Fetal Death Associated With Premature Mammary Gland Development and Lactation in a Mare Treated With Weekly Injections of Long-Acting Progesterone.

A 14-year-old, 530-kg, multiparous, pregnant Quarter Horse mare was referred for evaluation of premature mammary gland development and lactation. The mare was in the seventh month of gestation. The mare had a history of subfertility and was receiving weekly injections of long-acting progesterone, prescribed by the referring veterinarian. The last dose had been administered four days before presentation. Upon presentation, the mare had vital signs within normal limits, a moderately developed, nonpainful udder with galactorrhea, and no vulvar discharge. Transrectal palpation revealed a well-toned uterus and cervix and discreetly palpable fetal parts, however, ballottement of the fetus did not result in appreciable fetal movement. Transrectal ultrasound was unremarkable, but transabdominal ultrasound revealed one underdeveloped, immotile fetus in the left uterine horn with no heartbeat. Abortion was induced with repeated doses of cloprostenol. Fifty-four hours after the first cloprostenol injection, the mare displayed signs of labor, the cervix was manually dilated, and the fetus and fetal membranes were expelled with gentle manual manipulation. Standard postabortion care included uterine lavage and oxytocin for 48 hours before being discharged to the care of her owners. Fetal crown-rump length (53 cm) was consistent with a 6-month fetus rather than its gestational age of 7 months. The umbilical cord was edematous, and a distended, fluid-filled structure surrounded the cord at the intersection of the allantoic and amniotic segments of the umbilical cord. This structure was determined to be the severely dilated urachus. Microscopic findings included placental stromal mineralization, distended umbilicus adventitia, and dilated umbilical lymphatics with no other significant findings. Remaining abortion diagnostic tests were unremarkable. The mare recovered well and was discharged to the care of her owner two days after abortion. The following breeding season the mare carried a healthy foal to term.

Splenic development and injury in premature lambs supported by the artificial placenta.

INTRODUCTION: The purpose of this study is to evaluate splenic effects during artificial placenta (AP) support. METHODS: AP lambs (118-121 d, n = 14) were delivered and placed on the AP support for a goal of 10-14 days. Cannulation used right jugular drainage and umbilical vein reinfusion. Early (ETC; 115-120 d; n = 7) and late (LTC; 125-131 d; n = 7) tissue controls were delivered and immediately sacrificed. Spleens were formalin fixed, H&E stained, and graded for injury, response to inflammation, and extramedullary hematopoiesis (EMH). CD68 and CD163 stains were used to assess for macrophage activation and density. Clinical variables were correlated with splenic scores. Groups were compared using Fisher's Exact Test and descriptive statistics. p < 0.05 indicated significance. RESULTS: Mean survival for AP lambs was 12 ±â€¯5 d. There was no necrosis found in any of the groups. Vascular congestion and sinusoidal histiocytosis did not significantly differ between AP and control groups (p = 0.72; p = 0.311). There were significantly more pigmented macrophages (p = 0.008), CD163 (p = <0.001), and CD68 (p = <0.001) stained cells in the AP group. ETC and LTC demonstrated more EMH than AP spleens (p = <0.001). CONCLUSIONS: During AP support, spleens appear to develop normally and exhibit an appropriate inflammatory response. After initiation of AP support, EMH transitions away from the spleen. STUDY TYPE: Research Paper/Therapeutic Potential. LEVEL OF EVIDENCE: N/A.

Stable Control of Physiological Parameters, But Not Infection, in Preterm Lambs Maintained on Ex Vivo Uterine Environment Therapy.

Ex vivo uterine environment (EVE) therapy is an experimental neonatal intensive care strategy wherein gas exchange is performed by membranous oxygenators attached to the umbilical vessels. Our aim was to assess the ability of a newly refined EVE system to maintain key physiological parameters in preterm lambs within optimal ranges for 48 h. EVE group; n = 6: Preterm lambs were delivered under general anesthesia at 115 ± 2 days of gestational age. Animals were submerged in a bath of artificial amniotic fluid on EVE therapy for 48 h. Physiological parameters were monitored in real-time over the length of the experiment. Control group; n = 11: Ewes carrying a single fetus (115 ± 2 days of gestational age) underwent recovery surgery to allow placement of a fetal carotid artery catheter. Fetuses received an infusion of sterile saline only. After euthanasia, EVE and Control group fetuses underwent necroscopy to perform static pressure-volume curves and for sampling of lung and cord blood plasma for molecular analyses. Five out of six fetuses in the EVE group completed the study period with key physiological variables remaining within their respective reference ranges for the duration of the 48 h study. Bacteremia was identified in four out of five EVE fetuses, and was associated with a systemic inflammatory response. Using our refined EVE therapy platform, preterm lambs were maintained in a stable physiological condition for 48 h. These findings represent a significant advance over earlier work with this system; however, the identification of bacteremia and a fetal inflammatory response suggests that further refinement to the EVE therapy platform is required.

Provision of Amniotic Fluid During Parenteral Nutrition Increases Weight Gain With Limited Effects on Gut Structure, Function, Immunity, and Microbiology in Newborn Preterm Pigs.

BACKGROUND: Small enteral boluses with human milk may reduce the risk of subsequent feeding intolerance and necrotizing enterocolitis in preterm infants receiving parenteral nutrition (PN). We hypothesized that feeding amniotic fluid, the natural enteral diet of the mammalian fetus, will have similar effects and improve growth and gastrointestinal (GI) maturation in preterm neonates receiving PN, prior to the transition to milk feeding. MATERIALS AND METHODS: Twenty-seven pigs, delivered by cesarean section at ~90% of gestation, were provided with PN and also fed boluses with amniotic fluid (AF; n = 13, 24-72 mL/kg/d) or no oral supplements (nil per os [NPO]; n = 14) until day 5 when blood, tissue, and fecal samples were collected for analyses. RESULTS: Body weight gain was 2.7-fold higher in AF vs NPO pigs. AF pigs showed slower gastric emptying, reduced meal-induced release of gastric inhibitory peptide and glucagon-like peptide 2, changed gut microbiota, and reduced intestinal permeability. There were no effects on GI weight, percentage mucosa, villus height, plasma citrulline, hexose absorptive capacity, and digestive enzymes. Intestinal interleukin (IL)-1ß levels and expression of IL1B and IL8 were increased in AF pigs, while blood biochemistry and amino acid levels were minimally affected. CONCLUSION: Enteral boluses of AF were well tolerated in the first 5 days of life in preterm pigs receiving PN. Enteral provision of AF before the initiation of milk feeding may stimulate body growth and improve hydration in preterm infants receiving PN. Furthermore, it may improve GI motility and integrity, although most markers of GI maturation remain unchanged.

Gestational age at initial exposure to in utero inflammation influences the extent of diaphragm dysfunction in preterm lambs.

BACKGROUND AND OBJECTIVE: In utero infection may critically influence diaphragm development and predispose preterm infants to postnatal respiratory failure. We aimed to determine how frequency and gestational age (GA) at time of intra-amniotic (IA) lipopolysaccharide (LPS) exposure affects preterm diaphragm function. METHODS: Pregnant ewes received IA injections of saline or 10-mg LPS at 7 days or 21 days or weekly injections 21, 14 and 7 days before delivery at 121-day GA. Foetal lambs were killed with pentobarbitone (150 mg/kg; intravenous). Diaphragm contractile function was measured in vitro. Muscle fibre type, activation of protein synthesis and degradation pathways, pro-inflammatory signalling and oxidative stress were evaluated using immunofluorescence staining, RT-qPCR, ELISA, Western blotting and biochemical assay. RESULTS: In utero LPS exposure significantly impaired diaphragm contractile function. LPS exposure 7 days before delivery caused maximum specific twitch and tetanic forces 30% lower than controls. When the initial LPS exposure occurred 21 days before delivery maximum specific forces were 40% lower than controls. Earlier LPS exposure also prolonged twitch contraction time, increased fatigue resistance and elevated protein carbonyl content. Despite increased white blood cell counts and interleukin-6 mRNA expression following weekly LPS exposure, there were no significant differences in contractile properties between exposure 21 days before delivery and repeated LPS groups suggesting that frequency of inflammatory exposure does not influence the severity of contractile dysfunction. CONCLUSIONS: GA at time of initial LPS exposure, rather than frequency of exposure, determines the extent of inflammation-induced diaphragm dysfunction.

Protective ventilation of preterm lambs exposed to acute chorioamnionitis does not reduce ventilation-induced lung or brain injury.

BACKGROUND: The onset of mechanical ventilation is a critical time for the initiation of cerebral white matter (WM) injury in preterm neonates, particularly if they are inadvertently exposed to high tidal volumes (VT) in the delivery room. Protective ventilation strategies at birth reduce ventilation-induced lung and brain inflammation and injury, however its efficacy in a compromised newborn is not known. Chorioamnionitis is a common antecedent of preterm birth, and increases the risk and severity of WM injury. We investigated the effects of high VT ventilation, after chorioamnionitis, on preterm lung and WM inflammation and injury, and whether a protective ventilation strategy could mitigate the response. METHODS: Pregnant ewes (n = 18) received intra-amniotic lipopolysaccharide (LPS) 2 days before delivery, instrumentation and ventilation at 127±1 days gestation. Lambs were either immediately euthanased and used as unventilated controls (LPSUVC; n = 6), or were ventilated using an injurious high VT strategy (LPSINJ; n = 5) or a protective ventilation strategy (LPSPROT; n = 7) for a total of 90 min. Mean arterial pressure, heart rate and cerebral haemodynamics and oxygenation were measured continuously. Lungs and brains underwent molecular and histological assessment of inflammation and injury. RESULTS: LPSINJ lambs had poorer oxygenation than LPSPROT lambs. Ventilation requirements and cardiopulmonary and systemic haemodynamics were not different between ventilation strategies. Compared to unventilated lambs, LPSINJ and LPSPROT lambs had increases in pro-inflammatory cytokine expression within the lungs and brain, and increased astrogliosis (p<0.02) and cell death (p<0.05) in the WM, which were equivalent in magnitude between groups. CONCLUSIONS: Ventilation after acute chorioamnionitis, irrespective of strategy used, increases haemodynamic instability and lung and cerebral inflammation and injury. Mechanical ventilation is a potential contributor to WM injury in infants exposed to chorioamnionitis.

Congenital ascites due to hepatoblastoma with extensive peritoneal implantation metastases in a premature equine fetus.

A premature dead equine fetus with excessive fluctuating distension of the abdomen was delivered by extraction. Post-mortem examination revealed ascites and a solitary, irregular, bulging, multinodular, firm, yellow mass of 25 cm in diameter in the right liver lobe. Extensive peritoneal implantation metastases were present. The masses were composed of polygonal embryonal cells arranged in sheets and nests. Based on the immunohistochemical expression of Ki67, low molecular weight cytokeratin and alpha-1 fetoprotein, a diagnosis of hepatoblastoma with peritoneal implantation metastases was made.

Long-term pulmonary effects of intrauterine exposure to endotoxin following preterm birth in sheep.

Our aim was to determine whether fetal exposure to intraamniotic lipopolysaccharide (LPS) persistently alters the lungs following moderate preterm birth. Fetal sheep were exposed to LPS (1 mg/d) or saline from 0.75 to preterm birth at 0.90 of gestation. Eleven weeks after preterm birth, lung structure was unaltered. Interleukin (IL)-1ß messenger RNA (mRNA) levels were elevated in lungs of LPS-exposed lambs (P < .05) but IL-1ß protein levels were unaltered. Lung mRNA levels of IL-6, IL-8 and tumor necrosis factor α, and percentage of inflammatory cells were not different between groups. Surfactant protein (SP)-A and SP-C mRNA levels and SP-B tissue protein expression were higher in LPS-exposed lambs than controls (all P < .05); however, expression of SP-A and SP-C proteins was reduced. Prenatal LPS exposure causes a persistent increase in gene expression of proinflammatory mediators and surfactant proteins and a decrease in lung tissue SP-A and -C protein expression after preterm birth, which may affect lung immunity.

Relationship between infection, inflammation and premature parturition in mares with experimentally induced placentitis.

REASONS FOR PERFORMING THE STUDY: Ascending placentitis results in premature birth and high foal mortality. By understanding how placentitis induces premature delivery, it may be possible to develop diagnostic markers and to delay premature delivery pharmacologically, thereby decreasing perinatal foal mortality. OBJECTIVE: To identify relationships between bacterial infection, inflammation and premature parturition in mares with experimentally induced placentitis. MATERIALS AND METHODS: Experiment 1: Concentrations of allantoic fluid prostaglandins (PGs) F2alpha and E2 were measured in 8 mares after intracervical inoculation with Streptococcus equi ssp. zooepidemicus (at Days 285-291 of gestation) until parturition and compared with controls (n = 4). Experiment 2: mRNA expression of interleukin (IL)-1beta, IL-6, tumour necrosis factor (TNF)-alpha and IL-8 in the chorioallantois from inoculated mares in Experiment 1 were compared with 7 mares that foaled normally. RESULTS: Bacterial inoculation resulted in 7 aborted fetuses and birth of one premature, viable foal. Infection was associated with inflammation of the chorioallantois in the region of the cervical star, isolation of bacteria and high concentrations of PGE2 and PGF2alpha in allantoic fluid obtained within 48 h of delivery (P = 0.04). Chorioallantois from all mares expressed mRNA for IL-8, TNF-alpha, IL-6 and IL-1beta. Experimentally infected mares expressed more mRNA for IL-6 (P = 0.003) and IL-8 (P = 0.009) in the cervical star region and more mRNA for IL-6 (P = 0.004) in tissues from placental horns than control mares. CONCLUSIONS AND CLINICAL RELEVANCE: Bacterial placentitis may result in liberation of cytokines from the chorioallantois and prostaglandin formation leading to abortion or birth of a precociously mature foal.

The cardiopulmonary haemodynamic transition at birth is not different between male and female preterm lambs.

Males born preterm are at greater risk of illness and death than females, principally due to respiratory disease. Much of the excess morbidity occurs within the first few hours of life. Therefore, the aim of the present study was to investigate whether or not differences in the cardiopulmonary transition soon after birth underlie the increased morbidity in males after preterm birth. Nine female and thirteen male lambs (128±2 days gestation) underwent surgery immediately before delivery for implantation of a pulmonary arterial flow-probe and catheters into the main pulmonary artery and a carotid artery. After birth lambs were ventilated for 30 min (tidal volume 7 mL kg(-1)) while anaesthetised. Arterial pressures and flows were recorded in real time and left-ventricular output measured using Doppler echocardiography. Before birth, fetal cardiopulmonary haemodynamics, arterial blood gases, pH, glucose and lactate did not differ between sexes. Similarly, in the neonatal period there were no significant differences in arterial blood gas status, ventilation parameters, respiratory indices or cardiopulmonary haemodynamics between the sexes. Our data show that the cardiopulmonary transition at birth in ventilated, anaesthetised preterm lambs is not influenced by sex. Thus, the neonatal 'male disadvantage' is not explained by an impaired cardiovascular transition at birth.

Inflammation of the fetal ovine skin following in utero exposure to Ureaplasma parvum.

There is increasing evidence linking in utero infection and inflammation to preterm birth. Many commensal urogenital tract microorganisms, including the Mycoplasmas and Ureaplasmas, are commonly detected in association with preterm birth. Using an ovine model of sterile fetal inflammation, we demonstrated previously that the fetal skin generates a robust inflammatory response following in utero exposure to lipopolysaccharides from Escherichia coli. The fetal skin's response to colonization of the amniotic fluid by viable microorganisms remains unstudied. We hypothesised that in utero infection with Ureaplasma parvum serovar 3 would induce a proinflammatory response in the fetal skin. We found that (1) cultured fetal keratinocytes (the primary cellular constituent of the epidermis) respond to U. parvum exposure in vitro by increasing the expression of the chemotactant monocyte chemoattractant protein 1 (MCP-1) but not interleukin 1ß (IL-1ß), IL-6, IL-8, or tumor necrosis factor-α (TNF-α); (2) the fetal skin's response to 7 days of U. parvum exposure is characterized by elevated expression of MCP-1, TNF-α, and IL-10; and (3) the magnitude of inflammatory cytokine/chemokine expression in the fetal skin is dependent on the duration of U parvum exposure. These novel findings provide further support for the role of the fetal skin in the development of fetal inflammation and the preterm birth that may follow.

Bovine colostrum is superior to enriched formulas in stimulating intestinal function and necrotising enterocolitis resistance in preterm pigs.

Milk contains immunomodulatory compounds that may be important to protect the immature intestine in preterm neonates from harmful inflammatory reactions involved in disorders like necrotising enterocolitis (NEC). We hypothesised that bovine colostrum and milk formulas enriched with sialic acids (SL), gangliosides (Gang) or osteopontin (OPN) would improve gastrointestinal function and NEC resistance in preterm neonates. Forty-seven caesarean-delivered preterm pigs were given total parenteral nutrition for 2 d followed by 1·5 d of enteral feeding. In Expt 1, a control formula was compared with an OPN-enriched formula (n 13), while Expt 2 compared a control formula with bovine colostrum or formulas enriched with Gang or SL (n 4-6). OPN enrichment decreased NEC severity relative to control formula (P < 0·01), without any significant effects on NEC incidence, digestive enzyme activities and hexose absorption. Neither SL- nor Gang-enriched formulas improved NEC resistance or digestive functions, while all the intestinal functional parameters were significantly improved in pigs fed bovine colostrum, relative to formula. The effects in vivo were supported in vitro by bacteria- and dose-dependent modulation by colostrum whey of the cytokine response from bacteria-stimulated murine bone marrow-derived dendritic cells (DC). In conclusion, OPN had only moderate NEC-protective effects, while formulas enriched with Gang or SL were ineffective. The observed modulation of DC cytokine response by bovine colostrum whey in vitro may be due to a synergistic action of various milk bioactives, and it may explain its beneficial effects on NEC development and intestinal function in a piglet model of preterm infants.

Ascending placentitis in the mare: an update.

CONTENTS: Ascending placentitis is a common cause of premature birth, abortion and delivery of compromised, ill foals. Recent experimental models have investigated diagnostic procedures and treatment strategies in an attempt to improve live foal rate. Diagnostics such as transrectal and transabdominal ultrasonography are used to evaluate foetal well-being and placental separation, while measurement of plasma progestins or oestrogen identifies a stressed or hypoxic foetus. Treatment is directed at stopping spread of infection, maintaining uterine quiescence and blocking production of pro-inflammatory cytokines. It must be instituted early if a pregnancy is to be saved. Treatments include antibiotics, tocolytics and immunomodulators. Prompt, aggressive treatment with antibiotics has improved foal viability in experimental models of placentitis.

Pulmonary vascular and alveolar development in preterm lambs chronically colonized with Ureaplasma parvum.

Ureaplasma species, the most commonly isolated microorganisms in women with chorioamnionitis, are associated with preterm delivery. Chorioamnionitis increases the risk and severity of bronchopulmonary dysplasia and persistent pulmonary hypertension in newborns. It is not known whether the timing of exposure to inflammation in utero is an important contributor to the pathogenesis of bronchopulmonary dysplasia. We hypothesized that chronic inflammation would alter the pulmonary air space and vascular development after 70 days of exposure to infection. Pregnant ewes were given intra-amniotic injection of Ureaplasma parvum serovars 3 or 6 at low (2 x 10(4) cfu) or high doses (2 x 10(7) cfu) or media (controls) at 55 days gestational age. Fetuses were delivered at 125 days (term = 150 days). U. parvum was grown from the lungs of all exposed fetuses, and neutrophils and monocytes were increased in the air spaces. Lung mRNA expression of IL-1beta and IL-8, but not IL-6, was modestly increased in U. parvum-exposed fetuses. U. parvum exposure increased surfactant and improved lung gas volumes. The changes in lung inflammation and maturation were independent of serovar or dose. Exposure to U. parvum did not change multiple indices of air space or vascular development. Parenchymal elastin and collagen content were similar between groups. Expression of several endothelial proteins and pulmonary resistance arteriolar media thickness were also not different between groups. We conclude that chronic exposure to U. parvum does not cause sustained effects on air space or vascular development in premature lambs.

Chronic fetal and maternal instrumentation in pregnant sheep: effect on gestation length and birthweight.

The objective was to compare gestation length in chronically instrumented (laboratory) pregnant sheep (n = 131) and in the breeding flock (n = 476) that provided the experimental sheep. In the breeding flock, gestation length was normally distributed and varied between 141 and 151 days (mean = 147 +/- 0.1 days). In the laboratory sheep, gestation length varied between 128 and 151 days (mean = 142 +/- 1 day), and was bimodal, with 35.9% delivering preterm (<141 days). To examine potential factors that contributed to the preterm birth, a severity score was used, which comprised surgery characteristics, number of experiments and maternal or fetal complications. There was a significant inverse linear relationship (P < 0.001) between the total severity score and gestation length. The median values for the surgical (15 v. 12), overall complication (6 v. 2), maternal complication (2 v. 0) and fetal complication (2 v. 2) components were significantly greater in the preterm compared with the term groups. There was no relationship between fetal number and gestation length in either group. It is concluded that in chronic pregnant sheep preparations, there is a significant incidence of preterm birth and that this is associated with the severity of the surgical intervention and with several maternal and fetal complications.

Management of neonatal llamas and alpacas.

Most llama and alpaca crias will be born without complication and survive the neonatal period without incident. However, it is important to be able to recognize which crias are likely to be at risk of complications so that you are best able to advise owners and take the correct course of action if required. This article deals with management of the pregnant camelid, the events associated with parturition and the peripartum period with emphasis on the cria, management of the newborn cria including assessment of passive transfer of immunity, issues relating to prematurity, and the major congenital defects that may present as emergencies within the neonatal period.

Hormone profiles and treatments in the late pregnant mare.

Evaluation of hormone profiles in late pregnancy is one of the major determinants of fetoplacental compromise in equine clinical practice. Use of hormone therapies is subjective and reflects, to a large extent, our lack of understanding about the endocrine relations between the mare, placenta, and fetus. This article describes the normal endocrine events in late gestation, the abnormal hormone patterns associated with fetoplacental dysfunction, and the hormone interventions that are currently used or could be used to improve pregnancy outcome.

Differential expression of ovine innate immune genes by preterm and neonatal lung epithelia infected with respiratory syncytial virus.

Preterm infants have increased susceptibility to severe manifestations of respiratory syncytial virus (RSV) infection. The cause(s) for this age-dependent vulnerability is/are not well-defined, but alterations in innate immune products have been implicated. In sheep, RSV disease severity has similar age-dependent characteristics and sheep have several related innate molecules for study during pulmonary infection including surfactant protein A (SP-A), surfactant protein D (SP-D), sheep beta defensin 1 (SBD1), monocyte chemotactic protein 1 (MCP1), and Toll-like receptor 4 (TLR4). However, the in vivo cellular gene expression as a response to RSV infection is poorly understood. In this study, the effect of RSV infection on expression of these innate immune genes was determined for bovine RSV-infected (bRSV+ fluorescence) epithelial cells, adjacent cells lacking bRSV antigen (adjoining cells lacking fluorescence), and control cells from non-infected lung using laser capture microdissection (LCM) and real-time RT-PCR. Control lambs had increased expression of innate immune molecules in full term (term) compared to preterm epithelia with statistical significance in SBD1, SP-D, and TLR4 mRNA. Infected cells (bRSV+ fluorescent cells) had consistently higher mRNA levels of SP-A (preterm and term), MCP1 (preterm and term), and SP-D (preterm). Interestingly, bRSV- cells of infected term lambs had significantly reduced SP-D mRNA expression compared to bRSV+ and control epithelia, suggesting that RSV infected cells may regulate the adjacent epithelial SP-D expression. This study defines specific innate immune components (e.g., SBD1, SP-D, and TLR4) that have differential age-dependent expression in the airway epithelia. Furthermore, cellular bRSV infection enhanced certain innate immune components while suppressing adjacent cellular SP-D expression in term animals. These in vivo gene expression results provide a framework for future studies on age-dependent susceptibility to RSV and RSV pathogenesis.

Effects of an experimental Trypanosoma congolense infection on the reproductive performance of West African Dwarf goats.

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.