Advanced pregnancy Oesophageal obstruction Gastrointestinal obstruction

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2.8.2 Free gas bloat

Inflammation such as from warts or penetrating wire or a foreign body such as plastic or string in the area around the oesophageal groove can interfere with eructation and cause free gas bloat. Usually only individuals are affected. Resolution may require antibiotics, or surgery to create a rumen fistula, or the passage of time, or all three. Consider inserting a commercially available plastic, self-retaining cannula. The accompanying trochar is not usually robust enough to penetrate the skin so it is best to make an incision with a scalpel at the intended place of cannula insertion. Make a vertical incision through skin and underlying fascia of a length equal to twice the diameter of the cannula body. With the trochar in place in the lumen of the cannula, sharply thrust through the abdominal and rumen walls. With the trochar still firmly in place, screw the cannula in so that the spiral flange holds the rumen firmly against the abdominal wall. The trochar is then removed and the gas allowed to escape. Gas escape is best controlled in order to avoid a sudden fall in blood pressure that accompanies the sudden fall in intra- abdominal pressure. The cannula can remain in place for as long as necessary, which may be as long as two weeks. A stomach tube passed down the oesophagus into the rumen can be used to relieve free gas bloat. However, severely distended cattle have been known to drop dead when this has been done.

2.8.3 Advanced pregnancy

Pregnancy of six months or more may be detected by ballottement through the right abdominal wall.

2.8.4 Oesophageal obstruction

Oesophageal obstruction may occur from feed impaction but also if a fruit or vegetable of critical size has found its way into a feed trough. Dehydration, poor feed quality and problems with chewing teeth or tongue injury may predispose. Bloat and profuse salivation will usually be observed. Treatment options include sedation with xylazine to relax the oesophagus that might be in spasm and gentle passage of a stomach tube to try to force the obstructing mass into the rumen. An obstructing mass can sometimes be quickly and easily removed from the proximal oesophagus by an experienced operator reaching down the throat. Alternatively, an obstruction in the cervical oesophagus may be able to be massaged up to and into the pharynx by pressing the fingers into each side of the ventral neck behind the mass. When at the level of the pharynx, keep the fingers pressed into the oesophagus until the animal ejects the mass. If the mass is in the lower cervical or thoracic oesophagus, a carefully manipulated loop of wire passed down the oesophagus by an experienced operator may be worth a try.

2.8.5 Gastrointestinal obstruction

Gastrointestinal obstruction can have many causes including foreign bodies, intussusceptions, volvuli and displacements affecting the abomasum and small and large intestines. Dislodgement of benign abomasal bezoars into the intestine associated with 18 dietary change is usually lethal. Both phytobezoars and trichobezoars may occlude the pylorus or intestine with like result. Affected cattle may show signs of abdominal pain, be inappetent and pass no faeces, or scant faeces covered in mucus or blood. Rectal examination can be expected to reveal a completely empty rectum with a dry but sticky feel. A ping and sloshing fluid may be detected upon auscultation and ballottement of a distended abdomen. With the exception of left displacement of the abomasum, bold and early surgical intervention and often fluid therapy are required to save the animal. Successful surgery is often performed for LDA, but the need is not so urgent. If suitable facilities and equipment are not available, and with the possible exception of LDA, prompt euthanasia of the animal should be performed.

2.8.6 Vagal indigestion