients. For the analysis of the relationships between geographic and genetic distances, Mantel test was computed and the results described a distribution pattern of the geographical locations along the genetic distances similar to the clustering pattern of the PCA and Neighbor-joining phylogenetic tree analysis. The results obtained manage to present the HP poor conservation state and the need to stablish a genetic conservation program meaning an effort to prevent the loss of a significant cultural, natural and genetic resource. Keywords: genetic diversity, landscape genetics, native breeds, genetic resources.

Connected impacts: combining migration tracking data with species distribution models reveals the complex potential impacts of climate change on European bee-eaters

Climate change is a key driver of biodiversity loss in multiple ecosystems, which can act at multiple stages of a species life- and annual cycle. Identifying where, when, and how these impacts may happen is key to understanding, and planning for, the population-level effects of climate change. This study assesses how climate change will impact the breeding and non-breeding areas of the European Bee-eater Merops apiaster, a long-distance migratory bird, by combining correlative species distribution models with recent tracking data to account for population connectivity between breeding and non-breeding sites. The three populations studied (Iberian, German, and Bulgarian) demonstrated different levels of exposure to climate change, as well as different patterns of connectivity. The Iberian breeding population showed high exposure to climate change in both its breeding and non-breeding sites, which may result in significant, interacting impacts on this population. In contrast, breeding populations in Germany are likely to benefit from climate change, both in their breeding and non-breeding range. Connectivity also varied; while most populations demonstrated extremely high connectivity between breeding and non-breeding sites, the Iberian population was substantially more behaviourally flexible, indicating there may be some adaptive capacity of this population to change non-breeding sites if some become less suitable due to climate change. Incorporating breeding and non-breeding areas into species distribution modelling highlights how the impacts of climate change may combine into multiplicative impacts across a species’ annual cycle, and how combining methodologies and data sources can provide greater insight into the impact of climate change on migratory species and, in turn, inform conservation action.

A meta-analysis of genetic and phenotypic diversity of European local pig breeds reveals genomic regions associated with breed differentiation for production traits

BackgroundIntense selection of modern pig breeds has resulted in genetic improvement of production traits while the performance of local pig breeds has remained lower. As local pig breeds have been bred in extensive systems, they have adapted to specific environmental conditions, resulting in a rich genotypic and phenotypic diversity. This study is based on European local pig breeds that have been genetically characterized using DNA-pool sequencing data and phenotypically characterized using breed level phenotypes related to stature, fatness, growth, and reproductive performance traits. These data were analyzed using a dedicated approach to detect signatures of selection linked to phenotypic traits in order to uncover potential candidate genes that may underlie adaptation to specific environments.ResultsAnalysis of the genetic data of European pig breeds revealed four main axes of genetic variation represented by the Iberian and three modern breeds (i.e. Large White, Landrace, and Duroc). In addition, breeds clustered according to their geographical origin, for example French Gascon and Basque breeds, Italian Apulo Calabrese and Casertana breeds, Spanish Iberian, and Portuguese Alentejano breeds. Principal component analysis of the phenotypic data distinguished the larger and leaner breeds with better growth potential and reproductive performance from the smaller and fatter breeds with low growth and reproductive efficiency. Linking the signatures of selection with phenotype identified 16 significant genomic regions associated with stature, 24 with fatness, 2 with growth, and 192 with reproduction. Among them, several regions contained candidate genes with possible biological effects on stature, fatness, growth, and reproductive performance traits. For example, strong associations were found for stature in two regions containing, respectively, the ANXA4 and ANTXR1 genes, for fatness in a region containing the DNMT3A and POMC genes and for reproductive performance in a region containing the HSD17B7 gene.ConclusionsIn this study on European local pig breeds, we used a dedicated approach for detecting signatures of selection that were supported by phenotypic data at the breed level to identify potential candidate genes that may have adapted to different living environments and production systems.

10 What Role Could Old/Heritage Genetics Play in Climate adaptation?

Abstract Creole or Criollo breeds descend directly from cattle introduced by the Spanish and Portuguese conquerors in the XVth century, being the only cattle breeds in the Americas that have endured 500 years of natural selection to local conditions. Their genetic background includes Iberian and African taurine breeds. This ancestry combined with local adaptations to a very wide variety of environments throughout all the continent created the wide spectrum of American Criollo breeds that we see today, from USA to the Patagonian region. Criollo cattle was the basis of colonial times livestock industry until they were displaced by more specialized European and cebuine type cattle breeds at the end of the 19th century. Efforts by local producers and research institutions helped to preserve Criollo populations and to avoid their extinction. Most of Criollo animals were relegated to marginal regions unsuitable for commercial breeds, which reinforced their ability to adapt to unfavorable environments. Their adaptation to different environments allowed the expression of high levels of genetic variability, being a source of hidden alleles of potential use in animal production and thus very important to study and preserve. The analysis of nuclear and cytoplasmic markers, such as SNP, microsatellites and mitochondrial DNA, has allowed estimations of genetic diversity, admixture events with other breeds, and the elucidation of genetic relationships within Criollo breeds and with European and African breeds. Criollo breeds differ considerably from each other, and most have their own identity or group with others from neighboring regions. These results indicate that Criollo breeds represent important reservoirs of cattle genetic diversity and that appropriate conservation measures should be implemented for these heritage breeds to minimize inbreeding and uncontrolled crossbreeding. Several studies have demonstrated that these animals can produce high quality meat, are more resistant to diseases and heat stress, and emphasize their high fertility, calving ease, longevity and ability to adapt to harsh environments, including arid regions. More studies are needed to elucidate the genetic basis of these traits. Properly managed, Criollo cattle “old genetics” can certainly be part of the solution to modern livestock production problems.

Ascertaining the genetic background of the Celtic-Iberian pig strain: A signatures of selection approach.

Celtic-Iberian pig breeds were majority in Spain and Portugal until the first half of the 20th century. In the 1990s, they were nearly extinct as a result of the introduction of foreign improved pig breeds. Despite its historical importance, the genetic background of the Celtic-Iberian pig strain is poorly documented. In this study, we have identified genomic regions that might contain signatures of selection peculiar of the Celtic-Iberian genetic lineage. A total of 153 DNA samples of Celtic-Iberian pigs (Spanish Gochu Asturcelta and Portuguese Bísara breeds), Iberian pigs (Spanish Iberian and Portuguese Alentejano breeds), Cinta Senese pig, Korean local pig and Cosmopolitan pig (Hampshire, Landrace and Large White individuals) were analysed. A pairwise-comparison approach was applied: the Gochu Asturcelta and the Bísara samples as test populations and the five other pig populations as reference populations. Three different statistics (XP-EHH, FST and ΔDAF) were computed on each comparison. Strict criteria were used to identify selection sweeps in order to reduce the noise brought on by the Gochu Asturcelta and Bísara breeds' severe population bottlenecks. Within test population, SNPs used to construct potential candidate genomic areas under selection were only considered if they were identified in four of ten two-by-two pairwise comparisons and in at least two of three statistics. Genomic regions under selection constructed within test population were subsequently overlapped to construct candidate regions under selection putatively unique to the Celtic-Iberian pig strain. These genomic regions were finally used for enrichment analyses. A total of 39 candidate regions, mainly located on SSC5 and SSC9 and covering 3130.5 kb, were identified and could be considered representative of the ancient genomic background of the Celtic-Iberian strain. Enrichment analysis allowed to identify a total of seven candidate genes (NOL12, LGALS1, PDXP, SH3BP1, GGA1, WIF1, and LYPD6). Other studies reported that the WIF1 gene is associated with ear size, one of the characteristic traits of the Celtic-Iberian pig strain. The function of the other candidate genes could be related to reproduction, adaptation and immunity traits, indirectly fitting with the rusticity of a non-improved pig strain traditionally exploited under semi-extensive conditions.

“Iberians are different”

Historically, Iberian breeds were considered the height of perfection, but with the development of the Thoroughbred (the embodiment of enlightened modernity) they increasingly were aligned with Spanish obsolescence. However, this dichotomy is too simple and often incorrect. As this paper illustrates, the Spanish Pure Breed itself is the outcome of a major modernization effort in the sixteenth century, linked to the Spanish colonial empire’s own early modernity. Furthermore, “modernizing” attempts continue to shape the breed as breeders and breed organizations attempt to meet the demands of the sport horse market, emulating the success of the modern sport horse breeds. Thus, as this paper argues, within complex temporal interactions between older and newer forms of modernity, the resurgence of older, presumably superseded, projects presents a kind of queer subversion of the temporal narratives of progress, modernity, and modernization. This subversion is instantiated in the present moment by the traditional Iberian horse (as the product and icon of an older, presumably superseded form of modernity). As a natureculture, this older modernity reverberates not only as a cultural investment but also as a “natural” resurgence of genetic diversity and multiplicity. This article theorizes the marginalized early modernities of Spain and Portugal in their baroque colonial multiplicities, and thereby rewrites the way European modernity has been understood.

Differences in Muscle Lipogenic Gene Expression, Carcass Traits and Fat Deposition among Three Iberian Pig Strains Finished in Two Different Feeding Systems.

The Iberian pig breed includes several well-differentiated strains. The present study evaluated carcass traits, fat deposition and muscle expression of important lipogenic genes (SCD, ME1, ACACA, FASN, EGR1, ACOX and ACLY) using 65 male pigs of 3 Iberian strains (20 Lampiño, 23 Torbiscal, and 22 Retinto) finished either in a conventional, concentrate-based system (CF) or in montanera (MF), a traditional free-range system with acorn feeding. Torbiscal had the highest ham, Longissimus thoracis and prime cuts yields, and the thinnest subcutaneous adipose tissue (SAT). Retinto had the highest monounsaturated fatty acids (MUFA) and percentage of intramuscular fat (IMF), while Lampiño had the greatest content of saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA), atherogenic (AI) and thrombogenic (TI) indexes in SAT. Conventionally finished pigs had the highest ham, L. thoracis and prime cuts yields, and SFA. Montanera-finished animals had the highest PUFA and MUFA contents, and the lowest AI, TI and n6/n3 ratio in SAT. In relation to gene expression, Retinto had the greatest SCD, FASN and ACLY levels. Most studied genes were overexpressed in CF pigs. In conclusion, MF pigs had healthier fat than CF pigs, and Retinto had the healthiest fat and the greatest lipogenic trend in muscle, supported by IMF and lipogenic gene expression.

Prediction of growth performance parameters in the growing and free-range finishing phases of the Iberian pig via meta-analysis

Aim of study: To describe and predict mathematically the growth parameters of Iberian pigs. Area of study: Iberian dehesa agroforestry system. Southwest of Iberian Peninsula. Material and methods: A quantitative and systematic review was carried out to find all studies with valid data of growth and finishing in the Iberian swine breed published up to May 2020. For the analysis of the data, a mathematical fitting model was obtained and a function was postulated to describe the relation between the variables age and body weight. Main results: 112 publications were found, and after applying several quality filters, 18 with age and weight matched data were used. The database was composed of 76 different tests and 22,558 animals. The clasical growth phases were independently evaluated for data analysis.It was necessary to separate the finishing trials into three groups according to the starting age. Seven mathematical models were obtained for lactation,post-weaning, and montanera finishing. However, no valid test data were found during the growth and prefinishing phases. Besides that, a single model was obtained combining lactation and post-weaning, and another surface model including the variables age and weight to compare average daily weight gain in montanera finishing phase. Research highlights: After systematic review of the studies that provide information on the growth of Iberian pigs, and a quantitative analysis, some mathematical linear and nonlinear models have been developed for the prediction of the production ratios at different phases.

Genetic relationships of the Yucatan black hairless pig with Iberian breeds using single nucleotide polymorfisms

To conduct ex-situ creole pig conservation programs, it is essential to determine which breeding animals will be used, preferentially those with a more significant Iberian genetic component to preserve their origin. This study used a Yucatan black hairless pigs (YBHP) subpopulation to estimate its genetic diversity and population structure. One hundred four adult pigs were selected for the absence of hair, black skin (without spots), black hoof, and straight snout. The porcine-GGP-50K chip was used for SNP genotyping in YBHP, and information on Iberian and Yucatán hairless pigs from the United States (USYU) was taken from databases. All analysis was performed using PLINK v1.9 and v2.1 software. Inbreeding and fixation index values were lower in YBHP, with high observed heterozygosity and allogamy index values, which agree with those obtained in the populations of Canarias and Chato Murciano. According to the clusters generated by the “Genome-Wide Identity by State” analysis, four groups were identified, one of which included pigs from Guadyerbas, USYU, and YBHP. Between populations, YBHP was closely related to the hairless pigs from Guadyerbas, USYU, and Canarias. Principal component analysis showed the same result. According to the results obtained from the runs of homozygosity investigation, aimed to get pools consensus of regions of overlapping, 119 SNPs associated with genes and biological processes were identified. The BMP7 and NSUN2 genes were associated with epithelial cell differentiation, morphogenesis, and epithelial development. For nutrient metabolism: energy, the HADHA, PPARA, ADD1/SREBF1, and FAT1genes were identified.

Second litter syndrome in Iberian pig breed: factors influencing the performance

Second litter syndrome (SLS) consists of a loss of prolificacy in the second parity (P2), when a sow presents the same or lower results for litter size than in the first parity (P1). This syndrome has been reported for modern prolific breeds but has not been studied for rustic breeds. The objectives of this study are to determine how and to what degree Iberian sows (a low productivity breed recently raised on intensive farms) are affected by SLS; to establish a target and reference levels; and to assess the factors influencing the performance. Analysed data correspond to 66 Spanish farms with a total of 126 140 Iberian sows. The average Iberian sow prolificacy in P1 was 8.91 total born (TB) and 8.47 born alive (BA) piglets, whereas in P2, it decreased by −0.05 TB and −0.01 BA piglets, suggesting some general incidence of SLS. At the sow level, 56.63% did not improve prolificacy in terms of BA piglets in P2, and 16.98% had a clear decrease in prolificacy, losing ≥3 BA piglets in P2. Within herds, a mean of 57.75% of sows showed SLS, with an evident decrease in the number of BA piglets in P2. The plausible target for the Iberian farm’s prolificacy comes from the quartile of farms with the lowest percentage of SLS sows within the farms with the highest prolificacy between P1 and P2 (mean of 8.77 BA). So, in this subset of farms (N = 17), 47.3% of sows improved their prolificacy in P2 (i.e. did not show SLS). Hence, half the sows could be expected to show SLS even on farms with a good performance. Finally, this study brings out the main factors reducing P2 prolificacy through SLS in the Iberian breed: later age at first farrowing, long first lactation length, medium weaning to conception interval and large litter size in P1. In conclusion, improving the reproductive performance of Iberian farms requires reducing the percentage of sows with SLS, paying special attention to those risk factors. The knowledge derived from this study can provide references for comparing and establishing objectives of performance on Iberian sow farms which can be used for other robust breeds.

Optimization of the Thawing Protocol for Iberian Boar Sperm.

Simple SummaryLimited attention is paid to sperm thawing protocols, and their study could be relevant to endangered species or breeds, especially for cryopreserved material present in the existing gene banks. The aim of this study was to determine the most optimal thawing protocol for Iberian boar sperm through testing different thawing rates and different modifications of the thawing extender. Based on the findings, the most optimal results were obtained thawing at 70 °C for 8 s with the inclusion of cyclodextrins loaded with cholesterol (CLC) in the extender, revealing the importance of adapting the thawing protocols.Thawing protocols have been barely studied, and their modifications may lead to a substantial improvement in post-thawing sperm quality, which could be of great relevance to existing sperm banks, such as those for Iberian pig breeds with varieties in danger of extinction. For that, the study aimed to evaluate different thawing rates and to evaluate modifications in the composition of the thawing extender (basic pH to 8–8.2, incorporation of cyclodextrins loaded with cholesterol [CLC] and the incorporation of ion chelators [EDTA and EGTA]). After thawing, overall sperm motility and kinematic parameters, acrosome status and sperm membrane integrity were evaluated. The most optimal results were obtained with the thawing rate reaching 70 °C for 8 s with the inclusion of 12.5 mg of CLC/500 × 106 spermatozoa in the thawing extender, which showed an improvement compared to the control at 70 °C. In conclusion, to adapt the thawing conditions may be relevant, especially for endangered species or breeds such as some varieties of Iberian pig, since this process could also be used in samples cryopreserved in gene banks.

Genetic origin of donkeys in Brazil.

The genetic groups of native donkeys in Brazil are characterized by adaptation to the local environment. However, the donkey population in the country is declining, mainly because of agricultural mechanization and transportation that has led to the abandonment and the consequent indiscriminate slaughter of these animals. There are three local genetic groups of distinct geographic and temporal formation. However, analyses of their origin, phylogenetic relationship, and population structure are scarce. Within this context, molecular markers such as the mitochondrial control region (D-loop) are useful for these analyses. This study aimed to evaluate the variation and origin of maternal lineages of groups of naturalized donkeys in Brazil (Brazilian, Nordestino, and Pêga). We detected five mitochondrial haplotypes with 19 polymorphic sites, two of them exclusively found in the Nordestino donkey; this group is in fact more distant from the others. Phylogenetic analysis indicates maternal contributions of two clades (Nubian and Somali) to the formation of the genetic groups of donkeys, a fact that explains the high diversity, structure, and distances of the groups, reported here for the first time. CONCLUSION: This analysis contributes production and conservation of native donkey breeds. It also gives clues about the formation of the Iberian breeds from which Brazilian donkeys originated.

A high-throughput DNA sequencing study of fecal bacteria of seven Mexican horse breeds.

Horses are non-ruminant, herbivorous mammals, been used through history for various purposes, with a gut microbiota from cecum to the colon, possessing remarkable fermentative capacity. We studied the fecal microbiota of Azteca, Criollo, Frisian, Iberian, Pinto, Quarter and Spanish horse breeds living in Mexico by next-generation DNA sequencing of 16S rRNA gene libraries. Dominant phyla Firmicutes, Bacteroidetes, Proteobacteria, Spirochaetes, Fibrobacteres, Actinobacteria and Verrucomicrobia have different relative abundances among breeds, with contrasted alpha and beta diversities as well. Heatmap analysis revealed that Ruminococcaceae, Lachnospiraceae, Mogibacteriaceae families, and order Clostridiales are more abundant in Spanish, Azteca, Quarter and Criollo breeds. The LEfSe analysis displayed higher abundance of order Bacteroidales, family BS11, and genera Faecalibacterium, Comamonas, Collinsella, Acetobacter, and Treponema in Criollo, Azteca, Iberian, Spanish, Frisian, Pinto, and Quarter horse breeds. The conclusion is that dominant bacterial taxa, found in fecal samples of horse breeds living in Mexico, have different relative abundances.

Genetic and productive background of Criollo cattle in Argentina, Mexico, Uruguay and the United States

Cattle were first introduced to the Western Hemisphere in 1493 and by subsequent introductions from the Iberian Peninsula, providing the genetic background of the American Criollo cattle, with influences from Spanish, Portuguese and African breeds. Criollo's high adaptive capacity enabled them to spread and colonize a wide variety of environments. Their ancestry combined with local adaptations created the wide spectrum of American Criollo breeds that we see today, many currently at risk of extinction. We review the existing genetic and production data on the Argentinian, Mexican, Uruguayan and US Creole cattle that form the basis of the current and future research described in this special issue. In these countries, Criollo cattle became the basis of the livestock industry for the supply of meat, hides and animal work, until they were displaced by more specialized European and cebuine type cattle breeds at the end of the 19th century. Since then, Criollo herds remained mostly in marginal regions unsuitable for commercial breeds. Efforts by local producers and research institutions helped to preserve Criollo populations. Several studies have demonstrated that these animals can produce high quality meat and are more resistant to diseases, and emphasize their high fertility, calving ease, longevity and ability to adapt to harsh environments. Mexican Criollos have high genetic diversity but lack strong conservation programs. More detailed genetic characterization within each regional Criollo population is needed to establish appropriate conservation strategies. In US, Texas Longhorn cattle are closely related to Mexican Criollos, while Pineywoods show a stronger relationship with Iberian breeds. Variable levels of genetic diversity were found among all North American Criollos, probably due to crossbreeding. Criollos from Argentina and Uruguay showed clear divergence due to genetic isolation but clustered together, representing the southernmost expansion of bovine cattle in the Americas.

Removal of undesirable MC1R gene alleles from ‘Berrenda en Negro’, an endangered Spanish cattle breed, to enhance breed conservation programs

‘Berrenda en Negro’ (BN) is an endangered Spanish cattle breed with substantial ecological and cultural value and meat quality. Phenotypically, it is differentiated by its black-sided coat pattern. The goal of this study were to analyse the presence of unwanted alleles at the MC1R locus (E+ and e) and propose appropriate selective strategies for their eradication from the population. Both goals were based on the identification of genotypes of the MC1R locus using genetic markers and DNA microsatellites, to identify changes in the genetic variability of the resulting populations after applying selective strategies to decrease the frequency of red and wild-type alleles. Introgression and crossbreeding of BN with other Iberian cattle breeds in the past has left undesirable E+ and e alleles, with frequencies of 7 and 12%, respectively. The extent to which the genetic variability of the BN population could be affected by selection strategies was quantified in terms of the number of affected animals and farms, effective population size (Ne) of the remaining genetic variability, and loss of gene diversity and allelic richness. The neutral genetic diversity found in BN suggested that selection strategies for the MC1R gene are possible. These strategies should be implemented progressively, in combination with extensive mating control. The best strategy to eliminate unwanted MC1R alleles in the short term would be to remove all cattle with the EDe genotype in the first phase, followed by a second phase, in which the EDE+ genotype would be eradicate after the recovery of the population to its effective size. The results of this study will assist the BN Breeders Association to managing the conservation program for the breed.

Changes in Biceps femoris Transcriptome along Growth in Iberian Pigs Fed Different Energy Sources and Comparative Analysis with Duroc Breed.

Simple SummaryThe genetic mechanisms that regulate biological processes, such as skeletal muscle development and growth, or intramuscular fat deposition, have attracted great interest, given their impact on production traits and meat quality. In this sense, a comparison of the transcriptome of skeletal muscle between phenotypically different pig breeds, or along growth, could be useful to improve the understanding of the molecular processes underlying the differences in muscle metabolism and phenotypic traits, potentially driving the identification of causal genes, regulators and metabolic pathways involved in their variability.This experiment was conducted to investigate the effects of developmental stage, breed, and diet energy source on the genome-wide expression, meat quality traits, and tissue composition of biceps femoris muscle in growing pure Iberian and Duroc pigs. The study comprised 59 Iberian (IB) and 19 Duroc (DU) animals, who started the treatment at an average live weight (LW) of 19.9 kg. The animals were kept under identical management conditions and fed two diets with different energy sources (6% high oleic sunflower oil or carbohydrates). Twenty-nine IB animals were slaughtered after seven days of treatment at an average LW of 24.1 kg, and 30 IB animals plus all the DU animals were slaughtered after 47 days at an average LW of 50.7 kg. The main factors affecting the muscle transcriptome were age, with 1832 differentially expressed genes (DEGs), and breed (1055 DEGs), while the effect of diet on the transcriptome was very small. The results indicated transcriptome changes along time in Iberian animals, being especially related to growth and tissue development, extracellular matrix (ECM) composition, and cytoskeleton organization, with DEGs affecting relevant functions and biological pathways, such as myogenesis. The breed also affected functions related to muscle development and cytoskeleton organization, as well as functions related to solute transport and lipid and carbohydrate metabolism. Taking into account the results of the two main comparisons (age and breed effects), we can postulate that the Iberian breed is more precocious than the Duroc breed, regarding myogenesis and muscle development, in the studied growing stage.

Morphological differentiation in a migratory bird across geographic gradients in mountains of southern Europe

AbstractAimIn temperate mountain ranges, sharp spatial variations in habitat heterogeneity and climate provide a perfect study setup to assess genetic and phenotypic differentiation in bird populations. In this paper, we analysed morphological divergence patterns across geographical and environmental gradients, in correlation with genetic differentiation and geographical isolation, in the breeding grounds of a long‐distance migratory passerine.LocationNorthwestern Iberian mountains.TaxonThe Iberian bluethroat, Luscina svecica azuricollis.MethodsWe collected a sample of 625 Iberian bluethroats across their whole breeding range to measure body weight and tarsus length, as well as wing length and pointedness. Morphological differentiation across geographical (latitude and elevation) and environmental (climate and vegetation) gradients was assessed using generalized linear mixed models. Additionally, the role of genetic distance and geographical isolation as drivers of morphological differentiation was evaluated with Mantel tests.ResultsBird morphology varied significantly with latitude and elevation, but not with climate or vegetation. In the case of latitude, morphological differences in body size were contrary to Bergmann's rule statements. All biometric and morphometric variables diverged among localities. A similar trend was found for genetic clusters, except for wing shape. Body weight and wing length were both correlated with geographic distance, while only the former varied with genetic differentiation. The greatest genetic and phenotypic differentiation was detected in the southernmost mountain range, that holds the most geographically isolated genetic group.Main conclusionEvidence suggests that the strong morphological differentiation observed in the Iberian breeding bluethroat across geographical gradients results from the combination of unambiguous deterministic forces, such as ecological selection mechanisms, and other factors, such as geographical isolation, that can be either deterministic, stochastic or both, all acting at different scales.

Performance and carcass quality traits of Iberian × Duroc crossbred pig subject to gender and age at the beginning of the free-range finishing phase

The traditional production of the Iberian breed pig involves a long production cycle. It might be shortened by using Iberian pigs crossed with Duroc and by reducing the growing phase, but the age-related changes on productive performance and carcass quality should be addressed. Thus, productive performance, live measurements and carcass and primal cut traits were evaluated on Iberian × Duroc 50:50 crossed pigs according to animal age at the beginning of the free-range finishing phase (Montanera): 10, 12 and 14 months old (IBxD10 (n = 15), IBxD12 (n = 17) and IBxD14 (n = 18) animal batches, respectively) and gender (immunologically castrated female -consisted of the Improvac® vaccination- and surgically castrated males). During the growing period, animals were fed with restrictions; 1.49, 1.29 and 1.20 ± 0.023 (mean ± SEM) kg/day of commercial feeds to start Montanera with similar BW; 103.9, 102.9 and 102.1 ± 0.22 kg, for IBxD10, IBxD12 and IBxD14, respectively. IBxD14 animals yielded the highest average daily gain (ADG) and BW after Montanera, as well as larger rump height and croup width. In contrast, these animals had the lowest carcass yield. Although animals from IBxD10 yielded hams of inferior size, this could be of interest to the sector, as there is a certain segment of the market that demands hams of smaller size and, generally, this is difficult to obtain with the traditional Montanera production system. The gender had no major effects on performance and carcass and primal cut traits, so both immunologically castrated female and surgically castrated males are suitable for finishing in Montanera.