The fetal fluids were amber in color (Fig 2); on careful examination, the calf was found to be defective (Fig 3) with external hydrocephalus and cleft palate (Fig 7). Wrinkled skin with mild degree of arthrogryposis were also observed. The fetal membrane weighed 8.5 Kg and it had only 28 numbers of cotyledons which could be noticed only in the gravid uterine horn and were larger (19 x 12 cm) than usual (Fig 4). The rest of the fetal membranes were adventitious in nature. Thinning of cranium with dome shape was observed upon radiographic examination the fetal head. On dissection of skin, failure in fusion of cranial bones were noticed (Fig 5, 6) with absence of cerebral atrophy.
Leipold and Dennis (1980) reported recessive gene expression could be the factor of hydramnios and it’s congenital in nature gene.
Jackson (1995) stated that hydramnios was often associated with cranial malformation such as cleft palate which might result in improper swallowing, which led to accumulation of amniotic fluid.
Shupe et al., (1968) reported that Lupine (Indian beet) and hereditary as the factors responsible for cleft palate leading to hydramnios. Congenital hydrocephalus caused by a lethal autosomal recessive gene with incomplete penetration had been reported in cattle which are termed as neuropathic
(Jubb and Kennedy, 1970).
Katiyar et al., (2020) reported that hydramnion coupled with fetal anasarca in a doe due to placental origin.
Microscopically the placental tissue showed more of connective tissue covered with trophoblast. The connective tissue contained numerous blood vessels. The tunica media of blood vessels were thickened (medial hypertrophy) (Fig 8 and 9). Cotyledonary area was made up of mesenchymal tissue covered with a single layer of trophoblast. Average thickness of artery in adventitious portion was 10.37 µ and in normal it was 1.87 µ.
Etiology of hydrallantois was frequently associated with diseased uterus and in which major portion of caruncles were atrophied. In such circumstances the presence of few caruncles may become enlarged as a compensatory mechanism and rest of the portion become adventitious. Similar results were reported by
Drost (2007).
Cooke et al., (2013) reported that development of uterine glands (adenogenesis) started immediately after birth and lasted for few weeks; prenatal progestins inhibited the uterine epithelial proliferation by influencing the gene expression (Hox, Wnt
etc and resulted in congenital disorders of the endometrial organization which could lead to hydrallantois.
Fride (1975) stated that disturbances in normal circulation of cerebrospinal fluid due to distorted production might lead to hydrocephalus. In internal hydrocephalus the fluid was in the ventricular system; while in external hydrocephalus the fluid was in the arachnoid space and in communicating hydrocephalus the fluid was in boththe locations.
Jubb and Kennedy (1970) reported that external hydrocephalus was often congenital and could also occur due to hypovitaminosis A.
Leipold and Dennis (1980) reported that in cattle, expression pattern of simple autosomal recessive gene and autosomal gene with incomplete penetrance had been associated with hydrocephalus. Possibility of external hydrocephalus was either due to excess production of fluid nor obstruction in drainage of fluid
(Shastry, 1971). Leptin receptors in placenta could regulate metabolism and sustain the fetal nutritive demand by influencing the hematopoiesis angiogenesis mechanism
Priyadarshini et al., (2015).
Undeviating alteration of caruncular structures of the endometrium lead to adventitious placenta and prognosis was guarded
(Drost, 2007). Role of heparin binding angiogenic factors in differentiation of placental endothelium resulted in establishment of circulatory network between dam and fetus
(Reynolds and Redmer, 1995).
Raja et al., (2017) stated that the stimulating factor for activation of adventitious placental circulation is yet to be explored. Inspite of increased mesenchymal connective tissue, there were more number of blood vessels present in the connective tissue, which might be helped in the diffusion of nutrients to fetus from the endometrium.