Fetal ascites & anasarca (hydrops fetalis)

Keywords: bovine, anasarca, ascites, dystocia, heritable, neoplasia, hypoplasia, IVF, clone, cloning

Ascites: < Greek askos; "a bag of wine"
Anasarca: < ana : "throughout" & sarca: "new flesh"
Hydrops fetalis: Abnormal accumulation of fluid in two or more fetal compartments, including ascites, pleural effusion, pericardial effusion, and skin edema.

A complex subject with varying appearances and many different etiologies. Hydrops fetalis (HF) may be due to any factor/s that cause passive venous congestion i.e. intra-peritoneal or intra-thoracic neoplasia (leiomyomas, teratomas hepatoblastomas), liver cirrhosis or other liver anomalies, cardiac anomalies, pulmonic valve stenosis or dysplasia of the lungs themselves. Some of these anomalies are heritable in several breeds of cattle. As is so often the situation with abnormal calves, the calf shown below (photographed 41 years ago!) was discarded without a thorough post mortem examination. Therefore the cause of ascites in this case was unknown.

Because of its enlarged abdomen and resulting dystocia, the calf (weighing 71 kg) was delivered by cesarean. A calf with ascites can often be delivered per vagina after incising its abdomen using a finger knife and allowing the fluid to drain into the cow's uterus. The yellow staining  of the hair coat here was due to meconium discharge from the anus; a common situation during fetal distress precipitated by hypoxia.

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In the fetus below (delivered by cesarean and also discarded without a thorough postmortem examination) there was ascites as well as marked anasarca. The calf showed a multitude of musculo-skeletal deformities too.

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In fetuses produced by assisted reproductive technology (ART) i.e. cloning through nuclear transfer (NT) and in vitro fertilization (IVF), pregnancy failure is common and many abnormalities have been described in calves, lambs and human babies produced through ART. The most striking of these is the so called "Large offspring syndrome" where newborn babies, calves and lambs can be several times their normal weight at birth. Cardiac, kidney, hepatic and pulmonary abnormalities have been described in these cases. In addition, angiogenesis itself can be abnormal, leading to increased permeability of blood vessels in the fetus and fetal membranes.

In the case shown below, the calf was a product of IVF and abortion occurred at 7 months of gestation. There was severe ascites and anasarca (HF) as well as hydrops amnion and allantois. The case is discussed in more detail in another LORI entry, featuring a video. In that video, the author suggests that genetic alterations may occur in these cases as a result of culture conditions. However, current information shows that the abnormalities manifested in cases of IVF and NT are largely epigenetic in nature.

The calf weight 56Kg; well in excess of the 8 to 18Kg range for a fetus of this gestational age. Meconium staining of the hair coat is obvious in this case as well.

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Pitting edema (below) was present over the entire surface of the calf and its fetal membranes.

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Subcutaneous edema is visible here, in the upper left inset. At lower right, a stream of ascitic fluid  is being released from the abdomen. Readers are encouraged to view the teaching video mentioned above to appreciate the nuances of this case.

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In conclusion, ascites, anasarca, placental edema, hydrops allantois and hydrops amnion are common manifestations of  various conditions that may or may nor be related to one another.

Selected references:

Alberto, M.L.V. et al. 2012. Development of bovine embryos derived from reproductive techniques, Reproduction, Fertility and Development. 25: 907-917

Baraya, Y.S. et al. 2015. Dystocia associated with foetal anasarca (hydrops fetalis) in a Nigerian breed of sheep; Case report. Proceedings: Sixth Pan Commonwealth Vet.Conf.of the CVA and 27th Vet. Assn. Malasia Conf. 519-522

Buchanan, J.W. 2001. Pathogenesis of single right coronary artery and pulmonic stenosis in English Bulldogs. J. Vet. Intern. Med. 15: 101-104

Chen, Z et al. 2013. Large offspring syndrome. A bovine model for the human loss-of-imprinting overgrowth syndrome Beckwith-Wiedemann. Epigenetics 8:591–601

De Vries, C. et al 2012. Congenital ascites due to hepatoblastoma with extensive peritoneal implantation metastases in a premature equine fetus. J. Comp. Path. 2012, 148: 69-69

Drost, M. 2007. Complications during gestation in the cow. Theriogenology. 68: 487-491

Edwards, J.L. et al. 2003. Cloning adult farm animals: A review of the possibilities and problems associated with somatic cell nuclear transfer. A. J. Reprod. Immunology. 50: 113-123

Golladay, E.S. and Mollit, D.L. 1984. Surgically correctable fetal hydrops. J.Pediatric Surgery.19: 59-62

Pinborg, A. et al. 2014. Large baby syndrome in singletons born after frozen embryo transfer (FET): is it due to maternal factors or the cryotechnique? Hum. Reprod. 9: 618-27

Pushp, M.K. et al. 2016. Dystocia in a non-descript cow due to ascetic fetus- a case report. J. Livestock Sci 7: 62-64

Rheuban, K.S. et al. 1991. Intrapericardial teratoma causing nonimmune hydrops fetalis and pericardial tamponade: A case report. Pediatric Cardiology. 12: 54–56

Roberts, S.J. 1986. Veterinary obstetrics and genital diseases. Diagnosis and treatment of various types of dystocia. pp 333-335. Published by the author, S.J. Roberts.

Sasaki S. et al. 2016. A missense mutation in solute carrier family 12, member 1 (SLC12A1) causes hydrallantois in Japanese Black cattle BMC Genomics 17:724 739

Svara, T. et al. 2016. Pulmonary hypoplasia and anasarca syndrome in Cika cattle. Acta Vet. Scand. 58: 36-40

Testoni, S.et al. 2009. Congenital facial deformities, ascites and hepatic fibrosis in Romagnola calves. Vet.Rec. 164: 693-694

Walker, S.K. et al. 1996. The production of unusually large offspring following embryo manipulation; concepts and challenges. Theriogenology 45: 11l-120 

Whitlock, B.K. et al. 2008. Heritable bovine fetal abnormalities. Theriogenology. 70: 535-549

Windsor, P.A. et al. 2006. Hydrops fetalis associated with pulmonary hypoplasia in Dexter calves.

Australian Vet. J. 84: 278-281

Young, L.E. et al. 1998. Large offspring syndrome in cattle and sheep. Reviews of reproduction. 3: 155-163

A conjoined januceps (janiceps) fetus

Keywords: Mongolia, Richardson, bovine, conjoined, dystocia

A tongue in cheek commentary on an interesting series of images kindly lent to the author by Dr Heather Richardson (heathrichardson@hotmail.com). Dr Richardson spent time performing veterinary services and supporting veterinary education in rural Mongolia. This shows how she delivered a januceps fetus by cesearean section under rather unusual conditions.

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From top L to R and bottom L to R):  A rainstorm threatened to disrupt surgery. Therefore, despite the presence of family treasures and fine carpets, the cow with dystocia was brought into the ger (yurt) for the cesarean section. Dr Richardson commented that it was only the mother of the family who seemed concerned over the fate of their carpets (ringed). The animal was prepared for surgery with resignation on her part.

Fortunately the clouds parted and the cow was led from the ger to the spacious operating room just outside. The final image in the collage shows one of the calve's limbs being exteriorized prior to incising the uterus.

Examination of the calf showed the exact cause of dystocia; a januceps fetus with a single central ear.

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Because of the advanced age of the cow (18 years) and a prolonged struggle to deliver the calf by several people, a guarded prognosis was given for recovery.

In the formation of conjoined twins, division of the embryo into two individuals begins later than in other forms of identical twins and the process of division is never completed. The primitive streak may start to split caudally or cranially. Accordingly, twins may be conjoined either cranially or caudally. When division of the primitive streak begins cranially and does not progress beyond the occipital bones of the skull, the animal develops two incomplete heads. The condition is named for the Roman god Janus who looks both into the past and future. Therefore the name januceps is more appropriate than janiceps, the commonly accepted term.

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Schistosoma reflexus.

Keywords: dystocia, shistosoma, reflexus, bovine

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An image of female schistosoma reflexus beef (SR) calf. The hind legs are reflected over the head as shown and the viscera are totally exposed. Schistosoma (or closely related syndromes) occur in most mammals, including humans but it is only in ruminants that the total reflection of the limbs and body occur frequently. In other species, the body wall is often split (schistosoma) but the body is seldom reflected (reflexus).

SR is a defect resulting from incomplete folding of the embryo after embryonic folding. This excellent animation  shows the "folding" process in a human embryo. If you have a veterinary or animal science background, you will find it interesting to see the allantois vanish in that animation.

Fairly recent data (see references) suggest that SR is a heritable defect, caused by an abnormal autosomal recessive gene. In one study, SR occurred at a frequency of about 1% in approximately 7000 cases of dystocia. Interestingly 60% of those cases were resolved by fetotomy, 25% by cesarean section and 3% by mutation and traction. The remainder were euthanized.  Others have reported lower incidence of SR than 1%.

Selected references

Citek, J. 2012 Pedigree analysis of Czech Holstein calves with schistosoma reflexum. Acta Vet. Scand. 54:22

Knight, R.P. 1996. The occurrence of schistosomus reflexus in bovine dystocia. Australian Vet. J. 73: 105–107

Laughton K.W. et al 2005, Schistosomus Reflexus Syndrome: A Heritable Defect in Ruminants Anat. Histol. Embryol. 34: 312–318