bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some Aspects of Reproductive Performance in Arabian Mares in Egypt
Authors: El‐Wishy A. B. , El‐Sayed M.A.I. , Seida A.A. , Ghoneim I.M. , Serur B.H. 
Published: October 2007

ContentsThe reproductive records of 256 Arabian mares between 1922 and 1982 inclusive were analysed. The length of gestation (mean 332.1 ± 3.3 days, range 300–371 days) was significantly influenced by month of foaling (p < 0.01), but not by sequence or sex of the foal. The average interval to foal heat was 7.6 ± 0.1 days. Most of the heat periods (76.3%) occurred between 6 and 8 days after foaling. Foaling rate was significantly higher (p < 0.05) for mares bred on days 9–11 (44%) than those bred on days 5–8 (33%) post‐foaling. Oestrus occurred throughout the year but was less frequent in summer than in spring and autumn (p < 0.05). Only 40% of the interservice intervals fell within the normal range of 13–34 days (mean 24 days).Inhalt: Einige Gesichtspunkte zur Reproduktionsleistung von Araber Stuten in ÅgyptenDie Reproduktionsdaten von 256 Araber Stuten wurden für die Zeit von 1922 bis 1982 analysiert. Die Trächtigkeitsdauer (x = 332,1 ± 3,3 Tage) wurde deutlich vom Monat, nicht aber von deren Sequenz und dem Geschlecht der Fohlen beeinftuβt. Im Mittel trat die Fohlenrosse ab Tag 76 ±0,1 in Erscheinung. Die Abfohlrate war signifikant höher (p < 0.05) für Stuten, die zwischen Tag 9 und 11 gedeckt wurden (44%) im vergleich zu denen, die zwischen Tag 5 und 8 belegt wurden (33%). Rosseerscheinungen ganzjährig beobachtet, allerdings war die Frequenz im Sommer geringer als im Frühling und Herbst (p < 0,051. Nur 40% der Zwischenbehandlungsperiode lagen innerhalb eines normalen Gröβenbereiches von 13 bis 34 Tagen (x = 24 Tage).
Artificial Insemination with Frozen Semen in Ewes at Different Times of the Breeding Season
Authors: Berg K. Andersen , Aamdal J. 
Published: October 2007

Contents: Totally 13575 ewes of two different breeds, Dala and Spel, were inseminated with semen, frozen in straws and thawed at 70°C for 8 sec. An insemination dose of 0.2 ml containing approx. 150 × 106 spermatozoa with at least 45 to 50% progressive motility was imerted 5 to 12 mm into the cervix. The insemination was performed once between 12 and 30 h after the onset of heat. The NR rate of the Dala ewes increased significantly during the season. The NR rate of the ewes inseminated before 15. November was 44.3%, from 15. to 20. November 52.2%. from 20. to 25. November 55.3% and from 25. November and later 61.4%. The corresponding values for the ewes of the Spel breed were 57.3, 58.7, 61.5 and 71.0% respectively, and only the difference between the two last values was statistically significant. The difference between the fertility of the two breeds was significant within each of the periods.
Isolation of Y Chromosome‐specific Sequences and their Use in Embryo Sexing*
Authors: Miller J.R. 
Published: October 2007

Contents: Y chromosome‐specific sequences derived to date from cattle, sheep and pigs are described. The methods used to isolate these sequences and possible future approaches are discussed. Three different techniques of sex determination are described: in situ hybridisation, Southern/Dot blotting and PCR based assays. All three methods utilise Y chromosome‐specific sequences. Necessary controls and precautions for PCR mediated assays are discussed.
Multilocus Genetic Typing of Bovine Single Cells by Multiplex Polymerase Chain Reaction *
Authors: Schwerin M. , Warnat G. , Giehm D. , Wolf H. , Thomsen P.D. 
Published: October 2007

Contents: A method of simultaneous amplification at three different loci (Y‐specific DNA, kappa‐casein gene, growth hormone gene) in cattle is presented. The use of this procedure for genetic typing on bovine crude DNA samples from less than ten diploid cells is shown. The application of this method for embryo genotyping and animal breeding is discussed.
Culture of frozen/thawed Bovine Demi‐Embryos with Bovine Oviduct Epithelial Cells*
Authors: Schmidt M. , Avery B. , Smith S. 
Published: October 2007

Contents: A method for in vitro culture of splitted frozen/thawed bovine embryos is described. These demi‐embryos are of a low viability, but they survive the treatments, which lead to the final cultivation. The culture system gave a development of 41%of demi‐embryos and 75 % of the whole embryos, and it is concluded, that this system is usable to culture demi‐embryos.
Effects of Dilution Rate on the Motility and Acrosome Morphology of Boar Spermatozoa Stored at 15 °C
Authors: Marcos C. Perez , Sanchez R. , Palacio M. , Pursel V.G. , Garcia T. Perez , Rille S. Martin 
Published: October 2007

Contents: The objective of this investigation was to establish the optimal extent of dilution for storage of boar spermatozoa at 15°C in Kiev diluent. The dilution titers used for the sperm‐rich fraction of ejaculates from 8 boars ranged from 1:2 to 1:50. Seminal doses were stored for 10 days. Motility and acrosome morphology were evaluated after 1, 3, 5, 7, and 10 days of storage. The percentages of motile spermatozoa after 24 and 72 hours of storage were significantly higher for dilution rates between 1:7 and 1:11 than for dilution rates lower than 1:7 or higher than 1:11 (p < 0.05). The percentages of spermatozoa with normal acrosomes after 24, 72, and 120 hours of storage were significantly higher for dilution rates between 1:8 and 1:11 than for dilution rates lower than 1:8 or higher than 1:11 (p < 0.01).
Effects of the Sire and District of A1 on Cow Fertility
Authors: Humblot P. , Decoux G. , Dhorne T. 
Published: October 2007

Contents: Insemination results per bull and district of AI (or technician) were analysed in a 5 year study. Return Rates (RR) were registered between Oct. 1976 and Sept. 1981. Data included 856 850 first AI made by 56 technicians. Depending on years, AI were made with the semen of 81 to 103 bulls of 5 breeds. Only bulls which performed at least 500 AI's per year were taken into account. A first analysis made with the data of 14 bulls represented during the 5 years show that: 1) the breed, the bull within breed and district of AI (or technician) were the most important factors influencing RR. RR were less affected by other factors such as the size of the herd or the year. 2) results given for successive RR were nearly identical from RR24 to RR90. 3) the effect of breed, bull and district of AI were less important on the variable illustrating more specificially late return in oestrus (RR25–300). Yearly analysis involving larger number of bulls gave very similar results to the 5 year study. Variability due to the district of AI (or technician) and to the bull were of the same magnitude. Maximum differences between bulls or districts varied from 10% (RR24) to 20% (RR90). As strong relationships between bull and district of AI or technician were found, complementary analyses from the 1978 set of data were made to investigate how the variability due to the district of AI could introduce bias when estimating bull's RR. Comparisons between models were made on the basis of correlations between a reference model including a district effect and reduced models. For RR24 and RR90 correlations between solutions were always higher than 0.97. This show that if sufficient number of AI's per bull are performed no major bias is introduced and the district of AI or technician is neglectable when evaluating bull's RR.
Studies on Some Aspects of Neutrophil Functions and Uterine Defenses in Cows during the Estrous Cycle
Authors: Hussain A.M. , Daniel R.C.W. 
Published: October 2007

Contents: Some aspects of the bovine uterine defense mechanisms were evaluated over two successive estrous cycles in five adult nonpregnant Friesian cows. Uterine flushings and blood samples were taken from each cow during the estrus and diestrus phases of each estrous cycle. A significant higher percentage of Candida albicans (C. albicans) were phagocytosed (P < 0.01) and killed (P < 0.05) by blood neutrophils during estrus than during diestrus. N‐acetyl‐β‐D‐glucosaminidase activity of uterine flushings, blood neutrophil alkaline phosphatase activity scores, and serum progesterone concentrations during diestrus increased significantly (P < 0.01) compared to those at estrus. Mean total blood leucocyte and monocyte counts increased significantly (P < 0.05) during estrus compared to diestrus. It is concluded, that the different hormonal status has at each stage of the estrous cycle a definite effect on uterine resistance against bacterial infection and a fall in serum progesterone concentrations is associated with an increased ability of blood neutrophils to phagocytose and kill C. albicans.
Chemical and Biochemical Changes in the Uterine Wall During the Postpartum Period in Cows
Authors: Doležel R. , Kudláč E. 
Published: October 2007

Contents Three pluriparous cows (crossbreeds of Czech Red and White and Holstein‐Friesian breeds) were slaughtered in 5 day intervals from parturition to day 35 post partum (pp). Selected organic and inorganic substances as well as enzyme activities were measured by spectrophotometer separately in the intercaruncular endometrium and in the myometrium of the previously pregnant uterine horn, the nonpregnant uterine horn and the uterine body. The content of P significantly (p < 0.05) increased from day 0 (3.77 and 3.38 mg·g‐1) to day 15 pp (8.67 and 7.17 mg·g‐1) in the endometrium as well as in the myometrium of the previously pregnant uterine horn. The content of chlorides continually (p < 0.05) decreased in all parts of the uterine wall from day 0 to day 35 pp. K, Na, Ca, Mg, dry matter, glycogen, ALP, ACP and LD varied from parturition to day 35 pp in a nonsignificant manner. Results suggest that the principal part of the physiological change in the uterine wall during postpartal involution in cows are finished until day 25 after parturition.Inhalt: Chemische und biochemische Veränderungen in der Gebärmutterwand der Kühe während der NachgeburtsperiodeIn 5tagigen Intervallen von der Geburt bis 35. Tag post partum wurden immer 3 Kühe (böhmische rotbunte Rasse mit Holstein‐Frisian gekreuzt) geschlachtet. In dem inter‐karunkularen Endometrium und Myometrium des früher trächtigen und unträchtigen Gebärmutterhorns sowie im Gebärmutterkörper wurden spektrophotometrisch Gehalte von organischen und anorganischen Stoffen und Aktivität von manchen Enzymen fest‐gestellt. Gehalt von P sank signifikant von 0 Tag (3,77 und 3,38 mg · g‐1) zum 15. Tag post partum (8,67 und 7,17 mg · g‐1) im Endometrium und Myometrium des früher trächtigen Gebärmutterhornes. Gehalt von Chloriden hat sich kontinuierlich in allen untersuchten Teilen der Gebärmutterwand von 0 Tag bis 35. Tag post partum herabgesetzt. Gehalte von K, Na, Ca, Mg, Trockensubstanz, Glykogen und Aktivität von Enzymen ALP, ACP und LD haben unregelmäßig von der Geburt bis zum 35. Tag post partum geschwankt.Die Ergebnisse verweisen darauf daß der Hauptteil von den Veränderungen in der Gebärmutterwand der Kühe in der Nachgeburtsperiode bis 25. Tag post partum beendet wird.
Failure to Remove Bovine Diarrhea Virus (BVDV) from Bull Semen by Swim up and other Separatory Sperm Techniques Associated with in vitro Fertilization
Authors: Bielanski A. , Dubuc C. , Hare W.C.D. 
Published: October 2007

Contents:Semen samples, collected from bulls pesistently infected with bovine viral diarrhea virus (BVDV) and containing BVDV (titer 105 ‐ 106TCID50/ml), were subjected to sperm separation procedures (washing, swim up, Percoll gradient, glass wool filtration, glass beads filtration) that are commonly used prior to in vitro fertilization (IVF) to determine if these procedures would yield spermatozoa free from BVDV. The final sperm pellets from frozen and fresh ejaculates were tested for the presence of BVDV by the immunoperoxidase technique; all tests were positive for BVDV in the range of 103 ‐ 104TCID50/ml). The study shows that when semen containing BVDV at the level of 105 ‐ 106TCID50/ml) is used for IVF, the virus is not completely removed by any of the simple physical methods commonly used to prepare sperm for IVF. Inhalt: Feldversuch das bovine Diarrhoe Virus (BVDV) aus Bullensperma durch Swim up oder andere Trennverfahren in Verbindung mit der In vitro Fertilisation zu entfernen Spermaproben, die von Bullen gewonnen wurden, welche dauerhaft mit dem Virus der bovinen Virus‐Diarrhoe (BVDV) infiziert waren und einen Titer zwischen 105 ‐ 106TCID50/ml enthielten, wurden verschiedenen Trennverfahren unterzogen (Waschen, swim up, Percoll gradient, Glaswollenfiltration, Glaskugelfiltration). Diese Verfahren werden üblicherweise für die Vorbereitung zur In vitro Befruchtung verwendet, und es sollte geprüft werden, ob diese Verfahren auch das Sperma von dem BVD‐Virus befreien können. Das endgültige Spermapellet von gefrorenen/aufgetauten und frischen Ejakulaten wurde in Gegenwart des BVD‐Virus und mit Hilfe der immunoperoxidase Technik getestet. Alle Testergebnisse waren positiv für BVD‐Virus in einem Bereich von 103 ‐ 104 TCID50/ml. Die Studie zeigt, daß Sperma, wenn es 105‐106TCID50/ml des Virus enhält, nicht vollständig mit den für die IVF üblichen, einfachen physikalischen Methoden von dem Virus befeit werden kann.
Cumulus Oophorus Expansion of Bovine Oocytes Cultured in vitro: A SEM and TEM Study
Authors: Laurincík J. , Pivko J. , Kroslák P. 
Published: October 2007

Content:Bovine cumulus‐oocyte complexes (COCs) were aspirated from antral follicles (3–6 mm in diameter). COCs with a compact multilayered cumulus investment were cultured for 9, 13 and 24 hours, respectively, and processed for scanning or transmission electron microscopy after different periods of culture including a 0 hour control group. In all 0 hour control COCs initial formation of cumulus cell projections, blebs and microvilli were observed. The start of cumulus‐oocyte disconnection in cattle was observed after 9 hours of in vitro culture. These connections were almost completely discrupted after 13 hours, when a continuous production of extracellular matrix was observed. The full expansion of corona radiata cells was not observed even after 24 hours. Some cumulus oophorus cells were bound together with junctions of the zonula adherens type after 24 hours when extracellular matrix was found only in deeper layers. The full expansion of corona radiata cells was not the prerequisite for disconnection of cumulus‐oocyte complex. Inhalt: Kumulus oophorus Expansion von in vitro kultivierten Rinderoozyten: Eine SEM und TEM Untersuchung Kumulus‐Oozyten‐Komplexe (COC) von Rindern wurden aus antralen Follikeln aspiriert (Durchmesser 3–6 mm). COC's mit kompakten mehrschichtigen Kumulus wurden für 9, 13 und 24 Stunden kultiviert und für die Scanner‐ oder Transmissionselektronenmikroskopie vorbereitet. Verschiedene Kulturzeiten incl. einer 0‐Stundengruppe als Kontrolle wurden untersucht.In allen Kontroll COC's wurden beginnende Formationen yon Kumuluszellprojektionen, Bläschen und Mikrovilli beobachtet. Nach 9‐stündiger in vitro Kultur begann die Lösung zwischen Kumulus und Oozyte. Die Verbindungen waren nach 13 Stunden vollständig unterbrochen, wobei eine kontinuierliche Produktion extrazellulärer Matrix beobachtet wurde. Eine vollständige Expansion der Corona radiata Zellen wurde auch nicht nach 24 Stunden beobachtet. Nach 24 Stunden waren einige Cumulus Oophorus Zellen über Verbindungen des Zonula adherens Typs verknüpft, wobei extrazelluläre Matrix nur in den tieferen Zellschichten gefunden wurde. Eine vollständige Kumulusexpansion ist keine Voraussetzung für die Auflösung des Kumulus‐Oozyten‐Komplexes.
Nutrition and Early Embryonic Development
Authors: Boland MP , O'Callaghan D 
Published: October 2007

SummaryThe ‐purpose of this paper is to examine mainly the role of energy intake on early embryo development. It has been shown that reduced energy intake can alter follicle growth patterns whereby follicle size is reduced and animals will have more waves of follicle growth throughout the cycle. In addition several studies have shown that high concentrate intake prior to or during superovulation will lead to reduced follicular growth and poorer embryo quality in beef heifers. In addition embryos recovered from animals on lower intakes have a better capacity to develop in short term culture in vitro. With a model using ovum pickup and in vitro maturation, fertilization and culture, it has not been possible to demonstrate clearly if the nutritional damage occurs prior to or after fertilization.
The Modulation of Gonadotrophs Hormone Action on the Ovary by Paracrine and Autocrine Factors
Authors: Campbell BK 
Published: October 2007

AbstractIt has been hypothesized that the physiological basis of follicle selection is the differential expression of factors, that modulate the action of gonadotrophins on follicular cells, at key points during the process of follicle development. The aim of this research was to test this hypothesis by identifying factors that can enhance or attenuate the action of the gonadotrophins in stimulating follicle development using both in vivo and in vitro models.Experiments in vivo utilized sheep with an ovarian autotransplant to allow intra‐arterial infusion of putative local factors and exposure of the ovary to high local concentrations. Experiments in vitro utilized physiological serum‐free cell culture systems for both granulosa and theca cells that allow gonadotrophin‐induced differentiation in vitro. The putative local factors tested included insulin‐like growth factor‐I (IGF‐I LR3 analogue), transforming growth factor a (TGFα) or epidermal growth factor (EGF) and in‐hibin A.IGF‐I stimulated both cellular proliferation and hormone production by both granulosa and theca cells in vitro and similarly stimulated ovarian follicle development and ovarian androgen and oestradiol secretion in vivo. Both TGFα and EGF stimulated granulosa and thecal cell proliferation in vitro in a dose responsive manner and concomitantly inhibited hormone production whereas intra‐arterial infusion of TGFαin vivo resulted in induction of atresia in large antral follicles and an acute fall in ovarian hormone secretion. Inhibin A in vitro augmented gonadotrophin stimulated androgen and oestradiol production by thecal and granulosa cells respectively, but had no effect on cell number. Paradoxically, intra‐arterial infusion of inhibin A resulted in an acute depression in ovarian steroid secretion. This depression, however, was also associated with an acute depression in circulating FSH concentrations. In conclusion, these data provide strong support for the hypothesis that factors can modulate the action of gonadotrophins on follicular cells to augment (IGF‐I, inhibin A) or inhibit (TGFα/EGF) granulosa and thecal cell differentiation. The challenge for the future in this area of research is to understand how these factors interact to enable one follicle to be selected from an ovulatory cohort.
Oxytocin Secretion and Management of Parturition in the Pig
Authors: Gilbert CL 
Published: October 2007

AbstractThis paper will examine the augmentation of oxytocin (OT) secretion in the final day before parturition in the pig, and review the key endocrine systems of influence. Recent experiments have shown that increases in plasma OT above baseline secretion were not seen until 7 hours prior to the birth of the first piglet. Progesterone release begins to decline some days before birth and is unlikely to provide such acute control of OT release immediately before birth. The involvement of relaxin is complex but it is possible that the prepartum relaxin surge, which ends close to the OT rise, attenuates OT secretion to prevent excessive myometrial activity until cervical softening has occurred. Increasing myometrial electromyographic activity appears to be seen as relaxin concentrations decline and OT increase. Endogenous opioid peptides within the hypothalamus exert a profound influence upon OT secretion during birth, and some effects are also seen prepartum. It has been proposed that this system may allow parturition to be interrupted or slowed in response to changes in environment. The therapeutic choice of exogenous injections of OT to control the onset time of parturition will be discussed in the light of current physiological knowledge.
The Role of Uterine and Ovarian Hormones in Luteolysis: A Comparison among Species
Authors: Silvia WJ 
Published: October 2007

AbstractLuteolytic mechanisms have evolved in mammals to improve reproductive efficiency. The hormonal interactions that control the onset and progress of luteolysis are complex. They involve endocrine and paracrine signals that link the corpus luteum, uterus and posterior pituitary gland. Current concepts concerning these interactions will be examined in the five major domestic ungulate species commonly raised in Europe and North America (cattle, sheep, goats, pigs and horses). Some of these interactions are similar across species. All five depend on prostaglandin F2αsecreted from the uterus, to induce luteolysis. Three hormones, progesterone, estradiol and oxytocin interact to regulate uterine secretion of PGF2α. Oxytocin is an acute stimulus for uterine PGF2αsecretion. Progesterone and estradiol interact to regulate uterine secretary responsiveness to oxytocin. Precisely how these hormones interact varies across species.
Useful Technique for the Study of Intracellular Calcium Fluxes in Single Porcine Granulosa Cells in Culture
Authors: Szafrañska B. , Tilton J.E. , Ary T. 
Published: October 2007

ContentsA new experimental model was applied to study calcium involvement in the mechanisms of action of the pituitary hormones on porcine granulosa cells (GC) on single cells in culture and in a time‐dependent manner. The model involved laser cytometry with calcium‐sensitive dye fluo‐3AM. This study describes pituitary hormone‐mediated changes of calcium (Ca2+) concentrations in cultured porcine GC, at the single cell level. Cells were isolated from medium sized follicles of cycling mature gilts (day 16–19 post‐oestrus) and were cultured at a concentration of 50–100 × 103 cells/Petri dish in 2 ml of enriched M199 medium for 2–3 days. Image scans were performed on individual cells that had been loaded with calcium‐sensitive dye, acetoxymethyl ester of fluo‐3 (fluo‐3 AM; 488ex/526em nm). In Experiment A (nexp = 6), cell response was measured after treatment with porcine luteinizing hormone (pLH) or prolactin (pPrl) (doses of 0, 1, 10 and 100 ng/ml in pH indicator‐free HBSS containing 2 m
m of Ca2+). In cultures treated with 1, 10 and 100 ng of pLH (Ncells = 329), increases in relative fluorescence were observed in 37.1, 80.0 and 72.9% of cells scanned, respectively. In cultures treated with similar dosages of pPrl (Ncells = 259), responses were noted in 41.8, 57.3 and 47.2% of cells scanned, respectively. In control cultures treated with medium alone (Ncells = 85) the fluorescence increases were not observed. Fluorescence intensity was increased in the hormone‐treated cells only (p < 0.05). Seven‐fold and five‐fold relative fluorescence increases were observed for cells exposed to 100 ng of pLH or 10 ng of pPrl, respectively. In Experiment B, the effects of the Ca2+ ionophore (A23187) and Ca2+ chelator (EGTA) on the changes of calcium concentrations in GC‐treated with both pLH (100 ng/ml) and pPrl (10 ng/ml) were examined. In the presence of A23187 (10 μm), fluorescence of the cells increased two‐fold (p < 0.05) within 400 s in cultures treated with combination of both pLH and pPrl. However, EGTA (2.5 m
m) completely abolished the responses of GC to both pLH and pPrl (Ncells = 168, nexp = 16) and the fluorescence decreased to levels similar to the control group (Ncells = 159, nexp = 5). The studies clearly demonstrated that intracellular free calcium changes occur in porcine GC when they are exposed to pLH or pPrl. The present study has provided a useful technique for studying the role of calcium in regulation of porcine GC by different factors at the single porcine cell level in culture and in a time‐dependent manner.