Search Results
Results 351 - 400 of 847
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Weems Y S - - 1999
Ninety-day pregnant ewes were either laparotomized, ovaries left in situ or bilaterally ovariectomized, and a jugular venous catheter and an inferior vena cava catheter via the saphenous vein were installed. Seven days later, placenta slices were collected and incubated in vitro for 4 h. Secretions of progesterone, PGE, estradiol-17beta and ...
Weems Y S - - 1999
Ewes were lutectomized and treatments were started 72 h later. Pregnant ewes were treated with vehicle; prostaglandin F2alpha (PGF2alpha); cortisol (C); trilostane (TR), a 3beta-hydroxy-steroid dehydrogenase inhibitor; PGF2alpha + C; TR + PGF2alpha; TR + C, or TR + PGF2 + C. TR, TR + PGF2alpha, TR + C, and ...
Regnault T R - - 1999
Pregnant ewes were exposed chronically to thermoneutral (TN; 20+/-2 degrees C, 30% relative humidity; n=8) or hyperthermic (HT; 40+/-2 degrees C 12 h/day, 35+/-2 degrees C 12 h/day, 30% relative humidity, n=6) environments between days 37 and 93 of pregnancy. Ewes were killed following 56 days of exposure to either ...
Dwyer C M - - 1999
The onset of maternal behaviour in sheep is controlled by levels of oestrogen and progesterone in gestation and the release of oxytocin during delivery. Factor analysis was used to investigate the relationships between maternal behaviour, offspring behaviour, and maternal ovarian hormone levels during gestation in sheep. Ewes gave birth to ...
Sewalem A - - 1999
The present study compares embryonic mortality between lines selected for different production traits, assesses the effects of inbreeding of the hen and embryo on embryonic mortality, and estimates genetic parameters of embryonic mortality. The experiment covered 10 generations of selection for increased egg number (EN), egg weight (EW), egg mass ...
Hensley, Erika L.
Experiments were conducted to determine the effects of a treatment used to dilate the cervix for transcervical AI and embryo transfer on pregnancy or fertilization rates in sheep. Experiment 1 was conducted as a 2 x 2 factorial, with the main effects of estradiol-17b (E2) and oxytocin (OT). On d ...
Osgerby J C - - 1999
Insulin-like growth factors (IGFs) are thought to be important regulators of embryonic and fetal development. The half life, distribution and action of IGFs are modulated by a family of IGF-binding proteins (IGFBP). This study investigated the pattern of IGFBP-1 expression in the ovine uterus during the oestrous cycle and early ...
Wallace J M - - 1999
The aim was to investigate whether placental growth and hence pregnancy outcome could be altered by switching adolescent dams from a high to a moderate nutrient intake, and vice-versa, at the end of the first trimester. Embryos recovered from adult ewes inseminated by a single sire were transferred in singleton ...
al-Gubory K H - - 1999
To study the role, if any, of luteal factors in the control of prolactin secretion during the last two thirds of pregnancy in the ewe, we examined: a) the effect of RU 486 administration on prolactin secretion on days 97, 112 and 131 of pregnancy in five intact ewes and ...
Roesch D M - - 1999
The suppression of plasma adrenocorticotropic hormone by very low levels of cortisol is reduced in pregnant adrenalectomized ewes, suggesting that pregnancy reduces the efficacy of the high-affinity corticosteroid receptor. This study was designed to determine the effects of pregnancy on the availability, immunoreactivity, and affinity of both corticosteroid receptors: the ...
Kutty C I - - 1999
A palpation technique using both hands was developed by the author and used for examination of internal reproductive organs, pregnancy diagnosis, and assessment of approximate stages of gestation in small ruminants. The study was conducted in 4 stages on 87 female goats and 30 slaughterhouse source ewes First, 20 doelings ...
Grilló M J - - 1999
Forty yearling Brucella-free ewes were inoculated with Brucella ovis by the conjunctival route in mid or late first pregnancy. Only a few ewes excreted B ovis during pregnancy and gave birth to stillborn lambs, but most of them excreted the organism at lambing or during lactation. One of the 11 ...
Shinozuka N - - 1999
OBJECTIVES: This study examined the effects of increased myometrial contracture frequency from 96 to 131 days' gestation on ovine fetal oxygen transport and physiologic response to acute hypoxemia. STUDY DESIGN: Ten pregnant ewes received either saline solution (control, n = 5) or long-term administration of oxytocin (600 microU. kg-1. min-1) ...
Kühholzer B - - 1999
This study was performed to investigate the developmental potential of microinjected embryos recovered from superovulated prepuberal lambs. Fifty-nine mixed-bred lambs (about 3 mo old) were superovulated either with 18 mg FSH-P with (Group FSH/+S) or without (Group FSH/-S) progestagen treatment, or with 10 mL Ovagene following progestagen treatment (Group OVA/+S). ...
Yazdi M H - - 1999
Variance and covariance components for birth weight (BWT), as a lamb trait, and litter size measured on ewes in the first, second, and third parities (LS1 through LS3) were estimated using a Bayesian application of the Gibbs sampler. Data came from Baluchi sheep born between 1966 and 1989 at the ...
Merimsky O - - 1999
Ewing's sarcoma of the pelvic bones was diagnosed in a 21-year childbearing woman, raising major medical and ethical problems. The diagnostic and therapeutic approaches during the sixth month of gestation were tailored in order to cure the patient and avoid unnecessary toxicity to the fetus. Ancillary tests included ultrasound and ...
Vos E A - - 1999
The usefulness of fecal estrone (E1) measurement as a tool for pregnancy diagnosis was investigated. Concentrations of E1 were measured in feces from pregnant and nonpregnant sows by a direct ELISA without extraction. Highly significant differences in E1 concentrations were found in feces from nonpregnant and pregnant sows (P = ...
Andres S - - 1999
The present study evaluates blood GSHPx activity in 18 sheep flocks at range, to identify those seasons with the highest risk of selenium deficiency. Samples were taken from 1108 15-day-old lambs during the two usual lambing periods in this geographical area (autumn-winter and spring-summer). The overall mean values in the ...
Ferreira G - - 1999
Institut National de Recherche Agronomique/Centre National de la Recherche Scientifique Within 4 hr after parturition, ewes learn to recognize the odor of their lamb. Whether scopolamine, a muscarinic antagonist, interferes with lamb odor retention was studied. After 4 hr of mother-young contact, ewes were separated from their lambs for 3 ...
Mitchell L M - - 1999
The objective of this study was to determine the relative importance of seasonal changes in ovulation rate, fertilization rate and embryo survival as the cause of reduced lambing rates in ewes mated in February compared with those mated in November. The study was conducted at 57 degrees N using mature ...
Al-Gubory K H - - 1999
In sheep, there have been few and conflicting data regarding the necessity of the corpus luteum (CL) for the maintenance of pregnancy. The aims of the present study were to examine the effect of luteectomy on and after Day 50 of pregnancy on maternal plasma progesterone concentrations and the progression ...
Timmerman M - - 1998
Uterine and umbilical uptakes of alanine (Ala) were measured in 10 ewes before (control) and during intravenous infusion of Ala, which increased maternal arterial Ala concentration from 115 +/- 14 to 629 +/- 78 microM (P < 0.001). In 8 of these ewes, placental Ala fluxes were traced by constant ...
Freetly H C - - 1998
Our objective for this study was to determine the pattern of nutrient flux across the portal-drained viscera (PDV) and liver in ewes with varying numbers of fetuses. Catheters were placed in the hepatic portal vein, a branch of the hepatic vein, a mesenteric vein, and the abdominal aorta of ewes. ...
McDougall J J - - 1998
The ligaments of weight-bearing joints are known to become mechanically inferior during pregnancy, and it has been postulated that this may be due to changes in tissue perfusion. Calcitonin gene-related peptide (CGRP) and epinephrine exert a tonic influence on the vasculature of the medial collateral ligament (MCL), and the present ...
Nuvor S V - - 1998
In this paper, the Eimeria oocyst output of two groups, pregnant ewes (group 1) and non-pregnant controls (group 2), which were followed from September 1993 to August 1994, is described. In both groups of animals the level of oocyst output was high during the minor rainy season. However, during the ...
Heasman L - - 1998
We investigated the influence of restricted maternal nutrition between 28 and 77 d of gestation on placental weight and appearance, and on fetal weight and conformation. Single-bearing ewes were fed either twice [i.e. controls (n = 19)] or half [i.e. nutrient-restricted (n = 28)] their energy requirements from 28 to ...
Al-Gubory K H - - 1998
Ewes of the Préalpes-du-Sud breed (n = 112) were mated with fertile rams and were used to investigate the effect of the presence of vasectomized rams during pregnancy on reproductive outcomes. Ewes in the control group (n = 56) were isolated from rams during the whole period of pregnancy, whereas ...
Carter A M - - 1998
OBJECTIVE: To calibrate a reflectance pulse oximeter developed at the Division of Perinatal Physiology, University Hospital of Zurich, for monitoring of oxygen saturations below 70%. METHODS: Oxygen saturation measured noninvasively with the reflectance pulse oximeter in fetal sheep was compared with oxygen saturation of arterial blood samples measured by a ...
Coubrough C A - - 1998
Accuracy of transrectal ultrasonographic determination of fetal sex by identifying and locating the genital tubercle was determined in 29 ewes with single fetus at 60 to 69 d post breeding. Examinations were conducted once under farm conditions utilizing a real-time diagnostic scanner equipped with a linear-array 5 MHz transducer. Definite ...
Osaer S - - 1998
The effects of Trypanosoma congolense infection and nutritional supplements on live weight changes during pregnancy, haematology traits and offspring performance were studied in 42 Djallonké ewes. A randomised block design was used to allocate ewes to four treatment combinations, of which two were on a restricted diet (L) and the ...
Vandenheede M - - 1998
The effects of an enriched environment (EE, permanent presence of a humanlike model plus colored mobile objects) during the rearing period (from birth to weaning at 3 months) were assessed on subsequent fear reactions of lambs and their mothers. Behavioral tests involved isolation, surprise effect, and the presence of a ...
Oberg K C - - 1998
The use of nonpenetrating clips to accomplish wound closure as an alternative to suture in the repair of simulated cleft lips in partially exteriorized fetuses has been described previously. In this study, the fetus is approached endoscopically, and clipped (n = 8) and sutured (n = 4) intrauterine endoscopic repairs ...
Tembely S - - 1998
A study was carried out at the International Livestock Research Institute (ILRI) Debre Berhan Research Station in Ethiopia from 1992 to 1995 to compare the peri-parturient rise (PPR) in faecal nematode egg counts (FEC) in ewes of two indigenous sheep breeds. A total of 1439 Menz and 1347 Horro ewes ...
Quinlivan J A - - 1998
OBJECTIVE: To examine the effect of single or repeated injections of maternally administered corticosteroids on fetal growth in sheep. METHODS: Forty-six date-mated singleton gestation ewes were allocated at random to one of 3 groups: a single, or repeated injections of betamethasone, or a control group which received saline. On days ...
Ramsey W S - - 1998
Suffolk and Targhee ewes (30 each) with single or twin lambs were used in four periods beginning in late gestation and continuing through weaning to evaluate breed differences in milk production, lamb BW, and DMI by ewes and lambs. In Periods 1 (late gestation) and 2 (early lactation), ewes (Period ...
Kowalski W B - - 1998
Pharmacokinetic parameters of oxytocin (OT) metabolism were determined during the last third of pregnancy and again 4-8 wk after delivery in the baboon. Animals were placed on a tether system with venous and arterial access and a continuous monitoring of uterine contractions during gestation. Two methods of determining OT pharmacokinetics ...
Buxton D - - 1998
Three groups of eight pregnant sheep were inoculated with tachyzoites of the NCl isolate of Neospora caninum at 45 (group 1), 65 (group 2) or 90 (group 3) days' gestation. A further six animals (group 4) served as controls. Fourteen of the infected ewes developed a fever, which in two ...
Osaer S - - 1998
Interactions between Trypanosoma congolense and nutritional statue were studied in 42 ewes, bred at the peak of parasitaemia after synchronisation of oestrus. As experimental design a randomised block design was used with four treatment combinations (2 x 2 factors), of which two were on restricted diet (L), the remainder on ...
Gómez M C - - 1998
More abnormal fertilization has been found in sheep oocytes after intracytoplasmic sperm injection (ICSI) than after in vitro fertilization (IVF). Although the birth of a normal lamb has been reported, the efficiency of blastocyst production is low. We therefore evaluated the cleavage, development and viability of sheep embryos obtained from ...
Husein M Q - - 1998
An experiment was conducted to determine whether factors affecting pregnancy rate out-of-season are associated more with transcervical artificial insemination (T-AI) procedures or with the reproductive state of the ewe. Twenty Finncross ewes were treated with progesterone sponges, and at sponge removal (0 h) 10 ewes were treated with eCG. Blood ...
Cook C J - - 1998
AIMS: As sex related differences in opioid-induced elevations of nociceptive thresholds have been observed in sheep, a study was undertaken to determine if puberty, oestrus, pregnancy or administration of the hormones oestrogen and testosterone had any effect on these differences. METHODS: Withdrawal latency to a nociceptive thermal source was measured ...
Scott P R - - 1998
Forty multigravid ewes with naturally-occurring ovine pregnancy toxaemia were treated with a concentrated oral dextrose and electrolyte solution administered three times daily an oral and a single subcutaneous injection of either a slow release formulation of 160mg recombinant bovine somatotropin (n = 17) or placebo injection (n = 23). A ...
Hill J R - - 1998
The results of laparoscopic insemination of 28,447 Australian Merino ewes with semen from 468 rams were used to study factors influencing pregnancy. The overall pregnancy rate was 71.7% (20,423/28,447). Pregnancy rates varied with type of progestagen implant, type and dosage of PMSG, fresh or frozen semen, wool type and number ...
Stelnicki E J - - 1998
Several animal models have been designed in the past to analyze the pathophysiology and management of craniosynostosis, very few of which were intrauterine. Those that were interuterine had problems with either a short gestation or limited availability that prevented most researchers from using them in treatment analysis. We desired to ...
James P J - - 1998
Cyclic patterns and variations among sheep in numbers of Bovicola ovis are described in Polypay and Columbia ewes that were initially infested with equal numbers of lice and penned indoors continuously for 2 years. Bovicola ovis populations were censused at 3-4-week intervals at 69 body sites on each animal. In ...
Williams A F - - 1998
This investigation aimed to ascertain whether embryo transfer was a feasible method of breaking the disease cycle caused by Chlamydia psittaci (ovis). Ten naive ewe lambs were inoculated orally with the T76 and G188 isolates of C. psittaci (ovis) in late pregnancy. Five animals which sero-converted to the complement fixation ...
Baguma-Nibasheka M - - 1998
We compared the in vitro response to oxytocin, prostaglandin (PG)E2, and PGF2alpha of myometrium and mesometrium from six ovariectomized ewes and 53 ewes at 106-145 days gestational age (dGA), including 14 ewes in spontaneous or betamethasone-induced labor. Myometrial baseline activity increased from 217+/-27 mN/cm2 of cross-sectional area (mean +/-SEM) in ...
Naimark W A - - 1998
In a developing lamb model, we have used hydrothermal isometric tension (HIT) techniques to assess collagen crosslink stability and its contribution to the mechanical properties of the pericardium. Strip samples of tissue were either: (i) heated to a 90 degrees C isotherm or (ii) heated in 5 degrees C increments ...
Gates P J - - 1998
One hundred twenty-one Swedish Landrace Finewool ewes were treated with progestagen sponges (P), teaser ram stimulation (R), or melatonin implants plus teaser ram stimulation (M) in preparation for breeding with whole rams in August. Blood progesterone analyses from ewes in the R and M groups gave no evidence of luteal ...
Freyre A - - 1997
Antibodies to Toxoplasma gondii were measured before and after pregnancy in a 1:64 dilution of sera with the direct agglutination test in 1613 ewes from 18 farms in 8 different counties of Uruguay from 1992 to 1994. The overall seroprevalence increased from 28.7% before mating to 38.5% after lambing in ...
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