bluuebunny/crossref_metadata_2025_split huggingface dataset:
Social and Breed Effects on the Expression of a PGF2α Induced Oestrus in Beef Cows
Authors: Landaeta‐Hernández AJ , Palomares‐Naveda R , Soto‐Castillo G , Atencio A , Chase CC , Chenoweth PJ 
Published: September 2004

ContentSocial organization and breed effects following PGF2αwere studied in mature Angus, Brahman and Senepol cows allocated into two groups (each A = 5, B = 5 and S = 5). Variables including interval to oestrus onset (IEO), oestrous duration (DE), total mounts received (TMR), and oestrous intensity (IE) were derived via HeatWatch®. Breed‐type influenced IEO (B = 42.6 ± 6.7 h; S = 54.6 ± 6.0 h; and A = 27.8 ± 5.8 h; p < 0.003). Within breeds, dominant B (69.4 ± 13.3 h) and S (65.5 ± 7.4 h) cows were slower (p < 0.05) to be detected in oestrus than subordinate (38.1 ± 4.4 h) and intermediate (40.6 ± 6.0 h). However, within A, dominant cows (16.4 ± 12.5 h) were detected in oestrus earlier (p < 0.05) than intermediate (44.3 ± 9.2 h) and subordinates (32.7 ± 5.1 h). Angus (21.5 ± 2.4 h) and B (22.1 ± 3.0 h) cows had longer (p < 0.01) DE than S (9.1 ± 2.8 h). Dominants (20.4 ± 3.0) and intermediates (20.2 ± 2.3 h) cows had longer DE (p < 0.04) than subordinates (12.1 ± 2.1 h) although the interaction breed × social order showed that dominant S had shorter DE than dominant A and B (10.1 ± 3.3; 34.8 ± 6.0 h; and 20.0 ± 6.4 h, respectively; p < 0.001). Angus cows had less TMR than B (p < 0.02) and tended to be less than S cows (p < 0.06). Overall, greatest (p < 0.008) IE occurred in the first 9 h after onset of oestrus with no breed effect (p > 0.05). Dominant cows tended (p < 0.10) to have less TMR (3.2 ± 0.7 mounts) than subordinate (4.1 ± 0.4 mounts) and intermediate (4.7 ± 0.6 mounts) throughout, especially 3–6 h after oestrus onset (p < 0.07). Breed and social order both influence PGF2α‐induced oestrus behaviour.
Expression Pattern of Fibroblast Growth Factor (FGF) and Vascular Endothelial Growth Factor (VEGF) System Members in Bovine Corpus Luteum Endothelial Cells During Treatment with FGF‐2, VEGF or Oestradiol
Authors: Gabler C , Plath‐Gabler A , Killian GJ , Berisha B , Schams D 
Published: September 2004

ContentsThe development of the corpus luteum (CL) is accompanied by very active angiogenesis. We hypothesize that during this process endothelial cells (EC) are under the control of several angiogenic factors and steroids. The aim of this study was to examine the expression of the angiogenic growth factor systems – fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) – in EC derived from the bovine CL. Endothelial cells were cultured in serum‐free medium and treated for 24 h with different concentrations of oestradiol (range from 10−13 to 10−5 mol/l), VEGF or FGF‐2 (1, 10 and 100 ng/ml, respectively) and compared with untreated controls. Cells were harvested, total RNA extracted and subjected to semi‐quantitative reverse transcriptase‐polymerase chain reaction (RT‐PCR). Treatment with oestradiol or FGF‐2 stimulated the expression of FGF‐2, but VEGF treatment showed no effect on the FGF‐2 expression. FGF‐2 or VEGF treatment resulted in an up‐regulation of the FGF receptor (FGFR) mRNA. However, no FGF‐1 expression was detected in EC. For the VEGF system, treatment with FGF‐2, VEGF or oestradiol did not affect VEGF expression. However, the presence of FGF‐2 in the medium up‐regulated the expression of both VEGF receptors (VEGFR‐1 and VEGFR‐2), whereas oestradiol or VEGF treatment showed no effect on the expression of these receptors. Our results reveal that functional angiogenic growth factor systems were expressed in vitro in bovine EC derived from the CL. This suggests that the angiogenic FGF and VEGF system members were regulated by FGF or VEGF, but not by oestradiol‐17β.
Preliminary Trial: Motility Comparisons of a Unique Freezing Technology (UFT) to Liquid Nitrogen Mist Methodology for Cryopreservation of Porcine Spermatozoa
Authors: Goolsby HA , Blanton JR , Cotter PZ , Prien SD 
Published: September 2004

ContentsThe motility outcomes of boar semen frozen with newly developed freezing techniques using a new unique freezing technology (UFT) compared with traditional liquid nitrogen methodology were investigated with the intent of improving current fertility outcomes using semen. The UFT is an electronically controlled cooling chamber that houses an organic fluid bath that can be maintained at temperatures below 0°C without solidifying to freeze samples. Four ejaculates from four different boars were collected for this trial. Samples were handled consistently during the pre‐ and post‐freeze processing. From each ejaculate, samples were separated into eight cryopreservation treatment groups, six UFT variations and two control liquid nitrogen groups, immediately before freezing, in replicates of two. After the initial cryopreservation was complete, all samples were stored in liquid nitrogen for at least 48 h. Post‐thaw motilities and original motility return percentages were assessed on a random, individual‐sample basis. After the initial evaluations, samples from two boars were recollected and frozen using the UFT for breeding purposes. Four sows were bred with the UFT frozen semen to confirm fertility capability. When assessing the individual UFT techniques, all of six UFT techniques had improved post‐thaw motilities. However, treatments F (μ = 29%, return μ = 37%) and J (μ = 27%, return μ = 34%) showed the highest statistical improvement for post‐thaw (p < 0.05) and original motility percent returns (p < 0.05) when compared with either the control cryo‐tube (μ = 15%, return μ = 19%) or straw groups (μ = 12%, return μ = 16%). The UFT semen had a 50% conception rate, with an average of seven piglets from the sows that farrowed. Our preliminary data suggest a higher motility return with a slower pre‐freeze phase below the freezing point before the acceleration to liquid nitrogen temperatures. The preliminary data suggest that the UFT could be utilized as a potential cryopreservation option for boar semen.
Effects of Long‐term Growth Hormone‐releasing Factor Administration on Plasma Growth Hormone, Luteinizing Hormone and Progesterone Profiles in Growing Female Buffaloes (Bubalus bubalis)
Authors: Mondal M , Prakash BS 
Published: September 2004

ContentsTo investigate the effects of long‐term growth hormone‐releasing factor (GRF) administration on plasma growth hormone (GH), LH and progesterone and body weight gain in growing buffalo calves, 12 female Murrah buffaloes within the age group of 6–8 months of age were divided into two groups (treatment and control groups) of six each in such a way so that average body weights between the groups did not differ (p > 0.05). Control buffaloes were not given any hormonal treatment and treatment group buffaloes were treated with synthetic bovine GRF [bGRF (1–44)‐NH2] at the rate of 10 μg/100 kg body weight intravenously at an interval of 15 days from week 6 (5‐week pre‐treatment period) till 18 injections were completed (week 6–42 treatment period) and thereafter, effect of exogenous GRF were observed for 10‐week post‐treatment period. Jugular blood samples were drawn twice a week at 3–4‐day intervals for plasma GH, LH and progesterone quantification. Body weight of all animals was recorded twice a week. During pre‐treatment period, mean plasma GH, LH and progesterone did not differ (p > 0.05) between the groups. But during treatment as well as post‐treatment period, mean plasma GH levels were found to be significantly (p < 0.01) higher in treatment than control group of buffaloes. Administration of GRF for longer term sustained a higher level of plasma GH even after cessation of treatment. GRF‐treated buffaloes attained higher (p < 0.01) body weight than the controls. Repeated GRF administration for long‐term significantly (p < 0.01) increased plasma LH and progesterone. In conclusion, repeated long‐term exogenous GRF administration induces and even enhances GH release without any sign of refractoriness. GRF may, therefore, be used to induce daily GH release without loss of responsiveness over an extended period of time in young growing female buffaloes and it may assist these animals to grow faster.
Prostaglandins F2α and E2 Secretion by Porcine Epithelial and Stromal Endometrial Cells on Different Days of the Oestrous Cycle
Authors: Blitek A , Ziecik AJ 
Published: September 2004

ContentsThe endometrial tissue of the uterus plays a key role in reproduction and is a source of hormones and factors responsible for the proper physiological function of reproductive tract during the oestrous cycle and pregnancy. In this study, we investigated the pattern of PGF2α and PGE2 secretion from cultured porcine endometrial cells at different days of the oestrous cycle. Epithelial and stromal cells were isolated by differential enzymatic digestion on days 6–8, 10–12 and 14–16. After attachment cells were incubated for 3 and 24 h to estimate PGF2α and PGE2 output. The purity of culture was 85–90% for epithelial and 95–98% for stromal cells as determined by immunofluorescent staining. Release of PGF2α and PGE2 was affected by cell type, days of the oestrous cycle and the time of incubation. After 3 h of incubation epithelial cells secreted more PGF2α than PGE2 during all studied periods of the oestrous cycle (p < 0.01 and p < 0.001, respectively), whereas stromal cells released more PGE2 (p < 0.01) on days 10–12 and 14–16. Longer incubation of stromal cells revealed that PGF2α output tended to overcome PGE2 on days 10–16. The lowest secretion of prostaglandins was observed on days 6–8 in both cell types. The highest secretion of PGF2α from epithelium was measured on days 10–12 after 24 h of incubation when compared with other days studied (p < 0.001). In stromal cells, PGE2 output increased on consecutive days studied (p < 0.001) after 3 h of incubation. The differential properties of endometrial cell types seem to play an important role in the profile of PGF2α and PGE2 release before and during luteolysis. Described endometrial cells culture might serve as the model for further studies on the hormonal regulation of prostaglandin production in the pig.
In Vivo Embryo Recovery Rate by Laparoscopic Technique from Rabbit Does Selected for Growth Rate
Authors: Mehaisen GMK , Vicente JS , Lavara R 
Published: September 2004

ContentsRabbit does from R line selected for growth rate present a low reproductive performance and this study aimed to evaluate both the recovery efficacy and viability of recovered embryos after vitrification and the reproductive performance of donor does subjected to in vivo recovery. Does were divided into three groups: 28 does without in vivo recovery (control), 25 does in which in vivo recovery was started in the nulliparous state (group 1) and 30 does with at least one litter before in vivo recovery (group 2). Does were superovulated with a single subcutaneous injection of 50 IU of equine chorionic gonadotropin (eCG) per female, and were then artificially inseminated 60 h later and immediately administered an intravenous dose of 75 IU of human chorionic gonadotropin (hCG) per female. Does from group 1 and 2 were recovered in vivo 76–80 h post‐insemination by repeated laparoscopies at one to four times and permitted one or two parturitions between recoveries [in vivo (IV) recovery]. At the end of the experiment, about 16 does of all groups were recovered post‐mortem (PM recovery). All normal embryos were vitrified, devitrified and then cultivated in vitro to evaluate the viability after thawing. A significant increase in the ovulation rate was found in does recovered PM than in those recovered IV in the nulliparous state. However, no significant differences were observed in the recovery rate, the donor rate, the number of normal embryos recovered with at least one normal embryo per doe and the viability after thawing between the PM and IV groups. A significant decrease in the fertility rate, total born, live born and weaned kids was found for does from group 1 in comparison with does from group 2. Results support the use of repeated laparoscopy to increase the number of recovered embryos per donor doe especially in such R line does, if they are permitted to produce at least one litter before the beginning of in vivo recovery.
Effects of Retinol on the in vitro Development of Bos Indicus Embryos to Blastocysts in Two Different Culture Systems
Authors: Lima PF , Oliveira MAL , Gonçalves PBD , Montagner MM , Reichenbach H‐D , Weppert M , Neto CCC , Pina VMR , Santos MHB 
Published: September 2004

ContentsThe objective of this study was to evaluate the effect of retinol on the in vitro development of early embryos of cultured Bos indicus (Expt 1) to the blastocyst stage in medium simplex of optimization (KSOM) or sintetic fluid of oviduct (SOF) or co‐cultured (Expt 2) with an oviduct cell monolayer (OCM) in KSOM or SOF. A total of 3149 cumulus–oocyte complexes obtained by aspirating follicles (2–5 mm diameter) from ovaries of slaughtered animals were selected for IVM and incubated in TCM 199 supplemented with 25 mM HEPES at 39°C in air with 5% CO2 and maximum humidity for 24 h. In vitro fertilization (IVF) was performed in modified defined medium (mDM) medium. Eighteen hours after IVF, cumulus cells were removed and presumptive zygotes were randomly allocated to the experimental groups. Zygotes cultured (Expt 1) in KSOM + retinol, KSOM, SOF + retinol and SOF were incubated in maximum humidity at 39°C, 5% CO2, 5% O2 and 90% N2. Zygotes co‐cultured (Expt 2) in KSOM + retinol + OCM, KSOM + OCM, SOF + retinol + OCM and SOF + OCM were incubated at 39°C, 5% CO2. In both experiments media were partially changed 48 h after IVF and unfertilized ova were removed. Afterwards embryos were kept in culture or co‐culture for further 9 days. In Expt 1, blastocyst rates (day 7) were 14.6% (KSOM + retinol), 15.8% (KSOM), 16.4% (SOF + retinol) and 15.9% (SOF). In Expt 2, the blastocyst rates (day 7) were 25.4% (KSOM + retinol + OCM) 14.2% (KSOM + OCM), 24.3% (SOF + retinol + OCM) and 15.9% (SOF + OCM). The same influence profile of retinol was observed in the formation of the expanded (day 9) and hatched (day 11) blastocysts. The results obtained in Expt 2 demonstrated that the addition of 0.28 μg/ml retinol to the embryo culture media used in this study had a significant (p < 0.05) positive effect on bovine early embryonic development, under the conditions tested, and can be used to enhance in vitro embryo production.
Immunohistochemical Studies on Oestrogen Receptor Alpha (ERα) and the Proliferative Marker Ki‐67 in the Sow Uterus at Oestrus and Early Pregnancy
Authors: Sukjumlong S , Persson E , Kaeoket K , Dalin A‐M 
Published: September 2004

ContentsOestrogen receptor alpha (ERα), the main subtype in the uterus, is involved in the regulation of uterine growth/proliferation. A relationship between ERα and proliferative activity has been shown in the cyclic sow uterus, but to our knowledge, no study has been carried out on early pregnant sows. Therefore, by means of immunohistochemistry and use of mouse monoclonal antibodies to ERα and a proliferative marker, Ki‐67, the localization of these proteins was investigated in the sow uterus during early pregnancy. Eighteen crossbred multiparous sows were artificially inseminated once at 20–15 h before expected ovulation. After artificial insemination (AI), they were slaughtered at five different times: at oestrus, 5–6 h after AI (n = 4), 20–25 h after ovulation (n =4), 70 h after ovulation (n = 4), on day 11 (the first day of standing oestrus = day 1, n = 3) and on day 19 (n = 3). Immediately after slaughter, uterine samples were collected at the mesometrial side of the uteri, fixed in 10% formaldehyde and embedded in paraffin. Immunohistochemistry was performed by using mouse monoclonal antibodies to ERα (C‐311) and Ki‐67 (MM1). All sows slaughtered after ovulation were pregnant. In general, positive immunostaining for ERα and Ki‐67 was found in the nuclei. Variations in staining intensity and proportion of positive nuclei were observed in different uterine compartments and stages of early pregnancy. The highest level of ERα presence in the surface epithelium and myometrium was found at oestrus (5–6 h after AI), and low levels of ERα in these compartments were observed as early as 20–25 h after ovulation. In the glandular epithelia, presence of ERα was highest at 70 h after ovulation. The largest number of ERα‐positive cells in the stroma was observed at oestrus and early after ovulation. Low proliferation was observed, and with no significant difference in tissue compartments except in the glandular epithelium. High proliferative activity in the glandular epithelium at 70 h after ovulation indicated involvement in preparation for secretory activity and growth during pregnancy establishment. Significant positive correlation was found between the number of ERα‐positive cells in the stroma and Ki‐67‐positive cells in the surface epithelium. In conclusion, the present study showed differences in immunolocalization of ERα and the proliferative marker Ki‐67 in different tissue compartments of the sow uterus at oestrus and early pregnancy. In some uterine compartments, the patterns of ERα and Ki‐67 immunostaining seemed to be influenced by insemination and the presence of embryos, in addition to the effects of steroid hormones.
Comparative Effects of Autologous and Homologous Seminal Plasma on the Viability of Largely Extended Boar Spermatozoa
Authors: Caballero I , Vazquez JM , Centurión F , Rodríguez‐Martinez H , Parrilla I , Roca J , Cuello C , Martinez EA 
Published: September 2004

ContentsSperm handling, associated to artificial reproduction technologies (ART) such as in vitro fertilization (IVF) or the use of flow cytometry for cell analysis or sorting imposes volumetric extension of the sperm suspension and decreases sperm viability, presumably because of the removal of seminal plasma (SP) components. This study evaluated whether a 10% v/v of autologous SP (retrieved from the same donor boar) or homologous SP (e.g. from any of the four fertile boars included, other than the one providing the spermatozoa) would differently affect the viability of boar spermatozoa subjected to large extension in a simple saline medium [phosphate‐buffered saline and 0.1% ethylenediaminetetraacetic acid (EDTA), PBSm] to a concentration of 0.3 × 106 spermatozoa/ml and incubated for 2 h at 30°C. Sperm viability was monitored as membrane integrity [using the fluorophore carboxyfluorescein diacetate (C‐FDA) and propidium iodide (PI)], mitochondrial function (using the fluorophore R‐123) and motility characteristics [using Computer Assisted Sperm Analysis (CASA)]. Substraction of the SP and extension followed by incubation in PBSm significantly (p < 0.05) decreased sperm viability, which could be restored by addition of autologous SP. Furthermore, exposure of the extended spermatozoa to homologous SP (from any other individual boar) significantly (p < 0.05) varied with the source of the sire; some boars exerting beneficial effects (even surpassing the effects of the autologous SP; p < 0.05) while at least one boar negatively (p < 0.05) influencing the viability of the incubated spermatozoa. It is concluded that SP should be present when incubating highly extended spermatozoa. As a result of the obvious differences among boars, it would be advantageous to examine the ability of SP to maintain sperm viability prior to the use of SP pools during sperm handling in vitro.
Life history traits and coexistence of an amphidiploid,Drosera tokaiensis, and its parental species,D. rotundifoliaandD. spatulata(Droseraceae)
Authors: NAKANO MARIKO , KINOSHITA EIICHIRO , UEDA KUNIHIKO 
Published: September 2004

AbstractWe compared the life history traits of an amphidiploid species,Drosera tokaiensis(Komiya & C. Shibata) T. Nakamura & Ueda, with those of the parental species, a diploidDrosera rotundifoliaL and a tetraploidDrosera spatulataLabill. to characterize them and clarify the conditions for coexistence. The ranges of the parental species are quite different, but overlap in Japan. The amphidiploid and the parents grow together in some natural habitats. Observations and experiments on reproductive properties were carried out in a glasshouse and a laboratory. Seeds ofD. rotundifoliawere dormant, whereas those ofD. spatulatawere not. InD. tokaiensis, the dormant/non‐dormant seed ratio varied from site to site.Drosera rotundifoliahas such life history traits as concentrated flowering and seed dormancy, which are relevant to habitats with short growing seasons and a severe winter.Drosera spatulatahas such traits as a prolonged duration of flowering and non‐dormancy, relevant to habitats with long growing seasons and a mild winter.Drosera tokaiensispossesses life history traits of the parental species to various degrees, but exhibits no extreme traits. It is suggested that separation of flowering time and autogamy allow the amphidiploid to coexist with the parental species.
Reproductive alternatives to insect pollination in four species of Thalictrum (Ranunculaceae)
Authors: STEVEN JANET C. , WALLER DONALD M. 
Published: September 2004

AbstractAlthough insect pollination is ancestral in the angiosperms, selection has favored wind pollination and self‐fertilization in many lineages. The evolution of clonal growth may have also decreased dependence on insect pollinators. We investigate transitions away from insect pollination in the genus Thalictrum (Ranunculaceae) among four species that vary in pollination syndrome. Thalictrum sparsiflorum is insect pollinated and self‐fertilization may also provide reproductive assurance. Thalictrum alpinum is clonal, has a floral morphology associated with wind pollination and is self‐compatible. Thalictrum fendleri is a wind‐pollinated and dioecious species that sets few fruits naturally and invests little in sexual reproduction, possibly due to a trade‐off with clonal growth. Thalictrum dioicum is also wind‐pollinated and dioecious, but does not grow clonally at our sites and has a higher investment in sexual reproduction than T. fendleri. The pollen : ovule ratio is largest in wind‐pollinated species, but varies considerably among them, possibly reflecting differences in pollination efficiency and/or incidental insect pollination. None of the species appear pollen limited in the study populations, suggesting that factors other than pollen receipt limit female fertility at these sites.
Germination and seedling survivorship characteristics of hybrids between native and alien species of dandelion (Taraxacum)
Authors: HOYA AKIHIKO , SHIBAIKE HIROYUKI , MORITA TATSUYOSHI , ITO MOTOMI 
Published: September 2004

AbstractSpontaneous hybrids between native and invasive species ofTaraxacumwere studied by means of seed germination characteristics at 4–34°C and seedling survivorship at 6–36°C. At high (28–34°C) and low (4°C) temperatures, the germination percentage was low in 4X hybrids andT. platycarpum,whereas it was high in 3X hybrids, MP (male partheno genesis) hybrids andT. officinale.When the seeds that did not germinate at high or low temperatures were incubated at 16°C for 10 days, most of the 4X hybrid andT. platycarpumseeds germinated. It was suggested that the germination of 4X hybrid andT. platycarpumseeds was suppressed at high and low temperatures. At 6–24°C, seedlings of all lineages that includedT. platycarpum,T. officinaleand three type hybrids exhibited a high survivorship of approximately 80–100% and no significant difference was observed between lineages. In contrast, at high temperatures survivorship of 4X hybrid seedlings was significantly higher than that of other lineages, approximately 90% at 31°C and 80% at 36°C. These results suggested that if 4X hybrid competes withT. officinalein hot areas during the seedling period, 4X hybrid would have the advantage overT. officinale, whose seedlings could not survive under high temperatures.