scholarly journals Assessment of line differentiation in the Thoroughbred horse breed using DNA microsatellite loci

2019 ◽  
Vol 23 (5) ◽  
pp. 569-574 ◽  
Author(s):  
L. A. Khrabrova ◽  
N. V. Blohina ◽  
O. I. Suleymanov ◽  
G. А. Rozhdestvenskaya ◽  
V. F. Pustovoy

The Thoroughbred (TB) horse is the best racehorse breed used in the racing industry. This breed has had a closed studbook for about 300 years. In Russia TB horses have been bred since the second half of the XVIII century. The modern Russian Stud Book register of TB horses is partially presented by stallions and broodmares imported from different countries. The genealogical structure of the breed is represented by 17 lines, among which the Northern Dancer line dominates (30.9 %). The study of features of different lines of TB was carried out on 17 loci of DNA microsatellites (VHL20, HTG4, AHT4, HMS7, HTG6, AHT5, HMS6, ASB23, ASB2, HTG10, HTG7, HMS3, HMS2, ASB17, LEX3, HMS1 and CA425) to assess genetic differentiation of the genealogical structure. The results of the DNA typing of 8091 Thoroughbred horses across microsatellite loci show that the gene pool of the domestic population is represented by 100 alleles typical of the breed. A comparative analysis of the genotypes of horses representing different lines indicates that they differ in the number of alleles (85–99), allele frequencies, the level of polymorphism Ae (2.93–3.48) and the degree of the observed heterozygosity Ho (0.653–0.739). The genetic distances between the lines varied in a wide range from 0.014 (Nasrullah – Northern Dancer) to 0.125 (Massine – Teddy). The correspondence to HWE was maintained in most lines, which is confirmed by the negative values of Fis. Cluster analysis demonstrated the correspondence of the obtained dendrogram of Nei’s genetic distances to its genealogical scheme of lines. Genetic differentiation of lines by index Fst varied in a range 0.005–0.073 at the mean value Fst = 0.024. The data indicate genetic differentiation of lines of TB at the STR markers and confirm the effectiveness of the system of linear breeding for the maintenance of interbreed biodiversity.

Genetika ◽  
2015 ◽  
Vol 47 (3) ◽  
pp. 1123-1130 ◽  
Author(s):  
Elizabeta Miskoska-Milevska ◽  
Zoran Popovski ◽  
Blagica Dimitrievska ◽  
Katerina Bandzo

Commonly used method for determination of the genetic diversity among the populations is the test for genetic differentiation. DNA microsatellite markers are usually used to investigate the genetic structure of natural populations. The aim of this study was to evaluate the applicability of eight DNA microsatellite loci (LECH13, LE21085, LEMDDNa, LEEF1Aa, LELEUZIP, LE20592, TMS9 and LE2A11) in genetic differentiation of six morphologically different tomato varieties (var. grandifolium from subsp. cultum; var. cerasiforme - red and yellow, var. pruniforme and var. pyriforme from subsp. subspontaneum; and var. racemigerum from subsp. spontaneum). The fragment analyses was performed using Applied Biosystems DNA analyzer (ABI 3130) and GeneMapper? Software program. The data were analysed using the specific program Power Marker Software. The average number of detected alleles was 3,625. Also, the average PIC value for all 8 DNA microsatellites loci was 0,3571. The genetic differentiation test in the researched tomato subspecies showed minor differentiation for locus LELEUZIP (- 0,0009), modest differentiation for locus LECH13 (0,0896), locus LEMDDNa (0,0896) and locus LE21085 (0,0551) and major differentiation for locus LE2A11 (0,7633), locus LEEF1Aa (0,6167), locus TMS9 (0.4967) and locus LE20592 (0,4263). On the other hand, in the estimated tomato varieties, locus LE21085 (0,0297), locus LECH13 (0,0256) and locus LELEUZIP (0,0005) showed minor differentiation, locus LEMDDNa (0,1333) showed modest differentiation, while locus TMS9 (0,5929), locus LEEF1Aa (0,5006), locus LE2A11 (0,4013) and locus LE20592 (0,2606) showed major differentiation. The eight DNA microsatellite loci can be applicable solution for tomato genetic differentiation. The overall results suggest that these microsatellite loci could be used in further population genetic studies of tomatoes.


2018 ◽  
Vol 7 (4) ◽  
pp. 13-21
Author(s):  
Todd Backes ◽  
Charlene Takacs

There are a wide range of options for individuals to choose from in order to engage in aerobic exercise; from outdoor running to computer controlled and self-propelled treadmills. Recently, self-propelled treadmills have increased in popularity and provide an alternative to a motorized treadmill. Twenty subjects (10 men, 10 women) ranging in age from 19-23 with a mean of 20.4 ± 0.8 SD were participants in this study. The subjects visited the laboratory on three occasions. The purpose of the first visit was to familiarize the subject with the self-propelled treadmill (Woodway Curve 3.0). The second visit, subjects were instructed to run on the self-propelled treadmill for 3km at a self-determined pace. Speed data were collected directly from the self-propelled treadmill. The third visit used speed data collected during the self-propelled treadmill run to create an identically paced 3km run for the subjects to perform on a motorized treadmill (COSMED T150). During both the second and third visit, oxygen consumption (VO2) and respiratory exchange ratio (R) data were collected with COSMED’s Quark cardiopulmonary exercise testing (CPET) metabolic mixing chamber system. The VO2 mean value for the self-propelled treadmill (44.90 ± 1.65 SE ml/kg/min) was significantly greater than the motorized treadmill (34.38 ± 1.39 SE ml/kg/min). The mean R value for the self-propelled treadmill (0.91 ± 0.01 SE) was significantly greater than the motorized treadmill (0.86 ± 0.01 SE). Our study demonstrated that a 3km run on a self-propelled treadmill does elicit a greater physiological response than a 3km run at on a standard motorized treadmill. Self-propelled treadmills provide a mode of exercise that offers increased training loads and should be considered as an alternative to motorized treadmills.


Author(s):  
V. Dodokhov ◽  
N. Pavlova ◽  
T. Rumyantseva ◽  
L. Kalashnikova

The article presents the genetic characteristic of the Chukchi reindeer breed. The object of the study was of the Chukchi reindeer. In recent years, the number of reindeer of the Chukchi breed has declined sharply. Reduced reindeer numbers could lead to biodiversity loss. The Chukchi breed of deer has good meat qualities, has high germination viability and is adapted in adverse tundra conditions of Yakutia. Herding of the Chukchi breed of deer in Yakutia are engaged only in the Nizhnekolymsky district. There are four generic communities and the largest of which is the agricultural production cooperative of nomadic tribal community «Turvaurgin», which was chosen to assess the genetic processes of breed using microsatellite markers: Rt6, BMS1788, Rt 30, Rt1, Rt9, FCB193, Rt7, BMS745, C 143, Rt24, OheQ, C217, C32, NVHRT16, T40, C276. It was found that microsatellite markers have a wide range of alleles and generally have a high informative value for identifying of genetic differences between animals and groups of animal. The number of identified alleles is one of the indicators of the genetic diversity of the population. The total number of detected alleles was 127. The Chukchi breed of deer is characterized by a high level of heterozygosity, and the random crossing system prevails over inbreeding in the population. On average, there were 7.9 alleles (Na) per locus, and the mean number of effective alleles (Ne) was 4.1. The index of fixation averaged 0.001. The polymorphism index (PIC) ranged from 0.217 to 0.946, with an average of 0.695.


1961 ◽  
Vol 38 (4) ◽  
pp. 695-705
Author(s):  
J. B. BALINSKY ◽  
E. BALDWIN

1. Eighty-two single determinations of ammonia and urea excretion by Xenopus laevis indicated that the percentage of ammonia varied from 40 to 80%, with a mean value of 62%. 2. Measurements of excretion on successive days after feeding showed that a large amount of ammonia was produced soon after feeding, but that ammonia excretion declined rapidly. Urea excretion, not so high initially, remained more or less constant until the third or fourth day, often exceeding ammonia excretion at that time. Thereafter, it also declined and the excretion of both substances reached a constant starvation level by the fifteenth day. 3. Both ammonia and urea excretion were equally affected by temperature. The Q10's were near 2 in the range 20-30° C., but greater in the range 10-20° C. 4. At least 86% of ammonia, and 81% of urea were excreted through the cloaca. 5. The mean 24 hr. urine output of Xenopus at 20% C. was 23.6 ml. per 100 g. body weight. 6. Although the blood ammonia concentration did not appear to be zero, the urine/blood concentration ratio of ammonia was greater than 100. The urine/blood concentration ratio of urea was not significantly different from unity, and constant over a very wide range of concentrations. 7. The above result is interpreted to indicate passive glomerular filtration of urea, and little or no tubular reabsorption of water. 8. It is suggested that ammonia is formed in the kidney, and actively secreted into the glomerular filtrate.


1991 ◽  
Vol 70 (5) ◽  
pp. 1991-1995 ◽  
Author(s):  
S. A. Gu ◽  
J. Ducas ◽  
U. Schick ◽  
R. M. Prewitt

We investigated the effects of hypoxic ventilation on the pulmonary arterial pressure- (P) flow (Q) relationship in an intact canine preparation. Mean pulmonary P-Q coordinates were obtained during hypoxic ventilation and during ventilation with 100% O2 at normal and at increased left atrial pressure. Specifically, we tested the hypothesis that, over a wide range, changes in left atrial pressure would alter the effects of hypoxic ventilation on pulmonary P-Q characteristics. Seven dogs were studied. When left atrial pressure was normal (5 mmHg), the mean value of the extrapolated intercept (PI) of the linear P-Q relationship was 10.9 mmHg and the slope (incremental vascular resistance, IR) of the P-Q relationship was 2.2 mmHg.l-1.min. Hypoxic ventilation increased PI to 18 mmHg (P less than 0.01) but did not affect IR. Subsequently, during ventilation with 100% O2, when left atrial pressure was increased to 14 mmHg by inflation of left atrial balloon, PI increased to 18 mmHg. IR was 1.6 mmHg.l-1.min. Again, hypoxic ventilation caused an isolated change in PI. Hypoxia increased PI from 18 to 28 mmHg (P less than 0.01). As in the condition of normal left atrial pressure, hypoxic ventilation did not affect IR. We conclude that, in an anesthetized intact canine preparation, hypoxic ventilation causes an isolated increase in the extrapolated pressure intercept of the pulmonary P-Q relationship. Furthermore the effects of hypoxic ventilation on pulmonary P-Q characteristics are not affected by the resting left atrial pressure.


Author(s):  
J. Van den Bosch ◽  
C.F. Mercer

Clover cyst nematode (Heterodera trifolii) reduces growth and nutrient uptake of white clover (Trifolium repens) in New Zealand, and breeding resistant cultivars is the preferred control method for ecological and economic reasons. Resistant and susceptible selections were taken from a wide range of white clover seedlines. Selected plants were intercrossed and reselected over two cycles of selection. Cysts per gram of root dry weight (cysts/ g) was the measure of resistance used, with low cysts/g plants being more resistant. The mean cysts/ g value of the progenies from resistant parents was 69% of the mean value of the progenies from susceptible parents in the first generation, and 38% in the second generation. Root weights were similar, while the resistant selections had 58% and 34% (first and second generations respectively) of the number of cysts in the susceptible selections. There were no immune plants (0 cysts) in the first generation and only two in the second. Counts were made of cysts, eggs per cyst and eggs per plant on clones of two resistant and two susceptible genotypes. The resistant genotypes had lower counts than the susceptible genotypes in terms of cysts per plant (means of 6 cf. 108), eggs per cyst (11 cf. 21) and eggs per plant (35 cf. 1650). The differences in numbers of cysts between resistant and susceptible lines increased during two generations of selection, supporting earlier results that indicated that progress in breeding for resistance was possible. Furthermore, the resistance is also acting on clover cyst nematode egg production which would further reduce recruitment to later generations of clover cyst nematode. Keywords: breeding, Heterodera trifolii, resistance, screening, selection, Trifolium repens


Author(s):  
Carlos A. Hernández J. ◽  
Klaus Gocke

Between January 1987 and January 1988 the primary productivity and related parameters were studied in the Ciénaga Grande de Santa Marta. The Ciénaga is a coastal lagoon with an area of 423 km'2 and mean depth of 1.6 m, which is located at the Caribbean coast of Colombia. The salinity fluctuates seasonally within a wide range. The system is characterized by a high concentration of seston and a great primary productivity. The concentration of chlorophyll " a " ranged from 5.6to 181 ug Ii , the mean value was 59 ug I i . The concentration of proteins was within the extremes of 0.9 and 9.5 mg I"i f the mean value was 4.2 mg I ] . The gross primary productivity in the central part of the Ciénaga amounted to 1690 g C m*2 per year. Considering the temporal fluctuation in the whole system the lowest and highest values were 1.40 and 16.3 g C rrr2 per day. Highest productivity values were encountered when the salinity was low. The primary productivity is controlled by water turbidity and availability of nutrients, thus, seasonal continental waters. The photosynthetic laver ¡s restricted to less than 1.5 m due to the high particle concentration. The mean N: P relation was 4:1 which indicates that the nitrogen compounds are the limiting nutrientes. The high primary productivity sustains an important local fishery. The coastal area in the vicinity of the Ciénaga Grande is benefitted by the export of particulated and dissolved organic matter produced in excess within the coastal lagoon.


2020 ◽  
Author(s):  
Leah E. Morgan

Abstract. 40Ar/39Ar and K-Ar geochronology assume that 40K/K values are invariant among the sample of interest, the co-irradiated neutron fluence monitor (standard), and the material used to measure decay constants. Until recently, this assumption was reasonable due to the small K isotope (41K, 40K, 39K) variability found in many terrestrial samples and the negligible effect of any variation relative to the precision of the determined age. The recent discovery of measurable δ41K variability in terrestrial samples now questions this assumption. Although δ41K values for some neutron fluence monitors have now been reported, potassium isotopes are not routinely measured on samples dated by the 40Ar/39Ar method even though a wide range of silicate materials were found to vary by > 2.5 ‰. Further, the 40K decay constants used in 40Ar/39Ar geochronology are based on activity counting of radioactive decay in K-rich salts. These salts have not been measured for δ41K, yet evaporites have been shown to vary by > 1 ‰ from the mean value of silicates. The potential effects of δ41K variability on 40Ar/39Ar ages are illustrated using the case of the ca. 28.2 Ma Fish Canyon sanidine (FCs) and the ca. 99 Ma Mt. Dromedary Biotite (GA-1550). If the two standards have δ41K values as measured and the material used to determine decay constants is appropriately represented by δ41K of evaporites, the age of FCs is underestimated by ca. 7 ka (0.25 ‰). Although this is a small effect, such bias is becoming important as the analytical precision and accuracy of isotopic measurements and calculation of 40Ar/39Ar ages continue to improve.


2011 ◽  
Vol 56 (No. 4) ◽  
pp. 163-175 ◽  
Author(s):  
L. Vostrý ◽  
O. Kracíková ◽  
B. Hofmanová ◽  
V. Czerneková ◽  
T. Kott ◽  
...  

The Old Kladruber horse is the oldest original Czech horse breed &ndash; gene resource, with pedigree records spanning three centuries. Because the population is closed, there is a concern about the loss of genetic variation. The genetic diversity within and amongst sire lines was evaluated using microsatellite markers and based on pedigree information. The DNA analysis, covering 16 microsatellite loci, revealed that the genetic diversity (observed heterozygosity = 0.637, genetic diversity = 0.678 and the mean number of alleles = 8.25) for the Old Kladruber horse is consistent with other populations of horses. Inter-line genetic difference in sire lines reached the mean value (the F<sub>ST</sub> values ranged from 0.020 to 0.017). Differences amongst the sire lines were identified using genetic distances and principal component analysis. One gene cluster comprised black variation sire lines, while the second cluster included the sire lines of the grey variation. In the subjects monitored, the average inbreeding coefficient of 0.076 was estimated on the basis of pedigree information. The highest mean values of the coefficient of relationship were estimated within the colour variations. When comparing the genetic distance and the average coefficient of relationship, differences were found out. These results are useful for the development of breeding strategies which consider classical horse breeding as well as recent achievements of population and conservation genetics.


2010 ◽  
Vol 17 (5) ◽  
pp. 836-839 ◽  
Author(s):  
Daniel J. Hackett ◽  
Changpin Zhang ◽  
Carla Stefanescu ◽  
Robert F. Pass

ABSTRACT Measurement of antibody to cytomegalovirus (CMV) glycoprotein B (gB) is valuable in the assessment of the antibody response to infection and to gB-containing vaccines. For this purpose, an enzyme-linked immunosorbent assay (ELISA) with a recombinant CMV gB molecule as the antigen was evaluated. Sera from 168 anti-CMV IgG-positive and 100 seronegative subjects were used to evaluate the anti-gB antibody assay. A cutoff optical density (OD) that would distinguish gB antibody-positive from -negative sera was established. Titers of antibody to gB determined by endpoint dilution were compared with those calculated using regression analysis. The run-to-run and interoperator reproducibilities of results were measured. The mean OD + 5 standard deviations from 50 anti-CMV IgG antibody-negative sera (0.2472) was used as the cutoff between anti-gB antibody-positive and -negative results. All sera from 100 anti-CMV IgG-seronegative subjects were negative for antibody to gB. All but 1 of 168 sera from seropositive subjects were positive for antibody to gB. Observed antibody levels based on titration to the endpoint were very similar to results calculated using linear regression. The run-to-run consistency of endpoints was excellent, with 38 runs from one operator and 48 runs from another all giving results within 1 dilution of the mean value for each of three anti-CMV IgG antibody-positive serum pools. The geometric mean titer of antibody to gB for 99 sera from seropositive blood donors was 1/10,937. This ELISA gives accurate and reproducible results for the relative quantity of anti-CMV gB IgG in serum over a wide range of antibody levels.


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