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Ovine anaplasmosis: in utero transmission as it relates to stage of gestation.
1987
Zaugg J.L.
Pharmacokinetics of phenolsulfonphthalein in sheep.
1993
Danielson T.J. | Taylor W.G.
Pharmacokinetic variables of phenolsulfonphthalein (PSP) were determined in sheep after rapid IV injection and IV infusion to steady state. In Suffolk wethers, an average of < 75% of an IV administered dose was eliminated in urine, indicating that measures of systemic clearance overestimate renal clearance in this species. Furthermore, PSP elimination from plasma was more rapid in Suffolk than Rambouillet wethers and, in Suffolk ewes, systemic clearance decreased from mean +/- SD 7.8 +/- 0.3 ml/min/kg of body weight to 4.7 +/- 1.1 ml/min/kg at steady-state plasma concentration of 2.4 +/- 0.3 and 151.3 +/- 31.8 micrograms/ml, respectively. These observations indicate that, similar to that in other species, systemic clearance of PSP in sheep is concentration-dependent and that significant differences may exist between breeds.
Show more [+] Less [-]Role of an intramammary device in protection against experimentally induced staphylococcal mastitis in ewes.
1993
Penades J.R. | Albizu I. | Baselga R. | Marco J. | Barberan M. | Amorena B.
An intramammary device (IMD) was adapted for use in ewes; this device was made of abraded poly. ethylene material (1.7 mm in diameter, 47 mm long) and formed a 15-mm-diameter loop in the gland cistern. The IMD was inserted in 1 gland in each of 43 ewes. A significant (P < 0.0001) increase in milk somatic cell count (SCC) was observed in glands provided with an IMD. This increase was attributable to an increase in neutrophil numbers and was observed during the first 12 weeks after insertion. The IMD had a protective effect against experimentally induced staphylococcal mastitis (Staphylococcus aureus and S epidermidis), although different milk SCC were required for protection from each bacterial species in most ewes (10(6) and 2 X 10(5) cells/ml, respectively). Histologic studies revealed that the IMD induced local squamous metaplasia in the glandular part of the lactiferous sinus. Erythrocytes were found in milk from glands provided with an IMD throughout the studied period (35 days of the 45-day lactation) and, in some cases, blood clots were observed during the first 2 weeks of lactation. Glands with IMD also had lower milk production and quality at 30 and 32 days of lactation. Eight ewes with IMD were studied throughout a subsequent lactation. Milk from the IMD-containing glands had an increase in SCC, as in the previous lactation period; did not contain blood clots or erythrocytes; and had normal composition (similar to that in glands without the IMD).
Show more [+] Less [-]Rams sexually activated in spring by light treatment stimulate social and sexual activities in non-activated rams
2023
Palacios, Carlos | Martínez-López, Alam, A | Campos-Marmolejo, Silvia, A | Plaza, Javier | Keller, Matthieu | Chemineau, Philippe | Delgadillo, Jose, A | Abecia, José, A | Facultad de Ciencias Agrarias y Ambientales ; Partenaires INRAE | Instituto de Ciencias Nucleares, UNAM ; Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM) | Physiologie de la reproduction et des comportements [Nouzilly] (PRC) ; Institut Français du Cheval et de l'Equitation [Saumur] (IFCE)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Universidad Autónoma Agraria Antonio Narro (UAAAN) | Instituto Universitario en investigación en Ciencias Ambientales de Aragón (IUCA) ; University of Zaragoza - Universidad de Zaragoza [Zaragoza]
International audience | Twelve rams were used to confirm whether rams sexually activated in spring by light treatment increase social and sexual activities of non-treated rams in the presence of ewes. Males were divided into 2 groups: light-treated rams (group L, n = 6), which were exposed to artificial long days (16 h light) for 2 months (1 Nov-31 Dec), or non-exposed, control rams (group C, n = 6), exposed to the natural pho-toperiod. At the end of the long-day period, light-treated rams were returned to the natural photoperiod, groups isolated from each other. In mid-Feb, 3 rams from each group were put together such that 4 ex-perimental groups were created: the remaining light-treated rams (L, n = 3), the remaining control rams (C, n = 3), and the other treated (L-mixed n = 3) and non-treated (C-mixed, n = 3) rams, exposed to 30, 30, and 60 ewes, respectively, in 3 separate paddocks. To identify each ram, large (30-cm-high) numbers were painted on the sides and rump of the males with washable sheep spray paint. Behaviors were doc-umented by 4 video cameras using 6 30-minute segments from 1600 to 1800 h the following day (27 hours). C rams presented the lowest proportion of activities ( P < 0.01), and C-mixed rams exhibited pro-portions similar to L and L-mixed rams. C rams exhibited the fewest fight attempts ( P < 0.001), fighting ( P < 0.05), pushing ( P < 0.001), and sniffing another ram. The groups differed significantly ( P < 0.001) in pushing, pawing, flehmen, and attempt mounting, and C rams had the fewest interactions. In conclusion, rams exposed to 2 months of long days at late-autumn early-winter increased social and sexual activities of unexposed rams. These observations can be explained by a "ram-to-ram effect", which can enhance the endocrine activity of rams in sexual rest if they are joined with rams who have been made sexually active by a photoperiodic treatment. These findings suggest that socio-sexual interactions could be used to restrict out-of-season reproduction in this species.
Show more [+] Less [-]Oestrus synchronisation with progesterone-containing sponge and equine chorionic gonadotropin in Pirlak ewes during the non-breeding season: can Toryum improve fertility parameters?
2020
Kuru, Mushap | Boga Kuru, Buket | Sogukpinar, Osman | Cebi Sen, Cigdem | Oral, Hasan | Kirmizibayrak, Turgut
The aim of the study was to determine the effect of the vitamins, omega-3 polyunsaturated fatty acid and minerals in the supplement Toryum administered before and during oestrus synchronisation on some fertility parameters of ewes during the non-breeding season. The experimental animals were clinically healthy Pirlak ewes, 55–75 days postpartum, aged 2–4 years and weighing 40–50 kg. A sponge was inserted into the vagina for 10 d (G1, n = 30; G2, n = 30) or 14 d (G3, n = 30; G4, n = 30) for oestrus synchronisation, and on the day of removal, 400 IU equine chorionic gonadotropin was injected. Toryum soft capsules were administered individually (1 capsule/ewe p.o.) to G1 and G3 ewes seven days before the sponge was inserted and on the day it was removed. Oestrus detection was started 12 h after sponge removal. Pregnancy was diagnosed by transrectal ultrasonography on the 30ᵗʰ day after mating. The pregnancy rate was statistically different between G1 and G4 (P < 0.05). The onset of oestrus was statistically different (P < 0.001) between the 10-d groups (G1 and G2) and the 14-d groups (G3 and G4). The litter size and oestrus, conception, lambing, multiple birth, and survival rates were not significantly different between the groups (P > 0.05). Toryum administered to Pirlak ewes during progesterone-based oestrus synchronisation protocols during the non-breeding season may increase pregnancy rates. The relationship between Toryum and fertility parameters in ewes would be better understood by comprehensive studies.
Show more [+] Less [-]Monitoring vaginal electrical resistance, follicular waves, and hormonal profile during oestrous cycle in the transition period in Bangladeshi sheep
2018
Talukder, Mohammad Rafiqul Islam | Hasan, Moinul | Rosy, Tasmia Akter | Bari, Farida Yeasmin | Juyena, Nasrin Sultana
Introduction: The ovarian follicular dynamics, vaginal electrical resistance (VER), progesterone (P4) and oestrogen (E2) profiles were investigated during the oestrous cycle in four indigenous ewes. Material and Methods: Daily VER values were recorded with a heat detector. The follicles were observed and measured by trans-rectal ultrasonography. Blood was collected daily for hormonal profiles. Results: A significant variation in VER values (P < 0.05) in oestrus by ewes and position in the sequence of cycles was observed. Trans-rectal ultrasonography of ovaries revealed the presence of 2–4 waves of follicular growth. Study of hormonal profiles by ELISA revealed a positive correlation between E2 concentration and development of follicles and a negative correlation between P4 concentration and their development. The concentrations of oestradiol increased in oestrus and then decreased to a basal level. Follicular growth was accompanied by a rise in the concentration of serum oestradiol. Inversely, when follicles received the stimulation for ovulation, concentration of progesterone started to fall, but after ovulation, it climbed back to its peak and remained at this state until next ovulatory follicle reached its maximum diameter. Conclusion: This study could help to set up a manipulative reproductive technique for improving genetic values in indigenous sheep.
Show more [+] Less [-]Pilot study for the presence of fungal metabolites in sheep milk from first spring milking
2018
Piątkowska, Marta | Sulyok, Michael | Pietruszka, Katarzyna | Panasiuk, Łukasz
A mini-study of 20 raw milk samples was conducted to examine the spectrum of fungal metabolites in sheep milk from the first spring milking. Samples were collected from randomly selected ewes in two animal flocks from the Bieszczady Mountains and analysed using liquid chromatography-tandem mass spectrometry. Out of ~700 bacterial, fungal, and plant metabolites tested for, only one mycotoxin – Enniatin B – was detected in sheep milk samples (18/20; 0.0055–0.0121 μg/kg; 0.0078 μg/kg average). The results indicated that there was no high-level exposure to fungal metabolites via consumption of raw sheep milk during the sample collection period.
Show more [+] Less [-]Alterations in pregnancy-associated glycoprotein concentrations of pregnant sheep experimentally infected with bovine viral diarrhea virus
2021
Lear, Andrew | Pohler, Ky | Sula, Mee-Ja M. | Kiupel, Matti | Mulon, Pierre-Yves | Caldwell, Marc
OBJECTIVE To compare pregnancy-associated glycoprotein 1 (PAG1) concentrations in maternal (jugular vein) and fetal (uterine vein) circulations and amniotic fluid samples between pregnant ewes that were and were not experimentally infected with bovine viral diarrhea virus (BVDV). ANIMALS 11 healthy pregnant yearling ewes. PROCEDURES Before study initiation, all ewes were naïve to BVDV and confirmed pregnant by transabdominal ultrasonography at approximately 60 days of gestation. At 65 days of gestation, ewes were intranasally inoculated with a noncytopathic BVDV type 1b strain (concentration, 107 TCID50/mL; 2 mL/nostril; n = 6) or an equal volume of BVDV-free viral culture medium (control; 5). A blood sample was collected for measurement of PAG1 concentration before inoculation. At 80 days of gestation, each ewe was anesthetized and underwent an ovariohysterectomy. While sheep were anesthetized, blood samples from the jugular and uterine veins and an amniotic fluid sample were collected for measurement of PAG1 concentration. Fetal tissues underwent real-time PCR analysis for BVDV RNA, and placental specimens underwent histologic evaluation and immunohistochemical staining for BVDV antigen. RESULTS At 80 days of gestation, BVDV RNA in fetal tissues and mild placentitis were detected in 5 of 6 BVDV-inoculated ewes. Mean PAG1 concentrations in the maternal and fetal circulations of BVDV-inoculated ewes were significantly less than those in control ewes. Mean amniotic fluid PAG1 concentration did not differ significantly between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE Concentration of PAG1 in the maternal circulation may be a useful biomarker for determining placental health in sheep after viral infection of the reproductive tract.
Show more [+] Less [-]Maternal and fetal arterial blood gas data in normotensive, singleton, isoflurane anesthetized sheep at 124-126 days of gestation
2017
Loughran, C. M. | Kemp, M. W. | Musk, G. C.
The aim of this case series was to describe the differences between maternal and fetal blood-gas results during anesthesia. Sixteen singleton adult merino ewes weighing 60.1 ± 5.1 kg at 125.7 d (124 to 126 d) gestation were anesthetized. Maternal (radial) and fetal (umbilical) arterial blood gas samples were collected 79 ± 6 min after the start of anesthesia if maternal mean arterial pressure (MAP) was stable and > 65 mmHg. Fetal pH, partial arterial pressure of oxygen (PaO2), glucose, arterial hemoglobin oxygen saturation (SaO2), sodium, and chloride were significantly lower and fetal partial arterial pressure of carbon dioxide (PaCO2), lactate, hematocrit, total hemoglobin, potassium, and calcium were significantly higher than maternal blood-gas values. Fetal pH, PaO2, and BE were lower and fetal lactate was higher than fetal umbilical arterial samples previously reported, which may indicate a non-reassuring fetal status. Further refinement of the ovine experimental model is warranted with fetal monitoring during maternal anesthesia.
Show more [+] Less [-]Determination of the minimum alveolar concentration of isoflurane that blunts adrenergic responses in sheep and evaluation of the effects of fentanyl
2016
Barletta, Michele | Kleine, Stephanie A. | Hofmeister, Erik H. | Thoresen, Merrilee | Peroni, John F. | Knych, Heather K. | Scharf, Alexandra M. | Quandt, Jane E.
OBJECTIVE To determine the minimum alveolar concentration that blunts adrenergic responses (MAC(BAR)) for isoflurane and evaluate effects of fentanyl on isoflurane MAC(BAR) in sheep. ANIMALS 13 healthy adult Dorset-cross adult ewes. PROCEDURES In a crossover design, each ewe was anesthetized 2 times for determination of isoflurane MAC(BAR). Anesthesia was induced with propofol administered IV. Sheep initially received fentanyl (5 μg/kg, IV, followed by a constant rate infusion of 5 μg/kg/h) or an equivalent volume of saline (0.9% NaCl) solution (control treatment). After a washout period of at least 8 days, the other treatment was administered. For MAC(BAR) determination, a mechanical nociceptive stimulus (ie, sponge forceps) was applied at the coronary band for 1 minute. The MAC(BAR) values of the 2 treatments were compared by means of a paired t test. During MAC(BAR) determination, blood samples were collected for measurement of plasma fentanyl concentration. RESULTS Mean ± SD isoflurane MAC(BAR) of the fentanyl and control treatments was 1.70 ± 0.28% and 1.79 ± 0.35%, respectively; no significant difference was found between the 2 treatments. Plasma concentration of fentanyl reached a median steady-state concentration of 1.69 ng/mL (interquartile range [25th to 75th percentile], 1.47 to 1.79 ng/mL), which was maintained throughout the study. CONCLUSIONS AND CLINICAL RELEVANCE Administration of fentanyl at 5 μg/kg, IV, followed by a constant rate infusion of the drug at 5 μg/kg/h did not decrease isoflurane MAC(BAR). Further studies to determine the effect of higher doses of fentanyl on inhalation anesthetic agents and their potential adverse effects are warranted.
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