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Summary Reasons for performing study: In horses, serum cortisol concentration is considered to provide an indirect measurement of stress. However, it includes both free and bound fractions. The sampling method is also invasive and often stressful. This is not the case for salivary cortisol, which is collected using a more welfare-friendly method and represents a part of the free cortisol fraction, which is the biologically active form. Objectives: To compare salivary and serum cortisol assays in horses, in a wide range of concentrations, using an adrenocorticotropic hormone (ACTH) stimulation test, in order to validate salivary cortisol for stress assessment in horse. Methods: In 5 horses, blood samples were drawn using an i.v. catheter. Saliva samples were taken using swabs. Cortisol was assayed by radioimmunoassay. All data were treated with a regression method, which pools and analyses data from multiple subjects for linear analysis. Results: Mean ± s.d. cortisol concentrations measured at rest were 188.81 ± 51.46 nmol/l in serum and 1.19 ± 0.54 nmol/l in saliva. They started increasing immediately after ACTH injection and peaks were reached after 96 ± 16.7 min in serum (356.98 ± 55.29 nmol/l) and after 124 ± 8.9 min in saliva (21.79 ± 7.74 nmol/l, P

Contents Thirteen female Bedouin goats living in arid land of Algeria Sahara desert were used in this study. These goats were pregnant but they sustained an abortion because of unidentified causes. None of the goats showed any signs of general disease. Plasma concentrations of caprine pregnancy-associated glycoproteins (cPAGs) and progesterone (P4) were determined during pregnancy using radioimmunoassay. The cPAGs concentration was undetectable (

This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), lactation number, milk production at pregnancy diagnosis, plasma progesterone concentration, season of gestation (warm period, March-November vs cool period, December-February), and day of gestation (40, 90, 120, 150, 180 and 210). Pregnancy was diagnosed by transrectal ultrasound on day 40 post-insemination and by palpation per rectum on days 90, 120, 150, 180 and 210. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The relative contributions of the different factors on PAG-1 concentrations were evaluated by GLM repeated measures analysis of variance. No significant effects of the herd, foetal sex, milk production, lactation number and plasma progesterone concentrations were observed. In contrast, twin pregnancy, the use of Limousin semen and conception during the cool period were correlated with significantly increased plasma PAG-1 concentrations throughout gestation. Our data indicate that both cow well-being during early placental development, determined in our conditions by reduced heat stress when conception occurred in the cool season, and crossbreed pregnancies lead to improved PAG-1 production throughout the gestation period.

The measurement of serum or plasma PAG concentrations is currently used as a specific method for pregnancy diagnosis in cattle. In this study, the correlation between five radioimmunoassay systems (RIA-497, RIA-706, RIA-780, RIA-809 and RIA-Pool) developed for measurement of PAG concentrations in ruminant species was investigated in plasma from pregnant Friesian Holstein females. Plasma PAG concentrations (ng/mL) measured by different RIA systems were significantly correlated between them ( > or = 0.81; P

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod, season, milk production, Neospora caninum -seropositivity, twin pregnancy, and plasma concentrations of pregnancy associated glycoproteins-1 (PAG-1), progesterone and cortisol. Pregnancy was diagnosed by trans-rectal ultrasonography on Day 40 post-insemination and by palpation per rectum on Days 90, 120, 150, 180 and 210 or until abortion in aborting cows. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The study population was comprised of 73 non-aborting (54 Neospora- seropositive cows) and 20 aborting cows (all Neospora- seropositive) cows. In non-aborting cows, GLM repeated measures of analysis of variance revealed that lactation number and days in milk had no effect on plasma prolactin concentrations throughout gestation, whereas high plasma prolactin concentrations were significantly associated with high plasma levels of cortisol and PAG-1, with Neospora -seropositivity, positive photoperiod (increasing day length), twin pregnancy, and with low plasma progesterone concentrations. An interaction among plasma prolactin, plasma cortisol and milk production was observed in that plasma prolactin concentrations differed significantly throughout gestation and were highest in high-producing cows with high cortisol levels. In Neospora -seropositive non-aborting versus aborting cows, mean prolactin concentrations failed to differ on Days 40, 90, 120, 150 and 180 of pregnancy, whereas prolactin values were significantly lower ( P =0.03) in aborting animals on Day 210 of pregnancy. Our results indicate that a positive photoperiod and Neospora -infection lead to increased plasma prolactin concentrations throughout gestation. Reduced prolactin concentrations detected in Neospora -seropositive aborting cows compared to non-aborting animals suggests a protective effect of prolactin in N. caninum infection.

The aim of the present study was to determine whether certain animal- or management related factors could affect plasma progesterone concentrations on Day 42 of gestation in high producing dairy cows. Factors affecting early fetal loss were also analyzed. The study population was comprised of 199 pregnant cows classified as having high (or =9 ng/ml) or low (9 ng/ml) plasma progesterone concentrations. Through logistic regression procedures it was determined that, based on the odds ratio, cows with two or more corpora lutea were three times more likely to have high progesterone concentrations than cows with a single corpus luteum. Low producing cows during the warm season were 2.86 times more likely to have high progesterone concentrations than the remaining cows. Primiparous cows with high concentrations (4 ng/ml) of pregnancy associated glycoprotein-1 (PAG-1) were 2.73 times more likely to have high progesterone concentrations than the remaining cows. Of the 199 pregnancies, 25 (12.6%) suffered early fetal loss: 22/136 (16.2%) during the warm season and 3/63 (4.8%) during the cool season, all in cows without additional corpora lutea. Based upon the odds ratio, cows without an additional corpus luteum were 3.67 times more likely to suffer fetal loss during the warm season than during the cool season. Our results indicate that milk production, the presence of two or more corpora lutea and plasma PAG-1 concentrations can affect plasma progesterone concentrations at the onset of the fetal period. The presence of an additional corpus luteum strongly diminished the risk of early fetal loss during the warm period.

In mammals, thyrotropin, or thyroid-stimulating hormone (TSH), assay is used for the diagnosis of primary hypothyroidism. Hypothyroidism is the most common type of thyroid disorder in cattle. The aim of this study was to develop and validate, under physiologic and pathologic conditions, a radioimmunoassay (RIA) for bovine TSH (bTSH). Double RIA was performed with purified bTSH and specific bovine antiserum. Laboratory validation included research of minimal detection limit, accuracy, and reproducibility. The physiologic validation included a thyrotropin-releasing hormone (TRH) challenge performed on euthyroid cows and a follow-up of bTSH concentration over a 24-hour period. Furthermore, bTSH concentration was assayed in a large population of healthy dairy and beef cows to define reference interval. The pathologic validation was made by assaying bTSH and thyroid hormones on healthy and goitrous newborn calves. The minimum detection limit (MDL) for bTSH assay was 1.3 μU/ml. The recovery was 101% to 106%. The intra- and interassay coefficients of variation (CVs) ranged from 5% to 11% and 11% to 15%, respectively. The RIA covered the whole range of physiologic bTSH values, as shown by bTSH values induced by TRH-challenge. A pulsatile secretion of bTSH was observed, accompanied by a diurnal variation with lower night values than day values. Reference intervals of bTSH ranged from 1.3 to 13.0 μU/ml for beef and dairy breeds. Finally, bTSH easily discriminated goitrous newborn calves from healthy ones, leading to the definition of a cutoff value of 35 μU/ml. The bTSH assay positively reacted to physiologic and pathologic conditions. The accuracy and precision of the RIA were satisfying.

The essential role played by progesterone in the maintenance of pregnancy is unequivocal; however, the effects of progesterone on the secretory patterns of placental and pituitary molecules during the gestation period are not well defined. The objective of this study was to describe pregnancy-associated glycoprotein (PAG) concentrations (measured by RIA-497 and RIA-Pool) in pregnantfemales with progesterone concentrations lower (low-P4 group,n = 20) or higher (high-P4 group,n = 17) than the meanof 8.74 ng/mL on Day 21 (AI = Day 0). Luteinizing hormone (LH) and prolactin concentrations were also measured in both groups. Throughout the study period, blood samples were collected on Days 0, 21, 45, 60, and 80 from 37 females that were confirmed to be pregnant. PAG concentrations measured by both RIA-497 and RIA-Pool tended to be higher in high-P4 group than in low-P4 group from Day 30 until Day 80. On Day 80, plasma PAG concentrations that were measured using RIA-497 were observed to be higher (P < 0.05) in the high-P4 group than in the low-P4 group (10.2 � 8.7 ng/mL versus 6.9 � 3.8 ng/mL). Concentrations of LH on Day 60 and prolactin on Day 80 were observed to be significantly lower (P < 0.05) in the high-P4 group. There was a tendency for the concentrations of LH (Days 45 and 80) and prolactin (Days 30, 45, and 60) to be lower in cows in the high-P4 group than in the low-P4 group. Our results suggest the existence of a relationship among the concentration levels of progesterone, PAG, LH, and prolactin during early pregnancy.

The objective of this study was to evaluate the effects of GnRH administered at Day 12 post-AI on the reproductive performance of dairy cows. Holstein-Friesian dairy cows (n=103) on a large Hungarian dairy farm were allocated randomly to treated (n=54) or control (n=49) groups. Twelve days after AI, treated cows received a GnRH agonist i.m., while the control group received a placebo (physiological saline). Progesterone radioimmunoassay was used to determine the correct timing of artificial insemination (Day 0) and the incidence of luteal insufficiency on Day 12. Ultrasonography and radioimmunoassay for pregnancy-associated glycoprotein were used to detect pregnancy and late embryonic/fetal mortality between Days 32 and 55 after AI. Three cows from each group were inseminated when progesterone concentrations were1.0 ng/mL, and six cows (four from the treated and two from the control group) had luteal insufficiency (progesterone1.0 ng/mL) on Day 12. Late embryonic/fetal mortality occurred in three treated cows and in two control cows. When these cows were removed from the model, calving rates after first service were 59.6% (28/47) and 59.1% (26/44) for treated and control cows, respectively (P0.05). There was no significant difference between treated and control cows when they were inseminated before or after Day 100 from calving. In summary, administration of a GnRH agonist on Day 12 after AI did not improve reproductive performance in dairy cows. However, our approach may be used for the field evaluation of different treatment protocols.

Lactating dairy cows (n = 72) with a mature corpus luteum (CL) (diameter of > or = 17 mm) determined by ultrasonography and having a follicle with a diameter of > or = 10 mm were randomly assigned to four groups. Cows were treated with cloprostenol i.m. once or twice, or with dinoprost i.m. once or twice with an 8-h interval. The ovaries of each cow were scanned daily by transrectal ultrasonography to measure the changes in the areas of CL and the largest follicle and to determine the occurrence of ovulation. Oestrus was verified twice daily. In addition, blood sample was withdrawn from each cow daily for measuring progesterone (P4) concentrations. Significant decreases in the percentage changes relative to areas of CL and P4 concentrations or increases in the percentage changes in the area of the largest follicle on day 0 were detected in each group during the experiment. However, the type of the drug and the number of the treatments had no significant effect on those parameters. Cows ovulated with or without showing oestrus (group A) and cows exhibiting no oestrus and ovulation (group B) were also evaluated. In contrast to the mean area of the CL and the mean concentration of P4 on day 0, the mean area of the largest follicles between the two groups on day 0 differed significantly. Significant decreases in the percentage changes relative to the area of the CL and P4 concentration or increases in the percentage changes relative to the area of the largest follicle during the experiment were detected in both groups; however, there were no group differences. Treatment of dairy cows with two injections of prostaglandins (cloprostenol or dinoprost) at an 8-h interval resulted in more cows being observed in oestrus within 5 days after treatment and having significantly higher pregnancy rate than those treated with a single prostaglandin injection.

Summary Bone responds to exercise with changes in bone (re-)modelling, which might be monitored non-invasively with biochemical bone markers. The aim of this study was to evaluate the influence of exercise on serum osteocalcin and serum carboxy-terminal cross-linked telopeptide of type I collagen generated by matrix metalloproteinases (CTX-MMP) concentration in young racehorses. Seventy-one 2 to 4-year-old Thoroughbreds were included in this prospective infield study. Blood sampling was performed six times (i.e. six sampling cycles) during a 9-month period. Serum samples were analysed with commercial osteocalcin and CTX-MMP radioimmunoassays. Two-year-old racehorses had higher serum osteocalcin and CTX-MMP values than 3-year-old horses. Gender and training amplitude did not significantly influence serum osteocalcin and CTX-MMP values. Two-year-old horses showed an increase in osteocalcin values between cycles 2 and 3 and an increase in serum CTX-MMP values between cycles 1 and 2. Serum osteocalcin and CTX-MMP concentrations decreased between cycles 4 and 5, and 5 and 6. Three-year-old horses showed an increase in serum osteocalcin levels between cycles 3 and 4 and an increase in serum CTX-MMP concentrations between cycles 1 and 2, and 3 and 4. Serum osteocalcin levels decreased between cycles 5 and 6, whereas serum CTX-MMP levels decreased between cycles 4 and 5, and 5 and 6. Two- and three-year-old horses showed a decreased osteocalcin/CTX-MMP ratio between cycles 1 and 2. Moreover, 2-year-old horses showed an increase in the osteocalcin/CTX-MMP ratio between cycles 2 and 3. Sore shin formation did not significantly influence serum osteocalcin and CTX-MMP values. Serum osteocalcin and CTX-MMP are promising bone markers for monitoring exercise induced changes in equine bone metabolism.

The study was conducted to develop a sensitive and specific radioimmunoassay (RIA) for the measurement of pepsinogen in porcine serum, and to use this test for the determination of pepsinogen concentrations in serum samples from fetuses and pigs of different ages. Compared to a previously described RIA, major improvements were made concerning the use of specific polyclonal antibodies and the use of an appropriate buffer. The assay was able to detect pepsinogen concentrations of/=0.2 ng/mL. The recovery of pepsinogen was close to 95%. The intra-assay coefficients of variations ranged between 3.9 and 7.5% whereas the interassay ranged between 8.8 and 11.9%. These percentages correspond to a satisfactory accuracy and reproducibility of the assay. No cross-reactions were observed with the main commercially available products of the aspartic proteases family except porcine pepsin cross-reacted over 62.5 microg/mL. Pepsinogen concentrations increased steadily with increasing age of the fetuses and the pigs (P0.05). Pepsinogen concentrations (+/-SE) in fetuses of 90-100 (n=24) and 100-110 days of pregnancy (n=36) were 0.5+/-0.1 and 5.3+/-1.3 ng/mL, respectively. In pigs of 21, 98, and 213 days of age, the pepsinogen concentrations were 290.6+/-10.8, 343.1+/-17.9 and 383.5+/-15.3 ng/mL, respectively. The results demonstrate that RIA is accurate and can be used easily to assess pepsinogen concentrations in pig sera. The test may constitute a valuable tool in epidemiological surveys and in studies related to gastric diseases in pigs.

Inoculation with Actinomyces pyogenes and administration of prostaglandin (PG)F(2alpha) were used to induce late embryonic mortality (LEM) in heifers (n=8) on Days 30-38 of pregnancy in order to compare the profile for bovine pregnancy associated glycoprotein 1 (PAG1), progesterone and 15-keto-13,14-dihydro-PGF(2alpha) (PGFM). Two pregnant heifers were used as controls. Inoculation into the uterine body caused LEM, as established by ultrasonography in each heifer within 24h of treatment. When the inoculum was injected into the first part of the cervix, LEM occurred in one of two heifers (Heifer A) between 48 and 72 h after treatment. Similarly, PGF(2alpha) treatment caused LEM in three of four heifers. In six of eight heifers, PAG1 started to decrease steadily when it was accompanied by the subsequent death of the embryo. Inoculation through the cervix caused luteolysis in three of four heifers within 6-10 days after induction. After induction of LEM, PGFM concentrations showed a two to 3.8 fold increase in three of four heifers during the following six days, and from that time changed within normal ranges. The results of this study indicate that a PAG1 assay may provide an alternative method to ultrasonography for determining LEM in the cow.

The relationship between maternal caprine pregnancy-associated glycoprotein (cPAG) concentrations and fetal number was investigated in 21 nulliparous and 17 multiparous goats. Using a homologous radioimmunoassay (hm-RIA) cPAG was detected in plasma of pregnant goats from the 21st day of pregnancy. Statistical differences between goats bearing single and multiple fetuses were observed after 63 days to the end of pregnancy, except on day 133. After 126 days (3rd week pre-partum) cPAG levels began to decrease slowly in both the groups. The hm-RIA was an efficient method to describe the relationship between maternal PAG concentrations and number of fetuses in goats.

This paper evaluates the profiles obtained for caprine pregnancy associated glycoprotein (cPAG) in pregnant multiparous and nulliparous goats using the heterologous-radioimmunoassay (htPAG-RIA) and the homologous-RIA (hmPAG-RIA) systems during the pregnancy and postpartum periods. The results show that the cPAG concentrations detected through the hmPAG-RIA procedure were lower than those found through the htPAG-RIA method. No statistical differences were observed due to the maternal reproductive status (nulliparous or multiparous goats) during pregnancy using either one of the methods. However, pregnant and cyclic goats were distinguished from each other by cPAG concentrations verified through the hmPAG-RIA procedure. The lower cPAG concentrations detected through this method suggest that this system is more specific than the htPAG-RIA procedure to measure cPAG during pregnancy and postpartum period in goats. The homologous system was also an efficient method to predict pregnancies of only 35 days in both nulliparous and multiparous goats.

Plasma concentrations of pregnancy-associated glycoproteins (PAG) were determined in goats during pregnancy by two homologous radioimmunoassays that employed caprine PAG 55+62 (caPAG 55+62 ) and caprine PAG 55+59 (caPAG 55+59 ) and their specific antisera. The effects of fetal number on PAG concentrations were analysed. The concentrations of caPAG 55+62 were higher than that of caPAG 55+59 throughout pregnancy (p < 0.05). Both caPAG 55+62 and caPAG 55+59 reached maximal levels in week 8 (48.6 ± 5.0 and 30.4 ± 4.3 ng/ml, respectively), decreased between weeks 12 and 14 (45.5 ± 2.5 to 31.9 ± 2.7 ng/ml and 30.6 ± 2.1 to 15.8 ± 2.8 ng/ml, respectively, p < 0.01) and remained relatively constant until parturition. Twin-bearing goats had higher PAG concentrations than single-bearing animals, but the difference was only significant in week 4 (52.3 ± 3.7 versus 30.9 ± 3.9 ng/ml and 18.9 ± 1.7 versus 12.6 ± 2.0 ng/ml, for caPAG 55+62 and caPAG 55-59 , respectively, p < 0.05). This is the first study of PAG concentrations in goat throughout pregnancy by a homologous radioimmunoassay system. The profiles of caPAG 55+62 and caPAG 55+59 were closely parallel. Concentrations of PAG were lower than those obtained by a heterologous radioimmuno-assay and their patterns were also different, due to a different specificity of the antisera used in heterologous system. Goats that delivered twins had higher PAG concentrations at the time of implantation than those that delivered a single fetus, indicating that PAG concentrations provide a useful measure of the trophoblast secretory activity.

The virulence of five amyxomatous myxoma virus (MV) strains, the clinical and pathogenetic effects of which had been studied previously in specific pathogen-free (SPF) rabbits, was determined by inoculation of five groups of 10 crossbred New Zealand White/Californian conventional rabbits. A much more acute myxomatosis syndrome was produced in conventional rabbits than that reproduced previously in SPF animals. However, the main clinical signs were of the respiratory type. The MV strains MYX 254/95 and 801 appeared very virulent, killing all the inoculated animals. The strains MYX 217/95, MYX 555/94 and Saint Benoist were somewhat attenuated, killing only seven, six and six rabbits, respectively. Extensive lung lesions due to supervening bacterial infections were observed in 36 of the 39 rabbits that died. Lethality was found to be a better estimate of virulence than mean survival time. By 98 days after viral inoculation, all the surviving animals had completely recovered. At that time, they were immunosuppressed by treatment with adrenocorticotrophic hormone (ACTH) for 10 days to determine whether they still harboured the virus. After the ACTH treatment, eight of the 11 surviving rabbits showed clinical signs that resembled amyxomatous myxomatosis. All the virological examinations performed on naso-conjunctival exudate, on mononuclear cells, on eyelids and on ovaries remained negative but infectious virus was isolated from the testes of three of six surviving male rabbits.

Presented here are the profiles of pregnancy-associated glycoprotein (PAG) concentrations in blood collected weekly from goats experiencing maintained and unsuccessful pregnancies. The analysis of these profiles clearly indicated 4 different situations: the pseudopregnancy syndrome, abortion between Days 89 and 137, parturition of 1 dead and 1 live fetus, and expulsion of macerated or mummified fetuses after full term. A marked reduction in PAG concentration at any time during pregnancy was followed by an event such as abortion or the expulsion of a dead fetus at term or later.

Pregnancy diagnosis is a critical procedure for monitoring goat reproductive performance. In the present investigation, pregnancy-associated glycoprotein (PAG) profiles during pregnancy and first month postpartum, as well as progesterone (P4) concentrations throughout pregnancy, were determined in native goats from the north-east of Brazil. A total of 30 goats (Moxoto, n = 19 and Caninde, n = 11) were used. Peripheral blood was collected on days 0 (Day 0 = AI), 11, 16, 18, 20, 24 and 30 after AI. Samples were subsequently collected every 2 weeks until day 145, and weekly during the first month postpartum. The levels of PAG and P4 were determined by radioimmunoassay (RIA). The profiles of PAG were not different between the breeds throughout pregnancy. However, a significant effect of the week of pregnancy (p

Phagocytosis and oxidative burst activity of polymorphonuclear neutrophil leukocytes (PMN) isolated from blood and pregnancy-associated glycoprotein (bPAG) concentrations in plasma were evaluated in two longitudinal studies in dairy cows from 3 weeks before until 5 weeks after calving, carried out in the United States and in Europe. Ingestion of Staphylococcus aureus by blood PMN increased during the first week after calving and normalised 3 weeks post-partum. Phagocytosis of Escherichia coli did not change in the early post-partum period. In both studies, a significant decrease in oxidative burst activity of PMN was observed between 1 and 3 weeks after calving. In all cows, a very significant increase in plasma bPAG concentration was found between 1 week before and 2 weeks after calving. The peak of bPAG concentration in plasma immediately preceded the alterations of blood PMN functions. These results suggest that bPAG may be associated with inhibition of PMN function of dairy cows during the early post-partum period.

A radioimmunoassay of the undecapeptide substance P (SP) and its application in rabbit lung superfusate has been developed. The assay was based on the use of a radioactive tracer, 125 I-SP-Tyr8, which showed, with an excess of antibodies, a specific binding greater than 90% and a nonspecific binding lower than 2%. This tracer was stable for 4 weeks at −20°C. Its specific radioactivity was 384 Ci/mmol. The assay’s lower limit of detection was 10 pg/ml (0.7 fmol). The determination of SP in rabbit lung perfusate required extraction and concentration using octadecylsilane cartridges. Under these conditions, the recovery of SP from experiments on lung perfusates ( n = 4) was 75.0 ± 4.5%, and the intraassay and interassay coefficients of variation were 7.3 ± 1.9% and 10.7 ± 1.3%, respectively. Amounts of SP released in rabbit lung perfusates were determined following stimulation of pulmonary C fibers with capsaicin (10 −4 M). During the stimulation period, the values of SP from lung perfusates ( n = 6) increased significantly when compared with baseline values.

7 pages, 3 figures.-- Available online 9 Dec 1997., Ovine pregnancy-associated glycoprotein (oPAG) and progesterone (P4) concentrations were monitored weekly during the last three months of gestation and the first month postpartum in plasma of twelve Assaf ewes. The oPAG levels were determined with a heterologous RIA using bovine PAG as standard and tracer and rabbit antiserum against oPAG. The P4 levels were measured with a radioimmunological procedure with a sensitivity to less than 0.1 ngml-1. The oPAG profiles in ewes carrying a single lamb and in those carrying twins were very similar from week 9 of gestation to lambing. Ewes which had twins presented numerically higher oPAG concentrations from week 12 to lambing, but that difference was only significant (P < 0.05) at week 21. Ewes carrying twins presented higher (P < 0.05) P4 concentrations from weeks 12 to 20 of gestation than those carrying a single lamb, but afterwards there was no difference. No correlation was found between P4 and oPAG concentrations at each stage of gestation studied in any group. After lambing, P4 levels dropped rapidly in one week, whereas oPAG decreased in four weeks to basal values in both groups of ewes. No relationship (P > 0.05) was found between oPAG concentrations and lamb birth-weight at any week of gestation considered in this study. However, the lamb birth-weight was positively correlated (P < 0.10) with the P4 concentrations from weeks 9 to 19 of gestation. Results indicate that number of fetuses could influence the oPAG production in ewes during the last three months of gestation., The part of this work carried out in Liege University was supported by grants from IRSIA and FRSM. M.J. Ranilla gratefully acknowledges receipt of a scholarship from the Ministerio de Educación y Ciencia (MEC).

3 figures, 1 table.-- PMID: 16727560 [PubMed]., This study was carried out to determine ovine pregnancy-associated glycoprotein (oPAG) and progesterone (P4) levels in the serum of Churra and Merino ewes throughout gestation and the first month post partum. The oPAG levels were determined with an heterologus RIA using bovine PAG as standard and tracer and rabbit antiserum against oPAG, sensitivity was 4.0 ng/ml. The P4 levels were measured with a radioimmunological procedure, including a specific extraction step with petroleum ether (bp 60–80°C) with a sensitivity of less than 0.1 ng/ml. There were no differences (P0.05) were observed for mean weekly P4 levels between the 2 breeds. In both breeds, P4 increased throughout the whole length of gestation, with the highest level measured at Weeks 19–20, then declined 2 wk before parturition. No correlation was found between P4 and oPAG concentrations during gestation in either of the breeds. After lambing, oPAG and P4 levels decreased rapidly in 4 wk to basal values. In both breeds the oPAG concentrations at Weeks 19, 20 and 21 of gestation in ewes carrying male fetuses were higher than in those carrying female fetuses. From the results, we conclude that the breed and sex of the fetus could influence the production of oPAG., The part of this work that was carried out at Liege University was supported by grants from IRSIA and FRSM. M. J. Ranilla gratefully acknowledges receipt of a scholarship from the Ministerio de Education y Ciencia (MEC).

Several subgroups of Cushing's disease were recently described (anterior or intermediate lobe origin, hyper-or hypo-pulsatility of cortisol, presence or absence of response after GRH or TRH, cyclical Cushing's disease). We present here a detailed case report on a patient suffering from Cushing's disease whose endocrine functions were extensively investigated. Treatment with bromocriptine, as well as subsequent transsphenoidal surgery, were followed by rapid but transient reversal of symptoms. When clinical manifestations reoccurred, daily measurements of free urinary cortisol revealed a cyclic pattern of cortisol hyperexcretion. A study of ultradian rhythm revealed hyperpulsatility of cortisol secretion. More interestingly, a treatment with sodium valproate, a drug known to inhibit CRH production, was followed by a rapid and longstanding normalization of clinical and biological data for 2 years. Based on these data, and on information from the literature, the present case of Cushing's disease exhibits characteristics suggesting a possible hypothalamic origin.

This study was conducted to describe the minimum detection limit, reproducibility, accuracy, specificity and parallelism of different pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA) systems: RIA-497, RIA-706, RIA-780, RIA-809 and RIA-Pool. Their ability to distinguish between non-pregnant and pregnant females at day 30 after artificial insemination (AI) was investigated. The antisera were raised in rabbits against different PAG preparations. All RIA systems proved to be sensitive, repeatable and accurate for measuring PAG concentrations. The dilutions of plasma samples taken at an early stage of pregnancy were found to be parallel to the standard curves. No cross-reaction was observed with different carbohydrates, either with Pregnant Mare Serum Gonadotropin (PMSG) or human Chorionic Gonadotropin (hCG). The concentrations of PAG in pregnant females at day 30 after AI were shown to be higher with the use of antisera R#706, R#780, R#809 and Pool when compared with antiserum R#497. All the RIA systems gave 100% sensitivity and negative predictive values. On the other hand, the use of antisera R#780 and R#809 resulted in lower specificity and positive predictive values. The present study clearly shows that the ability of PAG-RIA systems to diagnose pregnancy specifically at day 30 after AI can be improved by using a combination of antisera raised against different forms of PAG.

Contents This study describes ovine pregnancy-associated glycoprotein (ovPAG) concentrations in 20 Lacaune sheep during early pregnancy. Measurements were performed by using semi-purified ovPAG as standard, tracer and immunogens for antibody production in rabbits. Antisera R780 (against ovPAG57+59kDa) and R805 (against ovPAG558+61kDa) were used respectively in RIA-780 and RIA-805. Blood samples were collected at days 0, 18, 20, 22 and 25 after artificial insemination. From day 18 after breeding onward, the mean ovPAG concentration was significantly higher (p

The aims of the present study were to evaluate and compare the accuracy of transrectal ultrasonography and pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA) test for diagnosis of pregnancy in buffaloes. Two hundred and seventy-five buffalo cows and heifers were examined once for pregnancy diagnosis by transrectal ultrasonography using a 5 MHz linear-array transducer between Days 19 and 55 after mating. After ultrasound scanning, a blood sample was withdrawn from jugular vein of each animal for measuring pregnancy-associated glycoprotein using a heterologous double-antibody RIA. Based on palpation of the uterus per rectum at Days 75-90, 87 animals were designated pregnant and 188 as non-pregnant. The sensitivity of transrectal ultrasonography at Days 19-24 was 44.4%, reaching 100% from Day 31 after mating. The specificity of transrectal ultrasonography ranged between 92.5 and 100% from Days 19 to 55 after mating. The sensitivity of PAG-RIA test was 11.1% at Days 19-24 and reached 100% from Day 31 after mating. The specificity of PAG-RIA test ranged from 90 to 100% from Days 19 to 55 after mating. There were no significant differences between the sensitivity and specificity of the two tests in all examined periods. In conclusion, transrectal ultrasonography and PAG-RIA test are highly accurate tests for detecting pregnant buffaloes from Day 31 after mating onwards.

We sought to determine whether prolactin (PRL) could influence the neutrophilic inflammation that characterizes chronic mastitis. Most of the genes encoding inflammatory proteins depend on the nuclear factor kappaB (NF-kappaB) for their expression. We addressed the hypothesis that immunomodulatory activities of PRL might arise from an increase in NF-kappaB activity. MAC-T cells, a bovine mammary epithelial cell line, were stimulated with increasing concentrations of bovine PRL (1, 5, 25, 125, and 1,000 ng/mL). Level of NF-kappaB binding activity was measured and mRNA was evaluated for IL-1beta, IL-6, IL-8, granulocyte-macrophage colony-stimulating factor (GMCSF), IFN-gamma, and tumor necrosis factor (TNF)-alpha, cytokines known to require NF-kappaB for their maximal transcription. Prolactin activated NF-kappaB; maximal NF-kappaB activation was weaker with PRL than with TNF-alpha at 30 or 180 min poststimulation. In addition, PRL significantly amplified, in a dose-dependent manner, mRNA expression of IL-1beta, IL-6, IL-8, GMCSF, and TNF-alpha. We measured PRL concentrations in blood and milk from healthy and chronic mastitis-infected cows, and studied the relationship between the PRL concentration and the degree of inflammation in the mammary gland as indirectly assessed by somatic cell counts (SCC). Plasma PRL did not differ significantly between healthy and chronic mastitis-affected cows (63.7 and 67.5 ng/mL, respectively). Milk PRL concentration was significantly increased in chronic mastitis-affected quarters with the highest SCC, and had a positive significant correlation between SCC, as well as between the number of neutrophils present in milk samples. The present findings show that PRL promotes an inflammatory response in bovine mammary epithelial cells via NF-kappaB activation, and suggest a role for PRL in the pathogenesis of chronic mastitis.

Lactating dairy cows with a mature corpus luteum (CL) (diameter of >/=17 mm determined by ultrasonography) and having a follicle with a diameter of 10 mm (n = 49) were randomly assigned to three groups. The first group was treated with a single dose of exogenous prostaglandin (25 mg), while the second group was treated with 35 mg on day 0, and the third group served as control in order to evaluate the effect of rectal manipulation on the CL during ultrasonographic examination. Blood samples were collected daily for analysing progesterone (P4) concentrations. In group 1 the incidence of oestrus and artificial insemination (AI) in 10 days after treatment was 95% (19 of 20). The conception rate was 31.6%, and the average time to oestrus after treatment was 3.7 day. In group 2 the incidence of oestrus and A.I. was 84.2% (16/19). The conception rate was 31.2%, and the average time to oestrus after treatment was 2.8 day. In the untreated group only two cows (2/10) exhibited oestrus during the examined period and none of them became pregnant. There were no significant differences between the two treated groups in terms of reduction in the area of CL and P4 concentrations and of an increase in the area of the dominant follicles. At the same time, the decrease in the percentage changes relative to the area of CL and to the concentrations of P4 were statistically significant in both treated groups.

Thirty-six West African Dwarf (WAD) goats were used to assess the effects of an experimental Trypanosoma congolense infection on their reproductive system. Estrous cycles were synchronised and when confirmed pregnant (n = 31), the does were randomly allocated into control and trypanosome-infected groups. After infection, the animals were carefully observed till parturition. Trypanosome infection caused an increase of rectal temperature, a significant drop in PCV (infected: 23.3 +/- 0.3%; control: 28.5 +/- 0.4%; P < 0.0001) and abortions in 27.8% of the infected does. Kids born from infected does had a lower birth weight than kids born from control goats (0.9 +/- 0.1 kg versus 1.6 +/- 0.1 kg; P < 0.0001). Eight out of 13 kids (61.5%) that were born alive from infected does died during their first week of life. Plasma pregnancy-associated glycoprotein (PAG) and progesterone concentrations were lower in the infected animals than in the controls. In general, PAG concentration in does which aborted dropped before abortion. Our results revealed that artificial T. congolense infection affected reproductive performance of WAD goats with abortions, premature births and perinatal losses being observed. Neither transplacental transmission of T. congolense nor histopathological lesions of the placenta could be demonstrated.

Pregnancy-associated glycoproteins (PAGs) constitute a large family of glycoproteins that are synthesized in the superficial layer of the ruminant placenta according to a spatial and temporal expression pattern. When PAGs are released in the maternal blood they can be used for pregnancy diagnosis, pregnancy follow-up and for the monitoring of the trophoblastic function. Three different radioimmunoassay systems (RIA 1, RIA 2 and RIA 3) using antisera produced against PAG I67 (RIA 1), PAG55+62 (RIA 2) and PAG55+59 (RIA 3) were used in this investigation in order to measure the PAG concentration in plasma samples withdrawn from pregnant cows and heifers during different periods following artificial insemination (AI). These systems were able to detect PAG molecules in the maternal blood as early as 21 days after AI in different concentrations (RIA 1: 0.43 +/- 0.24 ng/ml, mean +/- SD; RIA 2: 0.48 +/- 0.24 ng/ml; RIA 3: 0.64 +/- 0.37 ng/ml). On days 32 and 42 RIA 2 (4.30 +/- 1.32 ng/ml and 5.56 +/- 1.95 ng/ml) and RIA 3 (4.17 +/- 1.15 ng/ml and 5.60 +/- 1.89 ng/ml) presented significantly (p0.0001) higher PAG concentrations than those of RIA 1 (2.43 +/- 0.81 ng/ml and 4.01 +/- 1.48 ng/ml), respectively. After day 21, significant correlations (p0.0001; r/= 0.929) were determined between the three systems. Additionally the three individual PAG profiles presented in this study showed that PAG molecules secreted in the maternal blood between 21 and 50 days after AI were better recognized by the RIA 2 and RIA 3 systems. This study clearly indicated that the ability of a RIA test to recognize PAG molecules in the maternal blood can be improved by carefully selecting the antiserum.

In ruminants, glycoproteins synthesized in the outer layers of the trophoblast enter the maternal bloodstream. The assay of their concentration in plasma or in serum can be used for pregnancy diagnosis and to indicate feto-placental health status. In this study, concentrations of the pregnancy-associated glycoprotein (PAG) were investigated in the milk of dairy goats. The mean concentrations of PAG in milk were significantly higher in pregnant than in non-pregnant goats throughout the sampling period. Positive milk PAG levels were found in all pregnant animals from Day 32 after breeding, but remained at negative values in nonpregnant ones. This study reports for the first time a pregnancy diagnosis based on milk concentrations of PAG, that could be of great use on the farm.

The pregnancy-associated glycoprotein (PAG) concentration profiles of goats that had been experimentally inoculated with either Toxoplasma gondii or Listeria monocytogenes are described. All goats were examined regularly by ultrasonography. In T. gondii-infected females (n = 5), a slow decrease of PAG was observed throughout a period of 55 to 74 d after inoculation. Afterwards, the goats either aborted (n = 4) or kidded 1 dead and 1 weak fetus (n = 1). In L. monocytogenes-infected females (n = 8), a marked decrease of PAG was observed from the day of inoculation. Abortion occurred within 9 to 11 d post inoculation (n = 7). Only 1 goat kidded a healthy fetus.

At Days 26 to 58 after AI, 138 Holstein-Friesian dairy cows were repeatedly examined by ultrasonography, using a 7.5 MHz linear-array rectal transducer. The total calving rate was 37.6% (52/138), and late embryonic mortality occurred 8.6% of the cows (12/138). On the days of ultrasound scanning, blood samples were drawn from the jugular vein for measuring the concentration of bovine pregnancy-specific protein B (bPSPB) and bovine pregnancy-associated glycoprotein 1 (bPAG 1). When compared with calving results, there were no significant differences in accurate diagnosis of pregnant cows were found between the 3 methods. However, when recognition of an embryo proper with a beating heart was used as the criterion for positive ultrasonographic diagnosis significantly fewer (P < 0.001) pregnant cows were correctly identified than by the other 2 tests. When compared with the noncalving cows, significantly fewer (P < 0.001) false positive diagnoses were made by the 2 ultrasonographic tests than by the PSPB and bPAG 1 tests, while significantly fewer (P < 0.001) false positive diagnoses were made by the bPSPB test than by the bPAG 1 test. The accuracy of detecting nonpregnant animals by both protein tests was limited by the relatively long half-life of these proteins after calving and by early embryonic mortality.

Different RIA systems available for measuring the concentrations of pregnancy-associated glycoproteins (PAGs) in dairy goats were compared in order to evaluate their accuracy in early pregnancy diagnosis. Plasma concentrations of PAGs were determined by 3 heterologous RIA systems with a bovine PAG standard and tracer in combination with antisera anti-ovine PAG (RIA 1), anti-caprine PAG55 + 62 (RIA 2), anti-caprine PAG55 + 59 (RIA 3), and by 2 homologous RIA systems that employed caprine PAG55 + 62 and caprine PAG55 + 59 and their specific antisera (RIAs 4 and 5, respectively). In all of the RIAs, the mean concentrations of PAGs were significantly higher (P0.01) in pregnant than in nonpregnant goats from Day 21 onwards after breeding. On Day 21, the accuracy rates of early pregnancy diagnoses were 56% (RIA 1), 96% (RIA 2), 99% (RIA 3), 95% (RIA 4) and 90% (RIA 5), whereas on Day 28 these rates were99% for RIAs 2, 3, 4 and 5. The RIAs for PAGs depend on proteins from the placenta being present in maternal plasma and require only a single sample of blood, to distinguish pregnant goats from those that fail to return to estrus for other reasons. The homologous and semi-heterologous assays are highly accurate as early as Day 21 of pregnancy.

The effects of ultrafine polystyrene carboxylate-modified (fluorospheres) on inflammatory processes are being investigated in rabbit lungs. One milliliter of sterile NaCl (0.9%) containing 4 mg of ultrafine particles (UFP) was intratracheally instilled into anesthetized rabbits. The control animals were only instilled with sterile NaCl (0.9%). Twenty hours after being instilled, the rabbits were killed and their lungs were excised and then tracheally perfused with phosphate-buffered physiological solution (PBS). The lung effluents, collected from small holes made in the pleura, were analyzed for substance P (SP) and histamine content by radioimmunoassay (RIA) methods, after administration of drugs. In addition, in other groups of rabbits, the lung wet/dry (W/D) weight ratio was monitored, as were the cellular and protein contents in bronchoalveolar lavage (BAL). Electron microscopy examination was also performed. In tracheally superfused experiments, UFP induced a significant enhancement of both SP and histamine releases after administration of capsaicin (10(-4) M), to stimulate C-fiber, and carbachol (10(-4) M), a cholinergic agonist. A significant increase in histamine release was also recorded in the UFP-instilled group following the administration of both SP (10(-6) M) plus thiorphan (10(-5) M) and compound 48/80 (C48/80) (10(-3) M) to stimulate mast cells. In addition, the BAL fluid analysis of UFP groups showed an influx of neutrophils and an increase in total protein concentration. An increase in the lung WW/DW ratio was also recorded. Both epithelial and endothelial injuries were observed in the lungs of UFP-instilled rabbits. The pretreatment of rabbits in vivo with a mixture of either SR 140333 and SR 48368, a tachykinin NK(1) and NK(2) receptor antagonist, or a mixture of terfenadine and cimetidine, a histamine H(1) and H(2) receptor antagonist, prevented UFP- induced neutrophil influx and increased total proteins and lung WW/DW ratio. Therefore, it can be concluded that chemicaly inert, electrically charged UFP induce a pulmonary inflammatory process during which the release of SP and histamine from C-fibers and mast cells was enhanced after various stimuli. These latter mediators can also modulate the inflammatory process.

Between days 27 and 59 after artificial insemination (AI), 189 ultrasonographic pregnancy diagnoses were made in 56 dairy cows using a 7.5 MHz linear-array rectal transducer. Blood samples were withdrawn from a jugular vein on the day of Al, on day 21, and after each ultrasonographic examination between days 27 and 31, days 34 and 38, days 41 and 45 and days 55 and 59 after AI. Plasma concentrations of bovine pregnancy- associated glycoprotein 1 (bPAG-1) were measured by radioimmunoassay. The results showed that before day 31, ultrasonographic scanning was not very sensitive because six of the 30 calving cows were incorrectly diagnosed as non-pregnant. In five of these animals, the uterus was located far cranial to the pelvic inlet. Five of the cows examined between days 27 and 31 were pregnant on the basis of plasma bPAG-1 levels on the same day, using 0.5 ng/ml as the cut-off point. Plasma levels of bPAG-1 and progesterone proved that four of the cows which had early positive ultrasonographic diagnoses but did not produce a calf, were pregnant when they were examined.

This study characterized the peripheral plasma bovine pregnancy-associated glycoprotein (bPAG) profile throughout gestation and examined the effect of stage of gestation and fetal number on this profile in Holstein cows after non-surgical embryo transfer. Cows (n = 12) were divided into three groups: group 1 = normal singleton pregnancies (n = 5); group 2 = normal twin pregnancies (n = 5); group 3 = abnormal twin pregnancies (n = 2). Blood was collected about every third day from day 0 (defined as the first day of standing estrus), then daily for the last 10 days of gestation, and sampling was stopped one day postpartum. The time-related changes in plasma bPAG concentrations were significantly (P < 0.01) affected by the stage of gestation and fetal number (P < 0.01), except during the last 10 days of gestation. In both normal pregnancy groups, bPAG concentration increased rapidly during the first trimester (0.5 +/- 0.1 to 14.6 +/- 1.7 ng/ml and 1.0 +/- 0.6 to 21.8 +/- 4.8 ng/ml, in singleton and twin-bearing groups respectively), then progressively between days 160 and 20 prepartum (31.6 +/- 6.2 to 114.3 +/- 31.3 ng/ml and 41.6 +/- 7.4 to 155.8 +/- 36.6 ng/ml in singleton and twin-bearing cows respectively). The mean concentration between days 20 and 10 prepartum approximately tripled (P < 0.001) in both these groups of cows (114.3 +/- 31.1 to 493.0 +/- 75.3 ng/ml and 155.8 +/- 36.6 to 409.3 +/- 114.7 ng/ml in singleton and twin-bearing cows respectively), but between days 10 prepartum and parturition the values increased about threefold (P < 0.01) in the singleton group (493.0 +/- 75.3 to 1352.8 +/- 286.5 ng/ml) and fivefold (P < 0.001) in the twin-bearing group (409.3 +/- 114.7 to 2154.0 +/- 505.7 ng/ml). The two cows in group 3 that gave birth prematurely to a stillborn calf or to a schistosomus reflexus calf exhibited an aberrant bPAG profile. Our results indicate that peripheral bPAG concentrations are correlated to the stage of gestation and fetal number, and that the profile of the peripheral plasma concentrations provides a useful indication of the feto-placental status.

Quinze vaches zébus Azawak ont été soumises à deux protocoles de synchronisation de l’oestrus. Les concentrations plasmatiques de LH et le pourcentage des femelles ayant exhibé un comportement d’oestrus ont été répertoriés. Le premier traitement de synchronisation (T1, n = 9) a été effectué avec des implants sous-cutanés de norgestomet placés sous la peau de l’oreille pendant 10 jours. Le traitement a été complété par des injections de valérate d’oestradiol, de prostaglandine F2α et de pregnant mare serum gonadotropin (PMSG). Le deuxième protocole (T2, n = 6) a consisté en deux injections de prostaglandine F2α à 11 jours d’intervalle, suivies d’une injection de PMSG deux jours après la deuxième injection de prostaglandine. Des échantillons de sang ont été prélevés à trois heures d’intervalle pendant cinq jours après le retrait de l’implant (T1) ou l’injection de PMSG (T2) pour mesurer les taux de LH. Le taux d’oestrus induit a été plus élevé chez les vaches du groupe T2, mais cette différence n’a pas été significative. En général, le temps observé entre la fin du traitement et le début de l’oestrus a été plus court chez les femelles traitées au norgestomet (35,9 ± 3,9 h) que chez celles traitées à la prostaglandine (49,5 ± 5,8 h). Sept sur les neuf femelles traitées au norgestomet et seulement deux sur les six traitées à la prostaglandine ont présenté un pic de LH. L’intervalle moyen entre la fin des traitements et le pic de LH a eu tendance à être plus long chez les femelles traitées à la prostaglandine que chez celles traitées au norgestomet. Une femelle a présenté des concentrations de LH anormalement élevées après le retrait de l’implant. Toutefois, aucun pic de LH n’a été observé pendant la période de suivi.

Concentrations of bovine placental lactogen (bPL) were determined in fetal plasma samples by twelve double-antibody competitive radioimmunoassay systems (RIA I–XII) based on either recombinant bPL (non-glycosylated) or native bPL (glycosylated). Both preparations were used as standard and tracer, and for primary antisera production. The minimum detection limit measured by these RIA varied from 0.02 to 0.6 ng bPL mL–1. The coefficients of correlation of different bPL RIA systems were up to 90% (P < 0.0001) when each RIA was tested against the average values of all twelve RIA systems. All developed RIA were used to investigate the incidence of different bPL isoforms in bovine fetal serum samples (n = 71). Fetal concentrations ranged from 11.8 to 35.7 ng mL–1 at the third month and from 1.1 to 13.5 ng mL–1 at the ninth month of gestation. They tended to decrease with advancing gestation. In general, those RIA systems that used recombinant bPL as the standard measured higher values than those using the native bPL preparation. These differences decreased toward the end of gestation (P < 0.05), suggesting a lower rate of glycosylation. Our results provide evidence of different glycosylated isoforms of bPL in fetal serum at different gestation periods.

One of the big obstacles in management of reproductive activity in water buffaloes is their silent estrus. This characteristic prevents the determination of time for artificial insemination (AI), resulting in lengthening of the calving interval (Nguyen et al. 1990 Proc. FAO Workshop, Bulgaria, 210–216). Pregnancy-associated glycoprotein (PAG) measurement in maternal blood is an effective method of early pregnancy diagnosis in ruminant species (Zoli et al. 1992 Biol. Reprod. 46, 83–92). The present study describes a preliminary attempt to improve buffalo reproductive performance by association of three different approaches: synchronization of estrus by hormonal treatment, followed by two AI, and finally pregnancy diagnosis based on PAG measurements. A total of 33 buffalo females (4 to 15 years old), with no apparent estrus during a period of 9 to 36 months after last calving, were used. Each female received 2 injections of 5 mL of PGF2α (Intervet, France) 10 days apart (Day −12 and Day −2), one injection of 500 IU of PMSG (SABC, Vietnam) at Day −5, and 1000 IU of hCG (Intervet, France) on the day of AI (Day 0). A second AI was performed 8 h after hCG injection. Blood samples (9 mL) were collected from each female at Days 20, 25, 40, and 45 after AI. Blood samples were withdrawn by jugular venipuncture (heparinized Vacutainer tubes) and kept in a cool box until centrifugation (500g, 10 min). Plasma samples were stored at −20°C until assayed for PAG. Pregnancy diagnosis was considered negative, doubtful, or positive according to the PAG concentrations (0.8 ng mL−1, respectively). Clinical observation of females after insemination showed that the total rate of animals that exhibited signs of estrus until Day 45 was 9.1% (3/33). These 3 females were not considered for pregnancy diagnosis. Table 1 shows the results of pregnancy diagnosis in 30 water buffalo females. These results show that fertilization is easily obtained after estrus synchronization in buffaloes and that measurement of PAG concentrations in maternal plasma can be used for pregnancy diagnosis from Day 40 after AI. Table 1.Number of water buffalo females considered as non-pregnant, doubtful or pregnant on the basis of PAG concentrations This work was supported by a grant from the Belgian Technical Cooperation.

L’objectif de la présente étude a été la caractérisation des profils plasmatiques de la protéine associée à la gestation (PAG) et de la progestérone, au cours de la gravidité et deux semaines après le part chez la race Ouled Djellal. Vingtcinq brebis ont été prélevées hebdomadairement après synchronisation des chaleurs et monte naturelle. Les concentrations de PAG et de progestérone ont été déterminées par dosage radio-immunologique. Deux femelles n’ont pas été fécondées tandis que 23 ont eu des gestations considérées comme normales (n = 18) ou pathologiques (n = 5). Chez 18 brebis (12 gestations simples et 6 multiples), les concentrations de PAG et de progestérone ont été significativement influencées par le stade de la gestation (P < 0,0001) et non par le nombre de foetus. Des profils individuels ont été décrits chez sept brebis, dont trois femelles ayant eu des pertes embryonnaires, et deux brebis ayant avorté (66e et 110e jours), et enfin chez deux brebis ayant donné naissance à terme chacune à un agneau vivant et expulsé au moment de la mise bas un ou deux foetus momifiés. Les concentrations en PAG ont été plus faibles chez les femelles ayant eu des foetus momifiés en parallèle avec des foetus vivants.

Early pregnancy detection and prediction of the number of lambs would be profitable for sheep breeders, as this enables nourishment of pregnant ewes to their individual needs. Nonpregnant ewes can be separated and sold before winter. Prediction of sex is interesting for the curiosity of impatient breeders. Early pregnancy detection (before 45 days after mating) by means of ovine pregnancy-associated glycoproteins (ovPAGs) has proved to be a more reliable test than the commonly used transrectal ultrasound. The concentration of ovPAG has been claimed to be related to the number of lambs, their sex and birth weight, but contradictory results were obtained in different small-scale studies. In this study the correlation between number of lambs, their sex and birth weight and the ovPAG concentration in the serum of the ewes was examined. In a field trial, 160 and 70 ewes of the Texel and Suffolk breed, respectively, housed on 6 different farms, were synchronized by means of intravaginal sponges impregnated with 40mg cronolone (Chronogest®, Intervet, Boxmeer, The Netherlands). At the moment of synchronisation (T0) and at 25 (T25), 35 (T35) and 45 (T45) days after mating or artificial insemination, blood samples were taken by jugular vein puncture. A heterologous radioimmunoassay (RIA) was used to determine the ovPAG concentration. In the heterologous RIA boPAG molecules were used as tracer, and ovPAG molecules as standard, while rabbit antibodies against ovPAG were used as antiserum. At parturition, number, sex and birth weight of the lambs were registered and their effect on ovPAG concentrations was statistically evaluated. No significant difference in ovPAG concentration was found between ewes pregnant of a single male or female lamb (P=0.29). ovPAG concentrations were affected by the total birth weight (P

In sheep, conception rates of 80% are obtained after first mating. Some of the ewes that were not pregnant may have conceived, but underwent embryonic mortality. Embryonic mortality can be distinguished as early (EEM) or late (LEM) embryonic mortality. When EEM occurs, sheep return to estrus 17 ± 2 days after mating, which makes the detection of EEM very difficult. Because determination of ovine pregnancy-associated glycoprotein (ovPAG) concentration can be used for pregnancy diagnosis from Day 25 of conception, with a specificity and sensitivity of 100% and 99%, respectively, it possibly could be used for detection of LEM (Verberckmoes et al., 2003. Pregnancy diagnosis in sheep by means of ultrasound and ovine pregnancy associated glycoproteins (ovPAG), 10th International Symposium on Veterinary Epidemiology and Economics (ISVEE 10), 17–21 November, 2003.). Therefore, in this study the prevalence of LEM and the usefulness of ovPAG concentration for the detection of LEM were examined. In a field trial, serum samples of 160 Texel and 127 Suffolk ewes were collected at the moment of estrus synchronization (T0), and at 25 (T25), 35 (T35), and 45 days (T45) after mating. Concentrations of ovPAG were determined by means of homologous RIA using ovine PAG as standard and tracer, and rabbit antibodies against ovPAG as antiserum. Ewes were considered as being pregnant when ovPAG concentrations were higher than 2 ng mL-1. The F-test in a mixed model with ewe as random effect was used to compare the mean PAG concentrations. Of the 287 ewes examined, 5 Suffolk and 2 Texel ewes showed an abnormal PAG profile which was indicative of LEM. The average ovPAG concentration of the 7 former ewes at T25 was 5.6 ± 2.0 ng mL-1, which indicates that they were pregnant. However, in contrast to the normal pregnant ewes, they had significantly lower ovPAG concentrations at T35 (2.8 ± 1.5 ng mL-1 v. 9.5 ± 2.3 ng mL-1) and T45 (0.9 ± 0.3 ng mL-1 v. 9.0 ± 1.9 ng mL-1) (P

Analysis of blood for a protein associated with pregnancy has been suggested as a reliable alternative to traditional pregnancy tests for deer. However, the accuracy of this technique has not been tested throughout gestation in white-tailed deer (Odocoileus virginianus). In addition, quantification of protein relative to stage of gestation and fetal number has not been reported. To address these needs, sera collected from 6 captive white-tailed does before breeding, throughout gestation, and following parturition were tested by radioimmunoassays (RIA) developed using glycoproteins isolated from domestic cattle and sheep. These RIAs provide the first quantitative pregnancy-associated glycoprotein (PAG) tests for deer. In our study, PAG levels increased throughout pregnancy and declined linearly following parturition. Beyond mid-gestation, PAG levels reflected in utero fetal number. The bovine-PAG (bPAG) assay was 100% accurate beyond day 65 of gestation. The ovine-PAG (oPAG) assay detected pregnancy by mean day 22 of gestation and was 100% accurate beyond day 32. Our oPAG-RIA is the most effective pregnancy test reported for white-tailed deer.

Serum concentrations of testosterone, 5α-dihydrotestosterone, oestradiol and progesterone were measured by radioimmunoassay combined with Celite chromatography in male and female Japanese quail (Coturnix coturnix japonica) during the second half of embryonic life (days 9–17 of incubation) and during the first 5 weeks after hatching. The mean level of each of the four steroids was significantly affected by the age of the birds. An overall effect of sex was detected by analysis of variance only on oestradiol concentrations, with females having higher serum concentrations than males during most of the age range studied. Significant peaks of testosterone and progesterone were also detected around hatching time. These results are consistent with the view that oestradiol is the major hormone implicated in the sexual differentiation of reproductive behaviour in the quail. The relationships between the circulating concentrations of oestradiol during ontogeny and the critical period of differentiation as postulated by currently accepted models is also discussed. J. Endocr. (1988) 118, 127–134

Adult male Japanese quail were transferred from long to short days. Plasma testosterone and dihydrotestosterone quickly decreased and this endocrine response was followed by a regression of the cloacal gland, an androgen-target organ. After about a month, a spontaneous recovery of gonadal activity was observed in some but not all birds. It was not associated with obvious shifts in the circadian system. The physiological bases of this spontaneous recovery are discussed as well as the detailed relationships between plasma testosterone and cloacal gland size.