Review/Oorsig Volume 22, Issue 03 - Page 5

Volume 22 • Issue 03 • 2018 you make your first incision. There are important occupational zoonotic hazards for veterinarians investigating abortions and stillbirths (Brucella, Q-Fever, Listeria, Rift Valley fever), so ensure that you wear protective clothing including overalls, gloves, goggles and masks. Handling aborted fetuses is the one scenario where Listeria does act as a zoonosis. Scan to view video allows aspiration of meconium contaminated amniotic fluid before delivery. Immediately after delivery meconium lodged in the nasopharynx can pass into the lung with the first breath of air. This aspirated meconial material can cause chemical (sterile) pneumonia in newborns but is also an ideal growth medium for secondary bacteria resulting in infectious pneumonia. Obvious congenital abnormalities are easily visible at gross examination Figure 3: Anemia Figure 1: Bovine meconial staining Figure 4: Icterus Figure 2: Ovine meconial staining Meconium staining and / or aspiration is the sign of a distressed fetus and usually occurs as a consequence of fetal hypoxia during dystochia or prolonged parturition. Meconium staining is characterized by yellow discoloration of the external surface of the fetus (figure 1 and figure 2) Hypoxia results in increased intestinal peristalsis and relaxation of the anal sphincter in the fetus resulting in release of meconium into the amniotic fluid. Meconium in the amniotic fluid can then gain access to the oropharynx of the fetus. Intra-uterine gasping with an open glottis Evaluate mucous membranes for evidence of anemia (figure 3 – pale mucous membranes) or icterus (figure 4 – yellow discoloration of mucous membranes). On the African Continent haemoparasites (Babesia, Anaplasma, Borellia) can be significant causes of abortion. Abortion is either due to invasion of the fetus and placenta by parasites or because of maternal pyrexia. Invasion of the fetus by parasites is usually accompanied by fetal pathology including anemia and/or icterus, while in cases of maternal pyrexia no fetal pathology is evident. Angulated limb abnormalities may be associated with in-utero viral infection, prussic acid poisoning or micronutrient imbalances. In cases of in-utero viral infection and prussic acid poisoning, these limb abnormalities are those of contracted tendons with arthrogryposis and are frequently accompanied by other skeletal abnormalities, hydranencephaly/hydrocephalus and/or ocular abnormalities (figure 5 and figure 6). 5