Development of bovine embryos derived from reproductive techniques.

Assisted reproduction techniques have improved agricultural breeding in the bovine. However, important development steps may differ from the situation in vivo and there is a high mortality rate during the first trimester of gestation. To better understand these events, we investigated the development of embryos and fetal membranes following fixed-time AI (FTAI), IVF and nuclear transfer (NT). The onset of yolk-sac development was not normal in cloned embryos. Later steps differed from conditions in vivo in all three groups; the yolk-sac was yellowish and juxtaposed with the amniotic membrane. Vascularisation of the chorioallantoic membrane was relatively late and low in NT gestations, but normal in the others. The overall development of the embryos was normal, as indicated by morphology and regression analysis of growth rate. However, NT conceptuses were significantly smaller, with the livers in some embryos occupying the abdominal cavity and others exhibiting heart abnormalities. In conclusion, the yolk-sac and the cardiovascular system seem to be vulnerable to morphogenetic alterations. Future studies will focus on gene expression and early vascularisation processes to investigate whether these changes may be responsible for the high incidence of intrauterine mortality, especially in clones.

Reproductive parameters following a PRRS outbreak where a whole-herd PRRS MLV vaccination strategy was instituted post-outbreak.

This study assessed the effect of whole-herd porcine reproductive and respiratory syndrome (PRRS) modified-live virus (MLV) vaccination on herd-level reproductive performance, PRRS virus (PRRSV) viremia, and antibody in a subset of females in a 1,200-sow commercial herd in Thailand. Following a PRRSV outbreak, the entire herd was vaccinated with PRRS MLV twice at 3-week intervals and at 3-month intervals, thereafter. Reproductive performance data over a 3-year period were available for analysis. Serum samples were collected before and after vaccination and tested by PRRSV ELISA and reverse transcription-polymerase chain reaction. Vaccination was statistically associated with a lower abortion rate (1.4 vs. 1.6 %), farrowing rate (83.8 vs. 90.0 %), total born (10.6 vs. 11.4 piglets/litter), liveborn (10.0 vs. 10.3 piglets/litter), stillbirths (4.6 vs. 7.0 %), mummies (0.7 vs. 1.6 %), and a higher return rate (11.3 vs. 5.9 %) when compared with the period before the PRRSV outbreak. Pregnant females vaccinated during early gestation farrowed fewer liveborn and more mummies than the comparison group, whereas females vaccinated during late gestation had a lower farrowing rate. In this herd, PRRS whole-herd vaccination had neutral, positive, and negative effects on reproductive performance. Thus, the decision to implement whole-herd vaccination should be balanced between the benefits derived from reproductive performance improvements, e.g., fewer abortions, stillborn piglets, and mummified fetuses, and the effect of vaccination on pregnant females.

Delayed postpartum fetotomy in an Asian elephant (Elephas maximus).

A 37-yr-old Asian elephant (Elephas maximus) started parturition after 640 days of pregnancy but no fetal parts entered the birth canal. Despite veterinary intervention, the calf was not delivered. After 13 mo calving resumed and a full-term dead calf advanced into and lodged within the vagina. With standing xylazine tranquilization, the dam received a vagino-vestibulotomy to permit total fetotomy of the calf, which presented with bilateral carpal arthrogryposis. Severe infection of the caudal vaginal vestibulum complicated wound healing, and over the following year two corrective surgeries were performed, which resolved the fistula 3 mo after the second debridement. The elephant not only survived the procedures but also resumed normal estrous cycles, as demonstrated by blood progesterone concentration monitoring.

Intrauterine fetal death with subsequent quill exfoliation and dissemination in a North American porcupine (Erethizon dorsatum).

An adult female, wild North American porcupine (Erethizon dorsatum) presented with bilateral cataracts and naso-ocular discharge. A pregnancy was identified by radiography with a near-full-term fetus, which was delivered stillborn 4 wk later with hard, developed quills. At that time, a repeated examination and further imaging, including computed tomography, demonstrated a uterine mass that was identified as a choriocarcinoma following ovariohysterectomy. Additionally, numerous exfoliated quills were discovered throughout the abdomen, most of which were removed during the surgical procedure. Ultimately, development of peritonitis despite medical care led to the porcupine's death. Necropsy confirmed a wide migration of the quills with extensive serosal adhesions and granulomas affecting liver, lungs, urinary bladder, kidneys, and gastrointestinal tract.

Luteal maintenance of pregnancy in the African elephant (Loxodonta africana).

The ovaries of eight African elephant foetuses and their mothers between 2 and 22 months of gestation, and those of two cycling and two lactating elephants, were examined grossly, histologically and immunocytochemically, with emphasis on the development and regression of accessory corpora lutea (CL) of pregnancy and the steroidogenic capacities of the accessory CL and the foetal ovaries. The results supported recent findings that the accessory CL form as a result of luteinisation, with and without ovulation, of medium-sized follicles during the 3-week inter-luteal period of the oestrous cycle. They enlarge significantly and become steroidogenically active around 5 weeks of gestation, probably in response to the placental lactogen which is secreted by the implanting trophoblast of the conceptus. The large luteal cells stained strongly for 3ß hydroxysteroid dehydrogenase (3ßHSD) activity throughout the 22-month gestation period although they showed vacuolation and other degenerative changes in the final months of gestation coincident with hypertrophy and hyperplasia of 3ßHSD-positive interstitial cells in the foetal gonads. It is proposed that the progestagens secreted by the enlarged gonads of the elephant foetus may function both to assist the maternal ovaries in supporting the pregnancy state and to induce torpor and intrauterine immobility of the rapidly growing foetus.

An overview of molecular and cellular mechanisms associated with porcine pregnancy success or failure.

Prenatal mortality remains one of the major constraints for the commercial pig industry in North America. Twenty to thirty per cent of the conceptuses are lost early in gestation and an additional 10-15% is lost by mid-to-late gestation. Research over the last two decades has provided critical insights into how uterine capacity, placental efficiency, genetics, environment, nutrition and immune mechanisms impact successful conceptus growth; however, the exact cause and effect relationship in the context of foetal loss has yet to be determined. Similar to other mammalian species such as the human, mouse, rat, and primates, immune cell enrichment occurs at the porcine maternal-foetal interface during the window of conceptus attachment. However, unlike other species, immune cells are solely recruited by conceptus-derived signals. As pigs have epitheliochorial placentae where maternal and foetal tissue layers are separate, it provides an ideal model to study immune cell interactions with foetal trophoblasts. Our research is focused on the immune-angiogenesis axis during porcine pregnancy. It is well established that immune cells are recruited to the maternal-foetal interface, but their pregnancy specific functions and how the local milieu affects angiogenesis and inflammation at the site of foetal arrest remain unknown. Through a better understanding of how immune cells modulate crosstalk between the conceptus and the mother, it might be possible to therapeutically target immune cells and/or their products to reduce foetal loss. In this review, we provide evidence from the literature and from our own work into the immunological factors associated with porcine foetal loss.

p53-dependent apoptosis suppresses radiation-induced teratogenesis.

About half of human conceptions are estimated not to be implanted in the uterus, resulting in unrecognizable spontaneous abortions, and about 5% of human births have a recognizable malformation. In order to find clues to the mechanisms of malformation and abortion, we compared the incidences of radiation-induced malformations and abortions in p53 null (p53-/-) and wild-type (p53+/+) mice. After X-irradiation with 2 Gy on day 9.5 of gestation, p53-/- mice showed a 70% incidence of anomalies and a 7% incidence of deaths, whereas p53+/+ mice had a 20% incidence of anomalies and a 60% incidence of deaths. Similar results were obtained after irradiation on day 3.5 of gestation. This reciprocal relationship of radiosensitivity to anomalies and to embryonic or fetal lethality supports the notion that embryonic or fetal tissues have a p53-dependent "guardian" of the tissue that aborts cells bearing radiation-induced teratogenic DNA damage. In fact, after X-irradiation, the number of cells with apoptotic DNA fragments was greatly increased in tissues of the p53+/+ fetuses but not in those of the p53-/- fetuses.

A case of schistosoma reflexum in a cat with chromosomal aberrations.

A 2-year-old, female Persian cat was presented with a history of distocia. In her first pregnancy, she had whelped four kittens and had eaten all of them right after parturition. She had mated again with the same tomcat. Well-developed foetuses with weak foetal heart beats were observed in the ultrasonographic examination. En block ovariohysterectomy was performed. Three live and mature foetuses were obtained from the uterus; two of them were female foetuses and had no anatomical problem but the third one exhibiting multiple malformations was a male and diagnosed as 'schistosoma reflexum' (SR). The vertebral column deviated markedly to the right (scoliosis) at thoracolumbar region, and the middle lumbar and the sacral vertebrae were directed dorsocranially (lordosis). The entire small intestine, a part of large intestine, stomach, spleen and the right kidney were displayed out of the body, and it seemed that the listed internal organs were protruded from an abdominal cleft associated with the allantoic membrane. Liver, lungs and heart were hypoplastic. The large intestine was seen to have blind end (atresia recti), but anus was normal. Cerebrum and cerebellum were noticed as normal in sizes. Chromosome preparations from lymphocyte cultures of the foetus showed chromosomal aberrations including chromatid and chromosome breaks, exchange figures, non-homologous pairing, whereas no abnormalities were detected in the chromosome preparations from mother's cultures. This is probably the first case of SR in a cat, which was examined in detail from clinical, pathological, radiological and chromosomal angles.

Premature lactation and retention of a mummified fetus with live birth of the co-twin in a primiparous Morgan mare.

This report describes a primiparous 8-year-old Morgan mare, which displayed premature lactation that began at approximately 240 d of gestation and lasted approximately 4 wk. The premature lactation resolved spontaneously, and the pregnancy was subsequently carried to full term with the delivery of a live foal and a mummified fetus.

Dystocia in a rabbit (Oryctolagus cuniculus).

A 4-year-old female dwarf lop rabbit was presented with dystocia after mis-mating. Abdominal palpation, vaginal examination, and radiography confirmed that the doe was carrying 3 kits. Treatment for the dystocia consisted of gentle manual extraction of the fetuses and fetal membranes, and administration of oxytocin and calcium borogluconate.

Assessment of fetal well-being in cattle by ultrasonography in normal, high-risk, and cloned pregnancies.

This study determined ultrasonographic parameters of fetuses and uterine adnexa in late pregnancy in normal, cloned, and high-risk pregnancies in relation to perinatal and neonatal outcome. Ten cows with normal pregnancies (CONTROL, mean pregnancy length 273 d), 10 sick cows with potentially compromised pregnancies (HIGH-RISK, mean pregnancy length 267 d), and 10 heifers with cloned pregnancies (CLONED, mean pregnancy length 274 d) were examined at more than 260 d of gestation. There was no difference in mean fetal heart rates among the groups. The cloned calves were heavier (57 ± 8 kg) than calves from CONTROL group (36 ± 7 kg), and calves from HIGH-RISK group (37 ± 13 kg) (P = 0.003). The diameter of the thoracic aorta was positively correlated (R = 0.62) with fetal birth weight in the CONTROL group (P = 0.01). Fetal activity was not associated with survival. The results suggest that transabdominal ultrasonographic assessment of the fetal well-being may serve as a potential tool for evaluation of the fetoplacental unit.

Prevalence and economic implications of calf foetal wastage in an abattoir in Northcentral Nigeria.

The study was conducted to evaluate the volume of pregnant cows slaughtered at Minna abattoir, Niger State, Nigeria between 2001 and 2009 based on abattoir meat inspection records. Of the 98,407 cows slaughtered, 4,368 were pregnant, translating to a ratio of one calf foetal wastage in every 23 cows slaughtered. The wastage was significantly (P<0.05) high during the early rainy season (April to June). There was no significant difference observed across the years. The economic impact of the wastage is estimated at N8, 353,800.00 ($56,828.57) which is a great loss to the livestock industry. With these findings, there is the need to advocate for adequate enforcement of legislations on routine veterinary examinations at the slaughter houses in Nigeria. Also, livestock owners should be educated on the seasonal breeding patterns of cattle in order to avoid selling cows during the calving season to salvage high level of calf foetal wastage.

Aberrant growth and pattern formation in Peromyscus hybrid placental development.

Crosses between the North American deer mouse species Peromyscus maniculatus (BW) and P. polionotus (PO) produce dramatic asymmetric developmental effects. BW females mated to PO males (female bw × male po) produce viable growth-retarded offspring. In contrast, PO females mated to BW males (female PO × male BW) produce overgrown but dysmorphic conceptuses. Most female PO × male BW offspring are dead by midgestation; those surviving to later time points display numerous defects reminiscent of several diseases. The hybrid effects are particularly pronounced in the placenta. Here we examine placental morphological defects via histology and in situ hybridization as well as the relationship between growth and mortality in the female PO × male BW cross. These assays indicate altered hybrid fetal:placental ratios by the equivalent of mouse (Mus) Embryonic Day (E) 13 and disorganization and labyrinth defects in female PO × male BW placentas and confirm earlier suggestions of a severely reduced junctional zone in the female bw × male po hybrids. Further, we show that both cellular proliferation and death are abnormal in the hybrids through BrdU incorporation and TUNEL assays, respectively. Together the data indicate that the origin of the effects is prior to the equivalent of Mus E10. Finally, as the majority of these assays had not previously been performed on Peromyscus, these studies provide comparative data on wild-type placentation.

Ultrasonographically documented early pregnancy loss in an Asian elephant (Elephas maximus).

Early embryonic resorption or fetal loss is known to occur occasionally in captive elephants; however, this has mostly been reported anecdotally. The present study documents the case of a 24-year-old, multiparous Asian elephant cow that suffered embryonic death and resorption at around 18 weeks of gestation. From ovulation onwards, this female was sonographically examined 58 times. Blood was collected twice weekly for progestagen determination via enzyme immunoassay. On Day 42 after ovulation, a small quantity of fluid was detected in the uterine horn, which typically indicates the presence of a developing conceptus. Repeated inspections followed what appeared to be a normal pregnancy until Day 116. However, on Day 124, signs of embryonic life were absent. Progestagen concentrations started declining two weeks later, reaching baseline levels one month after embryonic death. Retrospectively, ultrasound examination revealed several abnormalities in the uterine horn. Besides an existing leiomyoma, multiple small cystic structures had formed in the endometrium at the implantation site and later in the placenta. These pathological findings were considered as possible contributors to the early pregnancy failure. PCR for endotheliotropic elephant herpes virus (EEHV) (which had occurred previously in the herd) as well as serology for other infectious organisms known to cause abortion in domestic animals did not yield any positive results. Although no definitive reason was found for this pregnancy to abort, this ultrasonographically and endocrinologically documented study of an early pregnancy loss provides important insights into the resorption process in Asian elephants.

Effects of cumulative stressful and acute variation episodes of farm climate conditions on late embryo/early fetal loss in high producing dairy cows.

The aim of this study was to determine possible relationships between farm climate conditions, recorded from day 0 to day 40 post-artificial insemination (AI), and late embryo/early fetal loss in high producing dairy cows. Pregnancy was diagnosed by rectal ultrasonography between 28 and 34 days post-AI. Fetal loss was registered when a further 80- to 86-day diagnosis proved negative. Climate variables such as air temperature and relative humidity (RH) were monitored in the cubicles area for each 30-min period. Temperature-humidity indices (THI); cumulative stressful values and episodes of acute change (defined as the mean daily value 1.2 times higher or lower than the mean daily values of the 10 previous days) of the climate variables were calculated. The data were derived from 759 cows in one herd. A total of 692 pregnancies (91.2%) carried singletons and 67 (8.8%) carried twins. No triplets were recorded. Pregnancy loss was recorded in 6.7% (51/759) of pregnancies: 5.6% (39/692) in single and 17.9% (12/67) in twin pregnancies. Using logistic regression procedures, a one-unit increase in the daily cumulative number of hours for the THI values higher than 85 during days 11-20 of gestation caused a 1.57-fold increase in the pregnancy loss, whereas the likelihood of fetal loss increased by a factor of 1.16 for each additional episode of acute variation for the maximum THI values during gestation days 0-40. THI values higher than 85 and episodes of acute variation for the maximum THI values were only recorded during the warm and cool periods, respectively. The presence of twins led to a 3.98-fold increase in pregnancy loss. In conclusion, our findings show that cumulative stressful and episodes of acute variation of climatic conditions can compromise the success of gestation during both the cool and warm periods of the year. Twin pregnancy was confirmed as a main factor associated with pregnancy loss.

Ultrasound and endocrine findings that help to assess the risk of late embryo/early foetal loss by non-infectious cause in dairy cattle.

This report reviews the clinical applications of routine ultrasound in gestation control programmes for dairy herds. Emphasis is placed on identifying risks of late embryo/early foetal loss of non-infectious cause by monitoring ovarian structures (as opposed to uterine contents), indicators of pregnancy loss and twin pregnancies. Suggestions are provided to appropriately manage a cow at risk of pregnancy loss during the late embryonic/early foetal period. This review identifies gaps in our current knowledge of the aetiology of pregnancy loss and spontaneous embryo/corpus luteum reduction. Two areas of the implantation-placentation window of gestation in particular need urgent attention: the roles in pregnancy loss of immune-endocrine interactions and the physiological status of the embryo/corpus luteum. The latter issue and consecutively endocrine interactions could be successfully addressed by incorporating Doppler ultrasonography into routine ultrasound procedures.

Effect of the reproductive state of female alpacas on embryonic mortality rate.

OBJECTIVE: To study the effect of the reproductive state of female alpacas (ie, maiden [never bred before], barren [bred but failed to conceive or maintain pregnancy in previous breeding season], or gave birth and currently lactating) on embryonic mortality rate. ANIMALS: 167 female alpacas (54 lactating, 44 barren, and 69 maiden) that ovulated following a single breeding. PROCEDURES: During the first 45 days following breeding, female alpacas underwent periodic transrectal ultrasonography to determine the presence or absence of an embryonic vesicle. Serum progesterone concentrations were determined during the same period. Embryonic survival rate was analyzed for each group of females (lactating, barren, and maiden). RESULTS: The presence of an embryonic vesicle or embryo was positively associated with high serum progesterone concentrations (>2 ng/mL). The embryonic mortality rate in barren females (21/44 [47.7%]) was significantly higher than in maiden (20/69 [29.0%]) and lactating (16/54 [29.6%]) females. In females that underwent embryonic loss (n=57), 3 patterns of events in terms of serum progesterone concentrations were identified: concomitant decrease of serum progesterone concentration and embryonic loss (24/57 [42.1%]), decrease in serum progesterone concentration before embryonic loss (12/57 [21.1%]), and persistent serum progesterone concentrations beyond embryonic loss (21/57 [36.8%]). Patterns of serum progesterone concentration and embryonic loss did not differ significantly among lactating, barren, and maiden female alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Embryonic loss in alpacas occurred without any discernible pattern in serum progesterone concentrations. Barren female alpacas had the highest embryonic mortality rate.

Influence of egg warming during storage and hypercapnic incubation on egg characteristics, embryonic development, hatchability, and chick quality.

Negative effects of prolonged egg storage on hatchability and chick quality may be caused by changes in the embryo or in the egg characteristics, or by both. The aim of this experiment was to investigate whether prestorage incubation (PSI), frequent warming during storage (FW), or hypercapnic incubation (HI) during the first 5 d of incubation affect egg characteristics, embryonic development, hatchability, and chick quality. The experiment had a 2 × 2 × 2 randomized design: PSI (yes-no), FW (yes-no), and HI (yes-no). All eggs were stored for 15 d at 16°C and 75% RH. On the second day after oviposition, half of the eggs were incubated for 7 h (PSI). During storage, half of the eggs were warmed 6 times for 30 min in water at 37.8°C (FW). During the first 5 d of incubation, the CO(2) concentration in the incubator was maintained between 0.70 and 0.80% (HI) or increased from 0.05 to 0.20% (control). Prestorage incubation and FW increased the stage of embryonic development and the number of viable embryonic cells, but these treatments did not have a pronounced effect on egg characteristics, hatchability, or chick quality. Hypercapnic incubation decreased total albumen pH, which was measured at 18, 42, 66, and 90 h of incubation, and the percentage of eggs classified as infertile (Δ = 1.2%). In contrast, HI retarded embryonic development, decreased hatchability of fertile eggs by 1.3%, but did not affect chick quality. We conclude that both PSI and FW did not improve hatchability and chick quality, although the stage of embryonic development and the number of viable embryonic cells increased due to the treatments. Hypercapnic incubation decreased total albumen pH, which may be related to the increased number of embryos that continued their development at the onset of incubation. Because HI retarded further embryonic development and decreased hatchability, long-term stored embryos were probably sensitive to the CO(2) concentration of 0.70 to 0.80% between 48 and 72 h of incubation.

High- and low-temperature manipulation during late incubation: effects on embryonic development, the hatching process, and metabolism in broilers.

Temperatures continuously higher and lower than the standard incubation temperature by 3°C from embryonic d 16 until embryonic d 18.5 result in differential effects on embryonic development, the hatching process, and embryonic metabolism. Embryos in the high-temperature group were forced into a state of malnutrition by the temperature treatment, as reflected by reduced embryo growth and yolk consumption, resulting in a significantly lower chick weight at hatch. In addition, altered air cell and blood gases as well as a retarded hatching process further indicated reduced growth of embryos exposed to higher incubation temperatures during the latter part of incubation. In addition, hatchability was significantly reduced by the high-temperature treatment due to higher embryonic mortality during the treatment period and the hatching process. Levels of blood glucose, lactate, liver glycogen, plasma triglycerides, and nonesterified fatty acids indicated an altered carbohydrate and lipid metabolism for the high-temperature group. Although the hatching process of embryos exposed to lower incubation temperatures was also significantly retarded, their embryonic development and growth were strikingly similar to those of the control group.

Urogenital leiomyosarcoma in an alpaca.

A mass in the pelvic canal of a 4-year-old pregnant alpaca hembra diagnosed as leiomyosarcoma of the urogenital tract was confirmed by biopsy. Following a tube cystotomy, the alpaca was presented 33 d later, 2 d after the tube cystotomy had been dislodged. A dead cria was delivered by caesarean section.