Other supplement targets
Colostrum and milk
Milk is considered the ideal nutritional source for the immature digestive system to meet a calf’s needs. Quite separate from its nutritional benefits, milk contains features which may aid the recovery of the damage of the intestine and the recovery of normal function. This includes some components which stimulates the mucus activity from goblet cells (metabolism and secretion) with mucus acting as a local barrier to pathogenic invasion. It may reduce the attachment of various pathogens E coli to the enterocytes. Or it may reduce rotavirus replication (Juntenen at al 2001).
The components in milk affecting goblet cells include growth factors (EGF, TGF-β, and KGF) found in milk (and colostrum), and parts of the casein fraction specifically β-casomorphin. (Plaisancie 2006). Milk may also act through its effect on bacterial populations and their effect on the innate and acquired immune system. EGF and its analogs are targeted for development as they have been shown to improve recovery by reducing inflammatory processes.
There is a correlation between each of the following factors: (in animal models) (refer Doig et al, 1998)
Mucosal ischaemia (loss of blood flow)
Extent of the pathological injury to the mucosa
Severity of intestinal permeability
Severity of bacterial translocation
In order to advance treatment of the recovery of calves from intestinal infections including re-hydration with electrolytes, nutritional support including the use of targeted energy sources may improve treatment outcomes. These targeted sources may include supplements of anti-oxidants to reduce the increase in intestinal permeability (De Souza & Greene 2005). These anti-oxidants may act to limit cytokine activation, and reduce the central behavioural response to abdominal discomfort (see below) – leading to loss of appetite.
These may be further aided by
- Limiting further mucosal injury (by avoiding hypertonic fluids),
- Improving the rate of fluid re-hydration by minimizing fluid losses at the membrane (alanyl-glutamine).
Alanyl-glutamine is a precursor of glutathione an important anti-oxidant for the intestinal and hepatic
- Recognizing that the early severe insult from infections in spite of the above will in some calves lead
to intestinal permeability changes, and
- Bacterial translocation will then become important. Recognizing the clinical signs of septicaemia
becomes an important challenge separate from recognition of signs of de-hydration, hypothermia, and
- Early re-hydration may be one of the most important ways to limit severe outcomes. (Early rehydration should be the fastest possible rehydration).