Fog Fever Archives | Octavoscene (Pty) Ltd

Fog Fever

December 10, 2021

Atypical interstitial pneumonia (Fog Fever)

Octavoscene Livestock, Livestock Diseases, Newsletter Atypical interstitial pneumonia, chlortetracycline, Fog Fever

Introduction:Atypical interstitial pneumonia, also commonly known as fog fever, is a syndrome farmers see in their cattle after placing the animals on lush green grazing. Animals that are fed a dry ration prior to grazing lush pastures are more likely to be affected by this syndrome. Fog fever is also known as acute bovine pulmonary oedema and emphysema (ABPEE). Disease progression:Cattle affected by this syndrome have been on dry feed for extended periods of time and the rumen fermentation pattern has adapted to this situation. With the change to lush green pasture the dietary protein concentration increases dramatically. One of the amino acids in this plant protein, tryptophan, is the culprit. The tryptophan in the feed is converted by rumen bacteria to a substance called 3-methylindole (3-MI) at a very high rate.This 3-MI is absorbed through the rumen wall and circulated around the body. The 3-MI is toxic to the primary cells (Type 2 pneumocytes) that line the interior surface of the lungs at the alveolar-blood barrier. Thus, as the high levels of 3-MI move from the rumen to the lungs, more and more lung tissue is destroyed. Clinical Signs:Difficulty breathingCoughingFrothing at mouthCattle do not normally run a fever- This is an extremely important point as the clinical signs seen with fog fever are very similar to those seen with Bovine respiratory disease.Anxiety (separation from group)CollapseDeath Treatment:Unfortunately, there is no specific treatment for fog fever. Mild cases may recover without treatment, should they be caught early enough. Most severely affected cattle will not […]

April 25, 2019

AIP in the Feedlot

Octavoscene Livestock Diseases Acute Bovine Pulmonary Emphysema, AIP, Bovine Asthma, Edema, Feedlot, Feedlot Dust Pneumonia, Fog Fever

AIP in the Feedlot AIP is the acronym for Acute (or Atypical) Interstitial Pneumonia. This disease is known by various different names over the years, such as Acute Bovine Pulmonary Emphysema and Edema, Bovine Asthma, Feedlot Dust Pneumonia, Fog Fever and the list goes on. It is a primary respiratory disease that leads to severe edema and emphysema of the lung tissue that leads to death in the majority of cases. This is documented to be the second most important respiratory disease affecting feedlot cattle. The financial impact of AIP can be significant, since it normally affects cattle in the finishing stage of their feeding period, animals which by that time increased in value to the producer due to increased weight – the result of various costly inputs. Outside the feedlot setting, AIP is reported (often as outbreaks) on lush green pastures and fermented crops. Especially when moving animals from low quality roughage, to high quality pasture that have high protein levels. With a sudden increase in protein levels, L-Tryptophan (a common amino acid/or protein building block) is converted to 3-Methylindole (3-MI) in the rumen by bacterial species such Lactobacillus. 3-MI is then readily absorbed through the rumen into the bloodstream, and when it reaches the lungs it gets converted to 3-Methyleneindolenine (3-ME) and this molecule is then responsible for causing the damage to the lungs seen in AIP. The above description is accepted as the etiology for Fog Fever. In the feedlot setting however, there are no […]