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Maria Do Mar Oom - One of the best experts on this subject based on the ideXlab platform.

  • genetic diversity of the semi feral marismeno Horse Breed assessed with microsatellites
    Italian Journal of Animal Science, 2017
    Co-Authors: Montserrat Pablo Gomez, Cristina Luís, Maria Do Mar Oom, Vincenzo Landi, A M Martinez, Mayra Mercedes Gomez Carpio, Sergio Nogales Baena, Juan Vicente Delgado Bermejo, Lahoussine Ouragh, J L Vegapla
    Abstract:

    AbstractMarismeno Horses originated from primitive Horses living around the marshes of the Guadalquivir River in Southern Spain. Throughout their evolution, they have experienced crosses with other Breeds, first with Horses from North Africa and thereafter with other Horses. However, they have not lost their ability to adapt to the demanding marsh environment. Recently, a studbook of the Breed was established, and the Breeders Association started a conservation programme. To study the relationship of the Marismeno with other Breeds, a microsatellite analysis was developed, which included other ancient Southern Iberian Horse populations, such as the Sorraia and Retuertas Breeds. Candidates of recent crossBreeding with Marismeno Horses, such as the Hispano-Arabian and the Spanish Purebred, were studied, and the Thoroughbred and the Arabian Breed were used as international references. The results indicated that the Marismeno Horse population maintains a great genetic diversity. Despite recent crossBreeding, ...

  • impact of inBreeding on fitness related traits in the highly threatened sorraia Horse Breed
    Livestock Science, 2015
    Co-Authors: Helena J Kjollerstrom, L T Gama, Maria Do Mar Oom
    Abstract:

    Abstract The Sorraia Horse population can be regarded as a universal equine genetic resource, most likely the representative of the ancestor of Iberian saddle Horses and probably the ancestor of several New World Horse Breeds. The Breed was recovered in 1937 and managed without further additions to the initial founder group of 12 Horses, originating an extant population with extremely high inBreeding levels (mean F =0.38). There are only about 300 animals representing the Sorraia Horse population worldwide, which places it in a critical risk status and strongly supports the need to establish a conservation-Breeding plan aiming at a long-term self-sustaining population. Data on all registered Horses in the Sorraia Studbook were used to study the impact of inBreeding on offspring's viability at birth and at 6 months of age, and a sub-sample was used to determine the influence of inBreeding on stallion and mare fertility rates, foaling intervals and age at first parturition. The effect of inBreeding on the analysed traits was only significant for the relationship of mare fertility with mare inBreeding coefficient ( P =0.003). The influence of age of the mare was quadratic, with a reduction in foal mortality (both at birth and at six months of age) and an increase in foaling interval as age of mare increased. Stud farms had a statistically significant influence on age at first parturition. Decisive management-Breeding plans must be taken to control inBreeding levels in Sorraia Horses, and contribute to the conservation of this Breed.

  • genetic diversity and demographic structure of the endangered sorraia Horse Breed assessed through pedigree analysis
    Livestock Science, 2013
    Co-Authors: M Pinheiro, Helena J Kjollerstrom, Maria Do Mar Oom
    Abstract:

    Abstract The complete pedigree information included in the Sorraia Horse studbook was analyzed to investigate on the Breed's genetic variability and demographic structure and ascertain the status of the current population. The dataset included 653 animals registered since the Breed's foundation, in 1937, until 2006. In some cases, only a reference population consisting of 206 living animals was considered for the calculations. The inBreeding coefficients ( F ) and the genetic contribution of each founder to the population's genetic pool were assessed and parameters such as average relatedness (AR) and genetic importance of the studs were, for the first time, computed for this Breed. The average generation interval found for the whole pedigree was 7.94 yr. Consistent with previous results, low levels of genetic diversity were found for this Breed. The unbalanced use of animals for reproduction during most part of the Breed's history are reflected by the low values of effective number of founders (7.46) and effective number of ancestors (4) characterizing the whole population, with only 15 animals explaining its overall genetic variability. Extremely high values were reported for the F and AR coefficients and mean levels of 26.99% and 46.26% were observed. The rate of inBreeding per generation (5.2%) exceeds the 1% (0.01) maximum limit defined by FAO. Taking into account only the living population, roughly 97% of the animals showed F≥25% (some of them exhibiting values above 60%), and there were no cases with AR values lower than 50%. The average F, AR and mean kinship coefficients computed for this group were 36.90%, 55.11% and 0.34, respectively. Indicating high losses of genetic diversity through generations, great differences were found for the genetic contribution of each founder to the current genetic pool and some of these animals are no longer represented. In the more recent years, an improvement of the population's parameters can, although, be observed, especially as a consequence of the conservation strategies that are being carried out by the Breeders Association. The number of births registered in the studbook strongly increased in the last two decades and the average values of F and AR tended to stabilize and even decrease in the recent past. The results make clear that an efficient conservation plan is essential to insure the maintenance of this singular Breed. Appropriate management measures must continue to be implemented and improved as a way to preserve the genetic diversity still present in the population.

  • first evidence of sex chromosome mosaicism in the endangered sorraia Horse Breed
    Livestock Science, 2011
    Co-Authors: Helena J Kjollerstrom, M J Collarespereira, Maria Do Mar Oom
    Abstract:

    The Sorraia Horse is a critically endangered Portuguese Breed with an extremely reduced effective size, having reached unusual high levels of inBreeding. Fertility is of crucial importance for the long-term survival of the extant population and it has been shown that chromosomal abnormalities, especially on sex chromosomes, in Horses are associated with infertility or subfertility. To date, no cytogenetic studies were performed in the Sorraia Breed to assess the extent of chromosome abnormalities in animals with fertility problems. We now report the results of the first studied case — a subfertile mare with a stallion-like behaviour. A mosaic 63,X0/64,XX karyotype (with 10.45% and 89.55% frequency, respectively) was found. Further cytogenetic screenings in Sorraia Horses with low Breeding performance and ambiguous sexual phenotypes are needed, to determine the extent of chromosomal abnormalities, since early detection of these animals is of paramount importance for the management and conservation of the Breed.

  • InBreeding and Genetic Structure in the Endangered Sorraia Horse Breed: Implications for its Conservation and Management
    The Journal of heredity, 2007
    Co-Authors: Cristina Luís, E. Gus Cothran, Maria Do Mar Oom
    Abstract:

    The Sorraia Horse is a closed Breed with reduced effective population size and considered in critical maintained risk status. The Breed exists in 2 main Breeding populations, one in Portugal and one in Germany, with a smaller population size. A set of 22 microsatellite loci was used to examine genetic diversity and structure of the Sorraia Horse Breed and to compare individual inBreeding coefficient F, estimated from pedigree data, with individual heterozygosity and mean d 2 . The Sorraia Horse shows lower levels of microsatellite diversity when compared with other Horse Breeds. Due to management strategies, there are clear differences in the genetic structure of the 2 main Sorraia Horse populations. Individual heterozygosity was shown to be a good estimator, used together with or as an alternative to inBreeding coefficient, in predicting fitness and evaluating the inBreeding level of the Sorraia Horse. The information gathered in this study, combined with information available from previous studies, offers an important and wide information base for the future development of an effective Breeding management of the Sorraia Horse in order to preserve this endangered Breed.

Ernest Gus Cothran - One of the best experts on this subject based on the ideXlab platform.

  • Genetic Characterization of Cleveland Bay Horse Breed
    Diversity, 2019
    Co-Authors: Anas M Khanshour, Rytis Juras, Eleanore K. Hempsey, Ernest Gus Cothran
    Abstract:

    The Cleveland Bay (CB) is the United Kingdom’s oldest established Horse Breed. In this study we analyzed the genetic variability in CB Horses and investigated its genetic relationships with other Horse Breeds. We examined the genetic variability among 90 CB Horses sampled in the USA compared to a total of 3447 Horses from 59 other Breeds. Analysis of the genetic diversity and population structure was carried out using 15 microsatellite loci. We found that genetic diversity in CB Horses was less than that for the majority of other tested Breeds. The genetic similarity measures showed no direct relationship between the CB and Thoroughbred but suggested the Turkman Horses (likely in the lineage of ancestors of the Thoroughbred) as a possible ancestor. Our findings reveal the genetic uniqueness of the CB Breed and indicate its need to be preserved as a genetic resource.

  • Genetic diversity and population structure in remnant subpopulations of nordestino Horse Breed
    Archivos de Zootecnia, 2014
    Co-Authors: D. A. F. Pires, Ernest Gus Cothran, Rytis Juras, E. G. A. Coelho, J. B. Melo, Denise Aparecida Andrade De Oliveira, Maria Norma Ribeiro, Anas M Khanshour
    Abstract:

    This study analyzed four remnant subpopu- lations of Nordestino Horse Breed to detect genetic structure and diversity through 14 microsatellite markers. Hair root follicles from a total of 393 Horses were collected. There were 61 animals from Salitre Valley (JUAZ-BA) located at Bahia state, 89 from North and Central North ecoregions located at Piaui state (NCEN-PI), 185 animals from Sertao and Sertao do Sao Francisco ecoregions (SERT-PE) and 58 animals from Agrestina city (AGRE-PE) located at Pernambuco state. Genetic diversity, genetic differentiation and bottleneck effects were examined in the 4 remnant subpo- pulations of Nordestino Horse Breed. There was high allelic diversity and the F is value did not show evidence of a significant predominance of mating among relatives, probably because of crossbree- ding among populations. Recent bottleneck effects were not detected in the 4 subpopulations, but the IAM and TPM model did suggest a bottleneck effect. This may be a reflection of the decreased number of Breeding animals caused by castration of males, mechanization processes and changes in life style in the rural areas. The bottleneck event was not enough to lead a genetic differentiation among the 4 remnant subpopulations of Nordestino Horse. There was no evidence of genetic diffe- rentiation, so the 4 subpopulations formed one genetic group.

  • Maternal phylogenetic relationships and genetic variation among Arabian Horse populations using whole mitochondrial DNA D-loop sequencing
    BMC Genetics, 2013
    Co-Authors: Anas M Khanshour, Ernest Gus Cothran
    Abstract:

    Background Maternal inheritance is an essential point in Arabian Horse population genetics and strains classification. The mitochondrial DNA (mtDNA) sequencing is a highly informative tool to investigate maternal lineages. We sequenced the whole mtDNA D-loop of 251 Arabian Horses to study the genetic diversity and phylogenetic relationships of Arabian populations and to examine the traditional strain classification system that depends on maternal family lines using native Arabian Horses from the Middle East. Results The variability in the upstream region of the D-loop revealed additional differences among the haplotypes that had identical sequences in the hypervariable region 1 (HVR1). While the American-Arabians showed relatively low diversity, the Syrian population was the most variable and contained a very rare and old haplogroup. The Middle Eastern Horses had major genetic contributions to the Western Horses and there was no clear pattern of differentiation among all tested populations. Our results also showed that several individuals from different strains shared a single haplotype, and individuals from a single strain were represented in clearly separated haplogroups. Conclusions The whole mtDNA D-loop sequence was more powerful for analysis of the maternal genetic diversity in the Arabian Horses than using just the HVR1. Native populations from the Middle East, such as Syrians, could be suggested as a hot spot of genetic diversity and may help in understanding the evolution history of the Arabian Horse Breed. Most importantly, there was no evidence that the Arabian Horse Breed has clear subdivisions depending on the traditional maternal based strain classification system.

  • Maternal phylogenetic relationships and genetic variation among Arabian Horse populations using whole mitochondrial DNA D-loop sequencing
    BMC genetics, 2013
    Co-Authors: Anas M Khanshour, Ernest Gus Cothran
    Abstract:

    Maternal inheritance is an essential point in Arabian Horse population genetics and strains classification. The mitochondrial DNA (mtDNA) sequencing is a highly informative tool to investigate maternal lineages. We sequenced the whole mtDNA D-loop of 251 Arabian Horses to study the genetic diversity and phylogenetic relationships of Arabian populations and to examine the traditional strain classification system that depends on maternal family lines using native Arabian Horses from the Middle East. The variability in the upstream region of the D-loop revealed additional differences among the haplotypes that had identical sequences in the hypervariable region 1 (HVR1). While the American-Arabians showed relatively low diversity, the Syrian population was the most variable and contained a very rare and old haplogroup. The Middle Eastern Horses had major genetic contributions to the Western Horses and there was no clear pattern of differentiation among all tested populations. Our results also showed that several individuals from different strains shared a single haplotype, and individuals from a single strain were represented in clearly separated haplogroups. The whole mtDNA D-loop sequence was more powerful for analysis of the maternal genetic diversity in the Arabian Horses than using just the HVR1. Native populations from the Middle East, such as Syrians, could be suggested as a hot spot of genetic diversity and may help in understanding the evolution history of the Arabian Horse Breed. Most importantly, there was no evidence that the Arabian Horse Breed has clear subdivisions depending on the traditional maternal based strain classification system.

  • Microsatellite analysis for parentage testing of the Arabian Horse Breed from Syria
    TURKISH JOURNAL OF MEDICAL SCIENCES, 2013
    Co-Authors: Anas M Khanshour, Eleanore Conant, Rytis Juras, Ernest Gus Cothran
    Abstract:

    Parentage testing is very important for genetically determining the accuracy of the pedigree of domestic animals. The Arabian Horse population in Syria might be expected to have a high level of homozygosity because the traditional method of Breeding results in such a small population. For this reason, using a set of highly polymorphic markers such as microsatellites is required for parentage testing. The purpose of this study was to analyze the usefulness of 16 STR markers for routine parentage testing in 94 samples from registered and nonregistered Horses collected from Syria. The mean number of alleles was 5.69 per locus in the registered group and 7.69 in the nonregistered group. The nonregistered group had a mean polymorphic information content (PIC) of 0.715, which was significantly higher than the PIC in the registered group. The individual probability of exclusion per locus ranged from 32% for HTG7 to 80% for ASB17 in the registered group and 41% for HTG7 to 84% for ASB17 in the nonregistered group. The results of this study indicate no serious loss of heterozygosity and confirm that 13 STR markers can be used in parentage testing with high efficiency for the Arabian Horses from Syria.

Anas M Khanshour - One of the best experts on this subject based on the ideXlab platform.

  • Genetic Characterization of Cleveland Bay Horse Breed
    Diversity, 2019
    Co-Authors: Anas M Khanshour, Rytis Juras, Eleanore K. Hempsey, Ernest Gus Cothran
    Abstract:

    The Cleveland Bay (CB) is the United Kingdom’s oldest established Horse Breed. In this study we analyzed the genetic variability in CB Horses and investigated its genetic relationships with other Horse Breeds. We examined the genetic variability among 90 CB Horses sampled in the USA compared to a total of 3447 Horses from 59 other Breeds. Analysis of the genetic diversity and population structure was carried out using 15 microsatellite loci. We found that genetic diversity in CB Horses was less than that for the majority of other tested Breeds. The genetic similarity measures showed no direct relationship between the CB and Thoroughbred but suggested the Turkman Horses (likely in the lineage of ancestors of the Thoroughbred) as a possible ancestor. Our findings reveal the genetic uniqueness of the CB Breed and indicate its need to be preserved as a genetic resource.

  • Genetic diversity and population structure in remnant subpopulations of nordestino Horse Breed
    Archivos de Zootecnia, 2014
    Co-Authors: D. A. F. Pires, Ernest Gus Cothran, Rytis Juras, E. G. A. Coelho, J. B. Melo, Denise Aparecida Andrade De Oliveira, Maria Norma Ribeiro, Anas M Khanshour
    Abstract:

    This study analyzed four remnant subpopu- lations of Nordestino Horse Breed to detect genetic structure and diversity through 14 microsatellite markers. Hair root follicles from a total of 393 Horses were collected. There were 61 animals from Salitre Valley (JUAZ-BA) located at Bahia state, 89 from North and Central North ecoregions located at Piaui state (NCEN-PI), 185 animals from Sertao and Sertao do Sao Francisco ecoregions (SERT-PE) and 58 animals from Agrestina city (AGRE-PE) located at Pernambuco state. Genetic diversity, genetic differentiation and bottleneck effects were examined in the 4 remnant subpo- pulations of Nordestino Horse Breed. There was high allelic diversity and the F is value did not show evidence of a significant predominance of mating among relatives, probably because of crossbree- ding among populations. Recent bottleneck effects were not detected in the 4 subpopulations, but the IAM and TPM model did suggest a bottleneck effect. This may be a reflection of the decreased number of Breeding animals caused by castration of males, mechanization processes and changes in life style in the rural areas. The bottleneck event was not enough to lead a genetic differentiation among the 4 remnant subpopulations of Nordestino Horse. There was no evidence of genetic diffe- rentiation, so the 4 subpopulations formed one genetic group.

  • Maternal phylogenetic relationships and genetic variation among Arabian Horse populations using whole mitochondrial DNA D-loop sequencing
    BMC Genetics, 2013
    Co-Authors: Anas M Khanshour, Ernest Gus Cothran
    Abstract:

    Background Maternal inheritance is an essential point in Arabian Horse population genetics and strains classification. The mitochondrial DNA (mtDNA) sequencing is a highly informative tool to investigate maternal lineages. We sequenced the whole mtDNA D-loop of 251 Arabian Horses to study the genetic diversity and phylogenetic relationships of Arabian populations and to examine the traditional strain classification system that depends on maternal family lines using native Arabian Horses from the Middle East. Results The variability in the upstream region of the D-loop revealed additional differences among the haplotypes that had identical sequences in the hypervariable region 1 (HVR1). While the American-Arabians showed relatively low diversity, the Syrian population was the most variable and contained a very rare and old haplogroup. The Middle Eastern Horses had major genetic contributions to the Western Horses and there was no clear pattern of differentiation among all tested populations. Our results also showed that several individuals from different strains shared a single haplotype, and individuals from a single strain were represented in clearly separated haplogroups. Conclusions The whole mtDNA D-loop sequence was more powerful for analysis of the maternal genetic diversity in the Arabian Horses than using just the HVR1. Native populations from the Middle East, such as Syrians, could be suggested as a hot spot of genetic diversity and may help in understanding the evolution history of the Arabian Horse Breed. Most importantly, there was no evidence that the Arabian Horse Breed has clear subdivisions depending on the traditional maternal based strain classification system.

  • Maternal phylogenetic relationships and genetic variation among Arabian Horse populations using whole mitochondrial DNA D-loop sequencing
    BMC genetics, 2013
    Co-Authors: Anas M Khanshour, Ernest Gus Cothran
    Abstract:

    Maternal inheritance is an essential point in Arabian Horse population genetics and strains classification. The mitochondrial DNA (mtDNA) sequencing is a highly informative tool to investigate maternal lineages. We sequenced the whole mtDNA D-loop of 251 Arabian Horses to study the genetic diversity and phylogenetic relationships of Arabian populations and to examine the traditional strain classification system that depends on maternal family lines using native Arabian Horses from the Middle East. The variability in the upstream region of the D-loop revealed additional differences among the haplotypes that had identical sequences in the hypervariable region 1 (HVR1). While the American-Arabians showed relatively low diversity, the Syrian population was the most variable and contained a very rare and old haplogroup. The Middle Eastern Horses had major genetic contributions to the Western Horses and there was no clear pattern of differentiation among all tested populations. Our results also showed that several individuals from different strains shared a single haplotype, and individuals from a single strain were represented in clearly separated haplogroups. The whole mtDNA D-loop sequence was more powerful for analysis of the maternal genetic diversity in the Arabian Horses than using just the HVR1. Native populations from the Middle East, such as Syrians, could be suggested as a hot spot of genetic diversity and may help in understanding the evolution history of the Arabian Horse Breed. Most importantly, there was no evidence that the Arabian Horse Breed has clear subdivisions depending on the traditional maternal based strain classification system.

  • Microsatellite analysis for parentage testing of the Arabian Horse Breed from Syria
    TURKISH JOURNAL OF MEDICAL SCIENCES, 2013
    Co-Authors: Anas M Khanshour, Eleanore Conant, Rytis Juras, Ernest Gus Cothran
    Abstract:

    Parentage testing is very important for genetically determining the accuracy of the pedigree of domestic animals. The Arabian Horse population in Syria might be expected to have a high level of homozygosity because the traditional method of Breeding results in such a small population. For this reason, using a set of highly polymorphic markers such as microsatellites is required for parentage testing. The purpose of this study was to analyze the usefulness of 16 STR markers for routine parentage testing in 94 samples from registered and nonregistered Horses collected from Syria. The mean number of alleles was 5.69 per locus in the registered group and 7.69 in the nonregistered group. The nonregistered group had a mean polymorphic information content (PIC) of 0.715, which was significantly higher than the PIC in the registered group. The individual probability of exclusion per locus ranged from 32% for HTG7 to 80% for ASB17 in the registered group and 41% for HTG7 to 84% for ASB17 in the nonregistered group. The results of this study indicate no serious loss of heterozygosity and confirm that 13 STR markers can be used in parentage testing with high efficiency for the Arabian Horses from Syria.

Lea Brinkmann - One of the best experts on this subject based on the ideXlab platform.

  • Effect of long-term feed restriction on the health status and welfare of a robust Horse Breed, the Shetland pony (Equus ferus caballus).
    Research in Veterinary Science, 2013
    Co-Authors: Lea Brinkmann
    Abstract:

    Outdoor group housing is increasingly recognized as an appropriate housing system for domesticated Horses. The objective of this study was therefore to investigate the effect of potential feed shortage in semi-natural Horse keeping systems in winter on animal health and welfare. In 10 female Shetland ponies blood concentrations (NEFA, total protein (TP), total bilirubin (TB), beta-hydroxybutyrate (BHB) and thyroxine (T4)), body mass and the body condition score (BCS) were monitored for 7 months including a 4 months period of feed restriction in five of the 10 ponies. Restrictively fed animals lost 18.4 ± 2.99% of their body mass and the BCS decreased by 2.2 ± 0.8 points (BCS scale: 0 = emaciated, 5 = obese). Feed restriction led to a continuous increase in TB (P < 0.001) and NEFA (P < 0.01) concentrations compared to control ponies. The TP and BHB values only differed at the end of the trial with lower concentrations in restricted fed mares (P < 0.05). Feed restriction had no effect on thyroxine concentrations. TB concentrations in the feed restricted group were out of the reference range during the entire feeding trial. The increased NEFA concentrations in feed restricted compared to control ponies suggest that fat was mobilized. The BCS, as well as plasma NEFA and TB concentrations were good indicators for a rapid detection of possible health problems caused by undernourishment in Horses when kept under semi-natural conditions. In contrast, blood parameters of the control animals were within the reference ranges, suggesting that a year round outdoor housing with additional feed supply is an adequate housing system for a robust Horse Breed like the Shetland pony.

  • adaptation strategies to seasonal changes in environmental conditions of a domesticated Horse Breed the shetland pony equus ferus caballus
    The Journal of Experimental Biology, 2012
    Co-Authors: Lea Brinkmann
    Abstract:

    Recent results suggest that the wild ancestor of the Horse, the Przewalski Horse, exhibits signs of a hypometabolism. However, there are speculations that domestic animals lost the ability to reduce energy expenditure during food shortage and adverse environmental conditions. Therefore, we investigated physiological and behavioural strategies employed by a robust domesticated Horse Breed, the Shetland pony, over the course of a year under temperate conditions by measuring ambient temperature ( T a), subcutaneous temperature ( T s), locomotor activity (LA), lying time, resting heart rate, body mass and body condition score. Ten animals were kept on pasture in summer and in open stables in winter; further, in winter the animals were allocated into one control and one feed-restricted group of five animals each to simulate natural seasonal food shortage. The annual course of the mean daily T s of all Horses showed distinct fluctuations from a mean of 35.6±0.5°C, with higher variations in summer than in winter. Diurnal amplitudes in T s were highest ( P <0.001) in April (12.6°C) and lowest in January (4.0°C), with a nadir around dawn and a peak around mid-day. The feed-restricted group had a significantly lower daily T s compared with the control group on cold winter days, with T a values below 0°C. Mean annual heart rate and LA followed T a closely. Heart rate of the feed-restricted animals significantly decreased from a mean of 52.8±8.1 beats min–1 in summer to 29±3.9 beats min–1 in winter and differed from the control group ( P <0.001). Mean daily LA was lowest at the end of winter (7000 activity impulses day–1) and highest in summer (25,000 activity impulses day–1). Our results show that Shetland ponies exhibit signs of a winter hypometabolism indicated by reduced heart rate and T s. Thus, domesticated Horses seem to have maintained the capacity for seasonal adaptation to environmental conditions by seasonal fluctuations in their metabolic rate.

  • Adaptation strategies to seasonal changes in environmental conditions of a domesticated Horse Breed, the Shetland pony ( Equus ferus caballus )
    Journal of Experimental Biology, 2012
    Co-Authors: Lea Brinkmann
    Abstract:

    Recent results suggest that the wild ancestor of the Horse, the Przewalski Horse, exhibits signs of a hypometabolism. However, there are speculations that domestic animals lost the ability to reduce energy expenditure during food shortage and adverse environmental conditions. Therefore, we investigated physiological and behavioural strategies employed by a robust domesticated Horse Breed, the Shetland pony, over the course of a year under temperate conditions by measuring ambient temperature ( T a), subcutaneous temperature ( T s), locomotor activity (LA), lying time, resting heart rate, body mass and body condition score. Ten animals were kept on pasture in summer and in open stables in winter; further, in winter the animals were allocated into one control and one feed-restricted group of five animals each to simulate natural seasonal food shortage. The annual course of the mean daily T s of all Horses showed distinct fluctuations from a mean of 35.6±0.5°C, with higher variations in summer than in winter. Diurnal amplitudes in T s were highest ( P

Cristina Luís - One of the best experts on this subject based on the ideXlab platform.

  • genetic diversity of the semi feral marismeno Horse Breed assessed with microsatellites
    Italian Journal of Animal Science, 2017
    Co-Authors: Montserrat Pablo Gomez, Cristina Luís, Maria Do Mar Oom, Vincenzo Landi, A M Martinez, Mayra Mercedes Gomez Carpio, Sergio Nogales Baena, Juan Vicente Delgado Bermejo, Lahoussine Ouragh, J L Vegapla
    Abstract:

    AbstractMarismeno Horses originated from primitive Horses living around the marshes of the Guadalquivir River in Southern Spain. Throughout their evolution, they have experienced crosses with other Breeds, first with Horses from North Africa and thereafter with other Horses. However, they have not lost their ability to adapt to the demanding marsh environment. Recently, a studbook of the Breed was established, and the Breeders Association started a conservation programme. To study the relationship of the Marismeno with other Breeds, a microsatellite analysis was developed, which included other ancient Southern Iberian Horse populations, such as the Sorraia and Retuertas Breeds. Candidates of recent crossBreeding with Marismeno Horses, such as the Hispano-Arabian and the Spanish Purebred, were studied, and the Thoroughbred and the Arabian Breed were used as international references. The results indicated that the Marismeno Horse population maintains a great genetic diversity. Despite recent crossBreeding, ...

  • InBreeding and Genetic Structure in the Endangered Sorraia Horse Breed: Implications for its Conservation and Management
    The Journal of heredity, 2007
    Co-Authors: Cristina Luís, E. Gus Cothran, Maria Do Mar Oom
    Abstract:

    The Sorraia Horse is a closed Breed with reduced effective population size and considered in critical maintained risk status. The Breed exists in 2 main Breeding populations, one in Portugal and one in Germany, with a smaller population size. A set of 22 microsatellite loci was used to examine genetic diversity and structure of the Sorraia Horse Breed and to compare individual inBreeding coefficient F, estimated from pedigree data, with individual heterozygosity and mean d 2 . The Sorraia Horse shows lower levels of microsatellite diversity when compared with other Horse Breeds. Due to management strategies, there are clear differences in the genetic structure of the 2 main Sorraia Horse populations. Individual heterozygosity was shown to be a good estimator, used together with or as an alternative to inBreeding coefficient, in predicting fitness and evaluating the inBreeding level of the Sorraia Horse. The information gathered in this study, combined with information available from previous studies, offers an important and wide information base for the future development of an effective Breeding management of the Sorraia Horse in order to preserve this endangered Breed.

  • A lost Sorraia maternal lineage found in the Lusitano Horse Breed.
    Journal of animal breeding and genetics = Zeitschrift fur Tierzuchtung und Zuchtungsbiologie, 2006
    Co-Authors: Cristina Luís, Cristiane Bastos-silveira, J. Costa-ferreira, E. G. Cothran, Maria Do Mar Oom
    Abstract:

    A common female founder individual of the Portuguese Horse Breeds Sorraia and Lusitano was found while conducting research on the variation of the Lusitano mitochondrial DNA lineages in relation to studbook information. We obtained 416-bp control region sequences from 16 descendents of a female Sorraia founder (Pomba) still represented in the living population of the Lusitano, according to the most recent edition of this Breed's studbook. The same haplotype was found for all analysed samples and belongs to the haplogroup described by several authors as having predominantly Iberian, South American and North African haplotypes bringing new insights on the relationship between the Sorraia and the other Iberian Breeds. This work illustrates how weak the boundary of Breed establishment can be, especially at the same geographical region. Using the same founders in different Breeds is surely one of the explanations to frequently shared haplotypes among recent Breeds, resulting in a lack of consistency between mtDNA sequences and Breeds and/or geographical regions.

  • variation in the mitochondrial control region sequence between the two maternal lines of the sorraia Horse Breed
    Genetics and Molecular Biology, 2002
    Co-Authors: Cristina Luís, Cristiane Bastossilveira, Gus E Cothran, Maria Do Mar Oom
    Abstract:

    The mitochondrial control region sequence was compared between the two surviving matrilineal lineages of the Sorraia Horse. Two haplotypes were found, showing three differences between them. The reduced number of surviving maternal lineages emphasizes the importance of establishing a conservation plan for this endangered Breed.