Differentiation of four Indian aboriginal cattle populations revealed by STR markers

Cattle are the most important livestock in India and play a pivotal role in agrarian economy. There are 34 recognized breeds of cattle and number of unexplored lesser known populations. The present study is a contribution towards determining genetic variation and understanding the relationship among four lesser known populations. A total of 194 unrelated DNA samples from three cattle populations of Orissa (Binjharpuri, Ghumsuri, Motu) and Hill cattle of Kumaun (Kumauni) were collected from respective breeding tracts. Genotyping was done with 23 bovine microsatellite markers as suggested by International Society for Animal Genetics (ISAG) and FAO (DAD-IS) on automated sequencer. The average observed heterozygosity in the four populations lie within the narrow range of 0.623 +/- 0.04 in Binjharpuri to 0.664 +/- 0.03 in Kumauni. Mean estimates of observed and expected heterozygosity over all loci and breeds were 0.651 +/- 0.02 and 0.720 +/- 0.01, respectively. In the overall population, the homozygote excess (F(IT)) of 0.132 +/- 0.03, was partly due to the genetic differentiation among breeds (F(ST) = 0.044 +/- 0.01) and, to a larger extent, to a significant homozygote excess within breeds (F(IS) = 0.094 +/- 0.03). The phylogenetic reconstruction from a UPGMA clustering based on Nei's Standard genetic distance yielded a tree with Binjharpuri and Ghumsuri on a single node and Motu and Kumauni on separate nodes. The most probable clustering detected by STRUCTURE in population was three. Binjharpuri and Ghumsuri animals were assigned to one cluster with high proportion of membership.     

Transferrin (Tf) polymorphism in wild rabbit, Oryctolagus cuniculus

Evidence for two new alleles (TfC and TfD) at the transferrin locus (Tf) in wild rabbit, Oryctolagus cuniculus, is presented. Blood samples were collected in Continental Portugal (178 individuals), and in the Azores Islands of Terceira (52) and S. Miguel (59). The frequency of TfA, which is the only allele detected up to now in domestic rabbits, varied from 0.20 +/- 0.13 to 0.95 +/- 0.05 in the populations sampled in Continental Portugal. In the island populations sampled the frequency of TfA was greater than 0.8.     

Intensity of nematode infections in cyclic and non-cyclic rock partridge (Alectoris graeca saxatilis) populations

Populations of rock partridge (Alectoris graeca saxatilis), in the Trentino province of Italy, exhibit cyclic fluctuations in abundance associated with relatively dry habitat. One of the hypothesis to explain these cycles is that survival of some free living parasitic stages and rates of infection are greater in these areas leading to higher parasite burden. This hypothesis was examined by investigating the intensity of parasite infection in cyclic and non cyclic rock partridge populations. Analyses of 87 intestine samples collected from shot rock partridges during 1994 and 1995 identified 8 species of helminths parasites: Ascaridia compar (P = 33.33%; I = 9.28 +/- 1.78), Heterakis tenuicauda (P = 19.54%; I = 10.29 +/- 4.58), Heterakis gallinarum (P = 1.15%; I = 1.0 +/- 0.0), Heterakis altaica (P = 1.15%; I = 17 +/- 0.0), Aonchoteca caudinflata (P = 6.89; I = 2.17 +/- 0.65), Postharmostomum commutatum (P = 5.75; I = 7.0 +/- 3.48), Brachylaema fuscata (P = 1.15; I = 7.0 +/- 0.0), Platynosomum alectoris (P = 2.29; I = 5.5 +/- 1.5). Cestoda, recorded with a prevalence of 5.75, were not identified to species level. A. compar and H. tenuicauda were prevalent in the rock partridge populations and there was no positive association between these species. Intensity of infection in both species was not influenced by host age, sex or year of study but levels of infection with A. compar burdens were significantly greater in cyclic populations than in non cyclic populations and there was a tendency for H. tenuicauda to be greater in cyclic populations. There was no negative relationship between intensity of infection with A. compar or H. tenuicauda and host body mass. These data provide some support for the hypothesis that these parasites may play a role in generating rock partridge population cycles.     

Relationship between bronchopulmonary nematode larvae and relative abundances of Spanish ibex (Capra pyrenaica hispanica) from Castilla-La Mancha, Spain

The excretion of bronchopulmonary nematode infective larvae was evaluated in 160 faecal samples of Spanish ibex (Capra pyrenaica hispanica) collected from 13 populations in Castilla-La Mancha, south-central Spain in September 2003. Intensities and prevalences were compared with pasture availability, abundances of wild and domestic ungulates at both levels, i.e. for populations and for faeces in a two-step procedure. Protostrongylid larvae showed similar infection rates (mean intensity: 1.56+/-0.12, n=94; mean prevalence: 25.62+/-6.86%, n=160) to Dictyocaulus spp. (mean intensity: 1.03+/-0.11, n=48; mean prevalence: 30.00+/-7.11%, n=160). At the population level, positive correlations were found between the prevalences of both bronchopulmonary taxa. The prevalence in both groups, but not intensity, also correlated positively with Spanish ibex abundance indexes both for the populations and individual faeces. These findings suggest that: (i) parasite spreading across Spanish ibex populations in Castilla-La Mancha could respond to host density-dependent processes; and (ii) these populations may have similar exposition and/or susceptibility to both bronchopulmonary taxa resulting in similar host-parasite patterns, despite their different life cycles. Bronchopulmonary outputs in the Spanish ibex from Castilla-La Mancha seems not to represent a health risk for this endemic wild ungulate but may be useful in any health surveillance scheme for the increasing populations of Spanish ibex.     

Flow cytometric sorting of non-human primate sperm nuclei

Pre-determination of the sex of offspring has implications for management and conservation of captive wildlife species, particularly those with single sex-dominated social structures. Our goal is to adapt flow cytometry technology to sort spermatozoa of non-human primate species for use with assisted reproductive technologies. The objectives of this study were to: (i) determine the difference in DNA content between X- and Y-bearing spermatozoa (ii) sort sperm nuclei into X- and Y-enriched samples; and (iii) assess the accuracy of sorting. Spermatozoa were collected from two common marmosets (Callithrix jacchus), seven hamadryas baboons (Papio hamadryas) and two common chimpanzees (Pan troglodytes). Human spermatozoa from one male were used as a control. Sperm nuclei were stained (Hoechst 33342), incubated and analyzed using a high-speed cell sorter. Flow cytometric reanalysis of sorted samples (sort reanalysis, 10,000 events/sample) and fluorescence in situ hybridization (FISH; 500 sperm nuclei/sample) were used to evaluate accuracy of sorting. Based on fluorescence intensity of X- and Y-bearing sperm nuclei, the difference in DNA content between X and Y populations was 4.09 +/- 0.03, 4.20 +/- 0.03, 3.30 +/- 0.01, and 2.97 +/- 0.05%, for marmoset, baboon, chimpanzee and human, respectively. Sort reanalysis and FISH results were similar; combined data revealed high levels of purity for X- and Y-enriched samples (94 +/- 0.9 and 93 +/- 0.8%, 94 +/- 0.7 and 94 +/- 0.5%, 91 +/- 0.9 and 97 +/- 0.6%, 94 +/- 0.6 and 94 +/- 0.9%, for marmoset, baboon, chimpanzee and human, respectively). These data indicate the potential for high-purity sorting of spermatozoa from non-human primates.     

Flow cytometric DNA measurements in human thyroid tumors

By means of flow cytometry (FCM), DNA distribution pattern and the fraction of cells in the various phases of the cell cycle were studied in 52 samples of normal thyroid tissues, follicular adenomas, follicular carcinomas, medullary carcinoma and fibrosarcomas. In the normal thyroid tissues and follicular adenomas DNA diploid cell populations only were found. Among 20 follicular carcinomas in 13 cases (65%) together with the DNA diploid cells, DNA aneuploid cell lines were also observed. S-phase fraction in follicular adenomas is higher than in the normal thyroid tissues and lower than those in thyroid carcinomas. The percentage of S-phase cells in DNA aneuploid populations is significantly higher (S = 19 +/- 9.3%) than in the diploid cell lines (S = 3.7 +/- 2.6%). DNA aneuploid cell populations were predominantly observed in carcinomas with a high degree of morphological anaplasia.     

Effect of condensed tannins on bacterial diversity and metabolic activity in the rat gastrointestinal tract

The effect of dietary condensed tannins (proanthocyanidins) on rat fecal bacterial populations was ascertained in order to determine whether the proportion on tannin-resistant bacteria increased and if there was a change in the predominant bacterial populations. After 3 weeks of tannin diets the proportion of tannin-resistant bacteria increased significantly (P < 0.05) from 0.3% +/- 5.5% to 25.3% +/- 8.3% with a 0.7% tannin diet and to 47.2% +/- 5.1% with a 2% tannin diet. The proportion of tannin-resistant bacteria returned to preexposure levels in the absence of dietary tannins. A shift in bacterial populations was confirmed by molecular fingerprinting of fecal bacterial populations by denaturing gradient gel electrophoresis (DGGE). Posttreatment samples were generally still distinguishable from controls after 3.5 weeks. Sequence analysis of DGGE bands and characterization of tannin-resistant isolates indicated that tannins selected for Enterobacteriaceae and Bacteroides species. Dot blot quantification confirmed that these gram-negative bacterial groups predominated in the presence of dietary tannins and that there was a corresponding decrease in the gram-positive Clostridium leptum group and other groups. Metabolic fingerprint patterns revealed that functional activities of culturable fecal bacteria were affected by the presence of tannins. Condensed tannins of Acacia angustissima altered fecal bacterial populations in the rat gastrointestinal tract, resulting in a shift in the predominant bacteria towards tannin-resistant gram-negative Enterobacteriaceae and Bacteroides species.     

中间球海胆、光棘球海胆及杂交F1代（中间球海胆♀×光棘球海胆♂）群体遗传多样性AFLP分析

应用AFLP技术对中间球海胆、光棘球海胆及杂交F1代（中间球海胆♀×光棘球海胆♂）群体的遗传多样性进行了分析。结果表明,4对引物共扩增得到272个位点,其中269个多态位点,总的多态位点比例为98.89%。3个群体的香农多样性指数分别为：0.2331±0.1273、0.2005±0.1385和0.2625±0.1067。群体内遗传相似度分别为：0.6876±0.0523、0.6501±0.0548和0.6552±0.0553。分子方差分析（AMOVA）结果表明,变异来源有25.39%来自群体间,有74.61%来自群体内,群体内的遗传多样性比较丰富。尽管杂交海胆在表型上可以明显分成两种类型,但是通过AFLP统计的遗传距离进行的个体聚类却随机聚在一起,不能分成两个群体。     

Anisotropic and inhomogeneous tensile behavior of the human anulus fibrosus: experimental measurement and material model predictions

The anulus fibrosus (AF) of the intervertebral disc exhibits spatial variations in structure and composition that give rise to both anisotropy and inhomogeneity in its material behaviors in tension. In this study, the tensile moduli and Poisson's ratios were measured in samples of human AF along circumferential, axial, and radial directions at inner and outer sites. There was evidence of significant inhomogeneity in the linear-region circumferential tensile modulus (17.4+/-14.3 MPa versus 5.6+/-4.7 MPa, outer versus inner sites) and the Poisson's ratio v21 (0.67+/-0.22 versus 1.6+/-0.7, outer versus inner), but not in the axial modulus (0.8+/-0.9 MPa) or the Poisson's ratios V12 (1.8+/-1.4) or v13 (0.6+/-0.7). These properties were implemented in a linear an isotropic material model of the AF to determine a complete set of model properties and to predict material behaviors for the AF under idealized kinematic states. These predictions demonstrate that interactions between fiber populations in the multilamellae AF significantly contribute to the material behavior, suggesting that a model for th     

Wheat in bins and discharge spouts,and grain residues on floors of empty bins in concrete grain elevators as habitats for stored-grain beetles and their natural enemies

Wheat stored in upright concrete bins at seven grain elevators in central Kansas was sampled intermittently for insects over a 2.5-yr period by collecting samples from the upper half of the grain mass, from the discharge spout at the base of the bins, and from residue remaining in empty bins before the 2000 wheat harvest. Samples were taken from the grain mass with a power vacuum sampler (PV) and from the discharge spouts (DS) by dropping grain onto the reclaim belt beneath the bins. The density and species distribution in the residue samples were compared with those found in the DS samples and samples from the grain mass (PV). Cryptolestes spp. dominated the insect populations in all types of samples, constituting >40% of all insects in the PV samples in three of five time periods and >60% of all insects in DS samples in four of the five time periods. Cryptolestes spp. was an early colonizer, being found in the grain mass shortly after new grain was added. Rhyzopertha dominica appeared to be slower to colonize grain and grain residue, but sometimes developed large populations (i.e., 2.4 +/- 0.7 adults/kg between July and December 2000). Sitophilus spp. weevils often were present in grain masses, were often abundant in grain in the discharge spouts (i.e., 11.1 +/- 2.9 adults/kg between July and December 2000), and were abundant in grain residue in empty bins in May/June 2000 (5.3 +/- 0.7 adults/kg). Differences in density and species distribution of insects in grain in the upper part of the grain mass and those in the discharge spouts indicated that the populations were not closely related. Grain in discharge spouts usually was densely infested, and parasitic wasps, natural enemies of several of the beetles, were found when the density of the pest insects was greater than approximately 10/kg. The population of natural enemies appeared to increase when the density of pest insects increased after a lag of about one month, and decreased when the population of pest insects decreased. Grain in discharge spouts appeared to provide an incubation chamber for pest insects, and removing this grain periodically should reduce the resident populations. Residue in empty bins often was densely infested compared with samples from the grain masses. Cleaning the empty bins before refilling with newly-harvested wheat resulted in a significantly-reduced density of pest insects in discharge spouts later, and the effect lasted at least 12 wk after filling.     

Comparison of gastropod mollusc (Apogastropoda: Hydrobiidae) habitats in two crater lakes in Nicaragua

The aquatic gastropod mollusc, Pyrgophorus coronatus, may perform an important role in the transmission of an emergent ocular pathology among fishes in Lake Apoyo, Nicaragua. This disease emerged after an introduction of tilapia (Oreochromis niloticus) and the subsequent loss of Chara sp. beds in the lake. We compared the mollusc population densities in three habitats (sandy/muddy substrates, rocks, and Chara vegetation) at varying depths (1.5, 10, 20, and 30 m) in two volcanic crater lakes in Nicaragua: Lake Apoyo and Lake Xiloa. where lower numbers of affected fishes were found and tilapia has not been introduced. Duplicate samples at 1.5 m depth were taken in each habitat monthly for a year, and triplicate samples for bathymetric analysis of snail populations were performed during August, 2005. Samples of fixed surface area were filtered in a 0.4 cm size screen and live snails were counted from each sample. The preferred snail habitat in both lakes, Chara beds, was vastly reduced in Lake Apoyo via consumption by introduced Nile tilapia (Oreochromis niloticus). Structureless sandy substrates (mean +/- standard error 3.1+/-1.3 ind/m2) had lower population densities than other habitats in Lake Xiloa (rocks 590.9+/-185.3 ind/m2; vegetation 3 686.5+/-698.2 ind/m2; ANOVA 1, p<0.01 in both cases) but this difference was attenuated in Lake Apoyo (sand 384.4+/-111.1 ind/m2; rocks 1 480.4+/-384.8 ind/m2: 0.0 1相似文献   

Geographic variation in litter size in the cotton rat (Sigmodon hispidus): factors influencing ovulation rate

Litter size in many mammalian populations varies along a gradient of latitude or altitude. This investigation tested the hypothesis that geographic variation in litter size among populations of the cotton rat is the result of differences in ovulation rate. Oviducts and uteri of virgin and recently mated lab-reared descendants of cotton rats from Kansas (KS), Texas (TX), and Tennessee (TN) were flushed on the day following the last day of estrus. Ovulation rates differ significantly among the three populations for both virgins (mean +/- SEM, KS = 5.3 +/- 0.3, TX = 4.6 +/- 0.5, and TN = 4.0 +/- 0.5) and for females that have recently copulated (KS = 6.5 +/- 0.3, TX = 5.7 +/- 0.7, and TN = 3.7 +/- 0.4; P less than 0.001). These nonvirgin females have significantly higher ovulation rates than virgins for KS and TX (P = 0.01 and 0.05, respectively), but there is no significant effect of copulation on TN. In all populations, ovulation rates of rats that release ova from both ovaries (KS = 6.1 +/- 0.2, TX = 5.9 +/- 0.4, and TN = 5.1 +/- 0.5) are significantly higher than those that use only one ovary (KS = 4.4 +/- 0.4, TX = 3.3 +/- 0.4, and TN = 3.2 +/- 0.3; P less than 0.001). The number of ovaries ovulating differs significantly between populations (P = 0.002). The effect of copulation on the number of ovaries ovulating is marginally significant (P = 0.08).(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of seminal quality in Holstein bulls as yearlings and as mature sires

Semen quality was compared in 5 Holstein bulls from samples collected as young sires (yearlings) and again as mature bulls after a mean interval of 1,265 d. At both sampling periods, the semen was examined for ejaculate volume, sperm numbers, post-thaw progressive motility and sperm viability. Sperm viability was assessed on cryopreserved samples with fluorescent SYBR-14 to stain living spermatozoa and propidium iodide (PI) to identify dead spermatozoa. The fluorescent populations of stained spermatozoa were quantified by flow cytometry. The percentages of living spermatozoa for the individual bulls, as determined by green fluorescence of SYBR-14, ranged from 44 +/- 3.1 to 54 +/- 0.3 for yearlings, and from 38 +/- 1.5 to 55 +/- 1.0 for mature sires. No differences in sperm viability were found between samples taken from yearling bulls and those of mature bulls. The percentage of spermatozoa stained with SYBR-14 was negatively correlated (r = -0.97; P = 0.0001) with the percentage of dead spermatozoa as indicated by PI staining. Comparisons of identical samples run on 2 different flow cytometers indicated that either flow instrument could be used to assess sperm viability. Although the individual bulls differed (P < 0.05) in ejaculate volume and sperm numbers as yearlings, they did not differ in these parameters as mature bulls. The average number of spermatozoa per ejaculate changed as a result of maturation, increasing from 6.2 +/- 1.0 to 10.7 +/- 1.1 x 10(9). Aging was significantly correlated with ejaculate volume (r = 0.76; P = 0.01) but not with the total number of spermatozoa per ejaculate (r = 0.51; P = 0.13). The maturational changes that occurred in the 5 bulls were minimal with the exception of the increased volume of the ejaculate and the number of spermatozoa per ejaculate.     

Phenotypic analysis of a large number of normal human bone marrow sample by flow cytometry

Bone marrow aspirates from 48 healthy donors (34 adults, 14 children) were analyzed by flow cytometry (FACS Analyzer) after purification of low-density bone marrow cells (Ld BMC) on a density gradient (d = 1,077) and labelling with 23 anti-hematopoietic cell monoclonal antibodies. Based on physical properties, these Ld BMC could be divided into four different populations called E, My, Mo and L, which comprised 14% +/- 9%, 31% +/- 16%, 10% +/- 5% and 45% +/- 14% of these cells, respectively. The phenotypic analysis of these different populations enabled the identification in E, of erythrocytes (Glycophorin A+, Rhesus D+, but negative for early erythroid differentiation markers such as the transferrin receptor (Tf. R) and the FA6-152 antigen); in My of cells of the myeloid lineage (VIM2+, HLA DR-); in Mo of cells of the monocytic lineage (VIM2+, CD14+) plus some myeloblasts (VIM2+, CD14-, HLADR+) and finally in L of a heterogeneous population including: 1. T lymphocytes labelled to the same extent by CD2, CD3, CD5 and CD6 (28% +/- 10%), B lymphocytes assessed by CD19 and CD20 (12% +/- 8%), Pre-B cells (CD10+ = 8% +/- 7%), less than 5% of "natural killer" cells (CD16+ or Leu7+) and finally, less than 6% of myelomonocytes (CD14+ and/or VIM2+). 2. The erythroid lineage (rhesus D+ = 42% +/- 20%, Tf.R+ and FA6-152+ = 32% +/- 12%). 3. Undifferentiated cells or progenitor cells (CD34+ = 7% +/- 5%). 4. Cells unlabelled by any antibodies (approximately 6%). We observed no difference between bone marrow samples from adults or children, with respect to physical properties, and with all but four immunological markers. A significantly higher proportion of B cells (CD19+ and CD10+) (P less than 0.001) and undifferentiated cells (CD34+ and HLADR+) (P less than 0.02) was observed in children. These data, obtained from a large number of bone marrow samples, could be used to quantify the imbalance of some bone marrow disorders.     

The effect of the genetic polymorphisms of CYP1A1,CYP2D6, GSTM1 and GSTP1 on aromatic DNA adduct levels in the population of healthy women

Aromatic DNA adduct levels and polymorphisms of two phase I enzymes - CYP1A1 and CYP2D6 and two phase II enzymes - GSTM1 and GSTP1 were analyzed in a group of 133 nonsmoking healthy women 35-45 years old and holding jobs not connected with the exposure to the combustion products of organic matter. They were office workers from the south and north-eastern parts of Poland. Blood samples were collected in winter and in summer. Aromatic DNA adduct levels were measured in all winter and summer samples. The frequencies of CYP1A1, CYP2D6, GSTM1 and GSTP1 polymorphisms in samples from the studied women did not show any differences when compared with other Caucasian populations and the Polish male population studied previously. The differences in the levels of DNA adducts among the carriers of different genotypes were statistically non-significant. Analysis of combined genotypes selected the groups of volunteers with the highest and the lowest DNA adduct levels. The highest levels of DNA adducts were observed in the carriers of GSTM1(null)/CYP1A1Ile/Val (8.00+/-13.00 adducts/10(8) nucleotides in summer samples) and GSTP1-AA/CYP1A1Ile/Val genotypes (7.00+/-4.32 in winter and 7.30+/-7. 27/10(8) nucleotides in summer). The lowest levels of DNA adducts (3. 00+/-2.30 in winter and 2.00+/-3.16/10(8) nucleotides in summer) were found in the carriers of the genotype GSTP1-AG+GG/CYP1A1Ile/Val. The levels of DNA adducts in these groups were determined by the polymorphisms of GSTM1 and GSTP1 phase II detoxifying enzymes.     

Genetic polymorphism of mitochondrial DNA HVS-I and HVS-Ⅱ of Chinese Tu ethnic minority group

We analyzed the two hypervariable segments HVS-Ⅰ and HVS-Ⅱ of 108 Chinese Tu ethnic minority group samples for forensic and population genetics purposes.Comparing with Anderson sequence,79 polymorphic loci in HVS-Ⅰ and 40 in HVS-Ⅱ were found in Chi-nese Tu ethnic minority group mtDNA sequences,and 90 and 64 haplotypes were then defined.Haplotype diversity and the mean pair-wise differences were 0.9903±0.0013 and 5.7785 in HVS-Ⅰ,and 0.9777±0.0013 and 3.5819 in HVS-Ⅱ,respectively.By analyzing the hypervariable domain from nucleotide 1,6180 to 1,6193 in HVS-Ⅰ,we defined some new types of sequence variations.We also compared the relationship between Tu population and other populations using mtDNA HVS-Ⅰ sequences.According to Rst genetic distances,the phylogenetic tree showed that the Tu population,the Xi'an Han population,the Chinese Korean,and the Mongol ethnic group were in a clade.This indicated a close genetic relationship between them.There were far relations between the Tu population and other Chinese southern Han populations,Siberian,European,African,and other foreign populations.The results suggest that Tu population has a multi-origin and has also merged with other local populations.     

Sperm creatine phosphokinase activity as a measure of sperm quality in normospermic, variablespermic, and oligospermic men

We have found a significant inverse correlation between sperm concentrations and sperm creatine N-phosphotransferase (CPK) activities in oligospermic and normospermic human specimens. In the present work, we carried out serial CPK determinations to assess whether there is a relationship between fluctuating sperm concentrations and sperm quality in consistently oligospermic and variablespermic (sperm concentrations are occasionally in the greater than 20 million/ml range) husbands of 65 couples (23 normospermic men/51 samples, 25 consistently oligospermic men/80 samples, and 17 variablespermic men/68 samples). The sperm CPK activities were significantly lower in the normospermic vs. the oligospermic or variablespermic groups (p less than 0.001), but there were no differences between the latter two (p greater than 0.25). The mean CPK values of migrated sperm fractions in both the oligospermic and variablespermic populations were improved (at least 20% decline in CPK values) compared to those of the initial specimens (1.27 +/- 0.38 vs. 0.68 +/- 0.37 and 0.77 +/- 0.32 vs. 0.46 +/- 0.24 SEM U/100 million sperm, respectively, p less than 0.001 in both pairs) and the incidence of the "failed-to-improve" samples was also similar in the two groups (44/36 vs. 45/23, p greater than 0.2). The lack of differences in the mean CPK activities, in the distribution of CPK values under and over 0.250 U/100 million sperm level, and in the ratio of migrated samples with improved or with failed-to-improve CPK activities suggests that sperm quality is not different between men who are consistently oligospermic and those who occasionally produce normospermic specimens.(ABSTRACT TRUNCATED AT 250 WORDS)     

Worldwide patterns of mitochondrial DNA differentiation in the harbor seal (Phoca vitulina)

The harbor seal (Phoca vitulina) has one of the broadest geographic distributions of any pinniped, stretching from the east Baltic, west across the Atlantic and Pacific Oceans to southern Japan. Although individuals may travel several hundred kilometers on annual feeding migrations, harbor seals are generally believed to be philopatric, returning to the same areas each year to breed. Consequently, seals from different areas are likely to be genetically differentiated, with levels of genetic divergence increasing with distance. Differentiation may also be caused by long-standing topographic barriers such as the polar sea ice. We analyzed samples of 227 harbor seals from 24 localities and defined 34 genotypes based on 435 bp of control region sequence. Phylogenetic analysis and analysis of molecular variance showed that populations in the Atlantic and Pacific Oceans and east and west coast populations of these oceans are significantly differentiated. Within these four regions, populations that are geographically farthest apart generally are the most differentiated and often do not share genotypes or differ in genotype frequency. The average corrected sequence divergence between populations in the Atlantic and Pacific Oceans is 3.28% +/- 0.38% and those among populations within each of these oceans are 0.75% +/- 0.69% and 1.19% +/- 0.65%, respectively. Our results suggest that harbor seals are regionally philopatric, on the scale of several hundred kilometers. However, genetic discontinuities may exist, even between neighboring populations such as those on the Scottish and east English coasts or the east and west Baltic. The mitochondrial data are consistent with an ancient isolation of populations in both oceans, due to the development of polar sea ice. In the Atlantic and Pacific, populations appear to have been colonized from west to east with the European populations showing the most recent common ancestry. We suggest the recent ancestry of European seal populations may reflect recolonization from Ice Age refugia after the last glaciation.      

Variation in mitochondrial DNA in Far Eastern mullet pilengas, Liza haematocheilus Temminck and Schlegel, acclimatized in the Azov-Black Sea basin

This study continues the investigation of genetic variation in the populations of native and acclimatized in the Azov-Black Sea basin pilengas from the Sea of Japan. The previous comparison based on allozyme analysis was supplemented by analysis of restriction polymorphism of a mitochondrial DNA fragment containing the cytochrome b gene and the D-loop. Five out of fifteen endonucleases tested detected polymorphic sites. In the samples of native and acclimatized pilengas, five common haplotypes were found; ten and three "population-specific" haplotypes were detected in the Far Eastern and the Azov populations, respectively. The differences in haplotype distributions between these populations were highly significant (P < 0.001). The mtDNA variation was lower in the Azov than in the Far Eastern population (haplotype diversity mu respectively 6.35 +/- 0.27 and 9.14 +/- 0.55), which is in good agreement with the decrease in the number of polymorphic loci and the mean number of alleles per locus, found earlier for allozyme markers in this population. The reasons for these differences in the acclimatized population are discussed.