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1.
Polish Arabian horses are a good example of a small population derived from a finite number of founders. Pedigree analysis showed significant reduction in the genetic diversity of the population. However, taking into account some circumstances suggesting the presence of balancing selection favouring heterozygotes in Polish breeding, it seems that this referred to pedigree uniformity rather than to a real decrease in genetic variability. The aim of the current study was to verify the hypothesis that balancing selection affects the population. The mare selection process was examined in detail regarding the polymorphism of 10 protein markers. The findings confirmed the tendency to favour the more heterozygous mares with regard to average heterozygosity in total and in relation to particular loci, studs, fathers and inbreeding ranges. The results were discussed in consideration of selection criteria, inbreeding level of Polish Arabs and heterozygosity in other populations. 相似文献
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R. Kasarda L. Vostrý N. Moravčíková H. Vostrá-Vydrová P. Dovč O. Kadlečík 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2016,66(2):67-74
The aim of the present study was to analyse the genetic subdivision of the Old Kladruber horse population compared to the historically close Lipizzan breed and to estimate genetic relatedness between them. A set of 13 microsatellites was used for genotyping a total of 270 Old Kladruber horses representing grey and black colour varieties and 418 Lipizzan horses from Slovak and Slovenian studs. The proportion of obtained heterozygosity indicates no major loss of genetic diversity within them. At the individual level across analysed populations, the formation of clusters in respect to breed’s origin and particular studs was observed. The Wright’s FST and genetic distances indicated genetic segregation of both colour varieties at the intraspecific level of the Kladruber breed. Moreover, the membership probability outputs showed that the frequencies of alleles varied across the three main regions represented by both Old Kladruber varieties and Lipizzan, depending on breeding history and strategy of studs. 相似文献
3.
A data set constituting a total of 310,109 Hanoverian warmblood horses was analyzed to ascertain the genetic variability, coefficients of inbreeding, and gene contributions of foreign populations. The reference population contained all Hanoverian horses born from 1980 to 2000. In addition, Hanoverian stallions born from 1980 to 1995 and Hanoverian breeding mares from the birth years 1980 to 1995 with registered foals were analyzed for the same genetic parameters. The average complete generation equivalent was approximately 8.43 for the reference population. The mean coefficient of inbreeding was 1.33, 1.19, and 1.29% for the reference population, stallions, and breeding mares, respectively. The effective number of founders was largest in stallions (364.3) and smallest in the reference population (244.9). The ratio between the effective number of founders and the effective number of ancestors was 3.15 for the reference population, 3.25 for the stallions, and 3.06 for the breeding mares. The effective population size in the Hanoverian warmblood reference population was 372.34. English Thoroughbreds contributed nearly 35% of the genes to the Hanoverian reference population and even slightly greater contributions (39%) to the stallions. Trakehner and Arab horses contributed approximately 8 and 2.7%, respectively, to the Hanoverian gene pool. The most important male ancestors were Aldermann I from the A/E line, Fling from the F/W line, and Absatz from the Trakehner line, whereas the breeding mare Costane had the greatest contribution to the reference population, stallions, and breeding mares. From 1996 onward, the stallions Weltmeyer and Donnerhall had the largest genetic impact on the Hanoverian horse population. 相似文献
4.
Genetic Diversity and Population Structure of Arabian Horse Populations Using Microsatellite Markers
Understanding the genetic diversity and the relationships among the show Arabian horse populations is a current issue for breeders and professionals. This study aimed to define the relationship among the Desert breed, the Straight Egyptian, and the Polish Arabian populations by considering the historical background of their origin and to verify their genetic diversity. All selected samples were related to Arabian show activities. One hundred forty four hair samples were collected from horses at stud farms having notoriety in the breeding of Arabians from different geographic regions. A set of 17 microsatellites markers for parentage control were used for genotyping. Genetic diversity among and between these populations were evaluated using several statistical methods. All the microsatellites were informative and the marker set analyzed provided 145 alleles. The average number of alleles per locus was 6.52, 6.35, and 7 for the Desert breed, Straight Egyptian, and Polish Arabian, respectively. The high genetic diversity observed within the three populations (0.63-0.71) was associated with a high number of effective alleles. Desert breed and Polish Arabian populations appeared the closest, whereas the Egyptian population was more distant. The significant positive inbreeding coefficient FIS found in Desert breed, Straight Egyptian, and Polish Arabian horses (0.09, 0.14, and 0.11, respectively) confirmed the deficit of heterozygosity observed in these populations. These results suggested that the three populations have high levels of gene flow or share the same origin and have a recent divergence. This study may highlight the risk of the loss of gene diversity in these populations and help to implement appropriate breeding programs to preserve genetic diversity. 相似文献
5.
Peter W. Physick-Sheard 《Preventive veterinary medicine》1995,24(4):285-299
This study derives demographic parameters for the Canadian Standardbred broodmare herd by analysis of industry mating reports for the years 1986–1989 inclusive. The reference population for the study was all mares bred to Canadian-registered stallions. Number of matings evaluated ranged from 9169 to 9837 in each year. In establishing the size of the national herd, data from registration files for 1986 also were used to estimate the number of Canadian mares bred to US stallions. The national broodmare herd was estimated to consist of 12 237 mares, of which 7.7% annually were bred to US-registered stallions. An estimated 16.7% of the national herd were inactive (not presented for breeding) in any year. Probability of temporary absence from the breeding herd was influenced by age, decreasing from 2 to 6 years, then increasing thereafter. Age-specific culling rates revealed that mares less than 6 years of age were subject to more intense selection pressure than was evident for mares more than 10 years of age. Inconsistent presentation for breeding appeared to be a feature of the management of young broodmares. Overall herd culling rate was estimated to be 10.5%, equivalent to an average breeding life of 9.5 years. It was determined that the average broodmare breeds for 7.9, or 83%, of available years. The results clearly indicate that the reproductive advantage enjoyed by mares 6 years of age results, in part, from more consistent presentation for breeding. 相似文献
6.
le Jeune SS Nieto JE Dechant JE Snyder JR 《Veterinary journal (London, England : 1997)》2009,181(3):251-255
Gastroscopic examinations were performed in 62 Thoroughbred broodmares (33 pregnant, 29 non-pregnant) at one breeding farm to investigate the prevalence of gastric ulceration. Age, pregnancy status, race earnings, last race start, herd size, medical history, number of live foals, breeding years, feed type and number of feedings were recorded, plus coat condition and body condition score were determined. Twenty-one mares were re-evaluated after foaling, and the foaling date, foal weight at birth and placenta weight were recorded.The overall prevalence of gastric ulcers was 70.9%, with a median ulcer score of 3.0 (range: 2–5). Most ulcers were present on the squamous portion of the stomach, while two mares had glandular ulcers. There were no differences in the presence, location and severity of gastric ulcers between pregnant and non-pregnant mares. Furthermore, there were no significant associations between the variables measured and the presence of gastric ulceration. The prevalence of gastric ulceration in this specific population of horses was higher than expected and further investigation is warranted to determine the factors that contributed to this finding. 相似文献
7.
旨在揭示康西草原马匹的品种来源以及群体遗传结构。本研究采集了当地60匹健康状况良好、体重适中、3～6岁之间不区分公母马的血液样品,试验分为6个种群并以纯血马等4个国外马品种、1个我国地方马品种作为对照， 通过设计引物并提取基因组DNA结合微卫星扩增法对染色体上12个微卫星位点的等位基因进行检测，并对各种群遗传多样性参数、群体分化指数、瓶颈效应以及群体结构进行分析。试验按照群体个数为依据分为6组，每组1个重复，每个重复以该组样本量为标准。分析6个种群马的遗传参数结果表明，其中共检测到221个等位基因,平均Shannon指数为1.691；有效等位基因数(Ne)为3.649～5.397；期望杂合度(He)为0.681～0.798；观测杂合度(Ho)为0.632～0.780；平均多态信息含量(PIC)为0.643～0.772。这些结果表明，6个群体都具有很高的遗传多样性。通过微卫星DNA位点的连锁不平衡及哈迪-温伯格平衡分析发现， 大多数位点的P值都大于校正值(P=0.006 5)，表示较多位点都处于哈迪-温伯格及连锁平衡状态。各群体间群体分化系数(Fst)表明，群体间分化程度较低(Fst<0.15)。基于Nei’s遗传距离与地理距离之间Mantel相关性检验显示二者之间呈现正相关性(R=0.502)，但未达到显著水平(P=0.310)；各马匹种群瓶颈效应分析表明，P值极显著(P(IAM)<0.01)说明该地区的马群体受到过瓶颈效应的影响且该马群体历史上数量有大规模的减少。通过 FCA因子分析、基于Nei’s标准遗传距离UPGMA树状图以及Structure贝叶斯聚类分析发现，该地区马种群与纯血马和温血马聚为一类，说明该种群最有可能主要来源于温血马和纯血马。这些结果揭示，康西草原地区马匹具有较高的遗传多样性，该地马群体的血统与纯血马和温血马相近，这为当地马遗传资源评估以及开发利用打下了坚实的基础。 相似文献
8.
Inbreeding and heterozygosity levels were calculated in a population of 77 horses of the endangered Skyros breed that had been raised since 1988 at an experimental farm. Twenty one horses were inbred with average inbreeding coefficient of 0.11 ( ± 0.02). Annual inbreeding change over the last 10 years was not significant (P > 0.05). Animals were genotyped for 18 microsatellite markers. Average number of alleles was 4.11 ( ± 0.43). Average theoretical and observed heterozygosity were 0.63 ( ± 0.06) and 0.66 ( ± 0.06), respectively. The probability of paternity exclusion with 1 and 2 parents unconfirmed was 0.9890 and 0.9999, respectively. Genetic diversity levels were reasonable and comparable to results from other breeds internationally. 相似文献
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Donkeys are bred throughout the world and often play an important role in agriculture. They are also bred to produce mules. Traditionally, jacks are considered challenging to breed in domestic conditions, whether for natural breeding or semen collection using either jennies or mares. The donkey's natural sexual behaviour significantly differs from that of other domestic animals. This presents challenges for in‐hand donkey breeding, particularly on mule studs where normally only jacks and mares are kept for breeding. This article describes some of the authors' observations on sexual behaviour in donkeys and practical experience of some of the strategies employed to apply this knowledge to breeding management, in order to improve the success of using donkeys for both natural service and semen collection. 相似文献
12.
The objective of the study has been to verify the hypothesis that the coat colour is regarded in the selection of Polish Thoroughbred horse population. Formally, the colour is not a selection criterion in this breed selected mainly for speed. The material consisted of twelve groups of foals registered in successive volumes of the Stud Book (11,688 foals, in total) and their parents selected to the breeding stud. The frequency of alleles in ASIP, MC1R and GREY loci controlling the coat colours was estimated from the recessive phenotype frequency square in the groups of foals. The inflow of foreign genes was limited and the population great, hence the migration effect was very low. The drift and Wahlund effect hardly influenced the genetic structure in the groups which enabled to analyze the population not divided. The total offspring frequency of recessive a, e and g alleles amounted to 0.1552, 0.4877 and 0.9773, respectively. Accuracy of the assessment of the a and e frequency was confirmed on the basis of test matings. The a, e and g alleles were more frequent in dams than in sires and the a alleles occurred more often in fillies than in colts. The frequency of a and e alleles was higher in the offspring than in the parents. The genotype distribution in the offspring differed from the expected one, assessed from the gamete frequency in sires and in dams. Fewer bay foals were born than anticipated. All the results show that the coat colour is not entirely disregarded in the breeding of Thoroughbred horses. The dominant A and E alleles producing the colour are preferred in the selection, particularly in the sires. This leads to some alterations in the phenotypic structure of the population. On the other hand, the horses are mated randomly, irrespective of the coat colour. 相似文献
13.
The length of gestation in Carthusian broodmares was calculated on the basis of 339 spontaneous full-term deliveries taking place in the 8-year period 1998-2005 from 158 broodmares and 29 stallions in a major farm of Spanish horses of Carthusian strain in southern Spain. Ultrasonography was used to determine follicular dehiscence, 1st day of pregnancy and to confirm conception in mares. Mean GL was 332.4 +/- 12.1 days, and a normal interval of 297-358 days was established for this breed. GL records were grouped on the basis of foal sex (colts or fillies), mating month (between November and January; February and April; May and July), age of the mare (4 to 7 years; 8 to 12 years; 13 to 17 years), breeding year, stallion and parity (primiparous vs. multiparous). GLs were 12.9 days shorter in mares mated between May and July than those mated between November and January and 15.3 days in mares mated between February and April (p < 0.001). Mares aged between 8-12 years had 5.3 days shorter GLs than those aged between 13-17 years (p < 0.05). Pregnancy was significantly 5.7 days longer when the mare gave birth to colts than fillies (p < 0.05). GL was 14.5 days longer in primiparous than in multiparous mares ( p < 0.001). No statistical differences in GL were found between the studied years. This study shows the influence of certain stallion on GL. 相似文献
14.
LR JORM 《Australian veterinary journal》1990,67(12):436-439
A questionnaire survey of 179 horse studs in New South Wales was conducted to estimate the incidence of strangles during 1985 to 1988, to identify risk factors for strangles outbreaks and to assess the effect of strangles vaccination. Forty-nine of the studs (27.4%) had at least one strangles outbreak during this period and 62 studs (34.6%) had at least one case of strangles. The average incidence of strangles was 2.1 cases per 100 horses per year. The risk of strangles increased progressively with the total horse population and rose markedly when more than 100 mares had been served in the 1988-89 season. Certain types of feeders, fences and water sources were also significantly associated with outbreaks of strangles. Strangles vaccine was used on 63 studs (35.2%). Thirty-seven of these (58.7%) used the manufacturer's recommended vaccination regime. When other risk factors were taken into account, vaccination had no significant effect on the likelihood of a strangles outbreak. 相似文献
15.
The aim of the study was to determine the situation of equine arteritis virus (EAV) infections in hucul horses. A total of 176 horses (154 mares and 22 stallions) from the biggest hucul horse stud in Poland were tested. Antibodies against EAV were detected in 97 (55.1%) horses. The EAV seroprevalence among mares was 53.2% while in stallions - 68.2%. The percentage of positive mares increased with their age, thus amongst the mares of less than 2 years of age the percentage was 32.5%, while in the group of 3-5 years old increased to 59.4% and in the mares in the age of 6-10 years and older than 10 years 89.5% and 95% were seropositive, respectively. Among 11 seropositive stallions five were supposed to be shedders of EAV with their semen. It is likely that those persistently infected stallions were the reservoirs of the virus in the stud. Genetic studies using of ORF5 gene showed high homology between the viruses detected in the semen of those stallions what suggested lateral transmission between the stallions sharing the same stable. Persistent infection in an immature stallion, which has not yet been used for breeding, was established as a result of infection via respiratory route. Phylogenetic analysis confirmed that all hucul viruses shared the same ancestor and as most of EAV strains dominating in Polish horse population belonged to the European origin EAV subgroup (EU-1). 相似文献
16.
Vest DJ Cohen ND Berezowski CJ Morehead JP Blodgett GP Blanchard TL 《Journal of the American Veterinary Medical Association》2004,225(12):1894-1897
OBJECTIVE: To determine whether administration of killed West Nile virus vaccine was associated with pregnancy loss among broodmares. DESIGN: Retrospective cohort study. ANIMALS: 595 mares. PROCEDURE: Records of pregnant mares with known vaccination history from 4 farms were reviewed. Information obtained from 595 mares included mare's identification; farm; age; breed; reproductive status; last breeding date; date last known pregnant; vaccination date; age of conceptus at vaccination; vaccination during the early embryonic, early fetal, and late fetal periods; and whether an early embryonic death (EED), early fetal loss (EFL), or late fetal loss (LFL) occurred. The relationships between the dichotomous outcomes of loss (eg, EED, EFL, LFL) and independent categoric variables (eg, vaccination during the early embryonic, early fetal, or late fetal periods) were examined. RESULTS: Vaccination of pregnant mares during any period of gestation was not associated with increased incidence of pregnancy loss. CONCLUSIONS AND CLINICAL RELEVANCE: Many mares are already pregnant at the onset of mosquito season, when mares are more likely to be vaccinated than at other times. Our findings provide evidence that vaccine administration will not compromise pregnancy in horses. 相似文献
17.
Long-Term Follow-up of Partial Limb Amputation in 13 Horses 总被引：1，自引：0，他引：1
GREGORY R. CRAWLEY DVM MS BARRIE D. GRANT DVM MS DiplomateACVs MELINDA K. KRPAN DVM MS MICHAEL D. MAJOR DVM 《Veterinary surgery : VS》1989,18(1):52-55
Thirteen cases of partial limb amputation in horses were reviewed. Nine horses (69%) survived 18 to 111 months (mean, 41 months). Four unsuccessfully treated horses were euthanatized within 21 days of surgery. The horses' ages at amputation were 4 to 13 years (mean, 7.3 years). There was no predilection for the left or right limb nor for fore or hind limb involvement. Osteomyelitis in six horses (46%) was the most common cause for amputation. Severe, open, comminuted fractures of the third metacarpal bone that were impossible to stabilize by any currently available technique in four horses (31%) were the second most common cause for amputation. One gelding was salvaged because of his sentimental value, two horses were used as breeding stallions, and six were broodmares. One stallion lived 30 months, completed two breeding seasons, and started a third. The other stallion began breeding, but became sterile. Three of the mares have produced five foals. One mare died while in foal. One mare aborted near-term twin fetuses and died of uterine hemorrhage. One mare aborted twice before the femoral head ligament on the contralateral limb ruptured, and she was euthanatized. 相似文献
18.
Measurement of urinary concentrations of the mycotoxins zearalenone and sterigmatocystin as biomarkers of exposure in mares 
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下载免费PDF全文 M Takagi S Uno E Kokushi F Sato MMP Wijayagunawardane J Fink‐Gremmels 《Reproduction in domestic animals》2018,53(1):68-73
Mycotoxins may affect animal health, including reproduction. Little is known about the clinical relevance of exposure of horses to contaminated feed. This study aimed at (i) monitoring the levels of the mycotoxins zearalenone (ZEN), with its metabolites α‐ and β‐zearalenol (α‐ and β‐ZOL), and sterigmatocystin (STC) in urine samples from thoroughbred mares in Japan and (ii) relating these findings to the potential effects on reproductive efficacy of breeding mares. Sixty‐three urine samples of breeding mares from 59 breeding farms were used. Urine samples and reproductive records were collected from each mare when it was presented to the stallion station. Urinary concentrations of ZEN, α‐ and β‐ZOL, and STC were measured using liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). ZEN, α‐ and β‐ZOL were measurable in the urine of all examined mares, indicating the prevalence of ZEN in equine feeds. In seven of the 63 samples, STC was also detected at levels ranging from 1.3 to 18.0 pg/mg creatinine. No significant correlation between the concentrations of mycotoxins and pregnancy status was observed. In conclusion, measurement of mycotoxins in urine samples is a useful non‐invasive method for monitoring the systemic exposure of mares to multiple mycotoxins. 相似文献
19.
Richard A. Mansmann Sarah JamesAnthony T. Blikslager DVM PhD DACVS Kurt vom Orde 《Journal of Equine Veterinary Science》2010
This study deals with the relationship between long toes in the hind feet and pain in the gluteal region in horses, and the remedial value of trimming/shoeing that moves the breakover point back at the toe. Seventy seven client-owned horses were studied, 67 shod riding horses retrospectively and 10 barefoot broodmares prospectively. The 10 mares were evaluated twice, and 24 of the 67 riding horses were re-evaluated at the next shoeing, for a total of 111 observations. Each horse underwent gluteal palpation and lateral radiographs of both hind feet. Toe length was quantified as breakover distance (BD), the horizontal distance between the tip of the third phalanx and the dorsalmost point at which the wall/shoe was in contact with the ground. The BD was then shortened with trimming +/− shoeing to a length of ≤15mm (shod horses) or ≤20 mm (barefoot horses). The 24 riding horses were re-evaluated 4-6 weeks later and the 10 broodmares 1 week after trimming. 相似文献
20.
The main purpose of this study was to investigate the relationship between MyHC and MyLC isoforms and the pedigree of the horses from different genetic background and gender. 26 Purebred Akhal-Teke horses (8 stallions and 18 mares) were used in this study, the horses belonged to 7 different sire lines and 9 different dam families. A muscle biopsy of depth 60 mm from the left gluteus medius muscle was obtained. The present study found the highest heritability for MyLC 1fast, MyLC 2slow and MyHC I isoform proportions, while only the first was statistically significantly different from zero. The mares had higher proportion of MyHC IIx and MyLC 3fast isoforms than the stallions. No statistically significant differences were found between sire lines and dam families. However, as the heritability of MyHC and MyLC in horses is found to be of moderate value, our study does not reject the hypothesis that it could be used as additional parameter in choosing the right animals for sport and breeding. 相似文献