Maternal and fetal ultrasonographic characteristics, vulvar temperature, and vaginal mucous impedance as variables associated with the onset of parturition in term and induced pre-term ewes.

The aim of this study was to assess and compare ultrasonographic characteristics of maternal and fetal structures, vulvar temperatures, and vaginal mucous impedance in pregnant ewes in the term parturition group (TPG, n = 15) and induced pre-term parturition group (IPPG; n = 15). All the measurements were taken every 12 h throughout the last gestational week. Maternal and fetal structures and the fetal heart rate (HR) were assessed using ultrasonography. The vulvar temperature and vaginal mucous impedance were determined using a non-contact infrared thermometer, and an electronic estrous detector, respectively. The vulvar temperature was less in the TPG and greater in the IPPG; the end-diastolic velocities (EDVs) of the arteries of the placentome and uterus gradually increased before parturition in the IPPG (P = 0.02, P = 0.02 and P = 0.009, respectively). The placentome shear wave velocity (SWV) was greater in the ewes of the IPPG than TPG 48, 36, and 0 h before parturition (P = 0.001). The following variables were associated with the onset of parturition within the next 12 h in the ewes of the IPPG: resistance index (< 0.54) and EDV (> 0.34 cm/s) of the uterine artery; and vulvar temperature (> 37.3 °C). A fetal kidney SWV of < 1.31 m/s was associated with the onset of parturition in the next 12 h in all the ewes. Results indicate vulvar temperature and certain maternal and fetal factors detected using ultrasonograpy may aid in determining fetal maturity and/or the time of parturition in ewes.

Managing embryonic and calves losses after twin pregnancies induced by transfer of in vitro-produced Nellore embryos.

Two farms applying reproductive technology for the Nellore beef cattle were selected. Both farms had the same technology programme of oestrous synchronization and embryo transfer, but management was different, especially regarding twins pregnancies. In the present study, we followed the farms from the moment of oestrous synchronization, embryo transfer (two per cow), until delivery and first care of the calves. In farm A, cows presenting twin pregnancies (5 from 13) were submitted to delivery induction, as well as calves and cows were monitored after birth. In farm B, such management was not followed with the twin pregnant cows (31 from 49). In both farms, freemartinism was detected, but this was not a problem as none of the animals would be selected for breeding. No dystocia was observed in farm A, while 48% of the twin pregnancies in farm B ended up in dystocia. Furthermore, the mortality rate of new-born calves in farm A was 10%, while in farm B it reached 32%. Although twin pregnancies remain a concern, we showed here that proper management during and after delivery minimizes animal and economic losses.

Effect of different doses of dexamethasone on labor in Santa Inês ewes and its influence on the onset of labor and the expulsion of fetal membranes / Efeito de diferentes doses de dexametasona para a indução do parto em ovelhas Santa Inês e sua influência sobre as características do parto

The induction of labor aims to concentrate births to follow up better the parturient and the first care to the neonates. However, even if the labor induction technique with dexamethasone administration has been successfully described since the late 1970s, few studies report the technique of birth development and neonatal vitality in Santa Inês sheep. This study aimed to evaluate the efficiency of dexamethasone use in two doses (8 and 16mg) in labor induction of Santa Inês ewes at 145 days of gestation and to evaluate its effects on the birth characteristics. In this study, 58 ewes were used, raised in an extensive system in the experimental farms of UFBA, with confirmation pregnancy after fixed-time artificial insemination or controlled breeding. These female ewes were separated into three groups according to the dose of dexamethasone administered (G1 = 0mg, G2 = 8mg, and G3 = 16mg). From these births, 79 lambs were born. This study analyzed the period from induction of labor to birth, fetal presentation at birth, the weight of the placenta, and the period for placenta expulsion. The data were analyzed by the Statistical Analysis System (SAS v.9.1.3®, 2002), and the significance level considered for all analyzes was 5%. Births of induced groups occurred on average at 48.4±22.17 hours after induction, while the females with non-induced labor gave birth 131.96±41.9 hours on average after the placebo application (P<0.05), confirming the efficiency of both doses for induction of labor. The period from induction to birth did not differ (P>0.05) between the doses used. There were no differences in delivery about the fetal static relation, time to placental attachment, and weight. With this study, it can be concluded that the induction at 145 days of gestation with eight or 16mg of dexamethasone is a useful technique and does not alter the labor in Santa Inês sheep.(AU)

A indução do parto visa concentrar os nascimentos para melhor acompanhamento das parturientes e primeiros cuidados aos neonatos. Contudo, mesmo que a técnica de indução de parto, com administração de dexametasona, tenha sido descrita com sucesso desde o final da década de 70, existem estudos escassos que relatam a influência desta técnica sobre o parto em ovinos da raça Santa Inês. Dessa forma, o objetivo do estudo foi avaliar a eficácia da dexametasona em duas doses (8 e 16mg), para a indução do parto de ovelhas Santa Inês com 145 dias de gestação e avaliar os seus efeitos nas características de desencadeamento e finalização do parto. Para este estudo foram utilizadas 58 ovelhas, criadas em sistema extensivo nas fazendas experimentais da UFBA, com prenhez confirmada após inseminação artificial em tempo fixo ou monta controlada. Essas fêmeas foram separadas em três grupos, de acordo com a dose de dexametasona administrada (G1 = 0mg, G2 = 8mg e G3 = 16mg). Destes partos nasceram 79 cordeiros. Foram avaliados o período em horas da indução do parto aos nascimentos, a apresentação fetal ao nascimento, assim como o peso da placenta e o período para o delivramento. Os dados foram analisados pelo pacote estatístico Statistical Analysis System (SAS v.9.0®, 2002) sendo considerado para todas as análises o nível de significância de 5%. Os nascimentos dos grupos induzidos ocorreram em média com 48,4±22,1 horas após a indução, enquanto que as fêmeas com parto não induzido pariram em média 131,96±41,9 horas após aplicação do placebo (P<0,05), confirmando a eficácia de ambas as doses para indução do parto. O período da indução até o parto não diferiu (P>0,05) entre as doses utilizadas. Não ocorreram diferenças no parto em relação à estática fetal, tempo para o delivramento e peso da placenta nos diferentes grupos. Com este estudo, conclui-se que a indução de parto em ovelhas aos 145 dias de gestação com oito e 16 mg de dexametasona é uma técnica eficaz e que não altera o trabalho de parto nas ovelhas da raça Santa Inês.(AU)

Induction of parturition by double administration of prostaglandin F2α in sows reduces the variation of gestation length without affecting the colostrum yield and piglet performance.

The objective of the present study was to investigate whether double intra-vulvo submucosal administration of prostaglandin F2α (PGF2α) could improve farrowing synchronization compared to single administration, and the effects of the induction of farrowing on colostrum yield and piglet performances. In total, 91 sows were randomly assigned to one of three groups: i) treatment with a single or ii) double administration of PGF2α or iii) control group without any treatment. A synthetic analogue of PGF2α was administrated via the intra-vulvo submucosal route on day 114 of gestation, at 0800 hr (single administration) or at 0800 and 1400 hr (double administration). The animals were monitored during the farrowing process. The time interval from the first administration of PGF2α to the onset of parturition was compared between groups. The proportion of sows that farrowed within 32 hr of induced parturition was higher in the double administration group than in the single administration group (100 vs. 84.4%, P=0.046). The duration of farrowing was higher in single administration sows than in control (241.1 vs. 169.5 min, P=0.004) and tended to be higher than in double administration sows (241.1 vs. 190.3 min, P=0.088). Birth interval of piglets born after double administration of PGF2α was shorter than those born after a single administration (14.6 and 20.1 min, P=0.024). In sows, the induction of parturition using a double administration of PGF2α reduces variation in gestation length and significantly increases the proportion of sows with an early response to PGF2α.

External stress increases sympathoadrenal activity and prolongs the expulsive phase of foaling in pony mares.

Mares usually give birth when they perceive their environment as safe and therefore disturbance at foaling may inhibit labor. In this study, foaling mares were transferred to an unfamiliar environment at rupture of the allantochorion (stress, n = 6) or were left undisturbed (control, n = 5). The progress of foaling, heart rate, heart rate variability (HRV) and plasma catecholamine, oxytocin and cortisol concentration were determined. In stressed mares, time from rupture of the allantochorion to appearance of the fetal feet (5.3 ±â€¯1.1 vs. 1.6 ±â€¯0.4 min) and total length of fetal expulsion were longer than in controls (both p < 0.05). Heart rate decreased during the expulsive phase of foaling in control mares (p < 0.01) but increased transiently in stressed mares. Heart rate calculated as percentage of the baseline was higher in stressed than in control mares (p = 0.05). HRV variables SDRR (standard deviation of the beat-to-beat interval) and RMSSD (root mean square of successive beat-to-beat differences) increased during foal expulsion (SDRR p < 0.01 and RMSSD p < 0.05). The increase in HRV was delayed in stressed compared to control mares (SDRR and RMSSD time x group p < 0.05). Plasma epinephrine and norepinephrine concentrations calculated as area under the curve for the expulsive phase of foaling were higher in stressed than control mares (p < 0.05). Concentrations of oxytocin and cortisol were elevated during foal expulsion (both p < 0.001) but not different between groups. In conclusion, disturbance of mares during expulsion of the foal prolonged foaling. This effect is most likely mediated via increased sympathetic activity and not inhibition of oxytocin release.

Comparison of the endocrinological and immunological results of different induction of parturition methods in ewes.

OBJECTIVE: This study aimed to compare different induction of partu -rition (IP) methods in terms of endocrinological and immunological parameters in ewes and lambs. MATERIALS AND METHODS: A total of 24 ewes and their respective 24 lambs were studied. Groups of six ewes were induced on the 138th day: groups I (control), II (dexamethasone), III (aglepristone) and IV (aglepristone + dexamethasone). Blood samples were taken from the ewes from IP to 2 days postpartum at 12-hour intervals for the prolactin and oxytocin analyses. Colostrum and blood samples were collected from the lambs at 0, 12, 24, 36 and 48 hours for the IgG analysis. The prolactin, oxytocin and IgG levels were measured by ELISA. RESULTS: A significant difference was found in prolactin levels in all groups and in the colostral IgG level in group IV with respect to the sampling time. Additionally, a significant difference in prolactin level was found at 24 hours postpartum between group IV and groups I and III. A significant difference in the colostral IgG level was determined at 24 hours after parturition between group III and the other groups and at 48 hours after parturition between groups II and III. A positive and significant correlation between the colostral and serum IgG levels of the lambs was found at 24 hours in groups I and II. CONCLUSION AND CLINICAL RELEVANCE: Although varying individual results were found within the groups, the endocrinological and immunological results did not suggest any superiority among the IP methods. Considering the presented study results, a single dose of aglepristone may be used alone or in combination with dexamethasone for I P.

The effect of farrowing induction on colostrum and piglet serum immunocrits is dependent on parity.

Farrowing induction is a common practice among swine producers to manage timing of farrowing and the labor associated with farrowing. In this experiment, the effect of induction of labor using cloprostenol on Day 114 of gestation ( = 88) was compared to our standard farrowing protocol at USMARC (natural farrowing with induction using cloprostenol on Day 116 if needed, = 82) in gilts and sows up to fourth parity. In a subset of dams ( = 10 each treatment), colostrum was collected within 30 min of birth of the first piglet, and at 4, 8, 12, and 24 h. Colostrum samples were measured for immunoglobulin G (IgG) using the immunoglobulin immunocrit and porcine IgG specific ELISA, and for total protein. Blood samples were collected from each live piglet on d 1 of age and measured using the immunocrit assay, and average immunocrit was calculated for each litter. Total piglets born and born alive, birth and weaning weights, and the stillbirth rate and preweaning mortality rate were also recorded for each litter. Results indicated that induction of farrowing by cloprostenol treatment on d 114 reduced average gestation length by 0.5 to 1 d depending on parity ( < 0.05), and reduced overall colostrum immunocrit, IgG and total protein ( < 0.05). Colostrum immunocrits and IgG concentrations were well correlated ( = 0.89; < 0.01) but IgG was curvilinearly related to total protein. Litter average immunocrits were similar in gilts between treatments, but were reduced in later parity sows induced to farrow using cloprostenol on d 114 of gestation. Total born, born alive, birth and weaning weights, and stillbirth and preweaning mortality rates were unaffected by treatments. In conclusion, induction of farrowing using cloprostenol injection on d 114 reduced colostrum IgG concentrations in dams, but this was reflected in a reduction in litter average immunocrit only in later parity sows. This reduction in litter average immunocrit was not sufficient to influence preweaning mortality, but other effects are possible given the reported influence of colostrum on growth and reproductive traits.

Colostrum yield and litter performance in multiparous sows subjected to farrowing induction.

The consumption of colostrum at a low level can compromise the survival and growth of piglets. Therefore, this study aimed to evaluate the effect of farrowing induction on colostrum yield, IgG concentration and the survival and performance of piglets until the weaning. Sows of parity 3 to 7 were assigned into two groups: Control (n = 48), sows with spontaneous farrowing; and induction (n = 48), sows induced to farrow on day 114 of gestation with a PGF2 analogue. Colostrum and blood samples were collected from the sows, at farrowing and 24 hr later. Blood samples from the piglets were collected at 24 hr after birth. The performance of the piglets was evaluated in a subsample of 28 litters from each group. All piglets were weighed at 7, 14 and 20 days of age. The farrowing length, the number of piglets born alive, stillborn piglets, weight at birth, litter weight at birth and colostrum yield were not significantly affected (p > .05) by farrowing induction. There was no difference between the groups (p > .05) in the percentage of sows with obstetric interventions. Serum IgG concentration, in both sows and piglets, and colostrum IgG concentration were similar between the groups (p > .05). Furthermore, survival rate, piglet weight and litter weight at 7, 14 and 20 days of age were also similar between the groups (p > .05). Therefore, it can be concluded that the farrowing induction performed on day 114 of gestation does not affect the colostrum yield, the IgG concentration in colostrum and serum of piglets, and the litter performance until the weaning.

Pharmacokinetics of ceftiofur sodium in equine pregnancy.

Eleven pregnant pony mares (D270-326) were administered ceftiofur sodium intramuscularly at 2.2 mg/kg (n = 6) or 4.4 mg/kg (n = 5), once daily. Plasma was obtained prior to ceftiofur administration and at 0.5, 1, 2, 4, 8, 12, and 24 hr after administration. Eight pony mares were re-enrolled in the study at least 3 days from expected foaling to ensure steady-state concentrations of drug at the time of foaling. Mares were administered ceftiofur sodium (4.4 mg/kg, IM) daily until foaling. Parturition was induced using oxytocin 1 hr after ceftiofur sodium administration. Allantoic and amniotic fluid, plasma, and colostrum samples were collected at time of foaling. Serial foal plasma samples were obtained. Placental tissues were collected. Desfuroylceftiofur acetamide (DCA) concentrations were measured in samples by high-performance liquid chromatography (HPLC). Mean (±SD) peak serum concentrations of DCA were 3.97 ± 0.50 µg/ml (low dose) and 7.45 ± 1.05 µg/ml (high dose). Terminal half-life was significantly (p = .014) shorter after administration of the low dose (2.91 ± 0.59 hr) than after administration of the high dose (4.10 ± 0.72 hr). The mean serum concentration of DCA from mares at time of foaling was 7.96 ± 1.39 µg/ml. The mean DCA concentration in colostrum was 1.39 ± 0.70 µg/ml. DCA concentrations in allantoic fluid, amniotic fluid, placental tissues, and foal plasma were below the limit of quantification (<0.1 µg/ml) and below the minimum inhibitory concentration of ceftiofur against relevant pathogens. These results infer incomplete passage of DCA across fetal membranes after administration of ceftiofur sodium to normal pony mares.

Parturition induction in ewes by a progesterone receptor blocker, aglepristone, and subsequent neonatal survival: Preliminary results.

The clinical effects of aglepristone treatment to induce parturition in ewes and their newborns were reported. Three experimental groups were defined: group AG5 (n = 5), group AG10 (n = 5), and group CG (n = 5) in which ewes were injected twice with 5, 10 mg/kg of aglepristone, and saline solution of ewes, respectively. Different parameters associated with parturition in ewes and their newborns were investigated. Serum progesterone, oxytocin, and free and conjugated total estrogens were measured after treatments until parturition. No statistical difference was found from first aglepristone administration to onset of lambing between AG5 and AG10 (23.90 ± 6.20, 40.00 ± 6.71 hours). Parturition induction in two groups shortened the gestational length significantly compared with the control group (P = 0.003). Dystocia was observed in two ewes in group AG10. The placental weight showed statistically significant difference only between the AG10 and CG (P = 0.039), but no difference was observed in the placental expulsion period between the groups. Decrease in food consumption 24 to 36 hours after parturition in all ewes and skin necrosis in an ewe in group AG5 were observed. Progesterone concentration was significantly lower in AG5 than that in ewes in group AG10 and CG (P < 0.05). No difference was observed in concentrations of free total estrogens and oxytocin between groups. The body temperature of lambs was significantly different between AG10 and CG groups both right after (P = 0.011) and 12 hours after parturition (P = 0.014). The lambs in CG had the highest mean birth weight (4.29 ± 0.28 kg), which was significantly different from the induced groups. No significant difference of blood pH and blood gases values between groups was identified both at birth and 12 hours after parturition for lambs. Significant differences could clearly be observed in total protein and blood urea nitrogen and total protein findings 12 hours after parturition (P < 0.05), whereas no difference was found in blood glucose, albumin, inorganic phosphor, triglyceride, or total cholesterol parameters. The results of this study show that the administration of aglepristone to induce parturition can precisely control lambing time without any side effects in either mothers or lambs.

Stress response and cardiac activity of term and preterm calves in the perinatal period.

This study tested the hypothesis of gestational age affecting fetal cardiac activity and the stress response at birth. Heart rate (HR), heart rate variability variables, SD of the beat-to-beat interval and root mean square of successive beat-to-beat differences, and postnatal salivary cortisol concentration were studied in calves born at term (Term, n = 7, gestation length 286.3 ± 2.1 days) or after induction of parturition (Preterm, n = 7, gestation length 279.6 ± 0.2 days). Observation periods covered the last month of gestation (phase A), the last hours before birth including the first stage of labor (phase B), and the neonatal period (phase C). Fetal HR decreased in phase A (P < 0.001) and did not differ between groups. During phase B, HR increased (P < 0.05) and was higher in Preterm than in Term calves in phases B (P < 0.05) and C (P < 0.01). In Term calves, heart rate variability increased from Day 6 until birth (P < 0.05). At birth, SD of the beat-to-beat interval was higher in Term than in Preterm calves (P < 0.01). On Day 1 after birth (phase C), HR accelerations were more frequent in Term than Preterm calves (P < 0.01), whereas decelerations were more frequent in Preterm calves (P < 0.05). Cortisol concentration increased postnatally (P < 0.001) and was correlated with gestation length (r ≥ 0.68, P < 0.01). Because of a certain degree of immaturity, the ability to cope with the stress of birth may be impaired in calves born 1 week before term.

The effect of parturition induction treatment on interval to calving, calving ease, postpartum uterine health, and resumption of ovarian cyclicity in beef heifers.

The aim of this study was to compare the effects of two parturition induction protocols with a nontreated control group, on interval to calving, calving ease, postpartum uterine health, and ovarian cyclicity in beef heifers. At Day 285 of gestation, 81 crossbred recipient beef heifers carrying purebred Simmental fetuses, were blocked by live-weight, body condition score, expected calving date and fetal sex, and assigned to one of three groups: (1) control (CON; no induction treatment, n = 29); (2) induction with corticosteroids (CORT; n = 27); or (3) induction with corticosteroids plus prostaglandin (CORT + PG; n = 25). Interval from induction to calving in hours and calving ease on a scale of 1 to 5 were recorded. Vaginal mucus samples were collected on Day 21 and Day 42 after calving (Day 0) by means of a Metricheck and scored on a scale of 0 to 3. Reproductive tract examinations were conducted on Day 21 and Day 42 after calving, and uterine cytology samples were obtained on Day 21. A positive cytologic sample was defined as greater than 18% neutrophils in the sample obtained via a cytobrush technique. Cows were considered to have resumed ovarian cyclicity if the presence of the CL was confirmed. Data were analyzed using the Mixed (normally distributed data) and Genmod (nonparametric data) procedures of SAS (v. 9.3). The interval from treatment to calving was longer (P < 0.0001) for CON (161.9 ± 15.12 hours) animals compared with CORT (39.7 ± 11.64 hours) or CORT + PG (32.6 ± 12.10 hours), which did not differ. Treatment did not affect calving difficulty score. There was also no difference in incidence of retained placenta between the three groups. At Day 21 postpartum, cytology score tended to be higher for both induced groups (48%) compared with the control animals (24%), but this was not the case for vaginal mucus score (CON 52%, CORT 70%, and CORT + PG 52%). A higher proportion of CON had an involuted uterus by Day 21 postpartum (69%) compared with both induced groups (CORT 48%, CORT + PG 32%). Day 21 ovarian cyclicity was higher in both CON (52%) and CORT (59%) compared with CORT + PG (29%). By Day 42, there was no difference in ovarian cyclicity or uterine involution between CON and CORT; however, a positive relationship was observed between uterine involution score on Day 21 and return to cyclicity on Day 42 in these two groups. There was a negative relationship between uterine involution score and return to cyclicity in the CORT + PG group, and these animals were slower (P < 0.05) to resume cyclicity by Day 42 with a larger proportion animals having evidence of having resumed postpartum ovarian cyclicity in both CON (P = 0.03) and CORT compared with CORT + PG on Day 42. In conclusion, the use of corticosteroid-based treatments is an effective strategy to advance parturition in full term dams and does not have a negative effect on calving progress or dam health. However, when prostaglandin is also included in the protocol, these treatments may lead to greater delay in uterine involution with increased chance of uterine infection and slower resumption of ovarian cyclicity.

Sympathoadrenal balance and physiological stress response in cattle at spontaneous and PGF2α-induced calving.

Increased cortisol release in parturient cows may either represent a stress response or is part of the endocrine changes that initiate calving. Acute stress elicits an increase in heart rate and decrease in heart rate variability (HRV). Therefore, we analyzed cortisol concentration, heart rate and HRV variables standard deviation of beat-to-beat interval (SDRR) and root mean square of successive beat-to-beat intervals (RMSSD) in dairy cows allowed to calve spontaneously (SPON, n = 6) or with PGF2α-induced preterm parturition (PG, n = 6). We hypothesized that calving is a stressor, but induced parturition is less stressful than term calving. Saliva collection for cortisol analysis and electrocardiogram recordings for heart rate and HRV analysis were performed from 32 hours before to 18.3 ± 0.7 hours after delivery. Cortisol concentration increased in SPON and PG cows, peaked 15 minutes after delivery (P < 0.001) but was higher in SPON versus PG cows (P < 0.001) during and within 2 hours after calving. Heart rate peaked during the expulsive phase of labor and was higher in SPON than in PG cows (time × group P < 0.01). The standard deviation of beat-to-beat interval and RMSSD peaked at the end of the expulsive phase of labor (P < 0.001), indicating high vagal activity. Standard deviation of beat-to-beat interval (P < 0.01) and RMSSD (P < 0.05) were higher in SPON versus PG cows. Based on physiological stress parameters, calving is perceived as stressful but expulsion of the calf is associated with a transiently increased vagal tone which may enhance uterine contractility.

Clinical observations on the course of oxytocin- or prostaglandin E2/oxytocin-induced parturition in mares.

The objective of this study was to compare the course of parturitions induced with sole oxytocin with those induced with the combination of intracervical prostaglandin E2 jelly and oxytocin. For this purpose 13 mares in advanced pregnancy were allocated to the groups pretreated with either intracervical PGE2 (experimental group) or saline (control group) two hours before intravenous oxytocin (5 IU) administration. The mares were compared with respect to cervical dilation diameter (CDD) 20 min. after oxytocin injection. Time intervals from the first oxytocin dose to: the first external signs of parturition, the chorioallantois rupture, the delivery of a foal and time interval from the delivery of a foal to the placenta separation were measured. Cervical dilatation diameter as well as proportion of mares with cervical dilatation > 20 cm were significantly higher in the group of PGE2 treated mares comparing with control group (p = 0.0115 and p = 0.0490, respectively). All time intervals measured were statistically insignificant for both groups of mares, however time intervals from the first oxytocin dose to the first external signs of parturition, to the allantochorion rupture and to the delivery of a foal, were very close to the significance level (alpha = 0.05). To conclude, PGE/oxytocin combination has positive influence on the preparation of the uterine cervix to parturition. Moreover, it seems that PGE2 pretreatment reduced total oxytocin dose for successful parturition induction and shortened time elapsing between the first oxytocin dose and the delivery of a foal what is crucial for foal's safety.

Effectiveness of different farrowing induction protocols in sows using alphaprostol on day 114 of gestation.

Farrowing induction in sows is frequently applied and different protocols were described. Most studies induce farrowing between day 111 and 113 of gestation, but hardly any later during gestation. The aim of this study was to investigate the effects of different induction protocols when applied on d114 of gestation. We randomly assigned 118 sows to four treatment groups: single injection of prostaglandin (1×PG), prostaglandin combined with oxytocin 24 hours later (PG+OT), half the dosage of prostaglandin twice with six hours interval (2×1/2PG), and a control group of which farrowing wasn't induced. All injections were administered intramuscularly in the neck on day 114 of gestation. A significantly higher percentage of sows started farrowing between 22 and 32 hours after induction in the PG+OT-group (68 per cent) and the 2×1/2PG-group (52 per cent) compared to the control group (23 per cent). The 1×PG-group (46 per cent) tended to differ from the control group (P=0.087). More sows from the PG+OT-group were constipated at farrowing (P=0.042). Farrowing duration, birth interval, per cent stillborn piglets, dystocia and other variables were similar between the groups. In the present herd and with continuous farrowing supervision, applying PG+OT or 2×1/2PG on d114 of gestation was efficient to induce onset of farrowing in most of the sows 22-32 hours after induction without considerable negative effects.

Effects of a protracted induction of parturition on the incidence of retained placenta and assessment of uterine artery blood flow as a measure of placental maturation in cattle.

The objectives of the present study were to compare the effects of a protracted and a conventional induction of parturition on the incidence of retained placenta, and to evaluate the suitability of transrectal Doppler sonography of the uterine arteries as a noninvasive method for the assessment of placental maturation. Protracted induction of labor (PIP) was precipitated in 13 cows by the administration of 1.3 mg dexamethasone im twice daily between Days 268 and 273 of gestation, and 40 mg dexamethasone im on Day 274 of gestation. For conventional induction of labor (SIP), 10 cows received 40 mg dexamethasone on Day 274 of gestation. A third group was not treated and served as control (SPON; N = 11). Blood flow volume (BFV) and resistance index in the uterine arteries were measured with Doppler sonography once a day from Day 268 of gestation until labor. After each ultrasonographic examination, blood samples for determination of steroid hormones were taken. Incidence of retained placenta was lower (P < 0.05) in group SPON (9%) compared with groups PIP (54%) and SIP (70%). In the last 7 days before parturition uterine BFV and resistance index did not change (P > 0.05) and did not differ between groups SPON, PIP, and SIP (P > 0.05). Resistance index was higher (P < 0.001) in cows with retained placenta compared with cows with released placenta, and BFV did not differ (P > 0.05) between them. Total estrogen concentrations increased by 283% (P < 0.001) in group PIP and by 60% (P < 0.05) in group SPON between Days -7 and -1 before parturition. They stayed constant (P > 0.05) until Day -2 in group SIP, but increased (P < 0.05) after the high dosage of dexamethasone within 1 day by 140%. Total estrogen levels were higher (P < 0.05) in cows with released placenta than in cows with retained placenta. In conclusion, a protracted compared with a short induction of labor results in higher estrogen levels before term, but does not affect incidence of placental retention. Neither alterations in placental maturation nor changes in steroid hormones influenced uterine blood supply. Therefore, Doppler sonography of uterine arteries is unsuitable to investigate the process of placental maturation induced by glucocorticoids in cows. Nevertheless, disturbances in the placental maturation process in cows with retained fetal membranes after parturition can be detected before parturition by a higher uterine blood flow resistance in the uterine arteries.

Altrenogest treatment associated with a farrowing induction protocol to avoid early parturition in sows.

This study investigated the effect of altrenogest treatment on the farrowing development of sows, and birth weight (BW) and piglet survival until the third day of life. Three control groups were used: (i) sows that farrowed spontaneously before 114 day of gestation (CONT <114); (ii) sows that spontaneously farrowed at ≥114 day of gestation (CONT ≥114); (iii) sows that farrowed at ≥114 day with cloprostenol treatment (CONTCLOPR). Other sows were treated with altrenogest (Regumate(®) ) for 3 days (days 111, 112 and 113 of gestation): one group gave birth spontaneously (ALT) and the other group received altrenogest until day 113 and cloprostenol on day 114 (ALTCLOPR). There were no differences (p > 0.05) in farrowing duration, BW, coefficient of variation (CV) of BW, stillborn piglets, mummified foetuses, percentage of light piglets and survival until Day 3 between sows with and without cloprostenol treatment, in both control (CONT ≥114 vs CONTCLOPR) and altrenogest-treated sows (ALT vs ALTCLOPR). Further comparisons were performed taking into account three groups: sows with early delivery (CONT <114 - farrowing before 114 days of gestation; n = 56), sows with longer gestation (CONT ≥114 - with and without cloprostenol treatment sows; n = 103) and ALT sows (with and without cloprostenol treatment; n = 105). Gestation length of CONT ≥114 and ALT sows was similar (p > 0.05), but higher than in CONT <114 sows. There were no differences (p > 0.05) between groups in farrowing duration, CV of BW, and percentages of stillborn piglets and mummified foetuses. Sows of CONT <114 group had a larger litter size and a lower BW than sows of the other two groups (p < 0.05). Sows of CONT <114 group had a higher percentage of lighter piglets and a lower piglet survival rate (p < 0.05) than ALT sows. In conclusion, altrenogest treatment proved to be an efficient method to avoid early parturition in 3-5 parity sows resulting in heavier piglets at birth.

Differences in apoptotic status in the bovine placentome between spontaneous and induced parturition.

We conducted this study to analyze apoptotic changes in the bovine placentome at spontaneous and induced parturition. Cows delivered i) after the administration of dexamethasone followed by prostaglandin F(2α) and estriol, ii) after the administration of prostaglandin F(2α) and estriol or iii) spontaneously. Prepartum changes in plasma progesterone and estradiol-17ß concentrations were similar between spontaneous and induced parturition. Messenger RNA of BCL2-related protein A1 (BCL2A1), an antiapoptotic gene, was expressed by trophoblast binucleate cells and caruncular epithelial cells. Quantitative RT-PCR showed that the expression of BCL2A1 mRNA in cotyledonary and caruncular portions was significantly lower in spontaneous parturition than induced parturition. The expression of BCL2-associated X protein (BAX) mRNA, a proapoptotic gene, was significantly higher in cotyledons at spontaneous parturition than parturition induced without dexamethasone. Caspase-3 (CASP3) mRNA and pre-activated CASP3 protein were predominantly detected in caruncular epithelial cells regardless of how parturition proceeded. Activated CASP3 protein was found in trophoblast uninucleate cells and binucleate cells rather than caruncular epithelial cells. In spontaneous parturition, intense staining of activated CASP3 was detected in caruncular epithelial cells. Spontaneous and dexamethasone-induced parturition increased apoptotic cells in the placentome compared with parturition induced without dexamethasone. The number of binucleate cells was significantly decreased in spontaneous parturition. The present results suggest that although the clinical dose of dexamethasone induces apoptosis in the placentome at term, neither dexamethasone nor prostaglandin F(2α) evoke normal physiological changes in the placentome during delivery such as a change in the balance of apoptosis-related genes and disappearance of binucleate cells.

Pancreatic endocrine function in newborn pony foals after induced or spontaneous delivery at term.

REASONS FOR PERFORMING STUDY: During the switch from parenteral to enteral nutrition at birth, endocrine glands such as the pancreas must assume a glucoregulatory role for the first time if the neonate is to survive the transition to extrauterine life. OBJECTIVES: To determine the adaptations in pancreatic endocrine function during the neonatal period in term pony foals delivered by different methods. METHODS: By measuring insulin and glucagon concentrations, pancreatic alpha and beta cell responses to exogenous glucose (0.5 g/kg bwt) and arginine (100 mg/kg bwt) and to endogenous muzzling for 90 min were determined periodically over the first 10 post natal days in foals born spontaneously (n = 8) or by induction of labour with oxytocin at term (n = 7). RESULTS: Pancreatic alpha and beta cell function changed with post natal age in a manner related to the method of delivery. Induced foals had 2-3 fold greater beta cell responses to exogenous glucose and arginine, despite similar glucose and alpha-amino nitrogen clearances compared with spontaneously delivered foals. Pancreatic beta cell responses to glucose decreased by 50% while those to arginine doubled with increasing age in induced but not spontaneously delivered foals. In contrast, pancreatic alpha cell responses to arginine doubled with increasing age in foals born spontaneously but not by induction. These differences in pancreatic endocrine cell function with delivery method were associated with 2-3 fold higher cortisol levels in the induced foals and with differences in the absolute and age-related changes in basal concentrations of glucose, alpha-amino nitrogen and insulin. CONCLUSIONS: Induced delivery leads to changes in pancreatic beta cell sensitivity to glucose and/or tissue insulin resistance in association with persistent neonatal hypercortisolaemia. POTENTIAL RELEVANCE: The altered post natal development of pancreatic endocrine function with induced delivery may compromise glucoregulation and adaptation to enteral nutrition in neonatal foals with potential consequences long after birth.

Absorção de IgG via colostro em leitões biológicos e adotados após a uniformização da leitegada / Absorption of IgG via colostrum in biological piglets and adopted piglets after crossfostering

Nove fêmeas de quinto parto (OP5) foram imunizadas com 4mg e 2mg de albumina sérica bovina (BSA) aos 70 e 100 dias de gestação, respectivamente. A uniformização da leitegada foi realizada 4,9±1,9h após o nascimento, antes de os leitões efetuarem a primeira mamada. As leitegadas foram compostas por cinco leitões biológicos (LB) e cinco leitões adotados (LA), com pesos semelhantes ao nascimento. Foram coletadas amostras de sangue dos leitões ao nascimento e 24h após, das fêmeas ao pós-parto e de colostro de cada grupo de tetos ao parto e 24h após. As amostras de soro e colostro foram quantificadas para IgG pelo ELISA indireto. A densidade ótica de IgG anti-BSA (DOIgG-BSA) dos leitões (24h de vida) foi correlacionada com a das fêmeas. A DOIgG-BSA entre LB e LA foi semelhante, assim como entre os grupos de tetos, ao parto e 24h após. Entretanto, ocorreu redução na DOIgG-BSA do parto até 24h após. LB e LA absorveram a mesma quantidade de IgG via colostro, quando a uniformização foi realizada até 5h pós-parto, independentemente do teto em que os leitões mamaram, uma vez que esses possuem a mesma concentração de IgG.

Nine sows of fifth parity (PO5) were immunized with 4mg and 2mg of bovine serum albumin (BSA) at 70 and 100d of gestation, respectively. Cross fostering was performed 4.9±1.9h after birth, before piglets had their first suckling. Litters were composed of five biological piglets (BP) and five adopted piglets (AP), with similar weight at birth. Blood samples were collected from piglets (at birth and at 24h of life) and from females (after farrowing) and colostrum from each group of teats (at farrowing time and after 24h). Samples of serum and colostrum were quantified to IgG by indirect ELISA. Optical density of IgG anti-BSA (ODIgG-BSA) from piglets (24h of life) was correlated with dams. ODIgG-BSA was similar among BP and AP, as well as among pairs of teats (at farrowing time and after 24h). However, there was a decrease in ODIgG-BSA from farrowing up to 24h after birth. BP and AP absorbed the same amount of IgG via colostrum, when cross fostering was evaluated 5h after farrowing, regardless of the teat suckled, since these have the same concentration of IgG.