Hernia

From Cow
Umbilical hernia in a calf[1]
Intraoperative view of the calf in dorsal recumbency. The exteriorized GI tract, abomassum and small intestines had herniated through the diaphragmatic tear[2]

Hernias are a relatively common congenital disorder of cattle.

Various types of hernias are recognized in cattle including:

  • Umbilical hernia
  • Diaphragmatic hernia
  • Omental herniation
  • Hiatal hernia

Umbilical hernia

Umbilical hernia are a congenital defect resulting from failure of the normal closure of the umbilical ring, resulting in the protrusion of abdominal contents into the overlying subcutis.

The umbilicus in newborn calves consists of the urachus (a tube that attaches the fetal bladder to the placental sac) and the remnants of the umbilical vessels that transport blood between the fetus and its mother. Normally, just after birth these structures shrink until only tiny remnants remain within the abdomen. If the area in the body wall through which these structures passed remains open, abdominal contents can protrude through the defect resulting in an umbilical hernia[3]. Hernia size varies depending on the extent of the umbilical defect and the amount of abdominal contents contained within it. Umbilical hernias are the most common birth defects in calves, especially in Holstein-Friesians.

Multiple births and shortened gestation lengths are two important risk factors for congenital umbilical hernias in calves[4].

Most umbilical hernias are repaired with minimal surgical intervention.

Diaphragmatic hernia

Neonatal diaphragmatic hernia may be congenital or acquired. Traumatic hernias are caused by mechanical factors such as pregnancy, falls, or dystocia. The increased abdominal pressure during parturition may induce a rupture in the diaphragm of the calf and the development of a hernia[5].

Rapid diagnosis is essential if surgical treatment is to be attempted. Diaphragmatic hernia should be suspected in a newborn calf with dyspnea, absence or asymmetry of lung sounds, borborygma upon thoracic auscultation, tympanism, and colic. A wide range of signs are possible depending on the size and the location of the hernia and the amount and type of viscera displaced[6].

Unfortunately, most diaphragmatic hernia are diagnosed postmortem[7].

Omental herniation

Omental herniation in cattle is usually an acquired condition due to an omental rent or tear.

Clinical signs were indistinguishable from other causes of mechanical ileus. In most cases, an exploratory laparotomy is necessary to establish a diagnosis. In most cases a variably sized portion of jejunal loops becomes obstructed in the rent in the deep layer of the greater omentum[8].

Treatment involves simple reduction of the tear. In severe cases, resection of gangrenous loops may be necessary.

References

  1. Sutradhar BC et al (2009) Comparison between open and closed methods of herniorrhaphy in calves affected with umbilical hernia. J Vet Sci 10(4):343-347
  2. Bellavance A et al (2010) Surgical correction of a diaphragmatic hernia in a newborn calf. Can Vet J 51(7):767-769
  3. Hayes HM (1974) Congenital umbilical and inguinal hernias in cattle, horses, swine, dogs and cats: Risk by breed and sex among hospital patients. Am J Vet Res 35:839–842
  4. Herrmann R et al (2001) Risk factors for congenital umbilical hernia in German Fleckvieh. Vet J 162:233–240
  5. Kelmer G et al (2008) Diaphragmatic hernia: Etiology, clinical presentation, and diagnosis. Comp Cont Ed Equine Edition 3:28–35
  6. Kelmer G et al (2008) Diaphragmatic hernia: Treatment, complications, and prognosis. Comp Cont Ed Equine Edition 3:37–45
  7. Hunter R (1980) Diaphragmatic hernia in a newborn calf. Vet Med Small Anim Clin 75:315
  8. Pardon B et al (2009) Four cases of omental herniation in cattle. Vet Rec 165(24):718-721